摘要
通过系统分析2个品种与2个施氮水平的试验资料,确立了小麦穗籽粒数、单粒重、单粒蛋白质含量与蛋白质产量的小穗位和粒位效应。结果表明,不同小穗位结实籽粒数、小穗重,不同粒位粒重、单粒蛋白质含量与蛋白质产量均呈现二次曲线分布。2个品种穗部籽粒的分布存在显著差异,多粒型品种在不同施氮水平下每小穗结实粒数、单粒粒重与蛋白质含量的变化显著大于少粒型品种,高氮处理缩小了品种间的这种差异。不同粒位粒重、单粒蛋白质含量与蛋白质产量因小穗结实粒数的不同表现出不同的小穗位和粒位效应。结实2粒的小穗上,粒重、单粒蛋白质含量与蛋白质产量均表现为第1粒位大于第2粒位;位于基部的3粒小穗上,第2粒位的粒重大于第1粒位,而第1粒位的粒重又大于第3粒位,位于上部的3粒小穗上,则表现为第1粒位的粒重大于或等于第2粒位,第3粒位的粒重最小,结实3粒小穗的单粒蛋白质含量表现为第2粒位大于第1粒位,而第1粒位又大于第3粒位;结实4粒、5粒的小穗上不同粒位粒重均表现为第2粒位大于第1粒位,第1粒位大于第3粒位,而第3粒位又大于第4粒位,第5粒位的粒重最小,单粒蛋白质含量则表现为随粒位升高逐渐降低。表明第2粒位籽粒发育的变异性是决定不同条件下籽粒结实与物质积累空间分布的主要因素。
Grain development on wheat spike is asynchronous. The grain number,weight and protein content in different spikelet positions significantly varied with wheat cultivars and nitrogen levels. The experiment with two cultivars and two nitrogen levels was conducted at Nanjing from 2000 to 2001. The results showed that grain number,weight and protein content in different spikelet positions showed parabolic changes. The differences of the 3 parameters were larger in the cultivar with more grains on spike under different nitrogen levels,compared with the cultivar with fewer grains on spike,and the differences between cultivars were reduced with increasing nitrogen application. The effects of spikelet and grain positions on the weight,protein content and protein weight of individual grain varied with the grain number of spikelets. For 2 grain-set spikelets,the grain weight,protein content and protein weight in the first grain (1 st) position were higher than that in the second grain position (2 nd) (Fig.7,13). For the basic 3 grain-set spikelets,grain weight in 2 nd position was the highest,followed by that in 1 st and the third grain (3 rd) positions while grain weight in 1 st position≥that in 2 nd position>that in 3 rd position for the top 3 grain-set spikelets. The individual grain protein content for 3 grain-set spikelets showed 2 nd position >1 st position >3 rd position (Fig. 8,14,18). For 4 or 5 grain-set spikelets,the grain weight in 2 nd position was the highest,followed by that in 1 st,3 rd and the fourth grain (4 th) positions and grain weight in the fifth grain (5 th) position was the smallest,while the individual grain protein content decreased with the increasing of grain positions (Fig. 9,10,15,16,19,20). In conclusion,the variation of the second grain position was a major factor for determining the effects of spikelet and grain positions on grain set and matter accumulation under different conditions. Grain number of each spike depended on the fecundity of basic spikelets,while grain weight,protein content and protein weight depended on the dry matter accumulation in grains of top spikelets. For different wheat cultivars with similar ear length but different grain number and protein content,the cultivars with more grain number showed more sensitivity to nitrogen application level. Interaction of genotype and nitrogen application determined the variation of grain number and matter accumulation on the wheat spike.
出处
《作物学报》
CAS
CSCD
北大核心
2005年第4期431-437,共7页
Acta Agronomica Sinica
基金
国家自然科学基金重点项目 (3 0 0 3 0 0 90 )
江苏省高技术项目 (BG2 0 0 43 2 0 )资助
关键词
小麦
小穗位
粒位
粒重
蛋白质含量
空间分布
Wheat
Spikelet position
Grain position
Grain weight
Protein content
Spatial distribution
