Advisory for the month of September 2020

Transplanting of kharif onion crops is over and the crops are almost 15-45 days old. Nursery has to be raised for late kharif onion in this month. Some farmers have already raised late kharif onion nursery and their onion seedlings are ready to transplant. The following advisory should be followed in these conditions.  

A.  For standing kharif onion crop 

1.      If there is a continuous rainfall, the excess water should be drained out properly to avoid anthracnose incidence. If there is drought, the advisory as given on this website under ‘Agropedia’ may be followed.

2.      First top dressing of nitrogen @ 25 kg/ha may be applied at 30 days after transplanting.

3.      One hand weeding is recommended at 40-60 days after transplanting.

4.      Second top dressing of nitrogen @ 25 kg/ha may be applied at 45 days after transplanting.

5.      Foliar application of micronutrient mixture at 5 g/L is recommended at 45, 60 and 75 days after transplanting.

6.      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.

7.      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.

8.      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.

9.   If thrips and foliar diseases are not fully controlled by above sprays, another spray of profonophos (1 ml/L) + hexaconazole @ (1g/L) can be made followed by a spray of fipronil (1 ml/L) along with propiconazole @ (1.0 g/L) after 15 days of previous spray, if required.

 

B. For raising late kharif onion nursery

It is time to raise the nursery of late kharif onion. The 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 Trichoderma viride @ 1250 g/ha is also recommended to manage damping off and raise healthy seedlings.

9.      Apply 4:1:1 kg NPK/500 m² 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 m² 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/L is recommended.

15.   Foliar application of mancozeb/tricyclozole/hexaconazole @ 0.1% is recommended.

 

C. Main field preparation for late kharif onion

Main field should be prepared and kept ready for late kharif seedlings transplanting.

1.      Field should be ploughed and disked properly to eliminate debris and soil clods.

2.      Apply FYM 15 t/ha or poultry manure 7.5t/ha or vermicompost 7.5 t/ha at the time of last ploughing and level the field properly prior to bed preparation.

3.      Adopt broad bed furrows (BBF) of 15 cm height and 120 cm top width with 45 cm furrow. BBF method is suitable for drip and sprinkler irrigation.

4.      For drip irrigation, each BBF should have two drip laterals of 16 mm size. Distance between two inbuilt emitters should be around 30-50 cm and discharge flow rate of 4L/h is advised.

5.      For sprinkler the distance between laterals (20 mm) of micro sprinkler should be 6 m with a discharge rate of 135L/h.

D.   For transplanting late kharif onion seedlings

Transplanting should be done after fertilizers and weedicides application as given below.     

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 70 kg nitrogen as basal dose at the time transplanting and remaining nitrogen in seven 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 rd 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.

E.    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.