杂交稻广优673高产栽培因子优化与抗瘟性分析

High-yield Cultivation Factors Optimizing and Blast-resistance Analysis for Hybrid Rice Variety Guangyou 673

【目的】分析杂交稻品种广优673的栽培试验技术和稻瘟病抗性基因的来源,为水稻抗病新品种选育和广优673推广种植提供依据。【方法】以广优673为试验材料,运用最优设计进行密度、施氮量、秧龄3项栽培因子试验,建立产量与3项措施的回归模型,分析栽培措施对产量的影响,并利用稻瘟病抗性基因Pi2、Pi9和Pigm已开发的功能标记,开展稻瘟病抗性基因的分析和检测。【结果】广优673水稻秧龄短的,早插本田生长期长,需施用较多氮肥,有利于高产;而秧龄长的,本田生长期相应短些,不需施用过多的氮肥。密度、施氮量、秧龄3项栽培因子对广优673的产量都有影响,综合高产栽培措施为:每公顷插20.52万-27.48万丛,每公顷施纯氮144.70-183.76 kg,秧龄26-33 d。稻瘟病抗性基因检测与分析表明广优673含有稻瘟病抗性基因Pi2。【结论】杂交稻广优673具有高产、抗病、生育期适中等特点,产量≥8 250 kg·hm^(-2)的栽培因子模拟寻优结果为:每公顷插24.00万丛,每公顷施纯N 164.23 kg,秧龄29.5 d,并推测稻瘟病抗性主要来源于稻瘟病抗性基因Pi2。

【Objective】 In this study, essential agronomical practices of the hybrid rice variety Guangyou 673 and its resistance to rice blast were analyzed to provide a scientific basis for breeding new rice varieties with improved diseaseresistant and to further expand the cultivation of Guangyou 673 variety. 【Methods】 Guangyou 673 was introduced for cultivation in Anxi County of Fujian Province. The impact of three essential agronomical practices, i.e., planting density(x1),nitrogen fertilization rate(x2) and seedling age(x3), on the performance of Guangyou 673 was evaluated. Regression models between grain yield and the above three agronomical factors were estimated to analyze the impact of agronomical practices on grain yield. The developed functional markers of the rice blast-resistance genes Pi2, Pi9 and Pigm were used to identify the blast-resistance genes in the genetic background of Guangyou 673.【Results】 All the three studied agronomical practices revealed significant effects on grain yield of Guangyou 673. The results showed that shortening the seedling age which was with a long growth period necessitates more nitrogen fertilization to achieve higher grain yield. On the contrary, lengthening the seedling age which was with shorter growth period required less nitrogen fertilization. The maximum grain yield was achieved when planting density ranged from 2.052–2.748×10^(6) clusters per ha, N fertilizer 144.70–183.76 kg·hm^(-2), and seedling age ranged from 26–33 days. Genotyping of Guangyou 673 with the functional molecular markers of Pi2, Pi9 and Pigm genes revealed that the variety Guangyou 673 contained the Pi2 blast-resistance gene.【Conclusion】 Hybrid rice variety Guangyou 673 had great characteristics of high grain yield, blast resistance and moderate growth period. The high yield more than 8 250 kg·hm^(-2) could be achieved with N fertilizer 144.70–183.76 kg ·hm^(-2), average plant density 2.4×10^(6) clusters per ha, and growth period 26–33 days. The results further suggested that Pi2 gene maybe the main source of blast resistance in Guangyou 673.