School Science Lessons
Banana Project
2014-03-22
Please send comments to: J.Elfick@uq.edu.au

Preface

Table of contents
See websites: Bananas
1.0 Banana Project
1.1 Village bananas and cultivated bananas
1.2 Varieties of bananas
1.3 Banana language

2. Leaf
3. Leaf growth
4. False stem
5. Corm
6. Roots
7. Inflorescence, (Flowers)

8. Choosing a site
9. Preparing ground
10. Planting material
11. Planting

12.0 Plant care
12.1 Bunch covering
12.2 Desuckering and debelling
12.3 Fertilizing
12.4 Mulching and watering
12.5 Propping
9.159 Rotting bananas
12.6 Trashing, deleafing
12.7 Weeding

13.0 Insect pests
13.1 Banana root nematode
13.2 Banana weevil borer, banana root borer, "banana beetle", Cosmopolites sordidus
13.3 Banana scab moth, Nacoleia octasema
14.0 Diseases
14.1 Bunchy top
14.2 Panama disease, (Fusarium wilt)
14.3 Black sigatoka disease
14.4 Comparing bacterial wilt and fusarium wilt

15. Fruit bunch
16. Harvesting
17. Ripening and handling
18. Uses of bananas
20. Grow bananas at home
6.9.20.0 Calculate the profit for the Banana Project after one year
History

1.1 Village bananas and cultivated bananas
See Diagram 51.1: Village banana plant and cultivated banana | See diagram 51.1.1: Banana plants
Bananas can be grown on atolls but it needs special care to make them grow well. The aim of this project is to show how to increase the yield of bananas and grow bananas for profit. You will need examples of village and cultivated bananas or use the diagrams. There are hundreds of different kinds of bananas but in this it is important that you teach the difference between traditional, (wild), bananas and cultivated bananas, Musa acuminata.
What are the different kinds of bananas used at home? Are all bananas the same? What are the different types of village bananas? What are the different uses of village bananas? There are two main kinds of bananas, traditional bananas and cultivated bananas. Traditional bananas grow wild and are easy to grow. Cultivated bananas were introduced from other countries. They are harder to grow but they produce more fruit. Cultivated bananas may be quite different from traditional or village bananas. They may be genetically different. They may have higher yield than village bananas if they are fertilized and cared for properly.
Table 1. Differences between traditional and cultivated bananas.
Traditional bananas Cultivated bananas
Many hundreds of varieties Few varieties, (cultivars), e.g. Cavendish, Gros Michel, Lady Finger
Can grow on poor soils Need good soils
Are easy to grow Can be difficult to grow
Get less pests and diseases Get more pests and diseases
Better taste Not so tasty
Some have no fruit All have big fruit
Some have red juice None have red juice
Some fruit contain seeds No fruit contain seeds
Leaves stiff and grow upright Leaves hang down
Smaller plant, not last a long time Larger plant, lasts a long time
Smaller fruit bunch, some upright Larger fruit bunch, all hang down
Leafy bracts over fruit red underneath Leaf bracts over fruit yellow underneath
Few black marks on a false stem Many black marks on a false stem
Canal through the petiole closed Canal through the petiole open

1.2 Varieties of bananas
Bananas may have originated in Malaysia but in 327 BC Alexander the Great took some back Europe. Arab people took them to Africa and Spanish or Portuguese people took them to North America. In Australia, about 95% of the bananas are the "Cavendish" variety, named after the British Lord Cavendish who grew them in Kew Gardens, London. The red tip or eco-bananas is a variety of Cavendish grown with a minimum of chemicals and the ends dipped in hot red wax. The smaller, sweeter "Lady Finger" bananas represent 4% of the market. A similar variety is "Goldfinger". An interesting variety, "Ducasse", has superior flavour to other varieties and keeps its shape during cooking. However, the soft skin is speckled with a grey white mould and by the time the banana is ripe the skin is black.

1.3 Banana language
Debelling is cutting off the banana flower, called the bell.
A finger is a single banana fruit
A finger stalk is the stalk attaching the finger to the hand
A hand is a cluster of bananas from a single flower group at a node forming a section of the bunch because bananas grow in layers around the stalk
A bunch is the whole flowering stem, (inflorescence), bearing hands of several fingers of fruit. So a bunch with nine layers of bananas is called a nine hand bunch. When marketing bananas, a bunch is called a stem.

2. Leaf
See diagram 51.2: Leaf
You will need a banana leaf in the classroom, or take students outside to see a banana plant.
Draw a whole banana leaf and include the following four parts:
1. The large flat leaf blade, the lamina, that has many small veins that run close together.
2. The thick strong middle of the leaf, the midrib.
3. The strong leaf stalk, the petiole, that holds the leaf up to the sun.
4. The thick elongated part of the leaf stalk, the leaf sheath. The end of the leaf sheath is the leaf base.
A leaf will stop it making food by photosynthesis if: 1. strong winds blow the leaf off the plant, 2. the leaf is eaten by insects or other animals, 3. the leaf is killed by a disease, 4. a creeper or vine grows over a leaf and stops the sun shining on it.
The leaf edges may tear or break in a strong wind. This does not hurt the leaf much. When a leaf is old, it may have many breaks in it.
The banana leaf is designed to tear along the veins. Three is some evidence that photosynthesis by the leaf increases after mild tearing and the parts of the leaf are flapping in the wind. However, severely torn leaves may cause desiccation of the plant.

3. Leaf growth
See diagram 51.3: Growth of banana plant
You will need a banana plant in the classroom, or take the students to see a banana plant.
The banana plant needs 8 to 9 green leaves before it will make the flowers that turn into the fruit. New leaves are made as the older leaves die and hang down. Note the number of leaves on a banana plant. Record the length and width of some big leaves. The banana "tree" is really a collection of big leaves. The leaf stalks, petioles, of the leaves wrap around each other to form a false stem, pseudostem. The real stem and roots are underground. The youngest leaf grows up through the middle of the plant. At first, the leaf is rolled up but later it opens and hangs down. Later, a flowering stem, inflorescence, grows up from the underground item. The flowering stem grows out the top in the middle of the plant, turns down and produces flowers and fruit. After the flowering stem appears, no more leaves can grow. From the underground stem buds grow to form new shoots, suckers. Suckers grow to form the next "trees".

