Legume and Oil Seed Growing

Legume and Oil Seed Growing Introduction

What legume or oil seeds do you grow or know? Legumes are plants with dicotyledonous seeds aligned in fruits called pods. Legumes or pulses include peas, beans, soybeans and lentils. Common Legumes are grown for their seed. However, forage legumes, such as alfalfa, lablab, desmodium, centro and clovers are also grown for feeding farm animals. On the other hand, oil seed plants refer to any of the plants that are grown purposely for their oil. Commonly grown oil seeds in Uganda include sun flower, simsim and groundnuts.

Legumes and oil seeds do well in a variety of climatic and soil conditions and have a long shelf-life if well dried before storage. As long as there are efficient storage facilities such as hermatic bags, silos and tanks, Longevity of storage is possible with legumes and oil seeds. Therefore, in this chapter, you will learn how to grow and store legume and oil seeds for market.

Identifying Legumes and Oil Seeds

What legume or oil seeds have you ever eaten or seen? Legumes, also called pulses, are grown for their proteinous seed enclosed in pods. A pod is the fruit of a legume. Also, oil seeds, such as, sesame or simsim and groundnuts develop in pods. Using Figure 2B.1 and Activity 2B.1, identify legume and oil seeds.

Structure of a Seed

A seed is a mature fertilised ovule. Legumes and oil seeds are characteristically dicotyledonous. A seed has two cotyledons or seed leaves enclosed in a testa with a plumule sandwiched in the cotyledons. Have you ever opened any legume or oil seed? What did you find in the seed? The external parts of a seed include the testa or seedcoat, hilum or stalk scar and micropyle. The opening of a seed will show an embryo and cotyledons. Using Figure 2B.2 and Activity 2B.2, you are going to examine the structure of a seed and identify its constituent parts.

Functions of the Parts of Legume and Oil Seeds

A seed is alive when the different parts play different roles. For example, the testo protects the inner parts of the seed from mechanical injury and chemical and bacterial invasion that would otherwise damage the embryo. The embryo develops into a new plant. Other parts of a seed, such as, cotyledon, micropyle and tegmen play different roles. In Activity 28.3, identify and explore the functions of the parts of legume and oil seeds.

Activity 28.3 Discovering the functions of the parts of a seed

What you need:

legume or oil seeds, razor blade, notebook, pen

What to do:

1. In groups, using a razor blade, open the legume and oil seeds provided.

2. Examine the structure and composition of each part with a view of understanding the function that the part plays.

3. Identify the structural features that you have discovered for each part.

4. Discuss how the structure of the part helps you to understand its function.

5. Discuss the functions of each of the parts of the seed.

6. Exchange your notebooks with other groups to find out what they have researched on the functions of the parts of the legume or oil seed.

7. As a class, use a newsprint to record the functions of all the parts of a legume or oil seed.

8. Display the newsprint beside the structure of the seed.

Seed Dormancy

Have you ever seen a garden where seeds failed to germinate? Did you know that seed dormancy could be the most likely cause? Seed dormancy is a condition of failure of seeds to germinate despite availability of favourable conditions. The conditions necessary for seed germination include oxygen, water or moisture, suitable temperature and light. A dormant seed fails to germinate even when conditions are favourable. A seed that germinates when such conditions are provided is a viable seed. In Activity 2B.4, you will examine the types of seed dormancy.

Activity 2B.4 Examining the types of seed dormancy

What you need:

Overstayed legume or oil seeds, Abscisic Acid (ABA), newly harvested dry seeds, pre-maturely harvested seeds, notebook, pen

What to do:

1. In groups, soak some newly harvested dry seeds in Abscisic Acid for 30 minutes.

2. Remove seeds from the acid and keep them dry for 24 hours.

3. Plant a known number of overstayed, pre-maturely harvested, newly harvested dry seeds and ABA treated seeds in rows and known spacing on separate petri dishes.

