摘要
施用氮素穗肥是水稻增产的一项重要管理措施,但其用量对不同穗型超级稻品种的增产效应及其机制尚不明确。本研究选用3个穗型(以每穗粒数表示)差异较大的超级稻品种南粳9108(小穗型)、扬两优6号(中穗型)和甬优1540(大穗型)为材料,在基蘖肥用量相同(162 kg N hm^(-2))的情况下,研究了0、54、108、162和216 kg km^(-2)五种穗肥施氮量对上述水稻品种产量的影响,并观察了其对颖花分化退化及抽穗后相关形态生理指标的调控效应。结果表明:(1)在0~216 kg hm^(-2)穗肥施氮量范围内,随施氮量增加,水稻每穗粒数均逐渐增加,结实率和粒重逐渐降低,且穗肥施氮量越高结实率和千粒重下降越明显。南粳9108、扬两优6号和甬优1540三个水稻品种在穗肥施氮量分别为162~216、108~162和54~108 kg hm^(-2)时产量最高。依据产量与穗肥施氮量曲线方程计算出上述3个品种高产最适穗肥施氮量分别为177.6~182.0、134.3~136.3和109.9~125.7 kg hm^(-2)。(2)总体而言,穗型大的品种产量高,穗型小的品种穗肥增产效应大。施用穗肥后小穗型品种二次颖花分化数和现存数增加幅度大是其增产效应高于中、大穗型品种的主要原因。(3)3个水稻品种在高产的穗肥施氮量条件下,高效叶面积率、粒叶比(颖花/叶、实粒/叶和粒重/叶)、非结构性碳水化合物(non-structural carbohydrate,NSC)转运量、糖花比、抽穗后0~40 d根系氧化力、颖花根活量和籽粒与根系玉米素(zeatin,Z)和玉米素核苷(zeatin riboside,ZR)含量高。相关分析表明,不同穗型超级稻品种产量与以上指标基本呈显著或极显著正相关关系。上述结果表明,穗肥施氮量应根据穗型大小进行调节。适宜的穗肥施氮量有助于在较高总颖花量的前提下,保持抽穗后较高的高效叶面积率、粒叶比、NSC转运量、糖花比、根系氧化力、颖花根活量和籽粒与根系中Z+ZR含量,这有利于维持较高的结实率和粒重,从而提高水稻产量。
The application of panicle nitrogen fertilizer is an important management measure to increase rice yield,but its effect and mechanism of application rates on the yield increase of super rice varieties with different panicle sizes are still unclear.In this study,three super rice varieties with large differences in panicle sizes(indicated by the spikelet number per panicle)of Nanjing 9108(small panicle size),Yangliangyou 6(medium panicle size),and Yongyou 1540(large panicle size)were selected as materials.Under the condition of the same amount of base-tiller fertilizer(162 kg N hm^(-2)),the effects of five panicle nitrogen fertilizer rates(PNR)of 0,54,108,162,and 216 kg hm^(-2) on the yield of the above rice varieties were studied.And its regulatory effects on the differentiation and degeneration of spikelets and related morphophysiological indices after heading were observed.The results were as follows:(1)In the PNR range of 0–216 kg hm^(-2),the spikelet number per panicle gradually increased but the seed-setting rate and 1000-grain weight gradually decreased with the increase of PNR.And the higher the PNR,the more obvious the decrease of seed-setting rate and 1000-grain weight.Three rice varieties,Nanjing 9108,Yangliangyou 6,and Yongyou 1540,had the highest yields in the PNR of 162–216,108–162,and 54–108 kg hm^(-2),respectively.According to the curve equation of grain yield and PNR,the optimal PNR for high yields of the above three varieties were calculated to be 177.6–182.0,134.3–136.3,and 109.9–125.7 kg hm^(-2),respectively.(2)In general,rice varieties with large panicle sizes had higher yields,while rice varieties with small panicle sizes had greater yield-increasing effects of PNR.The number of differentiated and surviving secondary spikelets in rice varieties with small panicle size increased greatly after application of panicle nitrogen fertilizer,which was the main reason that the yield-increasing effect was higher than that of rice varieties with medium and large panicle size.(3)Under the condition of high-yield PNR,high effective leaf area ratio,grain-leaf ratio(spikelet/leaf area,filled grain/leaf area,and grain weight/leaf area),non-structural carbohydrate(NSC)translocation amount,sugar-spikelet ratio,root oxidation activity,activity root of spikelet and zeatin(Z)+zeatin riboside(ZR)content in grains and roots from 0–40 day(s)after heading of three rice varieties were high.Correlation analysis showed that the yields of super rice varieties with different panicle sizes and the above indicators basically had a significant or extremely significant positive correlation.These results indicated that the PNR should be adjusted according to the panicle size.The appropriate PNR was beneficial to maintain a high effective leaf area ratio,grain-leaf ratio,NSC translocation amount,sugar-spikelet ratio,root oxidation activity,activity root of spikelet,and Z+ZR content in grains and roots after heading under the premise of higher total spikelets.This helped to maintain a high seed-setting rate and grain weight,thereby ultimately increasing the grain yield.
作者
刘昆
黄健
周沈琪
张伟杨
张耗
顾骏飞
刘立军
杨建昌
LIU Kun;HUANG Jian;ZHOU Shen-Qi;ZHANG Wei-Yang;ZHANG Hao;GU Jun-Fei;LIU Li-Jun;YANG Jian-Chang(Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Co-innovation Centre for Modern Production Technology of Grain Crops/Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding,Yangzhou University,Yangzhou 225009,Jiangsu,China)
出处
《作物学报》
CAS
CSCD
北大核心
2022年第8期2028-2040,共13页
Acta Agronomica Sinica
基金
国家自然科学基金项目(32071947,31871557)
江苏省农业科技自主创新项目(cx(18)3007)
江苏省作物遗传生理重点实验室开放课题(YSCL201807)
国家重点研发计划项目(2016YFD0300502,2017YFD0301206)
江苏高校优势学科建设工程项目(PAPD)
江苏省研究生科研与实践创新计划项目(KYCX21_3235)资助。
关键词
水稻
穗肥施氮量
穗型
高产
形态生理
rice
panicle nitrogen fertilizer rate
panicle size
high yields
morphology and physiology
