About Onion: Onion is one of the most extensively produced vegetable species. It has a variety of non-culinary use, including being used as a moth repellent due to its pungent juice, polishing glass and copperware, and spraying onion concentrated water on plants to boost insect resistance. After China, India is first in terms of area and second in terms of production.
For Onion 13-24°C and 16-25°C are the ideal temperatures for the vegetative phase and bulb development, respectively. Good growth necessitates a relative humidity of around 70%. It thrives in areas where annual rainfall averages 650-750 mm and is evenly distributed during the monsoon season. Deep, friable loam and alluvial soils with high drainage, moisture holding capacity, and sufficient organic matter are ideal for onion growth. The ideal pH range for onions is 6.0-7.5, regardless of soil type, however they can also be cultivated in somewhat alkaline soils.
Varieties: Agrifound dark red, Agrifound white, N-53, Pusa red, Pusa white round, Pusa white flat, Arka kalyan, and Arka lalima are onion varieties.
Procedure and chemicals required: Apply 5 qt. decomposed farmyard manure in 0.05 hectare at the time of the last ploughing and well mix with the soil to raise the nursery. Raised beds with a height of 10-15 cm, a width of 1.0-1.2 m, and a length of 1.0-1.2 m can be made to suit your needs. To manage weeds in the nursery, use the pre-emergence herbicide pendimethalin at a rate of 0.2 percent. To produce seedlings for one hectare, approximately 5-7 kg seeds treated with thiram at 2 g/kg are required. One month before transplanting, apply 20-30 tone FYM/ha and mix it into the soil. Nutrient doses of 100 kg N, 50 kg P, and 80 kg K per hectare are recommended. Before transplanting, the entire amount of phosphate, potassium, and half of the nitrogen should be blended into the soil.
The remaining half of the nitrogen should be used as a top dressing in equal amounts at 30 and 45 days after transplanting. The most conducive to high yields is close planting, with 15 cm between rows and 7.5 cm between plants.For optimal onion production, apply 15 kilogramme sulphur/ha to soils with a sulphur level above 25 kg/ha, and 30 kg sulphur/ha to soils with a sulphur level below 25 kg/ha.
Pest control: Thrips can reduce yields by up to 50% if they are not effectively handled. If an infestation is discovered in the field, apply Fipronil (Regenta) at 30 mL/15 lt water or Prophenophos at 10 mL/10 lt water every 8-10 days. The infestation of maggots was discovered in the months of January and February. Spraying Chlorpyriphos at a rate of 2 litres per acre with irrigation water or sand is used to manage it. Purple blotch and stemphylium blight infestations can result in yield losses of up to 70%. It is sufficient to spray Propineb 70 percent WP@350 gm/acre/150 lt of water twice at a 10-day interval.
After 72-73 days of harvesting, the onion’s germination can be tested by storing it at 300 degrees for 9 days. With this method, we can store onions at room temperature for three months.