D you 448 (Rice)

[basic situation] D you 448 is a new hybrid rice combination with good quality, high yield, middle and late rice, which was bred by crop Research Institute of Sichuan Academy of Agricultural Sciences with D62A and self-selected wide compatibility restorer line Chenghui 448.

[characteristics] the combination participated in the regional trial of medium indica maturity group in Sichuan Province from 1999 to 2000, and the average yield of 2 years was 8.14t/hm2, which was 5.95% higher than that of the control. In the provincial production test in 2000, the average yield of 8.26t/hm2 was 9.47% higher than that of the control. In 2000, he participated in the national regional trial of late rice in the southern rice region, and the average yield was 6.82t/hm2, 1.86% higher than that of the control.

D you 448 as medium rice, the whole growth period is 148.5 days, which is 5-6 days shorter than that of Shanyou 63, plant height 100cm, panicle length 25cm, effective panicle 2.562 million / hm2, panicle rate 84%, average grain setting rate 84.17%, 1000-grain weight 27.1g. Cultivated as late rice, the whole growth period was 125.5 days, 1.7 days longer than the control, plant height 92.6cm, panicle length 24cm, total grains per panicle 108.3 grains, seed setting rate 79.9%, 1000-grain weight 27.4g. The combination has strong tillering ability, coordinated grain weight per ear, thick green leaf color, tight and scattered plant type, wide, short, thick and straight flag leaves, and good lodging resistance.

According to the identification of 4 rice blast resistance identification units designated by the Sichuan Provincial Regional Test, from 1999 to 2000, Dyou 448 had an average of 4 grades of leaf blast (Oasis 7), 5 grades of cervical blast (Orange 7), and 12% of the incidence of cervical blast (41%). The control average leaf blast grade 7 (range 3-9), neck blast grade 7 (range 3-9), neck blast incidence 45% (range 7.4%-92.0%). According to the national regional test, the average blast resistance of D you 448 was 5 (range from 2.1 to 7.0).

According to the test by the Rice and products quality Supervision, Inspection and Test Center of the Ministry of Agriculture, D you 448 has brown rice rate of 80.2%, milled rice rate of 73%, head rice rate of 55%, grain length 6.7mm, aspect ratio of 2.9%, chalkiness rate of 57%, chalkiness of 11.1%, transparency of grade 2, alkali elimination value of grade 6.4, gel consistency 51mm, amylose content of 21%, and protein content of 10.6%. Among them, the five indexes of milled rice rate, grain length, alkali elimination value, amylose content and protein content reached the first class standard of high quality rice issued by the Ministry, while the five indexes of brown rice rate, head rice rate, ratio of length to width, transparency and gel consistency reached the second grade standard of high quality rice issued by the Ministry.

Crop Research Institute of Sichuan Academy of Agricultural Sciences

[region and technology] D you 448 can be used as mid-mature hybrid rice and late-maturing hybrid rice.

Sow seeds at the right time and cultivate more tillers and strong seedlings. Cultivated as medium rice, sown from the end of March to early April, and cultivated as late rice, sown in mid-June. Two-stage seedling raising, wet seedling raising with plastic film or dry seedling raising can be used to cultivate multi-tiller and strong seedlings.

Proper close planting. Planting 225000 ~ 270000 holes / hm2, basic seedlings 1.8 million / hm2.

Scientific fertilization. Medium fertility fields, generally apply pure nitrogen 150~180kg, phosphate fertilizer 450~525kg, potassium fertilizer 300kg per hectare. Heavy bottom early pressure, 80% as base fertilizer, 20% as topdressing.

Pay attention to the prevention and control of diseases and insect pests and control diseases and insect pests in time according to the forecast of the local plant protection department.

Main technical points of seed production: Chenghui 448 was sown in spring in Chengdu, the initial sowing period was 102 days, which was 7 days shorter than that of Minghui 63, and the average main stem leaf was 15.5 leaves, less 1.O~1.5 leaves than Minghui 63. The pollen quantity is sufficient, the pollen density is high, the pollen dispersal is good, the florescence is 10-14 days, the flowering time is more concentrated, the sunny day 11-30-12-30 is the full flowering stage. When Chenghui 448 and D62A were used in seed production, the sowing difference of parents was 7~1Od.