4. Make sure the petridishes receive all the conditions necessary for germination.

5. Observe seed germination on each petridish after five days.

6. Calculate the percentage dormancy on each petridish as;

7. Research and record the meanings and causes of physical, physiological and chemical types of dormancy.

8. Classify the causes of dormancy on different plots into three types as physical, physiological or chemical dormancy.

9. Identify other factors that make seeds dormant.

10. Compare the calculated seed dormancy with the acceptable seed dormancy of 15%. Are the seeds worth planting? Give reasons to support your answer.

11. Use the following table to identify the types of seed dormancy and their causes.

Methods of Breaking Seed Dormancy

In all crop production enterprises, seed dormancy is undesirable in all plants that undergo seed propagation. Planting dormant seeds can cause serious losses in economy, labour and time. Use Activity 2B.5 to explore and practice the methods of breaking seed dormancy.

Activity 2B.5 a) Matching items about seed dormancy

What you need:

Notebook, pen

What to do:

In pairs, correctly match the method of breaking seed dormancy in list A with its meaning in list B.

2. Name other methods of breaking seed dormancy you know. Which of the methods is used in your community?

3. State how each of the methods help you in breaking seed dormancy.

4. Using the library or the Internet, get information on the steps of breaking seed dormancy in each of the methods.

5. Present a report to the teacher describing the findings of your research.

Activity 28.5 b) Breaking dormancy in seeds

What you need:

dormant seeds, sand paper, needle, ice cubes, water, heat source, synthetic growth hormones, sulphuric acid, notebook, pen

What to do:

1. In groups, use the remaining samples of the seeds that were not planted during Activity 28.4.

2. Group the seeds according to the type of seed dormancy. Research and record the steps of breaking dormancy in each of the methods in Activity 28.5a.

3. Using the materials provided, follow the steps to break dormancy in the seeds.

4. Plant the seeds to establish the effectiveness of the method you used.

5. Calculate the percentage dormancy using the formula:

6. Find out whether the method you used reduced the percentage dormancy.

7. Discuss how you can increase the effectiveness of the method of breaking dormancy that you used.

8. Share experiences with peers and write a report to the teacher for further guidance.

Value of Legumes and Oil Seeds in Nutrition

Legumes are valued worldwide as a sustainable and inexpensive alternative to meat and are considered the second most important food source after cereals. The nutritional superiority of legumes and oil seeds has been ascribed economical, cultural, physiological and medicinal roles owing to their possession of beneficial bio-active compounds.

Oil seed crops are grown primarily for the oil contained in their seeds. They have been cultivated throughout much of the world for at least four thousand years. In earlier times, oil seeds were primarily used as lamp oil, but later on, they were used to make soaps. Using Figure 2B.3 and Activity 2B.6, examine the value of legume and oil seeds in nutrition.

Activity 2B.6 Examining the importance of legumes and oil seeds in nutrition

What you need:

Variety of legume and oil seeds, nutritionist/catering officer/food and Nutrition teacher, razor blade, notebook, pen

What to do:

1. In groups, you will receive legume and oil seeds products. 2. Observe the crop products and record their names.

3. Record the explanation of the nutritionist/catering officer/food and nutrition teacher on the nutritional benefits of legume and oil seeds. 4. Ask the nutritionist to guide you on how to prepare the products for

eating while maintaining the nutrient composition. 5. Follow these steps to carry out a food test to discover the nutrients in legumes and oil seeds.

a) Crush some legume or oil seeds in a mortar using a pestle. b) Add a spatula-full of crushed legume or oil seeds to a boiling tube.

c) Add 5 cm³ of distilled water and stir.

d) Boil and simmer for one minute. table.

e) Cool and add the test reagent. Record your findings in the following

6. Find out the importance of such nutrients in the functioning of the human body.

7. Get guidance on the recommended rates of consumption of legume and oil seeds. Find out the reasons such rates of consumption are recommended.