4. False stem, (pseudostem
See diagram 51.3: Leaf bases
You will need an old banana stem that has died or a stem from which the bunch of fruit has been cut. Use an axe or a bush knife to cut off a piece of this stem about 30 cm long. Be careful! Spiders and other animals that can bite you may be living in the false stem!
The "stem" is really a collection of leaf bases wrapped around each other, so it is a " false stem", (pseudostem). It is the "trunk" of the "tree".
Draw the cut end of a stem. See the leaf bases wrapped around each other. Take off the leaf sheaths or leaf bases one by one until you can see there is no stem inside. You may see a small hard piece of the flower stalk in the centre.
5. Corm
See diagram 51.5: Banana corm, (VS, vertical section)
You will need a corm of an old banana plant
The true stem of the banana plant is an underground stem, a rhizome. The thick part is the corm. The corm makes shoots that grow into branches or other corms. New plants come from these shoots. The branches and suckers grow very close together to form a clump, a rootstock with many shoots. It is difficult to see the shape of the corm so cut off a piece of corm by putting a spade or a bush knife between a strong sucker and the side of the main plant. Wash it and cut off some roots. Compare your cut piece of corm with the diagram. Suckers grow from the dormant buds, ("eyes"), on the corm. Note that each sucker formed is higher than the corm it came from so plant suckers deeply in the soil. If the land is sloping, the suckers are usually formed on the uphill side. If left alone, generations of banana plants will gradually move up a hill.
6. Roots
Just before the class, you will need to cut off a piece of corm with roots.
The roots of the banana plant are shallow, not deep in the soil. The plant can be easily blown over by a strong wind. Do not dig deeply close to the plant because you may cut the shallow roots. Cutting off weeds with a bush knife is better than trying to dig them out deeply and damaging the roots. Roots near the surface of the soil may become dry if there is no rain. So use as mulch dead leaves and dead grass on top of soil to keep the surface soil moist. Dig around the growing corm to find some shallow roots.

7. Inflorescence, (flowers)
See diagram 51.7.1: Inflorescence | See diagram 51.7.2: Flowers, male | See diagram 51.7.3: Flowers and fruit
See diagram 51.7.4: Banana berry
You will need a banana plant with fruit on it. If there is no fruit ready to see, teach this later when the fruit bunch is growing up.
The axis of the flowering stem, inflorescence, is the stalk. The flowers are covered by purple bracts, small leaves or leaf scales that lift then shed as the flower grows. The flowering stem before the bracts have lifted is the "bud". Individual flowers appear and develop from bisexual flowers to male or female flowers by losing their male or female organs. The female flowers develop into the clusters of seedless fruits without need of pollination. The male flower is at the end of the stalk, with a thin leaf like covering, is the "bell", ("flower", "navel"). The female flowers further up the stalk become banana fruit. When the fruit is very small, it is angular and does not have much stored food inside. The usual stage for cutting for transporting some distance to market or for export is green fruit with the
angles still just showing. When the angles have disappeared, the fruit is at the " round full bunch" stage and should be eaten soon.
8. Choosing a site
4.26 Leucaena leucocephala
Discuss the site for a banana project with the school principal, local community and a field officer of the Ministry of Agriculture. Prepare to first take the students to several unsuitable places then take them to see the place you have already chosen for planting the bananas.
1. The banana is a tropical plant and benefits from moderate heat, adequate moisture and protection from wind. Bananas flourish best when they receive full sunlight for most of the day. A warm sheltered spot with a north to easterly aspect protected from cold westerly and southerly winds should be selected. The minimum temperature for growth is 14°C. Frosts will kill the leaves and sometimes plants. Periods of cold weather with temperatures below 13°C will cause chilling injury to fruit. The fruit then develop a dull appearance. The leaves of plants affected by cold conditions, (< 10°C to 12°C), can turn yellow and bunch size is reduced.
2. The place you choose for the banana project should have the following properties: 1. Be near the school, on flat land or land sloping towards the North, 2. Water table is not too deep because you will plant about 1 metre above the water table, 3. Sunny all day, not shaded by big trees, 4. Sheltered from strong winds, e.g. sheltered but not shaded by buildings or trees, 5. Annual rainfall more than 1200 mm during 12 months, 6. Deep soil with plenty of plant nutrients, not sandy soils or clay soil, 7. Soil pH between 5 and 6
3. Choose land that has not grown bananas for two years to avoid by pests and diseases left behind by the old banana plants. Do not use land that has wild bananas growing on it or where there are dead banana plants.
4. Clear the bush two months before planting but leave some trees on the windy side as a windbreak, or plant Leucaena. On the flat land the bush should be burnt but this may cause soil erosion from rain on sloping land so leave some plant cover there. Plant a cover crop to protect the soil and shade any grass and weeds, e.g. cowpea, pigeon pea, velvet bean, Crotalaria, Pueraria. Plant at least 4 m apart, but planting distances depends on the fertility of the soil and on the size of the variety. Ask the Ministry of Agriculture for advice on planting distance. Plants should be grown closer on fertilized or richer soils and further apart on unfertilized or poorer soils.
5. In some places you are not allowed to plant bananas near houses or dormitories because some people say they attract mosquitoes.
On atolls, the side of an old pit for swamp taro, (Cyrtosperma), is a good place or you can dig a special planting hole in another place. You may find a suitable place sheltered by coconuts, or by a house, or by bushes on the lagoon side of an atoll. The exposed windy side of an atoll near the ocean is not a good place.
6. Banana plants grow best in well drained, deep soil that has good moisture retention and is rich in plant foods and organic matter. Light sandy soils require considerable mulching to improve water retention, and nutrients are quickly leached from this type of soil. Although bananas like ample water, they will not tolerate waterlogging. Roots start to die after an hour in flooded soils.
Examples of planting distances
Variety and distance apart on the square Dwarf Cavendish 2 m Giant Cavendish, Mons Mari, Williams 3 m Lady Finger 4 m
9. Preparing ground
See diagram 51.9: Make planting holes
You will need digging tools, bush knives, compost, fine black soil, dead leaves, coconut husks. Get advice from the Ministry of Agriculture about using chemical herbicides for preparing ground, e.g. glyphosate weedicide.
Clear the land around the planting places, cutting down weeds and bushes. The ground should become "clean weeded" no weeds at all. Dig the holes about 3 - 5 m apart and 60 cm or 2 spade blades deep and wide, or 300 mm square and 250 mm deep. Fill the bottom of the planting hole with coconut husks and dead leaves and some fine sand. They must push the sand down into the spaces between the husks so the soil is quite firm.
Fill with rotten compost and legume cover crops such as cowpea or Crotalaria. If you leave the holes open, make sure that people do not fall into them. On top of this put a small heap of compost mixed with fine black soil. The planting material will be planted into this soil and compost mixture. Add some pig manure or sprinkle a matchbox full of mixed fertilizer.
10. Planting material
See diagram 51.10: Planting material
You will need a large plant to show how to cut off the different kinds of planting material. Try to obtain planting material from agricultural officers. The planting material must be clean. It should not have any holes or spots on it due to insects or disease.
The different kinds of planting material, sets:
1. Pieces of corm, ("bits"), each have a bud, ("eye"). A bit is a piece of the rhizome or short underground stem of the plant trimmed to a single mature bud or eye. To obtain bits for planting, select a well grown healthy plant that is at least 6 months old and has not bunched. Remove the plant roots from the rhizome, split the rhizome and attached pseudostem, (plant stem), in sections in such a way that each piece has a prominent centrally placed eye. Bits must be planted in the soil the same way up as it was when cut off. Bits grow slowly.
2. Get a whole banana plant and identify the different kinds of suckers. Cut suckers away from the mother plant by pushing a spade or knife down between the sucker and the main stem. A sucker is an offshoot from the parent plant. The best suckers are about 45 to 60 cm tall, or up to 1 metre high and at least 15 cm across, and have narrow "sword" leaves. Small suckers with spindly stems and broad, flattened leaves lack vigour and should not be used for planting. Suckers with broad leaves, "water shoots", are useless for planting and should be removed and burnt. If small suckers, "peepers", must be used for planting material, they must include a piece of corm at the bottom.
3. To transplant larger suckers, cut off all but six of the large green leaves.
4. For trimming the suckers, use a large with a sharp knife to remove the roots so that you can see the white corm. Use a small knife to cut out any red brown spots or tunnels caused by pests. Work quickly because the cut corm will darken in the air so you cannot see the spots.
5. Store the planting material in a shady, dry place, e.g. under a house. Leave the suckers there for four days until the cut surface of the corms have healed over. If the sucker is planted soon after it is cut off, the corm may rot and die.
6. To avoid pests and disease, use tissue-cultured plantlets from accredited nurseries that meet strict pest free and disease hygiene standards.
7. Draw the different kinds of planting material.

