不同形态氮素配比对杂交粳稻根系及收获指数的影响

Effects of different nitrogen form ratios on root and harvest index of Japonica hybrid rice

采用供应不同形态氮素配比(NH4+-N∶NO3--N分别为3∶1、1∶1、1∶3)对杂交粳稻组合滇杂31及其亲本进行水培培养,在抽穗期对试验材料根系性状、生物量及成熟期生物产量、单株粒重和收获指数进行比较及优势效应分析。结果表明:所有材料根系性状、生物产量及单株粒重均随着硝态氮比例的增加而显著增加,然而收获指数却随硝态氮的增加而显著下降。杂交粳稻组合根系性状、生物量、单株粒重及收获指数在各种形态氮素配比处理下均明显优于其亲本和对照品种。通过t测验表明,在不同氮素配比处理下,杂交组合超亲优势和对照优势效应均达显著或极显著水平,其中绝大多数性状在NH4+-N∶NO3--N为3∶1或1∶1处理中具有较高的相对优势值,而生物产量在NH4+-N∶NO3--N为1∶3的处理中表现出最高相对优势。优良的杂交粳稻对氮素环境的适应性比优良常规粳稻品种更好。

Japonica hybrid rice combination Dianza 31 and its parents were used in hydroponic experiment by supplying different N form ratios （NH3^＋-N/NO4^--N was 3：1, 1：1 and 1：3）, and the root traits and biomass at heading stage and the biomass and grain weight per plant and harvest index at maturity stage were determined and analyzed. The results showed that the root traits, biomass and grain weight per plant of experimental materials were obviously increased with the increase of nitrate nitrogen ratio, while the harvest index was decreased. The root traits, biomass and grain weight per plant and harvest index of the hybrid combination were better than those of its parents and the control. Moreover, the effects of heterobeltiosis and control heterosis of the hybrid combination reached significant or very significant difference in T-test. When the ratio of NH4^＋-N to NO3^--N was 3：1 or 1：1, the relative heterosis of most traits of rice was higher, while that of biomass was the highest when the ratio of NH4^＋-N to NO3^--N was 1：3. Therefore, the adaptability to nitrogen environment of Japonica hybrid rice with high-quality was better than that of conventional Japonica rice with high-quality.