Key Cultivation Techniques for Rice Variety II You 084
II You 084 is a new hybrid indica rice variety bred by the Zhenjiang Institute of Agricultural Sciences in Jiangsu. It shows high resistance to bacterial leaf blight and rice blast. It participated in the Jiangsu Province hybrid indica rice regional trial from 1999 to 2000, was exceptionally admitted to the Jiangsu Province production trial in 2000, and passed the approval of the Jiangsu Province Crop Variety Approval Committee in April 2001. It passed national approval in November 2003. On September 6, 2003, it set a new world record for rice yield per unit area at 1231.17 kg/mu. It is exclusively developed by Jiangsu Mingtian Seed Industry Technology Co., Ltd. Characteristics and traits: The whole growth period is about 145 days, maturing 2 to 3 days later than Shanyou 63. When sown in Nanjing on May 10, it begins heading from August 16 to 20 and reaches full heading from August 18 to 22; when sown in Yancheng on April 30, it begins heading from August 14 to 18 and reaches full heading from August 17 to 21; when sown in Xuzhou and other places on May 10, it begins heading from August 19 to 23 and reaches full heading from August 21 to 25.
Agronomic traits: Good plant type, luxuriant growth, strong tillering ability, and easy to cultivate. Plant height is about 120 cm, similar to Shanyou 63, with thick and sturdy stems and strong lodging resistance. Large panicles with many grains, high seed-setting rate, good yield performance, and great yield potential. Generally 2.4 million to 2.7 million panicles per hectare, panicle length 24 cm to 25 cm, about 180 total grains per panicle, seed-setting rate about 90%, and 1000-grain weight 27 g to 28 g.
Disease resistance: This combination is highly resistant to bacterial leaf blight and rice blast, with light sheath blight, clean growth, and good maturity appearance. In 1999, the Institute of Plant Protection of the Jiangsu Academy of Agricultural Sciences used 4 bacterial leaf blight strains including KS-6-6, Zhe 173, PX079, and JS49-6 for inoculation identification, and the disease grades were 1, 3, and 1 respectively (special); using 5 physiological races of rice blast including Zhong D1, Zhong E3, Zhong B6, Zhong C1, and Zhong F1 for inoculation identification, all disease grades were 0.
Quality: Tested by the Rice and Rice Products Quality Supervision and Inspection Testing Center of the Ministry of Agriculture, the brown rice rate is 82.4%, milled rice rate 75.9%, head rice rate 67.7%, grain length 6.3 mm, length-to-width ratio 2:6, alkali spreading value grade 4.4, gel consistency 44 mm, chalkiness 15.7%, amylose content 21.4%, protein content 11.7%, and transparency grade 2. It reaches Grade 2 of the Ministry of Agriculture industry standard.
Key cultivation techniques: For sowing and seedling raising, it is essential to sun the seeds before sowing, select seeds to promote uniform emergence; soak seeds with chemicals to prevent and control pests and diseases; and use sparse sowing with sufficient fertilizer and fine management to raise strong seedlings. II You 084 belongs to the medium-maturing medium indica type. For wet seedling raising in southern Jiangsu, sowing is generally done in early May, and the seedling age should preferably be controlled at 30-35 days. Sow 150-225 kg per hectare of seedling field, and use about 15.0 kg of seed per hectare of main field. In the seedling field, after plowing and freezing the ridges before winter, finely preparing the seedling field, and applying sufficient basal fertilizer, apply the weaning fertilizer early at the 1-leaf-1-heart stage, generally using 90-120 kg of urea and 45-75 kg of potassium fertilizer per hectare; at the 3-leaf stage, apply a supplementary relay fertilizer, and strengthen water field management and the prevention and control of diseases, insects, and weeds to cultivate age-appropriate strong seedlings with tillers. For dry seedling raising in fertilized beds, sowing is generally done from May 10 to 15, with about 450 kg sown per hectare of seedling field. And effectively implement the technical measures for seedbed fertilization and dry seedling raising.
Planting density: Reasonable close planting, uniform and shallow transplanting, and improved transplanting quality. For fields with medium to high fertility, plant 240,000-270,000 hills per hectare. With a plant-row spacing of 13 cm x 28 cm, 1-2 seedlings per hill, and about 750,000 basic seedlings per hectare; for fields with poorer fertility, plant 300,000 hills per hectare, with a plant-row spacing of 13 cm x 25 cm, and about 1.05 million-1.2 million basic seedlings/hm2. For dry seedling raising, the number of basic seedlings can be appropriately reduced.
Fertilizer and water management: The yield level of II You 084 is higher than that of Shanyou 63. Its fertilizer requirement level is also slightly higher than that of Shanyou 63. Generally, about 225 kg of nitrogen is applied per hectare, with a combination of nitrogen, phosphorus, and potassium. The strategy for fertilizer and water management should follow the principle of promoting early, controlling mid-season, and stabilizing late. It requires sufficient basal fertilizer and early and heavy application of tillering fertilizer. Irrigate frequently with shallow water to promote early development; on the basis of mid-season control, apply sufficient panicle fertilizer, giving consideration to both promoting and preserving, with promotion as the main focus, and attention should be paid to the use of potassium fertilizer in panicle fertilizer; in the later stage, adopt an alternating dry and wet method, and be careful not to cut off water too early, so as to ensure living maturity, high yield, and good quality.
Pest and disease control: Carry out timely control according to the occurrence patterns of diseases, insects, and weeds. Especially under high-yield cultivation conditions, due to the relatively high nitrogen level, attention should be paid to the control of rice leaf roller, striped stem borer, rice planthopper, and weeds.