11. Planting
See diagram 51.9: Planting
1. In southern Queensland, the best time to plant is from September to  mid December when rain is more common. Bananas are usually planted at the beginning of the wet season but can be planted all year round.
2. The bunch of fruit will be ready for harvest in about 12 months. The first crop after planting is the "plant crop". Later crops from the suckers are the "ratoon crops".
3. When planting, dig a hole about 300 mm square and 250 mm deep. Place some well composted poultry manure and loose soil in the hole, and then insert the planting piece so that the junction of the corm and pseudostem of the sucker or bit is about 150 mm below the soil level. On sloping sites, the eye should be placed on the uphill side. The hole should then be filled with soil and tramped down firmly.
4. Make a hole in the heap of good soil and compost in the middle of the planting. Hold the top of the sucker when you have put it in the hole. The bottom of the sucker should be 12 cm below the soil surface. Fill in the soil around the sucker. Put more soil around the stem. Put dead leaves on top of the soil all around the sucker. Make sure there is a hole at the top of the planting place so that rain and water will run down to the sucker. Tread on the soil around the sucker to make the soil firm. Water the soil around the sucker.
However, water should be applied sparingly after planting until the plants begin to grow. If too much water is applied during this period the planting piece may rot.  Plants are usually spaced 5 m apart.
5. Plant one sucker first as demonstration then students plant the other suckers.
6. Avoiding planting in hot, wet weather to avoid rotting in the planting material.
7. During dry weather plant small suckers or bits in bags or pots and water them every few days for the first two weeks until the root systems are established. These potted plants will be stronger and will establish more quickly when they are planted out in the banana garden.
8. Before planting,  the land must be well prepared to ensure food soil contact well and have good drainage as from deep ripping. .
9. If suckers and bits are planted in moist soil in the days after good rain, no more water is needed until the shoots emerge. However, in dry areas  apply 25 - 50 mm of irrigation soon after planting.
10. Larger planting pieces give better strikes, however the larger pieces have more than one "eye" so the emerging extra shoots must later be cut out.
11. Leave cut surfaces to air dry for 1-2 days in the shade and form a seal, to avoid cut surfaces on suckers and bits being infected by soil organisms and rot. Keep soil away from the cut surfaces.
12. Plant suckers at 15 cm of soil depth to ensure adequate soil moisture until shoots emerge. After covering suckers or bits, firm down the soil with the foot, to improve contact between soil and the planting material.

12.0 Plant care
See diagram 51.3: Generations 1 to 3
Encourage students to visit the banana project each day and note any problems. Get advice from the Ministry of Agriculture about using chemical herbicides for weeding, e.g. glyphosate weedicide.
Take the students to see some growing bananas. Show them different ways to care for bananas and ask them why they should be done. In some places it is not the custom of the people to do all these things. The people may feel that the plants can look after themselves. However, commercial banana growers say that in the first three to four months, bananas need lots of care, soil moisture and fertilizer for the best growth and fruit production. This will increase the weight of the first bunch and how many "hands"
the banana will have.
12.1 Bunch covering
Bunch covers are made of blue plastic. They let the fruit ripen evenly and protect the fruit from insects, flying foxes, tree rats and birds. Cut a hole in the bottom to let the water out. Place the blue plastic bunch cover around the bunch of fruit when the last hand is visible. Bunch covers help to increase the weight and improve the quality of the fruit by avoiding blemishes. Also, the bunch cover may hold in ethylene close to the fruit to accelerate fruit ripening. Bunch covers protect the fruit from bird, wind and sun damage, improve its quality and increase the yield. However they can encourage other pests such as rats to create nests within the bunch. 

