Characteristics and High-Yield Cultivation Techniques of the New Hybrid Indica Rice Combination 29 You 559
29 You 559 is a new three-line hybrid indica rice combination bred by Jiangsu Xuzhou Higher Vocational School of Bioengineering and the Jiangsu Coastal Area Institute of Agricultural Sciences by crossing the self-bred male sterile line 29A with the self-bred restorer line Yanhui 559. 29A is the first indica three-line male sterile line bred in Jiangsu, and the new combination 29 You 559, developed by crossing 29A with Yanhui 559, shows obvious heterosis and passed the Jiangsu Provincial Crop Variety Approval in January 2003. Heterosis performance of 29 You 559
In 1999, it participated in the Jiangsu Provincial Hybrid Indica Rice Joint Identification Trial, with an average yield of 9.35 t/ha, 13.37% higher than the control Shanyou 63 (highly significant), ranking first among 11 tested combinations. In 2001, it participated in the Jiangsu Provincial Hybrid Indica Rice Regional Trial, with an average yield of 9.96 t/ha, 10.54% higher than the control Shanyou 63 (highly significant), ranking first; in 2002, in the continued trial, the average yield was 10.26 t/ha, 12.26% higher than the control Shanyou 63 (highly significant), also ranking first; the average yield over the two years of Jiangsu Provincial Regional Trials in 2001 and 2002 was 10.11 t/ha, 11.41% higher than the control Shanyou 63 (highly significant), ranking first, and its absolute yield level was the highest among combinations in the Jiangsu Provincial Hybrid Indica Regional Trials over the years. In 2002, while participating in the provincial regional trial, it exceptionally entered the Jiangsu Provincial Hybrid Indica Production Trial, with an average yield of 9.42 t/ha, 10% higher than the control Shanyou 63.
2 Characteristics of 29 You 559
29 You 559 has short, sturdy, and compact seedlings, relatively short and upright leaves, purple leaf sheaths, and slightly dark leaf color; the mature plant architecture is moderately compact, with a plant height of about 120 cm, a total of 18-19 leaves on the main stem, 5 elongated internodes, medium tillering ability, and a high productive panicle rate. Generally, the effective panicles are about 2.4 million/ha, the productive panicle rate is 65%, the panicle length is 24.5 cm, the panicle type is relatively large, the total grains per panicle are 170-180, the filled grains per panicle are about 160, the seed-setting rate is about 90%, the 1000-grain weight is 29-30 g, and the grains are yellow, plump, and awnless. The whole growth period is about 145 days, 3-4 days later than Shanyou 63, with good maturity appearance.
It is resistant to multiple diseases. According to inoculation identification by the Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences: it is resistant to 5 physiological races of rice blast, including Zhong B5, Zhong C13, Zhong D1, Zhong E3, and Zhong C1, with response grades all at level 0; resistant to panicle neck blast, with a response grade of level 1; resistant to 2 pathogenic strains of bacterial leaf blight, including JS49-6 and PX079, with a response grade of level 3; moderately resistant to sheath blight, and inoculation identification showed that the ratio of lesion expansion length to the corresponding plant height was 0.298. The rice quality is above average. Tested by the Rice and Rice Products Quality Supervision and Testing Center of the Ministry of Agriculture, the brown rice rate was 80.8%, milled rice rate 74.0%, head rice rate 58.8%, grain length 6.2 mm, length/width 2.4, chalkiness rate 79%, chalkiness degree 11.8%, transparency grade 2, alkali spreading value 4.6, gel consistency 88 mm, amylose content 22.4%, and protein content 8.5%. According to the Ministry of Agriculture standard NY1222-86 "Quality Edible Rice Standard", among the above 12 indicators, except for the 2 indicators of chalkiness rate and chalkiness degree, 10 indicators reached the high-quality rice standard.
3 High-Yield Cultivation Techniques for 29 You 559
29 You 559 belongs to the heavy-panicle type. The suitable panicle and grain structure for a yield of 9.75 t/ha is: effective panicles 2.25-2.4 million/ha, total grains per panicle more than 170, seed-setting rate about 90%, and 1000-grain weight 29-30 g. The high-yield cultivation strategy is to strive for sufficient panicles while focusing on large panicles and improving the seed-setting rate. In cultivation, regulation should be carried out around the principles of "promoting early seedling development in the early stage to lay the foundation for sufficient panicles, strengthening stems and healthy plants in the middle stage to promote large panicle formation, and nurturing roots and protecting leaves in the late stage to improve the seed-setting rate and increase grain weight." Specific measures should focus on the following points:
3.1 Early sowing at the appropriate time and cultivation of strong seedlings 29 You 559 is planted as middle rice after wheat in Jiangsu, and the best sowing period is from the end of April to early May. The seeding rate in the seedling field is 225 kg/ha for wet seedling raising and 300 kg/ha for dry seedling raising, and the seed rate for the field is 18.0-22.5 kg/ha. The seedling field should be given sufficient basal fertilizer, early weaning fertilizer, appropriate tillering-promoting fertilizer, and skillful pre-transplanting fertilizer, so as to cultivate strong seedlings with multiple tillers at the appropriate age (seedling age about 35 days).
3.2 Timely transplanting and rational close planting Transplant in early to mid-June. For fields with medium and above fertility, the planting density is 270,000 hills/ha, with 1-2 seedlings per hill, and the basic seedlings are 1.05-1.2 million/ha.
3.3 Rational fertilizer and water management and coordination of the population For cultivation at 9.75 t/ha, the total fertilizer requirement of the field is equivalent to 300 kg/ha of pure nitrogen, and fertilizer management should grasp the ratio of basal fertilizer, tillering fertilizer, and panicle fertilizer as 4:3:3. Water management should adopt the method of "shallow water for transplanting, 1 cun of water for seedling establishment, thin water for tillering, keeping water for heading and flowering, and alternating wet and dry irrigation for grain filling." When the total stems and tillers per mu reach the equal-panicle seedling number, drain and sun the field, controlling the peak seedling number not to exceed 3.75 million/ha, and finally forming 2.25-2.4 million productive panicles/ha.
3.4 Control diseases and pests, protect seedlings and increase panicles During the growth period, attention should be paid to the control of diseases and pests such as rice thrips, stem borers, and sheath blight, so as to ensure normal growth of rice seedlings.