8. On a newsprint, write a menu for your class to follow when you harvest your legume and oil seeds.

Value of Legume and Oil Seeds as a Commodity

What legume and oil seed or their products have you ever seen in the market, shop or supermarket? Legume and oil seeds are essential contributors to income security in many parts of sub-Saharan Africa. Legume and oil seeds can be seen in markets as fresh or dry seeds especially beans, or processed products such as simsim paste, groundnut paste, roasted groundnuts or even flour. Use Activity 2B.7, examine the importance of legume and oil seeds as a commodity.

Activity 2B.7 Examining the importance of legume and oil seeds as a commodity

What you need:

Notebook, pen, camera

What to do:

1. In groups, visit a market place or trading centre near your school.

2. Identify the legume and oil seed products in the market or shop. Note down the products.

3. Ask the trader to tell you the cost of the product per unit quantity.

4. Inquire about the products obtained from the items seen on sale. 5. Take pictures of the legume and oil seed products on sale identified.

6. Ask the trader about the nature of demand (high or low) of the legume and oil seed crop products identified. Record the findings.

7. Summarise the findings in a table of the following format.

Selection of Legume and Oil Seeds for Planting

When presented with seeds from the store or market, what will you consider in order to choose what seeds you can plant? Not all planting materials are worth planting. Seed dormancy makes seeds unsuitable for planting hence the need for selection. Also, some seeds are mixed up with seeds of undesirable qualities. Selection of seeds for planting can be based on a number of physical characteristics.

When selecting legumes or oil seeds for planting, avoid those that are wrinkled, smaller than the normal size, have high moisture content, rotten have holes and those that have been stored for too long. All seeds selected for planting should have a germinability percentage of not less than 85%. In Activity 2B.9, you are going to test the viability of seeds that will enable you select appropriate seeds for planting.

Activity 28.8 Testing the viability of legume and oil seeds

What you need:

0.1% solution of tetrazolium salt, beaker, gloves, legume and oil seeds

What to do:

1. In pairs, conduct an experiment to test for the viability of a legume or oil seed using tetrazolium salt.

2. Put 20 seeds of good beans or groundnuts in a beaker.

3. Add 0.1% colourless tetrazolium salt solution to completely immerse the seeds.

4. After 30 minutes, remove the seeds from the beaker.

5. Observe the colour change in the solution.

6. Open the seed coat and check the colour of the embryos.

7. Establish the percentage of seeds that are viable by selecting seeds with pinkish or reddish embryos.

8. Examine and write the characteristics of the seeds that could not germinate. 9. Discuss how you can improve the viability of the seeds.

10. Identify other methods of testing seed viability and record the steps in each method.

11. Report your observations, conclusions and recommendations to the teacher for feedback.

Growing of Legume and Oil Seed Crops

Legume and oil seeds are the second largest grown crop worldwide next to cereals. The ability of legume and some oil seeds to improve soil condition gives the seeds a comparative advantage to survive well in a wide range of soil and climatic conditions. The soil condition is improved through biological nitrogen fixation by the help of bacteria that live in their roots.

To realise good yields from legumes, timeliness in crop management practices must be observed. Key routine practices in legume and oil seed growing include tillage, fertiliser application, timely planting (at the onset of rains), proper spacing, weeding, staking (for climbing beans), earthing (for groundnuts) and pest and disease control. How important are the practices in legume and oil seed crop production? Use Figure 2B.4 and Activity 2B.9 to practise growing legume and oil seed crops.

Considerations when Growing Legume and Oil Seeds

Spacing, soil type and maturity rate are important factors to consider in legume and oil seed production. Also, note that different varieties of a given crop have different soil and spacing requirements. For good yields, Table 2B.1 presents information on legume and oil seed growing. Use the table to select a variety of legume or oil seed crop for growing.

Activity 2B.9 Growing legume and oil seed crops

What you need:

Notebook, pen, camera

What to do:

1. In groups, visit a legume and oil seed crop farmer near your school. Alternatively, you can watch videos or observe photographs on legume and oil seed growing.

2. Observe the legume and oil seed crop(s) he or she grows.

3. Ask about the growth requirements of the legume and oil seeds grown .

4. Discuss how the requirements affect the growth and productivity of the crop.

5. Observe the management practices being or were carried out on the legume and oil seed crops during the growing period.