12.2 De-suckering
See diagram 51.13.1: A stool of bananas | See diagram 51.13.2: Different types of suckers
See diagram 51.13.2.1: Cycles of suckers
The best way to teach the importance of this procedure is to take students to see stands of bananas that have been de-suckered and stands that have not been de-suckered. Alternatively you could set up a trial where you divide your banana project into two and de-sucker only half the bananas to show the difference in yield.
If the banana plant is just left alone, it will soon be surrounded by many suckers. These suckers will compete with the mother plant for water and plant food and so the fruit formed by the mother plant will be very small. All the useless suckers should be cut out before they get too big. If you do this, you will have a "stool" or group of bananas that never has more than four plants in it:
1. One large plant one bearing fruit, 2. One smaller plant but the next to bear fruit, 3. One medium-sized sucker, and 4. One small sucker.
To make sure that have only one or two strong suckers for the next generation, allow only one new sucker to grow every three months. Two strong sword suckers should be selected to bear fruit for the next crop. One of these can be allowed to grow for the new crop, ("follower crop"). The other can be cut out for planting in another project. The other suckers should be cut out after they are more than 30 cm tall.
Use a sharp knife to cut the unwanted suckers off at ground level, scrape out the remains of the sucker and pour in a teaspoon of kerosene. It must be done when the suckers are very small. Cutting the tops of the suckers is useless because they will just grow again. The whole sucker and its bit of corm must be cut away from the mother plant. De-suckering must be done each month. Some village people refuse to de-sucker their bananas because they may not bother about it or they believe that they should not like to kill things if there is no need to do so. How would you explain to villagers about the need for de-suckering? You could say that having lots of suckers is like having too many chickens feeding from one small tin.
As the parent plant grows, it will produce several suckers around its base. It is important to allow only one of these followers to remain, but two suckers may be left on each parent if the planting is very vigorous. After the desired follower has been selected, all other sucker growth arising from the parent plant should be removed as soon as possible after it appears.
The easiest way to permanently remove unwanted suckers is to cut them off at ground level with a sharp knife. A small hollow should then be gouged in the centre of the cut surface with the point of the knife and a teaspoon of kerosene should be poured into the cavity. This kills the sucker. The follower should be selected when the parent is about three quarters grown in the spring or early summer.
12.3 Fertilizing
You will need fertilizers or coconut husks for mulch. Ask the Ministry of Agriculture for advice on fertilizing bananas because suitable application of fertilizers depends on climate, variety and soil type.
Bananas are "heavy feeders". They need a lot of potassium, K. To get a good size of bunch fertilize early and often. During the first third of the growth cycle, the size of the bunch is already determined based on the amount of fertilizer, water and heat of the soil. Bananas need heavy applications of fertilizer near the surface of the soil because of its shallow roots.
For high yield, quick growth during the first 3 months to get the largest possible leaf area is necessary. However, top dressing with fertilizer after 6 months is not desirable.
Each plant needs about 2 kg of mixed fertilizer each year, but this must be put on a little at a time, not all at once.
The fertilizer must not be put too close to the plant. It should be spread out evenly in a circle 1 metre wide around the stem of the plant. Sprinkle 0.25 kg of mixed fertilizer on the ground around each banana plant. There is no need to dig it in, just sprinkle it over the leaf mulch. If you do not have any fertilizer, put many coconut husks on the soil around each plant. Put the husks with the cup upwards. Husks contain some potash plant food and the rain will wash this wash this into the soil. Put some pig manure around the plants if there is no fertilizer, but the NPK fertilizer is best to use. Pull out any weeds that are growing near the plants.
On sloping sites, apply the fertilizer to the up hill side only.
Different fertilizing methods
In some places, farmers feed the bananas NPK 6-2-12 each week and feed magnesium every two months. Others use a 5-5-5 all purpose organic fertilizer mixture with additional sources of potassium.
A complete fertilizer with an analysis of approximately 10% nitrogen, 2% phosphorus and 22% potassium, that is, a 10:2:22 NPK mixture, is quite suitable for use on most of the soils bananas can be grown in. As soon as the sucker begins to grow, or the shoot from the bit appears above ground level, the first application of fertilizer at the rate of 200 g per plant can be made. Subsequent dressings of the same fertilizer at twice the rate are applied every 4 to 6 weeks during the growing season. A similar fertilizing program should be followed in subsequent years over the period of September to April. Applying a dressing of dolomite at 200 g per square metre every year is beneficial to the plants. This material should also be spread evenly over the soil.
After the first crop is harvested, it is recommended that you apply, per banana plant per year, a total of 800 g of agricultural lime, 240 g of urea, 30 g of superphosphate, 600 g of potassium sulfate.
For better results, apply a quarter of the recommended application four times between September and April. Alternatively, apply organic fertilizers.
What are the advantages of using fertilizers? Why is it not the custom of the people to use them? Can you do a field trial to compare the yield of banana plants with fertilizer with the yield of plants without any fertilizer?
12.4 Mulching and watering
Mulching retains moisture, cuts down on weed growth, and helps the plant absorb the fertilizer better. Make mulch by chopping the older banana leaves, banana stalks and plants harvested and cut down. The composted banana leaves and plants will add potassium to the soil. Use discarded parts of banana plants as long as they do not have pests or diseases attached to them. Also, use well-rotted manure, straw, lawn clippings. However, the mulch should be kept at least 50 cm from the base of the plant. This practice should deter the banana weevil borer from attacking the plants and possibly reduce the incidence of fungal diseases.
Watering
Give the plants water especially when they are young and when there is no rain.
12.5 Propping
Propping is to place a prop under the stalk of a hand of fruit because sometimes the bunch is too heavy for the plant. Place the prop after the last hand of fruit has formed. Props can be made from two poles crossed about 50 cm from each end to form an X shape and bound together with wire where they cross. Then place the shorter upper side of the X under the banana stalk to allow the bunch to hang down so that the stalk is not squeezed and conduction of liquids occurs normally through it.

12.6 Trashing and debelling
Trashing is the cutting down of all dead leaves because they may have pests and diseases living in them. Cut them down with a bush knife and burn them. Cut with an upward stroke of the bush knife.
It is extremely important that dead and diseased leaves are cut from the plant regularly. This practice will reduce the incidence of leaf diseases, lower the fire risk, and help to keep the plants tidy, but care should be taken to remove only leaves that are diseased or completely dead.
Debelling is to cut off the banana flower, the "bell", when the last row of bananas has formed because the flower continues to use some nutrients and the bell makes the bunch much too heavy and may attract birds. Cut bell 100 cm from the last hand when the last hand has set. You can eat the infertile flowers inside the flower petals.

12.7 Weeding
Weeds compete for water, nutrients and light, and may allow pests and diseases to be near the bananas and attack them. During the first year of growth, chip away weeds and grass between the plants with a hoe. The ground in the banana project should be weed free but if the manual weeding is done carelessly with a hoe the shallow roots of the bananas will be damaged. Plant a cover crop to control weeds. You can also use clean mulch to control weeds, but make sure that there are no insect pests in it.

