Agronomic Practices for Soybean Production Required in Support of Proper Monitoring & Evaluation (M&E)

By Niyi Adegbaju

Our last topic was centered on sesame production. Today, we shall talk about agronomic practices for soybean (Glycine max) production in Nigeria required in support of proper monitoring & evaluation (M&E). 

     

Land Preparation

Plough, harrow and ridge manually with a hoe or animal drawn implement or tractor. It can also be planted on flat seedbeds.

2.      Site Selection: Well drained deep soil of pH 4.5 to 8.5

3.      Seed Selection: Select seed based on maturity, yield potential, lodging, drought tolerance, and resistance to pests and diseases.

Table 1: Recommended varieties for Guinea savanna ecological zones in Nigeria.

Variety	Ecology	Characteristics	Striga control
TGX 1448-2E	Southern and  northern Guinea savannas	Medium maturing, high yield, low shattering, high oil content, excellent grain color	Good
TGX 1835-10E	Guinea savanna	Early maturing, rust resistant, pustule resistant	Not known
TGX 1485-1D	Guinea savanna	Early maturing, pustule resistant, rust susceptible	Not known

4Planting Dates: Depends on the ecological zone. Early June – Early July at Southern Guinea Savanna; Mid June – Early July at Northern Guinea savanna–Sudan savanna

5Seed Requirement: About 50–70 kg (20–28 standard mudus) are required to obtain a

population of 444,444 plants/ha. Use seeds that are not more than 12 months old to ensure proper germination rate.

 Seed Dressing

Treat seeds with fungicides, such as Captan, Apron Plus, or Thiram, at the rate of 1 sachet/8 kg of seeds before planting.

7Plant Spacing and Sowing

Sow soybean by hand, planter, or by drilling. Plant 3 to 4 seeds/hole at a spacing of 75 cm by 10 cm between stands. Alternatively, drill seeds at 50–75 cm between rows and 5 cm within rows.

8Fertilizer Requirement

Fertilizer recommendation is based on soil test. Apply phosphorus at the rate of 30 kg p/ha in the form of single super phosphate fertilizer (SUPA) (3 × 50 kg bags) in addition to 2½ × 50 kg bags of compound fertilizer NPK 15:15:15.

9Weed Management

        i.            Manual weed control: first weeding at 2 WAP and the second at 5–6 WAP

      ii.            Chemical weed control: If herbicide is applied at planting, one weeding may be required at 5–6 weeks after planting. Always consult product labels and follow directions regarding application rates, timing. The following herbicides are recommended based on type of weed prevalence:

Table 2:Recommended herbicides for soybean production

Product	Product rate/ha (L)	Time of application	Remarks
Paraquat + Pendimethalin (50EC)	3 L of Paraquat plus 3 L of Pendimethalin (250mL of each/20-L sprayer)	Applied within 2 days of planting	Where grasses, e.g., Rottboellia are common
Paraquat + Dual Gold	3 L of Paraquat plus 2 L of Dual Gold(= 250 mL of Paraquat plus 200mL of Dual Gold in 15-L sprayer (= 1½milk tins of Paraquat plus 3/4milk tins of Dual Gold	Applied within 2 days of planting	Controls most grasses and broadleaf weeds. Where sowing is done after 1 week of land preparation, application must be within 12 h after planting.
Round-up or other Glyphosate products	4 L (= 350 mL/15-L sprayer)	Pre-emergence (before land preparation)	Used under no-tillage system, applied at least 2 weeks before sowing also to control perennial weeds
Fusilade forte	1–1½ L (150 mL (= 1 milk tin)/15-L sprayer	Post-emergence Apply 21–28 days after sowing	For grass weed control

1Water requirement & Irrigation

Soybeans may require 1 to 2 inches of water every 3 to 7 days during the peak use periods. This depends on the type of soil. Coarse-textured soils (sands) have a much lower water-holding capacity than the finer-textured soils, so soybeans on sandy soils require much more frequent irrigation.

1Insects and Control

Bean Leaf beetles, Stem borers, Grasshoppers, Leafhoppers. It is more susceptible to whitefly attack at vegetative stage. From flowering onwards it becomes more attractive to, pod-sucking bugs that can seriously reduce seed quality - single spray of Cypermethrin + Dimethoate 10 EC at the rate of 100 mL in 15 L of water.

1Diseases and control

Root and stem rot, Brown spot, pod and stem blight, Frogeye leaf spot

To control these diseases: i. Plant resistant varieties. This is the best option to control disease. ii. Plant in a good seedbed. iii. Plant seeds treated with fungicides as mentioned earlier under ‘seed dressing’.

Rotate crops with maize, sorghum or wheat to prevent the increase in inoculums level in a field.

1Harvesting

Harvest by cutting the mature plant at ground level when about 85% of the pods have turned brown for a non-shattering variety but 80% for shattering varieties.

