A breeding method for cultivating japonica rice varieties with high nitrogen utilization

Abstract

The invention discloses a breeding method for cultivating japonica rice varieties with high nitrogen utilization efficiency. The early-growing and fast-growing japonica rice variety with both panicle and grain is used as the female parent, and the japonica rice variety with both panicle and grain is used as the male parent. F 0 -F 3 Rare live planting, mixed species; F 4 The above generations are sparsely sown and raised seedlings, transplanted and planted in a single copy, and kept in a single plant. Nitrogen was reduced by seedling fertilizer and basal tiller fertilizer, with the average number of stems and tillers per plant 25-30 days after sowing and the average number of spikes per plant at the mature stage as the selection pressure, according to the pedigree method F 5 Establish strains together, select the best among the best, until a stable strain is obtained and promoted to participate in intermediate tests at all levels. The japonica rice varieties cultivated by the present invention can realize the cultivation of strong seedlings, early growth and rapid growth, and early enough seedlings under the condition of greatly "reducing nitrogen" in seedling fertilizer and basal tiller fertilizer, ensuring that the number of stems and tillers reaches a suitable number in the effective tillering period, and finally realizes The purpose of "weight loss" and "reduction of medicine" in rice production is to improve quality and increase efficiency.

Description

technical field [0001] The invention relates to the field of breeding methods, in particular to a breeding method for cultivating japonica rice varieties with high nitrogen utilization. Background technique [0002] Nitrogen, phosphorus, and potassium are macroelements necessary for the growth and development of rice, especially nitrogen, which is applied in the largest amount throughout the life of rice. In the middle and lower reaches of the Yangtze River, the yield per mu of japonica rice is 600kg, and the amount of nitrogen used is generally 18-20kg / mu. Then increase again and again. Although applying more nitrogen fertilizers is conducive to high and super high yields, with the increase of nitrogen input level, the effect of increasing nitrogen production and the input-output ratio are constantly declining. In addition, because the nitrogen use rate is only 30%-35%, Excessive and lost nitrogen can easily lead to eutrophication of water bodies, resulting in large-scale...

AI Technical Summary

Problems solved by technology

[0006] Obviously, the reduction of nitrogen in rice seedling fertilizer and basal tiller fertilizer is not conducive to the cultivation of strong seedlings with tillers, early growth and rapid emergence of tillers, early enough seedlings and tillering into spikes, and is not conducive to high and stable yields.

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