13.0 Pests
See diagram 51.15: Insect pests of banana
Ask the agriculture field officer about pests and diseases of bananas in your area and show the agricultural officer any infected plants from your banana project. Look for signs of pests and diseases in the school banana project and in other banana projects. Insect pests of banana may include Banana aphid, Banana flower thrips, Banana fruit caterpillar, Banana rust thrips, Banana scab moth,
Banana weevil borer, Banana silvering thrips, Banana spotting and  fruit spotting bugs, Cluster caterpillar, Fruit piercing moths,
Queensland fruit fly, Spider mite, Two spotted mite, Spiralling white fly, Sugarcane bud moth.

13.1 Banana root nematode
Banana root nematode, burrowing nematode, worm or eel worm, Radopholus similis
This nematode worm lives in most banana growing regions. The tiny worms make red brown tunnels in the banana roots and corm. A fungus, Fusarium oxysporum, infects the tunnels causing root rot or blackhead disease. The roots rot and weaken the plant that may topple over in strong wind after the heavy fruit bunches have formed.
For control of Banana Root Nematode
1. Select clean land and keep land clean of weeds, dead leaves and trash. The ideal is to use ground that has not grown bananas, Sudan grass or stylo for at least three years. Nematodes are spread by water and the damp dirt sticking to farm implements.
2. Select clean suckers for planting material.
3. Plant in land that has a well grown cover crop, e.g. cowpea, pigeon pea, velvet bean, lablab, Crotalaria, Pueraria, Calopogonium, Rhodes grass, (Chloris gayana)
4. Do not plant bananas near crops that may have nematodes in their roots, e.g. corn, (maize,) sugar cane, Siratro, green panic grass, sorghum and many varieties of legumes.
5. To prepare planting material, cut off all roots, soil and traces of discoloured tissue in the corm, discard any corms with borer tunnelling activity, remove the tissue where outside leaves emerge from the corm. Then dip this pared material in 53°C to 55°C hot water for 20 minutes, dry in the sun, then plant straight away. It is not easy to judge how long to keep the planting material in the hot water to kill any nematodes but not cook the corm. Use 0.7 to 0.9 kg bits with backward eyes because bits with advanced eyes are difficult to pare properly and may not survive heat treatment.
6. Treat planting material with a chemical that kills nematodes, nematicide, e.g. DBCP and treat infected soil with a nematicide.

13.2 Banana weevil borer, banana root borer, "banana beetle", Cosmopolites sordidus
Banana weevil borer can be the most serious pest of bananas. The weevils are about 10-12 mm long, with a long weevil snout, and are brown then black in colour. The soft, white, legless larvae have a curved body, are swollen in the middle and a hard brown head. The structure of the future weevil can be seen through the white skin of the pupae, the same size as the larvae. They seldom fly, move slowly and pretend to be dead when disturbed. So their natural spread is very slow and their dispersal is usually caused by the use of infested suckers and bits for planting.. They live in rotting false stems lying on the ground. At night they burrow into the corm above ground and lay white eggs, which hatch out larvae. The white larva bores many round tunnels in the corm that let in fungi that can cause the whole corm to rot and the plant dies. An average life cycle is completed in 12 weeks in north Queensland but the adult weevils live a long time.
For control of Banana weevil borer: 1. Select clean land and keep land clean of weeds, dead leaves and trash. 2. Select clean suckers for planting material. 3. Make weevil traps with cut pieces of corm placed cut side down on a small stone. Weevils will live under the piece of corm. These weevils can then be collected every few days and killed.
When replanting into old banana land, all banana residues must be destroyed and the land left to fallow for at least six months after all residues have rotted down to prevent carry over of adults. Ensure good plantation hygiene by removing all trash from the area around plants and suckers by raking all leaves into the inter row. Cut up all fallen and harvested plant pseudostems to increase the rate of breakdown and destroy breeding sites. Chemical control is possible if supervised by an officer of the Department of Primary Industry.
13.3 Banana scab moth, Nacoleia octasema
The moth is small, (25 mm wingspan), tan to light brown with small black spots on the wings. The flattened eggs are laid in clusters ranging from a few to 30 eggs. The eggs resemble shiny overlapping fish scales. The yellow to orange larvae grow to about 25 mm before pupating. Eggs are laid on or near to an emerging bunch and hatch after about four days. The larvae feed on young female flowers and young fruit leaving a scab. As the bracts and hands of bananas lift from the bunch stalk the larvae move to the next closed hand. The life cycle egg to egg is completed in 28 days. Adults live for only 4-5 days. They hide in trash during the day and mate and lay eggs in the early evening. Pandanus and heliconia are known alternate hosts so they should not grow near the bananas. The scars caused by the larval feeding form a black callous so people do not like to buy or eat the fruit. Control by clearing away any dead plant material around the plant base. The scab moth has many natural enemies, e.g. spiders, so do not use chemicals that can kill these natural predators.

14.0 Diseases
See diagram 51.16: Diseases of banana
Diseases of bananas may include Bunchy top, Panama disease (Fusarium wilt), Black sigatoka (leaf spot), Banana bract mosaic disease, Banana leaf spot diseases, Banana freckle, Anthracnose, Choke throat, Rhizome soft rot
Ask the agriculture field officer about pests and diseases of bananas in your area and show the agricultural officer any infected plants from your banana project. The usual advice from an agricultural field officer is buy only clean planting material of approved varieties, report any unusual disease symptoms, keep leaf disease under control and observe the quarantine requirements of the Ministry of Agriculture.
Quarantine regulations vary depending on where you live and the type of banana plant movement.
Look for signs of pests and diseases in the school banana project and in other banana projects. Most diseases are caused by fungi that can live in the air as tiny spores, or be carried on diseased leaves. They can usually infect the plant in the rainy season when the spores germinate and the fungus can then grow into the leaf through the stomates. Another pathway of infection occurs when fungi and bacteria enter holes in the leaves, stem, corn and roots made by insects, nematode worms or other animals.
Methods for control of diseases include: 1. Select clean land with no wild bananas. 2. Keep land clean of weeds, dead leaves and trash. 3. Select clean suckers for planting material. 4. Plant in land that has a well grown cover crop. 5. Keeping the project clean of weeds, dead leaves on the ground, dead leaves hanging down from the plants. 6. Control rats and flying foxes. 6. Use your own planting material if you know that your bananas are free of pests and diseases. Planting material from other places may contain pests and diseases.
14.1 Bunchy top
Bunchy top disease can cause significant loss of production. The banana bunchy top virus, (BBTV), occurs world wide and causes a characteristic "bunched" appearance of newly emerging leaves, reduced plant growth and dot and dash flecks along leaf veins and underside of leaves. Infected leaves may be more upright with pale yellow margins. Infected plants do not produce fruit. BBTV is spread in infected planting material, including suckers or bits, or by the banana aphid, (Pentalonia nigronervosa). Bunchy top cannot be cured and infected plants must be destroyed. Infected plants and all trash must be burned.
14.2 Panama disease, (Fusarium wilt)
Panama disease, (fusarium wilt), is caused by the soil fungus Fusarium oxysporum, which spreads with soil and water movement, and also with infected planting material.. The first symptoms are yellowing and dying of the leaf edges, often mistaken for effects of water stress. The leaves later collapse until the plant has the appearance of a stump with a skirt of dead or dying leaves. Internally, the water conducting tissue is discoloured. The fungus enters through the roots especially if damaged by nematodes. The plant cannot take up water and the leaves wilt. The cut stem has a fishy smell. There is no sanitary control or chemical control available, but the "Cavendish" clones are highly resistant to this wilt. Effects range from reduced yields to death of the plants. The soil remains infested indefinitely so that only resistant varieties can be grown on that site in the future. There are four races of the fungus. Race 1 attacks Lady finger, Sugar and Ducasse bananas but not Cavendish bananas. Race 2 attacks Bluggoe and Blue Java bananas but not other banana varieties. Race 3 attacks only Heliconia and is not a problem on bananas. Race 4 attacks nearly all varieties of bananas, including the main commercial Cavendish variety.
Bacterial wilt, moko disease, is transmitted above the ground by insects or infected knives is similar to Panama disease except that it shows yellow lamina near the petiole. It can be controlled by burning diseases plants and disinfecting knives with formalin.

