成都平原两熟区水氮管理模式与磷钾肥配施对杂交稻冈优725产量及品质的影响

Effects of water-nitrogen management patterns and phosphorus and potassium fertilizer combined application on grain yield and quality of hybrid rice Gangyou 725 in rapeseed( wheat)- rice planting area of Chengdu plain

以杂交稻冈优725为材料，通过“淹水灌溉＋氮肥优化运筹（W1N1）”、 “控制性交替灌溉＋氮肥优化运筹（W2N1）”、 “旱种＋氮肥优化运筹（W3N2）”3 种水氮管理模式及不同的磷钾肥配施处理，研究其对成都平原两熟区水稻产量、 养分分配及品质的影响。结果表明，水氮管理模式和磷钾肥配施对稻米品质、 稻株各营养器官养分分配及产量均存在显著影响；水氮管理模式对稻谷产量、 整精米率、 直链淀粉、 蛋白质及RVA谱影响明显高于磷钾配施处理，而磷钾肥配施对垩白度、 垩白粒率、 胶稠度的调控作用显著。W2N1相对于W1N1及W3N2水氮管理模式的水稻产量分别提高3.02%和28.21%，为本试验最优的水氮管理模式，且与施磷量P2O5 90 kg/hm^2、 施钾量K2O 90~180 kg/hm^2 配施组合能进一步提高结实率和千粒重，利于成熟期籽粒氮、 磷、 钾素及稻株总养分累积量的增加，达到水肥耦合促产的目的，而且能提高整精米率、 胶稠度、 蛋白质含量，降低垩白度、 垩白粒率、 直链淀粉及消减值，改善米质。W1N1模式与P90K90配施为宜；旱种相对于淹灌下的水氮优化管理模式，不利于产量及米质的提高，但与P90K180配合对稻谷的产出及米质的改善有一定的补偿作用，可为生产中在水资源不足的情况下提供参考。

Hybrid rice Gangyou 725 was used to investigate the effects of three waternitrogen management patterns [submerged irrigation and optimized nitrogen （N） application, W1N1; controlled alternate irrigation and optimized N application, W2N1 and dry cultivation and optimized N application, W3N2] and different phosphorus （P）-potassium （K） combined application on grain yield, quality and nutrient distribution of rice in rapeseed （wheat）-rice planting area of Chengdu plain. The results show that different water-nitrogen management patterns and P-K fertilizer combined application significantly affect rice quality, nutrient absorption and distribution and grain yield. The yields, head rice rates, amylose contents, protein contents and RVA profile values under different waternitrogen management patterns are higher than those of different P-K fertilizer combined applications, while the chalkiness degrees, percentages of chalky kernel and gel consistencies are opposite. The average of grain yield is decreased under the W1N1 and W3N2 treatments （3.02% under the W1N1 treatment, 28.21% under the W3N2 treatment） compared with the W2N1 treatment. Furthermore, the W2N1 and suitable P90K90-180 combined application （P applied amount 90 kg/ha, K applied amount 90 kg/ha-180 kg/ha） would be useful to regulate seed setting rate and 1000-grain weight, enhance nutrient absorption, head rice, gel consistency, protein content, peak viscosity and breakdown, decrease chalkiness degree, percentage of chalky kernel, amylase and setback, and improve yield and rice quality. The suitable P90K90 combined application is considered to be optimum under the W2N1 Compared with the W1N1, the W3N2 results in yield reduction and bad rice quality, while the W3N2 and suitable P90K180 has compensation for yield outputs and rice quality.