不同时期施用锌硅肥对优良食味粳稻产量和品质的影响

以优良食味粳稻代表品种南粳2704和南粳9108为试验材料,设置在移栽期、有效分蘖期、倒四叶期、倒二叶期分别单施锌肥、单施硅肥、锌硅肥配施处理,比较其对产量和品质的影响。结果表明,与不施锌硅肥相比,不同时期施用锌硅肥均能提高优良食味粳稻产量,倒四叶期施用锌肥产量最高,2015年与2016年南粳2704增产4.70%、7.82%,南粳9108增产5.50%、5.39%。各处理的水稻平均产量呈单施锌肥单施硅肥锌硅肥配施。在倒四叶期单施锌肥和锌硅肥配施产量最高,而在有效分蘖期单施硅肥产量最高。在不同时期施用锌硅肥,均能使稻米的糙米率降低,精米率和整精米率增加,同时还降低垩白率和垩白度,其中以倒二叶期施用锌硅肥显著增加粳稻外观品质。不同时期施用锌硅肥对蛋白质含量和直链淀粉含量的影响因处理而异,但均能增加稻米的胶稠度、口感、食味值、最高黏度和崩解值,降低消减值,其中以倒二叶期施用锌硅肥效果最为显著。相关分析表明,最高黏度、崩解值和消减值与蒸煮食味品质中的直链淀粉含量、胶稠度、口感和食味值显著或极显著相关。由此可见,在倒四叶期施用锌肥能提高优良食味粳稻产量;倒二叶期施用锌硅肥能提高稻米的蒸煮食味品质。

Effect of Zn and Si Fertilizers Applied at Different Stages on Yield and Quality of Japonica Rice with Good Eating Quality

Two representative japonica rice cultivars with good eating quality, Nanjing 2704 and Nanjing 9108, were adopted with treatments of applying Zn, Si and Zn plus Si fertilizers at transplanting stage, productive tillering stage, and the tages of growing the fourth and the second leaves from top respectively. Compared with treatments of no Zn and Si fertilizers, Zn and Si fertilizers applyed at different stages could increase the yield of japonica rice with good eating quality. Among them, the yield of treatment using Zn fertilizer at the tage of growing the fourth leaf from top was the highest. The yield increased by 4.70% in 2015 and 7.82% in 2016 for Nanjing 2704, and by 5.50% in 2015 and 5.39% in 2016 for Nanjing 9108. In different treatments, the average yield of rice showed a trend of, Zn fertilizer > Si fertilizer > Zn plus Si fertilizers. The highest yield was obtained when the Zn or Zn plus Si fertilizers were applied at the stage of growing the fourth leaf from top, on when the Si fertilizer was applied at the productive tilling stage. Zn and Si fertilizers applied at different stages could decrease brown rice rate and increase milled rice rate and head rice rate of the milling quality. Meanwhile, the chalky grain rate and chalky degree were also decreased by using Zn and Si fertilizers. In different treatments, the appearance quality of rice was greatly improved when Zn plus Si fertilizers applied at the stage of growing the second leaf from top. Of protein and amylose contents varied with treatments, while gel consistency, taste, taste value, peak viscosity and break down increased and set back decreased with the application of Zn and Si fertilizers, particularly with the application of Zn plus Si fertilizers at the stage of growing the second leaf from top. Correlation analysis revealed that peak viscosity, break down and set back were closely correlated to amylose content, gel consistency, taste and taste values of cooking quality. Therefore, the application of Zn and Si fertilizers at different stages could improve the yield and quality of japonica rice with good eating quality. In japonica rice with good eating quality, the highest yield could be obtained when Zn fertilizer applied at the stage of growing the fourth leaf from top, and the best cooking and eating quality could be achieved when Zn plus Si fertilizers applied at the stage of growing the second leaf from top.