Cotton: grab the opportunity to make soil moisture early

Although there are still one or two months to go before cotton seedlings and sowing, the current situation of continuous drought in autumn, winter and spring has posed a great threat to cotton planting this year, and according to the situation in previous years, there is little precipitation in our province from March to April. In view of the current situation, Dong Hezhong, deputy director and researcher of the Cotton Research Center of the Shandong Academy of Agricultural Sciences, suggested that cotton farmers should start and prepare early for cotton planting this year, seize the opportunity to create soil moisture according to the weather conditions, actively create soil moisture and protect seedlings against drought, and strive for one sowing of the whole seedling and early development of strong seedlings.

Select improved varieties and prepare for sowing

Science and technology should invigorate agriculture and give priority to improved varieties. In general, phenomena such as non-emergence or poor emergence caused by seed problems can also be remedied by replanting or replenishing seedlings, but this year, due to persistent drought and little rain, poor soil moisture, relative lack of water in various places, and lack of congenital conditions, the quality of seeds is required to be higher. To select seeds, first of all, we must choose the seeds of cotton varieties that have been examined and approved, which require good maturity and high germination rate; secondly, we must buy seeds produced by formal enterprises with complete three certificates, read the instructions and ask for seed invoices; third, 15 days before sowing, choose sunny days to dry seeds for 2-3 days, so as to break seed dormancy and promote germination and emergence.

Excavate water source to make soil moisture and preserve soil moisture

The cotton planting areas in our province are mainly distributed in the north (east), northwest and southwest of Shandong. Most of the seedlings in the southwest of Shandong Province are transplanted, and there is not much water during the seedling raising period, while most of the cotton fields in the north (east) and northwest of Shandong are direct seeding cotton fields, and there are more cotton fields in saline-alkali land, so it is necessary to make soil moisture and sow seeds. Therefore, it is necessary to fully tap water sources and do a good job of creating and preserving soil moisture before sowing.

If there are conditions for watering, seize the opportunity to create soil moisture. Theoretically, it is the best time to make soil moisture 20 days before cotton sowing. In view of the continuous drought and little rain this year, and the shortage of water sources, we should make soil moisture in time according to the situation of local water sources, and rake the soil moisture in time after making it.

If there is no water pouring condition, it is recommended to pre-cover the film to increase soil moisture. About a month before sowing, after soil moisture preparation, plastic film mulching is then carried out, compacting both sides of the plastic film, and digging holes in the film when the temperature is suitable. This method can obviously reduce the water loss of ground evaporation and maintain soil moisture, and has a significant effect on cotton planting in arid and saline-alkali areas, especially after local small-scale precipitation or timely mulching after soil moisture production, the effect is better and is worth popularizing.

Choose sowing methods according to local conditions

Water bag. This is the most effective drought-resistant sowing method when plastic film mulching is not used. The method is as follows: opening a shallow ditch with a depth of about 2.5cm, watering evenly, watering the amount of water to receive the soil moisture at the bottom, and sowing cotton seeds on demand in the underwater infiltration soil; aiming at the cotton row to cover the soil and raising the ridge, 3-5cm higher than the ground; when more than 70% of the seeds take root, flatten at one time.

Resist drought and raise seedlings. On the basis of sufficient moisture and sowing in the seedling bed, properly reduce the water supply of the seedling bed, and gradually carry out the drought tolerance exercise of the seedlings. When the red stem of the seedlings reached half of the successful seedling refining, the drought tolerance adaptability was improved, and it had a certain drought resistance effect after transplanting.

Ditch casting and film coating. Before sowing, open the ditch, water in the ditch, then sow and cover the soil, and then cover with plastic film, this method is suitable for protecting seedlings in dry land.

Flexible determination of sowing date

At present, there are many types of cotton varieties, and the requirements for sowing time are more flexible. Generally, under the condition of plastic film mulching, April 10 to May 10 is the appropriate time for cotton sowing. In previous years, cotton sowing mainly considered the temperature factor, as long as the temperature reached, it began to sow. This year, in addition to considering the temperature factor, we should also pay attention to the soil moisture situation. If the temperature reaches and the soil moisture is insufficient, suggest cotton farmers to wait; on the contrary, if the soil moisture is OK, but the temperature is slightly lower, you can also consider sowing and increasing the sowing amount.