杂交中稻组合的耐旱性与植株地上部性状的关系(英文)

目的]研究杂交中稻组合的耐旱性与植株地上部性状的关系,以期为抗旱水稻品种的选育提供理论和实践依据。方法]2011年以30个杂交中稻组合为材料进行大田试验,设置3个不同处理:分蘖期干旱、穗分化期干旱和对照(全生育期保持浅水层),测定水稻的主要农艺性状,并计算各品种的抗旱指数。2012年以16个杂交中稻组合为材料,进行钵栽试验,设置干旱和对照两个处理,并测定水稻的主要农艺性状,并计算各品种的抗旱指数。结果]分蘖期干旱土壤含水量达近60%,穗分化期干旱土壤含水量达近80%时,均极显著降低水稻产量。大穗和发根力强的组合,穗分化期抗旱能力强;干旱处理下产量越高的组合抗旱能力越强。分蘖期抗旱指数与穗分化期的抗旱指数无相关性。在水种条件下,千粒重较低的组合抗旱能力较强;在受旱条件下,千粒重低和产量高的组合抗旱能力强。结论]筛选出了较强抗旱能力组合有:D优6511、泰优99、内5优317、内香优18号、宜香优7633、天优华占、II优615、内香5306、川谷优7329、内香7539,可供生产上作为抗旱栽培的优选品种。

Correlations between Drought Resistance and Shoot Traits of Mid-season Hybrid Rice

Objective] This study aimed to investigate the correlations between the drought tolerance and plant traits of hybrid rice, so as to provide theoretical basis for the breeding of drought-tolerant rice varieties. Method] In the field experiment in 2011, 30 hybrid rice cultivars were grown under three different conditions： drought at til ering stage, drought at panicle initiation stage and control （keeping shal ow wa-ter during the whole growth period）. Then, the main plant traits were measured, and the related drought tolerance indices were calculated. In 2012, 16 hybrid rice culti-vars were grown in pots under drought and normal water conditions respectively. And their main plant traits were measured, and the related drought tolerance indices were also calculated. Result] The water content in soil under drought stress at til ering stage was nearly 60%, and that under drought stress at panicle initiation stage was 80%. Such low water content significantly reduced the rice yield. The cultivars with large panicle and great root growth potential had strong drought toler-ance at panicle initiation stage. Under drought stress, the cultivars with higher yield had stronger tolerance to drought. The drought tolerance indices at til ering stage had no correlations with those at panicle initiation stage. Under normal water condi-tions, the cultivars with smal er 1 000-grain weight had stronger tolerance to drought . Under drought stress , the cultivars with smal er 1 000-grain weight and higher grain yield had stronger tolerance to drought. Conclusion] Among al the rice cultivars tested in the present study, D You 6511, Taiyou 99, Nei 5 You 317, Neixiangyou 18, Yixiangyou 7633, Tianyouhuazhan, II You 615, Neixiang 5306, Chuanguyou 7329 and Neixiang 7539 exhibited better tolerance to drought, and thus can be promoted in production.