Application Technology of Mepiquat Chloride for the New Large-Boll Cotton Variety Shuofeng No. 9

Characteristics and traits: This variety was developed from the original Shuofeng No. 9 through purification and rejuvenation selection. The plant is tall, with thick and hard stems, a loose plant type, and relatively long fruiting branches with few hairs. The leaves are large and dark green, the bolls are large, long-oval in shape. It emerges well, with uniform seedlings, vigorous growth in the early and mid stages, and growth stabilizing in the late stage, with good uniformity. The first fruiting branch node is low, boll setting is good, boll opening is full and smooth, easy to pick, the pre-frost boll rate is 91.0%, fiber length is 31.1 mm, fiber quality is excellent, making it a high-quality cotton variety. The growth period is 125 days, plant height 110-130 cm. Comprehensive traits are stable, with outstanding disease resistance and insect resistance. In particular, the boll type is extra-large and eye-catching, with many five-locule bolls, strong boll setting, concentrated boll setting, and fast boll development. The plant grows vigorously, and when planted in cotton areas it stands out clearly from a distance, especially in the golden autumn season, with abundant large bolls that are very appealing! While retaining the strong disease resistance and large bolls of the original Shuofeng No. 9, this variety also adds the traits of being easy to pick and having strong boll setting, so it will be the first choice variety for cotton farmers growing large-boll cotton to achieve high yields.

Planting key points: The frame is relatively large, suitable for sparse planting, and it likes fertilizer and water. For direct-seeded cotton fields with plastic film mulching, sow from April 20 to 25, using 700 g of seed per mu (2 bags). Apply 3000-5000 kg of base fertilizer per mu, 10 kg of urea, 20 kg of diammonium phosphate, 30 kg of potassium chloride, and 1 kg each of boron, zinc, manganese and other micro-fertilizers (for micro-fertilizers, it is recommended to use the "Cotton Disease-Resistant Yield-Increasing Agent" recommended by Fengda Company, at 800 g per mu). For simplified cultivation without pruning, the row spacing is 110 cm, plant spacing 40 cm, and about 1500 plants per mu, which can produce more than 40-50 bolls per plant and about 300 g of cotton per plant. If cultivated with pruning, keep 2600 plants per mu, with more than 30 bolls per plant and about 200 g of cotton per plant. The average seed cotton yield is 350-400 kg per mu, and under high-yield cultivation it can exceed 1000 jin. Suitable for planting in North China and the Huang-Huai cotton regions.