14.3 Black sigatoka disease
Black sigatoka, (leaf spot, black leaf streak), disease, is caused by Mycosphaerella fijiensis. It occurs in most banana growing regions. They cause the bananas to produce less fruit by destroying the leaves. Black Sigatoka disease starts as yellow steaks or 1 mm red brown flecks on the lower leaf surface that increase in size to form dark brown linear or elliptical streaks, 4-12 mm long, parallel to the leaf veins and visible on both leaf surfaces. The streaks expand becoming elliptical spots often with a distinctive yellow halo. As the lesions mature further, they become sunken and the centre turns grey. In susceptible cultivars, high levels of disease can cause large areas of the leaf surface to die. The disease can be spread by the movement of infected plant material, fungal spores produced on leaf lesions, within dead leaf material on the plant, in trash and by spores dispersed by the wind or by water splash. The unfurling and youngest fully expanded leaves on large plants and suckers are the most susceptible to infection. As the leaves mature, they become resistant to infection. Severely infected leaves can die, significantly reducing fruit yield, and causing mixed and premature ripening of bunches. The disease spreads rapidly in hot, wet and windy weather if the banana project is not clean weeded and useless suckers not removed. Badly infected leaves should be removed and burnt. Fungicide spraying and use of fogging with mineral oils will help to prevent this disease.
Researchers at the Biotechnology Research Centre, (CIBE), Ecuador, have isolated the genes in the naturally resistant banana variety Musa Calcutta-4 to develop a protocol for the genetic transformation of banana cultivars Williams and Oritoas well as plantain cultivars Barraganete and Dominico cultivar.

14.4 Comparing bacterial wilt and fusarium wilt
Comparing banana bacterial wilt caused by Xanthomonas campestris and fusarium wilt, caused by Fusarium oxysporum,  by Richard Davis, Plant Pathologist
Bugtok, (Tibagnol), is caused by a bacterium Pseudomonas solanacearum, carried by rasping, piercing and sucking insects.
Moko disease, is caused by Ralstonia solanacearum, a proteobacteria, is soil borne and causes bacterial wilt.
Blood disease is similar to Moko disease, the cause is not certain
Panama disease is caused by the soil borne fungus, Fusarium oxysporum  formerpecialis (f.sp), cubense, (FOC), which infects susceptible bananas through the roots causing a lethal vascular wilt.
 1. Leaf symptoms
Blood disease and Moko disease: Leaves show a transient yellowing. Wilt and die and hang down. Eventually. a 'skirt' of dead leaves remains around the pseudostem.
Xanthomonas wilt: Young leaves become yellow and die.
Compared to fusarium wilt: Wilt development is generally slower. so many leaves remain upright and rigid for much longer before they eventually die. They become a characteristic bright yellow, which is easy to see from a distance.
2. Presence of a bunch
Blood disease, Moko, Bugtok: As infection through the floral raceme is common, a bunch of fruit is often seen in diseased plants.
Compared to fusarium wilt: Infections with most stains of Foc usually get too severe too early for a bunch to be produced.
3. Fruit symptoms
Blood disease: Fruit is outwardly unaffected but internally is discoloured and may contain dry cavities or pockets of reddish brown mucoid tissue.
Moko: The fruit turn yellow and when cut show a firm brown rot that becomes grey.
Bugtok: Fruits of infected plants are internally discoloured red or brown and remain hard even when ripe.
Xanthomonas wilt: Fruit ripen unevenly and when cut, show a red brown internal rot.
Compared to fusarium wilt: If fruit are present there will be no discoloration inside green living fruits.
4. Internal vascular symptoms
Blood disease and moko: Internally brown vascular streaking can be seen throughout the plant, especially towards the centre of pseudostems and peduncles, and also in roots. Cut vascular bundles exude bacterial ooze that is white to reddish brown  colour,  (blood disease) or cream, yellow to brown to black (moko disease).
Bugtok: Vascular discoloration also occurs, but because the  symptoms of bugtok are confined to the floral raceme, this does not usually extend far into the lower part of the fruit stem..
Xanthomonas wilt: Cut vascular bundles exude a yellow ooze.
Compared to fusarium wilt: Discoloration is readily seen in the pseudostem and would not occur in the fruit peduncles,  if present. Infected xylem vessels are seen as brown, red or yellow continuous vertical lines, which appear as rings in cross section. Early in the process, before secondary rotting becomes extensive, there will be little or no discoloration in the centre of the pseudostem. Later however, internal decay gets worse and brown secondary rotting
can be seen throughout.
5. Symptoms in suckers
Blood disease: Most suckers connected to the corm also become infected.
Compared to fusarium wilt: Suckers can often appear completely healthy and symptom less even though they are usually full of Foc microconidia.

