Causes and countermeasures for the emergence of cotton in the coastal areas of Jiangsu and its countermeasures

Huo Jinquan, Chen Genxiang, Yang Changming, Sun Jialiang (2nd Seed Company, Yancheng City, Jiangsu Province)

Jiangsu's coastal cotton area is adjacent to the Yellow Sea to the east and the Lixia River to the west. It is a key cotton area in Jiangsu Province. The annual cotton planting area is about 200,000 hm2, accounting for about 55% of the province's cotton area, of which more than 95% are transplanted and transplanted. Over 90% of the varieties are hybrid insect-resistant cotton. In the spring sowing of cotton, no matter how good the seed quality is, there will be irregularities in some cotton fields each year. This not only affects the normal production of cotton, but also has complicated factors and disputes. If the interpretation is not effective, the situation will be affected. Difficult to suppress, it is very unfavorable to build a harmonious society. For this reason, through years of investigation and research, we have conducted a detailed analysis of the reasons for the uneven emergence of cotton in the region, and put forward corresponding measures and countermeasures.

1 Reason analysis

1.1 Influence of water

1.1.1 Insufficient bottom water

The soil of this cotton area is sandy loam soil, but it has good permeability but poor water retention capacity. Some cotton fields affect seedling emergence due to insufficient watering at the bottom of sowing, which is the main reason for the emergence of uneven crops in the coastal cotton area and accounts for the entire problem above 50. The main manifestations are: seedling emergence around the seedbed is better and the middle emergence is poor; seedlings with low seedling emergence is better, and high seedling emergence is poor. Unravelling the cotton seed that did not emerge, the vast majority still have vitality.

1.1.2 Poor water quality

There are few river nets in the coastal cotton areas, and some cotton farmers use the small water in the bottom ditch or the salt water in the small ponds for sowing, because their salt content is relatively high and they cannot grow. The maximum amount of salt that can be tolerated by cotton is 0.3%, while salt content in salty water measured in minor ditches or small ponds is as high as 0.5%. The seedbed shows that the cotton seeds can germinate but it is difficult to establish seedlings.

1.2 Effect of basal fertilizer

Before sowing, some farmers used ammonium bicarbonate, urea, or unfermented human and animal manure in the bed soil. After inoculating the cover film, the bed temperature increased and ammonia gas and other toxic gases were released, causing the seeds to suffocate. Field diagnostics seedbed edge temperature low ventilation good part of the emergence of seedlings, high temperature in the middle of the emergence of few places. After checking the soil, the seeds have lost their viability.

1.3 Influence of temperature

1.3.1 After sowing, it was even wet

Some farmers do not pay attention to the weather when planting. After sowing, they encounter continuous rain, less sunshine, and lower temperatures. During the germination, the cotton seeds do not reach the optimum temperature. This results in poor seed germination and loss of viability.

1.3.2 Immersion cold injury

Some cotton farmers covered the seedbed with a 3-wire thick plastic film. After sowing, they also attacked with cold waves. This allowed the cotton seeds to absorb water at low temperatures around l0°C for a short period of time, and the embryos were damaged and unable to germinate normally. The specific performance is: The closer the time comes from the low temperature, the poorer the seedling emergence; the better insulation condition is better than the poor insulation condition. Dissected seeds that have not emerged have been found to have lost their ability to germinate. In 2006, Dafeng City, a farmer 2.4hm2 cotton fields, the germination rate of the cotton seeds purchased by the indoor test as high as 95%, after encountering low temperatures the day after sowing, the field seedling rate is only 20% to 50%.