1Storage

Store at a moisture content of 10% or less. Dry to 13% moisture for storage of 6–12 months and to

10–11% for longer storage. (A soybean seed is sufficiently dry when it cannot be dented with the teeth or fingernails.)

Please find the summary in the table below:
Key: -MBP= Month before planting, MAP=Month after planting, WBP= Week before planting, WAP=Week after planting, DOP=Days of planting, HAP=Hours after planting, DAS=Days after sowing, W0= @ Planting 

Activity/Operation	Timeline	Description of Activity
Land selection	3-2MBP	Select a land that has well-drained sandy-loamy soil for soybean farming. An ideal soil pH of 4.5 to 8.5
Seed selection and input procurement	2-1MBP	Select quality seed variety. This is based on maturity, yield potential, lodging, drought tolerance, and resistance to pests and diseases. Seeds and other inputs (fertilizer and herbicide) should be procured from reputable agro-dealers. Some recommended soybean varieties are TGX 1448-2E, TGX 1835-10E, TGX 1485-1D.
Land preparation	2WBP	Clearing and stumping: Clear the land using mechanically or manually (hoe) without burning. Tillage: Till the soil by ploughing and harrowing. Thee helps to break, mix, soften, and make the soil medium fine and smooth.
Planting	W0	Planting date: Depending on the ecological zone, plant soybean early June – early July at Southern Guinea Savanna; mid-June – early July at Northern Guinea savanna–Sudan savanna Seed rate and spacing distance Sow seeds at spacing of 50 - 75cm between rows and 5-10cm within stand at 2 -3 seeds per stand to ensure proper germination rate. Sow seeds that are not more than 12 months old. About 50–70 kg (20–28 standard mudus) are required to obtain a population of 444,444 plants/ha. Seed dressing: Treat seeds with fungicides, such as Captan, Apron Plus, or Thiram, at the rate of 1 sachet/8 kg of seeds before planting.
Weed management	2WAP & 5-6WAP	Manual weed control at 2WAP and 5-6WAP Note: One Chemical weeding may be required at 5-6WAP if herbicide is applied at planting. The following herbicides are recommended based on type of weed prevalence: Paraquat + Pendimethalin(50EC) 3 L of Paraquat + 3 L of Pendimethalin (250mL of each/20-Lsprayer) for grasses eg Rottboellia – apply within 2DOP; Paraquat + Dual Gold 3 L of Paraquat + 2 L of Dual Gold(= 250 mL of Paraquat + 200mL of Dual Gold in 15-L sprayer (= 1½milk tins of Paraquat plus 3/4milk tins of Dual Gold - for most grasses and broadleaf weeds within 12HAP; Fusilade forte(Post emergence) 1–1½ L (150 mL(= 1 milk tin)/15-L sprayer - for grass weeds – apply 21-28DAS
Fertilizer management	3WAP	Depends on soil fertility test. Phosphorus is often the most deficient nutrient and should be incorporated during land preparation, Nitrogen and potassium fertilizers are needed only when there are obvious deficiencies. But the usual recommendations are: 20 kg/ha N; 20 kg/ha K2O; and 40 kg/ha P2O5 Materials needed: 2½ × 50 kg bags of NPK (15-15-15) plus 3 × 50 kg bags of SSP (SUPA)
Water management		Soybeans may require 1 to 2 inches of water every 3 to 7 days during the peak use periods. This depends on the type of soil. Coarse-textured soils (sands) have a much lower water-holding capacity than the finer-textured soils; soybeans on sandy soils require much more frequent irrigation.
Pest management		Bean Leaf beetles, Stem borers, Grasshoppers, Leafhoppers. It is more susceptible to whitefly attack at vegetative stage. From flowering onwards it becomes more attractive to, pod-sucking bugs that can seriously reduce seed quality- single spray of Cypermethrin + Dimethoate 10 EC at the rate of 100 mL in 15 L of water.
Disease management		Root and stem rot, Brown spot, pod and stem blight, Frogeye leafspot, Yellow mosaic disease caused by whitefly Control:  i. Plant resistant varieties. ii. Plant in a good seedbed. iii. Plant seeds treated with fungicides as mentioned earlier at seed dressing iv. Rotate crops with maize, sorghum or wheat to prevent the increase in inoculums level in a field.
Harvesting	3-4MAP	Soybean matures within 3–4 months after planting. Cut the mature plant at ground level when about 85% of the pods have turned brown for a non-shattering variety but 80% for shattering varieties. Stack them loosely on tarpaulin and allow them to dry in the open for 2 weeks before threshing.
Post-harvest & storage		Store at a moisture content of 10% or less. Dry to 13% moisture for storage of 6–12 months and to10–11% for longer storage. (A soybean seed is sufficiently dry when it cannot be dented with the teeth or fingernails.)