施氮量对3个极早熟高粱品种干物质积累及籽粒品质的影响

Effects of Nitrogen Application Rate on Dry Matter Accumulation and Grain Quality of Three Extremely Early Maturing Sorghum Varieties

为探明不同用量氮素对春播早熟区极早熟高粱的干物质积累、氮素积累及籽粒品质的影响,本试验采用裂区设计,以氮素施用量为主处理,以龙杂19、龙杂20和齐杂722品种为副处理,设置0(N0)、60(N60)、120(N120)、180(N180)、240(N240)、300(N300)kg/hm^(2)共6个施氮水平,研究不同施氮量对不同品种高粱植株干物质积累、氮素积累和籽粒淀粉、单宁及氮、磷、钾含量的影响。结果表明,施用氮肥可有效提高3个品种高粱干物质和氮素积累量,不同生育时期达到较高干物质积累量的施氮量分别为五叶期120~240 kg/hm^(2)、拔节期120~180 kg/hm^(2)、开花期120~240 kg/hm^(2)、成熟期300 kg/hm^(2);各阶段干物质积累量表现为开花期-成熟期>拔节期-开花期>五叶期-拔节期>出苗期-五叶期。同时,不同生育时期达到较高氮素积累量的施氮量分别为五叶期120~240 kg/hm^(2)、拔节期180 kg/hm^(2)、开花期和成熟期240 kg/hm^(2);各阶段氮素积累量表现为拔节期-开花期>开花期-成熟期>五叶期-拔节期>出苗期-五叶期。籽粒淀粉和单宁含量随施氮量增加呈降低趋势,其中,施氮处理后的单宁含量显著低于不施氮处理。施氮肥后籽粒氮含量显著增加,但磷钾含量无显著变化。

In order to explore the effects of different nitrogen rates on dry matter accumulation,nitrogen accumulation and grain quality of extremely early maturing sorghum in spring sorghum area,the varieties of Longza 19,Longza 20 and Qiza 722 were used as experimental materials,and split plot design was adopted for the experiment.Six nitrogen rates,including 0(N0),60 kg/hm^(2)(N60),120 kg/hm^(2)(N120),180 kg/hm^(2)(N180),240 kg/hm^(2)(N240)and 300 kg/hm^(2)(N300)were set to study their effects on dry matter and ni-trogen accumulation of plants,as well as starch,tannin,nitrogen,phosphorus and potassium contents in grains of different varieties.The results indicated that the application of nitrogen fertilizer could effectively increase the accumulation of dry matter and nitrogen.The nitrogen rates for higher dry matter accumulation at different growth stages were 120~240 kg/hm^(2)at five-leaf stage,120~180 kg/hm^(2)at jointing stage,120~240 kg/hm^(2)at flowering stage,and 300 kg/hm^(2)at mature stage.The change law of dry matter accumulation was as from flowering stage to mature stage>from jointing stage to flowering stage>from five-leaf stage to jointing stage>from seedling stage to five-leaf stage.At the same time,the nitrogen rate for higher nitrogen accumulation was 120~240 kg/hm^(2)at five-1eaf stage,180 kg/hm^(2)at jointing stage and 240 kg/hm^(2)at flowering and mature stages.The change law of nitrogen accumulation was as from jointing stage to flowering stage>from flowering stage to mature stage>from five-leaf stage to jointing stage>from seedling stage to five-leaf stage.The starch and tannin contents in the grains decreased with the increase of nitrogen rate,and the tannin content was significantly lower under nitrogen fertilizer application compared with no nitrogen fertilizer application.The nitrogen content in grains significantly increased after nitrogen fertilizer application,while the phosphorus and potassium contents did not change significantly.