两系杂交早稻父本996孕穗期和开花期耐冷性评价

Evaluation of Cold Tolerance of Early Two-line Hybrid Rice Male Parent 996 at Booting and Flowering Stages

以水稻品种4628(耐冷性弱)和丰源B(耐冷性较强)为对照,采用人工气候室低温处理对两系杂交早稻父本996孕穗期和开花期的耐冷性进行了鉴定评价。结果表明,996孕穗期低温处理下的结实率和相对结实率显著高于对照品种4628,结实率下降值和低温敏感指数显著低于对照品种4628;996开花期低温处理下的结实率和相对结实率显著高于对照品种丰源B和4628,结实率下降值和低温敏感指数显著低于对照品种丰源B和4628。说明996孕穗期的耐冷性显著强于对照品种4628,开花期的耐冷性显著强于对照品种4628和丰源B。

Using rice varieties 4628 （cold susceptible） and Fengyuan B （cold tolerant） as the checks,the cold tolerance of 996,a early two-line hybrid rice male parent,at booting and flowering stages were studied under low temperature stress conditions in phytotron.The results showed that,under cold stress treatments at booting stage,996 was significantly higher than 4628 in the seed-setting rate and relative seed-setting rate,but lower than 4628 in the reduced value of seed-setting rate and cold susceptibility index.Under cold stress treatments at flowering stage,the seed-setting rate and relative seed-setting rate of 996 were significantly higher than those of the checks Fengyuan B and 4628 while the reduced value of seed-setting rate and cold susceptibility index of 996 were significantly lower than those of the checks Fengyuan B and 4628.It is indicated that 996 has a stronger cold tolerance than 4628 at booting stage and than both 4628 and Fengyuan B at flowering stage.