15. Fruit bunch
See diagram 51.17: Bunch
Banana plants start to bear fruit after they have developed a certain n umber of leaves, 20 to 30 leaves, depending on the variety of banana. The fruit bunch appears at the top of the plant when it is about nine to ten months old. About 70 days after this the fruits begin to grow, and the bunch starts to get heavier. Two things need to be done when the bunch begins to develop: 1. Put a long piece of wood under the stalk of bunch to support it. If this is not done, a strong wind may blow the plant down. 2. Cut off the large bud of the male flowers about 15 to 20 cm below the bottom of the last flower. Do this two weeks after the first hand of flowers opens. If it is done earlier than this, the plant will lose too much sap. If it is done too late, much food will be sent down to this part that is not needed. Cut off the flower bell 100 mm below the last hand to increase fruit size.
16. Harvesting
See diagram 51.18: Packing bananas
1. You need a flowering stem with bananas.
Fruit develops about two months after the flowering stalk has pushed up. The flowering stem has grown up through the middle of the false stem turned down, and started to form two rows of flowers at each node, female flowers and later male flowers. The cluster of female flowers at each node will produce a hand of bananas. The male flowers are sterile and soon fall off leaving a bare stem. The end of the stem continues to grow even after the fruit has formed. Each cluster of female and male flowers is enclosed in a colourful bracket that is like a protective leaf. The young bracts at the end of the stem enclose each other to form a cone, ("the bell"). The older bracts further up the stem turn back then an off. Leave 45 cm of the stalk above the fruit. This is used for carrying the bunch easily. It also holds some water that he fruit can use after cutting. Never leave the fruit in the hot sun. Always handle fruit very carefully to stop
bruising and marking the fruit. Never let sea water touch the fruit. Bananas ripen best when they are picked green. If they are to be used for the home, cutting them down when they are fat is best, round and light green in colour. If they have to be taken in a truck or a boat to market, cutting them down when a little younger and the fruit are still a bit angular and not round is best. The fruit ripens best in a dark, cool place. Take great care should be taken in harvesting bananas. If the fruit has to be packed into boxes, the hands must be removed and packed neatly in layers in the box, first one way, then the other. A little bit of stalk must be left on each hand so that the fingers of each hand stay together.
A bunch is ready to cut when the fruit is fairly evenly rounded with no prominent ribs, and the dry remains of the flowers break off readily from the fruit tip in the fingers when rubbed. If the bunch is protected by an open plastic sleeve, it can be left on the plant until the fruit begin to ripen. When harvesting, the stalk of the bunch should be cut well above the top hand of bananas.
A bunch is ready to harvest when the fruit is full and round, the remains of the flowers should break off the end of the fruit when rubbed with the fingers. The fingers are plump, green and almost ready to turn yellow. Note the date when the first petal opens. Twelve weeks later, the fruit should be ready to be cut down. Use a bush knife to cut the bunch stalk high up to leave a long "handle". If the bunch is too high up, cut partly through the middle of the false stem to make it bend. Hang up the bunch by the false stem
in a shady place for ripening. Show the students how to cut down a bunch and hang it in the shade to ripen fully. Cut down the tree after harvest. The first generation tree will bear fruit once only then die to the ground so after harvesting there is no point in keeping the first generation tree. Cut the first generation tree down near to ground level and care for the follower crop in the same way as for the first generation crop. Show the students a flowering stem with bananas. Explain the different parts of the stem and the way the bananas are formed from the female flowers. Are the bananas ripe?
.Cut open a banana. Note the six sided fruit. Squeeze the banana and note the three parts of the fruit wall. The three rows of black spots are the remains of the seeds.

17. Ripening and handling
Remove individual hands from a green bunch to be ripened separately to have ripe bananas over a long period. Leave the hands to ripen in a cool, well ventilated place. Leave the blue plastic bag cover on the bunch, but open the bottom to provide some extra ventilation. The best ripening temperature is about 20°C. Above 26°C, the fruit softens and the pulp will ripens but the skin remains pale green. Fruit ripened at day temperatures 25°C to 28°C and night temperatures 17°C to 18°C are usually ready to eat in 2-5 days. Although some people prefer to use fully ripe bananas the quality and the flavour of the fruit are no less when harvested at the fully developed hard green stage and ripened later. The green unripe fruit produces heat and ethylene slowly then, as the skin colour changes from green to yellow, starts the ripening phase to quickly produce large amounts of heat and ethylene. To ripen bananas using ripening fruit, seal the bunch, hand or fingers in a plastic bag with a ripening, (not ripened), red apple or banana to absorb the ethylene from the ripening fruit. Leave the bag in a cool dark cupboard, but not in a refrigerator, for one day in summer or four days or more in winter. Then remove the ripening fruit but leave the bananas in the plastic bag. When bananas show the first signs of ripening, remove them from the plastic bag and allow them to ripen normally. Do not store bananas below 13°C so do not store them in a domestic refrigerator. However, bunches of green bananas stored at 13.3°C give off little heat or ethylene and so can be stored for about 2 weeks without ripening. Below 10oC, spoilage occurs when phenolic amines, e.g. dopamine, inside the vacuoles of banana skin cells, leak out and react with polyphenol oxidases and air to form brown polyphenols. Warming these bananas increases the skin browning.
Select a banana with a natural yellow white skin with no black patches. Put the banana in the refrigerator freezer overnight. The next day observe the banana still in the freezer. It is frozen hard and the same colour as the night before.  The oxidase enzymes cannot function at such a low temperature. Cover a plate with water to make a 0,5 cm layer of water over the plate. Remove the banana from the freezer and place it on the plate. The banana skin darkens before your eyes an the if you feel the banana it is soft inside. Pick up the banana a and observe its underside. It still has the same colour as the night before because the water on the plate did not allow oxygen to have access to the browning reaction. Put the banana on the table. The whole banana becomes black and squashy.