6. Record how the management practices are carried out and give reasons for carrying them out.

7. Ask how and why each of the management practices is conducted in legume and oil seed crop growing.

8. Write a general criterion that you will use to manage your legume and oil seed crop project at school.

9. Establish and manage a legume and oil seed production project at your school. 10. Practise all the routine management practices in a timely manner to realise high yield.

11. Keep records on every field activity conducted and observe for the crop response to the activity.

12. Use the records to improve management of the next phase of legume and oil seed production.

Handling Legume and Oil Seeds During and after Harvest

Harvesting means collecting physiological mature crops from the field. Follow the maturity duration of the crop and conduct regular monitoring for timely harvesting. Proper timing for any crop requires proper records and the purpose to which the crop is to be put. Some legumes are preferred fresh. They should as such be harvested earlier. Some may be required dry. This means the harvest time is dependent on the purpose or market needs. A legume or oil seed crop is mature when the pods have well filled and normal-sized seeds. Use Figure 2B.5 and Activity 2B.10 to practise harvesting of legume and oil seeds.

Activity 2B.10 a) Handling of legume and oil seeds during harvesting

What you need:

Notebook, pen, video clips or photographs on handling of legume and oil seeds during and after harvest.

What to do:

1. In groups, visit a legume and oil seed crop garden where harvesting is being done. Alternatively, watch a video or photographs on harvesting of legume and oil seeds.

2. Identify the techniques used to harvest the legume and oil seeds. Why are the legumes and oil seeds harvested using those methods? 3. Ask the farmer how to identify a legume and oil seed crop ready for harvest. Record the characteristics.

4. Ask the farmer to give you information on how post-harvest handling

practices are carried out. You can also watch the video or photographs

on the following post-harvest handling practices: a) drying (techniques and materials used in drying, and why regular turning is required when drying).

b) moisture content testing. c) how to avoid moisture in cereal crop products. d) threshing techniques and tools or implements used.

e) cleaning threshed legume and oil seeds.

f) storage techniques and structure of the store.

g) proper packaging of legume and oil seed crop harvest.

5. Discuss with the farmer why the post-harvest handling practices are carried out.

6. Record what you learnt about harvesting and post-harvest handling of cereal crop products.

7. Record how you will apply the knowledge and skill in handling your legume and oil seeds during and after harvesting.

8. Write an article for the school magazine indicating the nature of harvest and post-harvest handling of legume and oil seeds in your community.

Activity 2B.10 b) Testing moisture in legumes and oil seeds before storage

What you need:

Physiologically mature legume and oil seed crops, harvesting tools, notebook, pen

What to do:

1. Identify legume and oil seed crops that have reached physiological maturity.

2. Using the required tools, harvest the legume or oil seed crop.

3. Test the moisture content of the harvested seeds using any of the following methods presented in the table. Record findings in the remarks column.

4. Dry the legumes or oil seeds to the recommended moisture content level on a tarpaulin or cemented ground but not a dusty ground.

5. During drying, keep turning to ensure even loss of moisture. 6. Record the harvesting activities.

Storing Legume and Oil Seed

Storage is the process of keeping farm produce until an appropriate time of use. The primary aims of storage are quality maintenance, food and nutrition security, seed and better price. In Africa and Asia, a good portion of the harvested grain Legumes is consumed after having been milled for removal of the husks and splitting, or after some form of processing. However, most of the commercial technologies available for this purpose are either obsolete or inadequate and result in heavy losses due to breakage and powdering of the grain.

Successful efforts have been made to develop improved technologies to reduce milling losses and improve product quality. Similarly, there is need for development and utilisation of improved technologies for legume and oil seed processing. Use Figure 2B.6 and Activity 2B.11, to practice storing and managing legume and oil seeds in stores.

3. Discuss the importance of carrying out each of the management practices.

4. Carry out each of the management practices on your harvested legume and oil seeds.