氮锌肥配施对南方香粳稻产量和品质的影响

Combined application of nitrogen and zinc fertilizer affects the yield and quality of fragrant southern japonica rice

【目的】研究氮锌肥配施对南方香粳稻产量和外观加工品质、蒸煮食味品质、香气的影响,为南方香粳稻的调优栽培提供科学依据。【方法】田间试验于2020和2021年在扬州大学试验基地进行,供试粳稻品种为宁香粳9号和南粳46。在施锌(+Zn)和不施锌(Zn0)条件下,分别设3个施氮水平:0(N0)、180 kg/hm^(2)(N180)、270 kg/hm^(2)(N270),共6个处理。于收获期,测定产量和产量构成因素,分析籽粒加工外观、食味和香气品质。【结果】提高氮肥用量可显著增加香粳稻产量,而施用锌肥对香粳稻产量无显著影响,+ZnN270处理宁香粳9号和南粳46产量均最高,分别达10.48 t/hm^(2)和10.40 t/hm^(2);相同氮肥用量下,增施锌肥对产量没有显著影响。宁香粳9号和南粳46的最佳稻米加工和外观品质均以+ZnN270处理最优。在相同氮肥用量下,施用锌肥改善了香粳稻的加工和外观品质。与N0处理相比,在N180和N270处理下两品种的直链淀粉含量下降了8.44%~13.16%,蛋白质含量增加了9.79%~23.89%,食味值显著下降。相同氮肥用量下,增施锌肥显著增加了稻米蛋白质含量,提升了食味值。香粳稻的消减值随氮肥用量的增加而增加,其余稻米米粉黏滞性谱(RVA谱)指标随氮肥用量的增加而降低;相同氮肥用量下,+Zn处理对香粳稻的RVA无显著影响。提高氮肥用量可增加香粳稻糙米和精米中氮含量和2-乙酰基-1-吡咯啉(2AP)含量,N180处理宁香粳9号和南粳46糙米中氮含量较N0处理分别增加了4.64%和4.87%,精米中氮含量分别增加了9.80%和12.88%;糙米中2AP分别增加了8.91%和41.38%,精米中2AP分别增加了7.91%和5.88%。N270处理两品种糙米中氮含量较N0处理分别增加了12.17%和11.00%,精米中氮含量分别增加了23.89%和22.98%;糙米中2AP分别增加了12.16%和91.28%,精米2AP分别增加了16.24%和120.78%。N270处理下,与Zn0处理相比,+Zn处理宁香粳9号和南粳46糙米中锌含量分别增加了1.00%和3.01%,2AP含量分别增加了0.47%和15.27%;精米中锌含量分别增加了9.75%和2.19%,2AP含量分别增加了5.71%和52.04%。【结论】较高的氮肥施用量能有效提高香粳稻产量,提升加工、外观和香气品质。高氮水平配合锌肥不仅获得更好的加工品质和外观品质,还能显著增加香气物质含量和食味值。本试验条件下,施用氮270 kg/hm^(2)并配施锌肥是实现香粳稻产量高、加工外观品质好、蒸煮食味品质佳的施肥方式。

【Objectives】The effects of nitrogen rate and zinc fertilizer on the yield,processing and appearance quality,cooking taste,and aroma of fragrant southern japonica rice were studied.【Methods】A field experiment was conducted in the experimental base of Yangzhou University,two fragrant japonica rice cultivars,Ningxiangjing 9 and Nanjing 46,were used as experiment materials.The tested N application levels were 0(N0),180(N180),and 270(N270)kg/hm^(2) under both applying Zn fertilizer(+Zn)and no Zn fertilizer conditions.At maturing stage,the yield,yield compomemts,grain processing,tasting and fragrance quality were determined.【Results】Higher N rate produced higher rice yield,N270 treatment gave the highest yield in Ningxiangjing 9(10.48 t/hm^(2))and Nanjing 46(10.40 t/hm^(2)),+Zn did not affect rice yield.N270 elicited higher rice processing and appearance quality than N0 and N180,and+Zn improved the processing and appearance quality of rice under the same N fertilizer rate(P<0.05).The highest processing quality of Ningxiangjing 9 and Nanjing 46 rice were recorded under+ZnN270.Compared with N0,N180 and N270 increased the protein content by 9.79%−23.89%,but decreased the amylose content by 8.44%−13.16%as well as the taste value significantly.Under the same N rate,+Zn increased rice protein content and improved taste value.The setback value of rice increased,while other indicators of the rheological viscoelasticity value(RVA)decreased with the increase of N application rate.Under the same N fertilizer rate,+Zn did not affect RVA of rice flour(RVA spectrum),compared with no Zn application.The nitrogen and 2-acetyl-1-pyrrololine(2AP)content in brown rice and milled rice increased with increasing N application rate.Compared with N0,N180 increased the nitrogen content of brown rice in Ningxiangjing 9 and Nanjing 46 by 4.64%and 4.87%,increased the nitrogen content of milled rice by 9.80%and 12.88%;increased 2AP content in brown rice by 8.91%and 41,38%,and increased 2AP content in milled rice by 7.91%and 5.88%,respectively.Compared with N0,N270 increased the nitrogen content of brown rice in two cultivars by 12.17%and 11.00%,increased the nitrogen content of milled rice by 23.89%and 22.98%;increased 2AP content in brown rice by 12.16%and 91.28%,and increased 2AP content in milled rice by 16.24%and 120.78%,respectively.Under N270,compare to Zn0,+Zn treatment increased the Zn content in brown rice of Ningxiangjing 9 and Nanjing 46 by 1.00%and 3.01%,increased the 2AP content in brown rice by 0.47%and 15.27%;increased the Zn content in milled rice by 9.75%and 2.19%,and increased the 2AP content in milled rice by 5.71%and 52.04%,respectively.【Conclusions】A relatively high rate of nitrogen fertilizer is beneficial for the yield,processing quality,and the aroma of milled rice(2AP value).Combined application of N with Zn fertilizer does not decrease the benefit of high N fertilizer,it rather increases the appearance quality and further improves the aroma of milled rice significantly.The recommended fertilization method for fragrant japonica rice is N 270 kg/hm^(2) combined with zinc fertilizer,for an optimally high yield,good processing quality and cooking taste.