Advisory for the month of August 2023
A. For transplanting kharif onion seedlings
1. Chemical fertilizers @ 110:40:60 kg N, P2O5, K2O per hectare need to be applied. Also apply 15 kg sulphur/ha in soils having available sulphur level above 25 kg/ha while 30 kg sulphur/ha for soils having sulphur content below 25 kg/ha. Nitrogen @ 40 kg and full dose of P2O5 and K2O and sulphur needs to be applied at the time of planting. Remaining dose of N needs to be applied in two equal splits at 30 days and 45 days after transplanting.
2. If onion is grown with drip system, application of 40 kg nitrogen as basal dose at the time transplanting and remaining nitrogen in six equal splits through drip irrigation should be applied up to 60 days from transplanting at 10 days interval.
3. Biofertilizers @ 5 kg/ha each Azospirillum and phosphorus solublizing bacteria are recommended along with inorganic fertilizers as basal dose.
4. Apply oxyflurofen @ 23.5% EC (1.5 -2.0 ml/L)/ pendimethalin @ 30% EC (3.5-4ml/L) before transplanting or at the time of transplanting.
5. Seedlings of 35-40 days old should be transplanted at a spacing of 15 ×10 cm (15 cm between the rows and 10 cm between plants).
6. Proper care should be taken while selecting seedlings for transplanting. Over and under aged seedlings should be avoided. Top ⅓rd of seedlings should be cut before transplanting.
7. The onion seedling should be transplanted after dipping roots in carbendazim solution (0.10 %) to reduce the incidence of fungal diseases.
8. Irrigation at the time of transplanting and three days after transplanting is advised for good establishment.
B. For standing kharif onion crop
1. If there is a continuous rainfall, the excess water should be drained out properly to avoid anthracnose incidence.
2. First top dressing of nitrogen @ 25 kg/ha may be applied at 30 days after transplanting.
3. If nitrogen deficiency (yellowing of leaves) appears in the field due to nitrogen leaching, foliar application of urea @ 10 g/l is recommended to overcome nitrogen deficiency.
4. If there is a continuous rainfall for three days, relative humidity (more than 85%) and cloudy condition, the farmers are advised to give first prophylactic spray with benomyl @ 0.2% to control anthracnose disease.
5. Second prophylactic spray with *methomyl (0.8 g/l) along with mancozeb (2.5 g/l) after 15 days of benomyl spray is recommended. This will take care of foliar diseases and thrips incidence.
C. For raising late kharif onionnursery
Following points need to be considered while preparing late kharif nursery.
1. About 0.05 hectare nursery bed area and 5-7 kg of seeds is recommended for getting seedlings to transplant in one hectare.
2. Deep ploughing is recommended for exposing the insect pupae and weed seeds to sunlight.
3. The debris of previous crops, weeds and stones should be removed before bed preparation.
4. Apply half ton of well decomposed farmyard manure in 0.05 ha.
5. Raised bed of 10-15 cm height, 1 m width and length as per convenience need to be prepared.
6. Application of pre-emergence herbicide pendimethalin @ 0.2 % is recommended to control weeds in nursery.
7. Seeds should be treated with carbendazim @ 1-2 g/kg seed before sowing to avoid soil born diseases.
8. Application of Trichodermaviride @ 1250 g/ha is also recommended to manage damping off and raise healthy seedlings.
9. Apply 4:1:1 kg NPK/500 sq. m before seed sowing.
10. Seeds should be sown in lines at 50 mm to 75 mm apart. After sowing, the seeds should be covered with fine powdered farmyard manure or compost followed by light watering. Drip or sprinkler irrigation is recommended.
11. Hand weeding needs to be done 20 days after sowing.
12. Apply 2 kg N /500 sq.m after hand weeding.
13. Foliar spray of benomyl @ 0.2 % is recommended to control soil borne diseases.
14. When the severity of thrips infestation is high, foliar application of fipronil/profenophos @ 1 ml/litre is recommended.
15. Foliar application of mancozeb/tricyclozole/hexaconazole @ (0.1%) is recommended.
D. For stored rabi onion and garlic bulbs
1. Monitor stored bulbs regularly for sprouting and rottage. Rotted and bruised bulbs if any should be removed immediately. Make sure that ventilation is proper.
2. Onion bulbs should be spread properly with heap height up to 4-5 feet only.
3. Garlic bulbs with leaves should be stored in ventilated storage structure by hanging or in circular heaps tapering towards top.
Note: Carbosulfan, profenophos, fipronil, spinosad and methomyl are recommended only when the thrips damage is visible. Mancozeb, hexaconazole, propiconazole and tricyclozol are recommended only when the disease incidence is visible.