18. Uses of bananas
1. Bananas are a good source of dietary fibre, Vitamin C, vitamin A  and potassium. A banana may contain more potassium, calcium, phosphorus, iron, Vitamin A, thiamine, riboflavin, Niacin, and ascorbic acid than an apple! When harvested when the fruit is mature but still green the banana is mostly starch and about 1% sugar. As they ripen the starch converts entirely to sugar until when ripe they are nearly 20% sugar. Ripe bananas have a smooth  consistency and a characteristic smell caused by amyl acetate and other esters and eugenol. The acidity increases during ripening when they have a a dry, starchy texture. .Very ripe bananas are easily digested, which helps sick people and they are an excellent weaning food for babies when they stop drinking their mother's milk. Plantains,  (cooking bananas), have a high concentration of starched, so they must be cooked.
2. Prevent bananas from ripening too quickly by keeping them wrapped in a double sheet of newspaper in a cool cupboard. In very hot weather keep bananas wrapped in aluminium foil in a refrigerator to extend their shelf life. . If not to be eaten immediately, choose bananas with green tips. Solid yellow bananas are almost ready to eat and bananas with brown specks on the skin should be eaten immediately. Keep bananas at room temperature away from direct sunlight. The skin will turn brown black caused by browning enzymes and and phenolic substances, but the flesh will be unaffected. The ideal refrigeration temperature is about 13oC. If stored below 10oC, spoilage increases because of increase phenol levels from breakdown of cell membranes. To assist ripening of green bananas put them in a paper bag with an apple or pear. If using fresh bananas in fruit salads squeeze lemon juice over them to prevent browning. Use very ripe bananas in muffins or cakes. If using bananas in sandwiches, custards or fruit salads drop them in boiling water for a few seconds before peeling so that they will not turn black when used but will keep their original colour.
3. Bananas with a high sugar content are usually eaten raw. Bananas with high starch content, (plantains), are usually cooked.
Banana leaves can be used for wrapping fish, meat or chicken to be steamed, poached, grilled or barbecued. The stems and leaves can be used for plates, wrapping, umbrellas and cattle feed. The fibres can be used to make a batik cloth.
The banana blossom, (banana inflorescence), can be eaten after peeling off the outer leaves. It can be cooked in curries or soups. The male banana flower can be boiled and eaten as a vegetable. However, depending on the variety, the flower may have too high oxalic content and so are too astringent for most people.

20. Grow bananas at home
In some countries with a developed banana industry, it is illegal to grow bananas at home in the ground or in pots. You may need permission to up to a maximum of 10 banana plants or 30 pseudostems of approved varieties for a residential plantation. Residential plantations are defined as those bananas not grown for commercial purposes. Residential banana growers must comply with current biosecurity legislation. Only certain banana varieties may be allowed on residential plantations in certain areas.
Bananas grown in the home need bright diffused light, warmth, the right kind of food and attention once they are in fruit. In temperate countries, bananas are relatively free of pests. To grow bananas as an indoor plant, you need a sun porch, a greenhouse or a room with good light. Bees are unnecessary to produce fruit. Plant outdoors in the summer on a wheeled caddy, but drag it indoors before the first frost. Bananas are not frost tolerant plants. Temperatures below 0oC will kill off the foliage. Below 5oC the rhizome will die. Some non fruiting species, e.g. Musa basjoo, will take much colder weather.
Banana plants do well in the same narrow air temperature range that humans enjoy most. The optimum temperatures are between 20oC and 27oC. Below 20oC bananas may stop growing because the roots must be kept warm. Do not expose the plant to temperatures greater than 30oC. However, the plant will not die if it has sufficient water. Timing of fruit production is related to leaf output, so slowed growth from being too cool or too hot retards leaf emergence and delays fruiting. During high temperatures, plants in pots can be taken indoors.
The plant needs sun or other light on its leaves and warm roots. A dark  heat retaining pot and a gravel or black plastic mulch can boost soil temperature. Night time drops in temperature or low humidity do not seem to affect fruiting types of bananas but they take them longer to produce fruit. Fruiting bananas are seedless, so they reproduce either by rhizomes or suckers that sprout from the base of a mature stalk, called "pups". Tissue-cultured plantlets have been pathogen tested, making them ideal for use in residential plantations. These suckers are what you generally get when you purchase banana plants from nurseries. They should be planted soon after purchase. The most suitable planting mixes generally have the sandy loam quality that bananas like best. Start planting in big container, or plan on potting up within three months. These are fast growing plants that ultimately need at least a 15 gallon size container. Choose a dwarf variety, e.g. Dwarf Cavendish, about 4 feet at maturity and is recommended for indoor planting.
Bananas are heavy feeders, with potassium and nitrogen the key nutrients. Combine a good organic 5-5-5 fertilizer with a generous side dressing of a natural potassium source, e.g. kelp meal. Mix about 1/3 cup of the organic 5-5-5 when first planting the banana in 20 litre container, then add more when potting up into a 55 litre container. Feed generously during the warm weather months. Container grown bananas planted in potting soil should be fed small doses of organic fertilizer with every second watering. There is a direct correlation between nutrient availability early in a young banana plant s life and the number and quality of fruits produced. Bananas can be burnt by over fertilization with chemical fertilizers.
Never let a banana in a pot to dry out. For bananas in the ground, water at least once a week in extremely hot weather.
Cultivation is the same as growing banana plants in the ground: After all the fingerling bananas have formed, cut off the huge maroon flower otherwise it will sap energy that is better used to develop fruit. Support the fruiting stalk by propping it up with two pieces of crossed bamboo or lumber to leave the fruiting stalk hanging down. To speed ripening, cover the bunch with a white or blue plastic bag. Keep offshoots, or pups, down to one or two in the pot along with the main stalk. After the plant has fruited, discard the stalk that bore the bunch and cut off the pups, leaving any roots attached, then re-pot each individual remaining chunk with fresh soil.
Ripe bananas will have achieved a full colour and will have rounded out between the longitudinal ridges of the skin. Immature bananas have an angular look. You can finish ripening them in a bag with an apple. However, if the fruit starts to split harvest them immediately without waiting for the full colouring. You can remove one hand at a time to test for maturity without using a whole bunch. After harvest cut down the stalk about 100 cm above the ground to avoid a crowded forest of non producing plants competing for nutrients. Banana behaves like a tropical weed. Some growers cut down the fruiting stalk with the fruit still attached to save the work of climbing a ladder and lowering a heavy bunch. When cutting the stalk, remember that juices from the cut may cause a brown stain on clothes and may irritate the skin.
Preface
Before teaching this project, discuss the content of the lessons with a field officer of the Ministry of Agriculture and get advice on planting material, planting distances, a site for planting, approved mulch, composting, and control of pests and diseases. Use only the procedures, agricultural chemicals and insecticides recommended by the local field officer of the Ministry of Agriculture. If you cannot control insects by hand-picking, ask the Ministry of Agriculture to recommend a chemical spray. All insect sprays are dangerous. Show the students how to use them safely. Do not get the spray onto your hands. Do not breathe in the spray. Wash your hands well after using spray. Keep the spray container in a safe place where students cannot get it. Spray on a day of no wind but if you must spray when there is a wind, spray down wind. Make sure the spray does not blow on other people.

History
These teaching materials were originally written and illustrated by Mr J. A. Sutherland, Faculty of Education, University of New England, Armidale, Australia and later edited by Dr J. Elfick, School of Education, University of Queensland, Brisbane, Australia.