How to ripen cotton correctly with ethephon

Years of practice shows that the correct use of ethephon to accelerate ripening in late-maturing cotton fields is a simple and easy measure to increase production and income. Late-maturing cotton sprayed with ethephon can open bolls 7-10 days earlier, increase the pre-frost flowering rate by 10% Mur20%, increase the yield by 6.4% Murray 10.2%, and increase income by 50-100 yuan per mu. Moreover, the ripening cotton field is also beneficial to the sowing and yield improvement of wheat and other crops. However, ethephon is a double-edged sword, if not used properly, not only can not increase production and income, but will lead to a reduction in production and income. Therefore, the use technology of ethephon must be accurately mastered and used scientifically in order to achieve the desired results.

In order to select the suitable cotton field, we should choose the cotton field with greedy green late maturity and strong late maturity, mainly interplanting cotton field, summer sowing cotton, and strong post-occurrence hybrid spring cotton. If there are more than 80% of the cotton fields with boll period of 40-45 days, the effect of pesticide application will be particularly good. Ethephon should not be applied to cotton fields with normal development and maturity, especially those with a tendency of premature senescence, otherwise it will lead to premature withering of cotton plants and reduction of yield and yield. Ethephon can not be sprayed on the cotton in the improved seed breeding field. If it is sprayed, the utilization value of the seed will be greatly reduced.

Correctly grasp the appropriate period of pesticide application

The effect of spraying ethephon is closely related to the temperature. Ethephon can decompose and release ethylene only when the temperature is above 20 ℃. Therefore, after spraying in cotton fields, it is required that the daily maximum temperature above 20 ℃ can be about 15 days in order to get a good effect. According to this principle, the spraying time in the cotton area of northern China mainly refers to the frost falling period, which should be 20 days before the dry frost period. In general years and under general circumstances, it is appropriate to spray around the first ten days of October in North China.

Spraying method and dosage

If the pesticide is applied in early October, 40% ethephon 100 ml per mu, 50 kg of water, diluted evenly and then sprayed; if the pesticide is applied from the end of early October to the beginning of October, 150 ml per mu and 60 kg of water are needed, diluted and sprayed evenly. The diluted solution was aimed at the green bolls of cotton plants with bolling period of more than 40 days, and sprayed evenly from top to bottom, so that every cotton boll that needed to be ripened was filled with liquid medicine.

Spray ethephon and 2% superphosphate mixture

Spraying 2% superphosphate diluent in the later stage of cotton can promote precocious maturity, prevent premature aging, increase yield and income, and generally increase production by about 5%. Because calcium superphosphate is an acidic chemical fertilizer, when mixed with acidic ethephon, it not only does not affect the efficacy of ethephon, but also has a synergistic effect, which is worth popularizing according to local conditions. Methods: first, 1 kg of high-quality calcium superphosphate was digested with 50-60 kg of clear water, the residue was filtered, and then ethephon per mu was added, mixed evenly and sprayed.

Several problems needing attention in the use of ethephon

Ethephon is an acidic pesticide, which is easy to decompose and fail when it comes to alkaline substances, so it must not be mixed with alkaline pesticides. Ethephon diluent prepared should not be stored, but should be used as soon as it is prepared. Second, after spraying ethephon in the cotton field, if it rains within 6 hours, it needs to be sprayed again after the rain. Third, before application, the bolls of cotton bolls should be harvested so as to avoid the decline of cotton quality caused by spraying.