摘要
【目的】明确氮素水平对玉米胚乳淀粉粒分布与糊化特性的影响。【方法】以玉米杂交种郑单958为材料,设置4个氮素水平,即纯氮0 (N_0)、135 (N_1)、270 (N_2)和405 (N_3) kg/hm^2,研究施氮水平对玉米成熟期籽粒胚乳淀粉粒粒度分布和糊化特性的影响。【结果】玉米籽粒淀粉粒粒径分布范围为0.40～19.5μm。不同处理玉米籽粒淀粉粒体积分数和表面积百分比分布都呈双峰曲线,以玉米淀粉粒直径为1.5μm和12μm为界线,将成熟的玉米淀粉粒划分为小型(<1.5μm)、中型(1.5～12μm)和大型(>12μm) 3组。淀粉粒数量分布呈单峰曲线,其中小型淀粉粒数量占总数98%以上,说明玉米胚乳淀粉粒主要由小型淀粉粒组成。施纯氮0～270 kg/hm^2范围内,增施氮肥可以提高玉米籽粒小、中型淀粉粒体积分数,降低大型淀粉粒体积分数;显著降低玉米淀粉峰值黏度和保持黏度。玉米淀粉粒黏度与中、小型淀粉粒体积分数呈负相关,与大型淀粉粒体积分数呈正相关,可见玉米大型淀粉粒的淀粉黏度较小型淀粉粒高。【结论】适宜氮素水平通过调控玉米淀粉粒度分布,即增加中小型淀粉粒比例、降低大型淀粉粒比例,进而改变淀粉糊化特性,即降低了淀粉峰值黏度、保持黏度与最终黏度等参数。
[Purpose]Effects of nitrogen fertilizer on the granule size distribution and gelatinization characteristics of corn starch were determined by different nitrogen rates.[Method]Corn cultivar,‘Zhengdan 958’,was used to investigate the effect of nitrogen application rate[pure nitrogen0(N0),135(N1),270(N2)and 405 (N3)kg/hm^2]on the starch granule size distribution and gelatinization properties in corn kernels.[Result]The size of starch granule was in the range of0.40-19.5μm for‘Zhengdan 958’.The volume and surface area distribution of starch granules showed the typical two populations of starch granules.The corn starch granules were divided into three groups including small(<1.5μm),medium(1.5-12μm)and large(>12μm)starch granule groups at the maturity.A typical population of number distribution of starch granules was showed in this study.More than98%of the total number came from small starch granules,which indicated that the corn endosperm starch granules are mainly composed of small starch grains.Under the conditions of increasing nitrogen fertilizer,the percentage of medium starch granules increased significantly.The medium nitrogen led to a significant increase in volume percentage of small and medium starch granules and decline in those of large starch granules,respectively.In addition,medium nitrogen led to a significant decline the peak and trough viscosities in corn kernels.Correlation analysis showed that the peak,trough and final viscosities were negatively related to volume percentage of small and medium starch granules,and positively related to volume percentage of large starch granules.It indicated that large starch granules had more the values of gelatinization parameters.[Conclusion]The results suggested that appropriate nitrogen fertilizer increased the volume percentage of small and medium starch granules,and decreased volume percentage of large starch granules,and thus decreased peak,trough and final viscosities in corn kernels.
作者
钱必长
方连
夏澳运
李文阳
QIAN Bichang;FANG Lian;XIA Aoyun;LI Wenyang(College of Agronomy,Anhui Science and Technology University,Engineering Technology Institute of Maize Breeding in Anhui Province,Fengyang 233100,China;National Key Laboratory of Crop Biology,Shandong Agricultural University,Tai’an 271018,China)
出处
《云南农业大学学报（自然科学版）》
CSCD
北大核心
2018年第6期1011-1015,共5页
Journal of Yunnan Agricultural University:Natural Science
基金
国家自然科学基金项目(31501271)
安徽省高校优秀青年人才支持计划重点项目(gxyqZD2016218)
安徽省科技重大专项计划项目(16030701102).
关键词
玉米
氮素
淀粉粒
粒度分布
糊化特性
corn
nitrogen
starch granule
size distribution
gelatinization characteristics
