Seed rate calculation1
- 2. How do I calculate seed per hectare?
- 3. • Quantity of seed sown per unit area. • The seed rate depends on spacing or plant population, test weight, germination percentage. • Seed rate (kg/ha)= 𝑷𝑷𝑷𝑷𝑷𝑷𝑷𝑷𝑷𝑷 𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑× 𝑻𝑻𝑻𝑻𝑻𝑻𝑻𝑻 𝒘𝒘𝒘𝒘𝒘𝒘𝒘𝒘𝒘𝒘𝒘𝒘× 𝟏𝟏𝟏𝟏𝟏𝟏 × 𝟏𝟏𝟏𝟏𝟏𝟏 𝒈𝒈𝒈𝒈𝒈𝒈 𝒈𝒈𝒈𝒈𝒈𝒈𝒈𝒈𝒈𝒈𝒈𝒈𝒈𝒈𝒈𝒈𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑 × 𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑 𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑𝒑 × 𝟏𝟏𝟏𝟏𝟏𝟏𝟏𝟏 × 𝟏𝟏𝟏𝟏𝟏𝟏𝟏𝟏 • Plantpopulation= 𝒍𝒍𝒍𝒍𝒍𝒍𝒍𝒍 𝒂𝒂𝒂𝒂𝒂𝒂𝒂𝒂 𝒔𝒔𝒔𝒔𝒔𝒔𝒔𝒔𝒔𝒔𝒔𝒔𝒔𝒔
- 4. 1. Calculate the seed rate of mung bean for sowing 1 hectare of crop from the following: spacing=30cm×10cm germination %=92% purity %=85% 1000 grain weight =36g Solution: Plant population= 10000𝑚𝑚𝑚 0.3𝑚𝑚×0.1𝑚𝑚 =333333.33 Seed rate = 333333.33×36×100×100 92×85×1000×1000 =15.34 kg/ha (Ans).
- 5. 2. Calculate the seed rate of pigeon pea for sowing 1 hectare of crop from the following: spacing=60cm×25cm germination %=87% purity %=86% 1000 grain weight =70g Solution: Plant population= 10000𝑚𝑚𝑚 0.6𝑚𝑚×0.25𝑚𝑚 =66666.67 Seed rate = 66666.67×70×100×100 87×86×1000×1000 =6.23 kg/ha (Ans).
- 6. 3. Calculate the seed rate of ground nut for sowing 1 hectare of crop from the following: spacing=50cm×20cm germination %=92% purity %=95% 1000 grain weight =200g shelling%=60% Solution: Plant population= 10000𝑚𝑚𝑚 0.5𝑚𝑚×0.2𝑚𝑚 =100000 Seed rate of kernels= 100000×200×100×100 92×95×1000×1000 =22.88≈23 kg/ha Quantity of unshelled pods needed for sowing in kg/ha = 100/60×23=38.33 kg/ha (Ans).
- 7. 4. Calculate the seed rate of green gram for sowing 1 hectare of crop from the following: spacing=45cm×10cm germination %=80% 1000 grain weight =48g Solution: Plant population= 10000𝑚𝑚𝑚 0.45𝑚𝑚×0.1𝑚𝑚 =222222.22 Seed rate= 222222.22×48×100 80×1000×1000 =13.33 kg (Ans).
- 8. 5. Calculate the seed rate of Jute for sowing 1 hectare of crop from the following: spacing=25cm×10cm germination %=90% purity percentage= 85% test weight =6.5g Solution: Plant population= 10000𝑚𝑚𝑚 0.25𝑚𝑚×0.1𝑚𝑚 =400000 Seed rate= 400000×6.5×100×100 90×85×1000×1000 =3.39 kg (Ans).
- 9. 6. Calculate the quantity of maize seed for sowing 1 hectare of crop from the following: spacing=75cm×20cm germination %=90% purity percentage= 90% test weight =250g seed required for gap filling=5% of total weight of seeds. Solution: Plant population= 10000𝑚𝑚𝑚 0.75𝑚𝑚×0.2𝑚𝑚 =66666.67 Seed rate= 66666.67×250×100×100 90×90×1000×1000 =20.576 kg Amount of seed required for Gap filling= 5 100 ×20.576= 1.028 kg Total seed required for 1 hectare area= 20.576+1.028=21.604≈ 22kg/ha (Ans).
- 10. 7. Calculate the seed requirement for upland rice for sowing 1 hectare of crop from the following: spacing=20cm×30cm germination %=95% purity percentage= 90% test weight =25g No. of damaged seeds by birds, which are to be replaced 10seeds per square meter i.e., 10/m². Solution: Plant population= 10000𝑚𝑚𝑚 0.2𝑚𝑚×0.3𝑚𝑚 =166666.67 Replacing bird damaged seeds, 1m² area= 10 seeds 10000m² area= 100000seeds Total no. of plant population= 166666.67 +100000=266666.67 Seed rate= 266666.67×25×100×100 95×90×1000×1000 = 7.79≈8 kg/ha (Ans).
- 11. 8. Calculate the seed requirement for rice in kg/ha for sowing 1 hectare of crop from the following: spacing of hill=20cm×20cm No. of seedlings per hill=3 germination %=95% purity percentage= 90% test weight =25g seedlings required for gap filling=12/5 m² area Solution: Plant population= 10000𝑚𝑚𝑚 0.2𝑚𝑚×0.2𝑚𝑚 =250000×3= 750000 Seedlings required for gap filling. For 5m² seedlings required= 12 For 10000m²= 12/5×10000=24000 seedlings. Total plant population= 750000+24000=774000 Seed rate= 774000×25×100×100 95×90×1000×1000 =22.63 kg/ha (Ans).