不同氮效率玉米品种籽粒灌浆特性研究

Research on Grain Filling Characteristics of Different Nitrogen Efficiency Genotypes of Maize

为明确不同氮效率玉米品种籽粒灌浆特性的差异,从而有针对性地指导合理施用氮肥,在大田试验条件下,选用屯玉99(高氮高效型)、潞玉19(低氮高效型)和先玉335(双高效型)3个不同氮效率玉米品种为供试材料,设置0(N0)、80(N1)、160(N2)、240(N3)kg/hm24个不同施氮水平,测定授粉后玉米不同部位籽粒的干、鲜质量,采用回归分析方法研究授粉后时间(d)与籽粒干质量、含水率及灌浆速率之间的关系。结果表明,4个施氮水平下,不同玉米品种不同部位籽粒干质量增长速率峰值拐点出现的时间不同,屯玉99、潞玉19、先玉335分别在N3、N1、N2处理下拐点出现时间最早,且屯玉99拐点出现的最早时间早于潞玉19、先玉335,干物质积累增速最快。屯玉99和先玉335分别在N3、N2处理下籽粒含水率下降最快,而潞玉19在N1处理下籽粒含水率下降最迅速。屯玉99和潞玉19籽粒灌浆速率峰值出现时间集中在授粉后25~30 d,而先玉335籽粒灌浆速率峰值集中在授粉后20~25 d。顶部籽粒和中下部籽粒的干质量、含水率和灌浆速率均存在差异,而不同氮效率玉米籽粒干质量和灌浆速率的最佳施氮水平与产量最高的施氮水平保持一致。3个玉米品种产量形成都与其氮效率特性密切相关。

In order to guide the application of nitrogen fertilizer, the difference of grain filling characteris-tics of different nitrogen efficiency genotypes of maize was explored. Under field experiment condition, Tu- nyu 99 , Luyu 19 and Xianyu 335 were used as the test materials, four application levels of nitrogen were designed , which were 0 （ NO） ,80（N1） ,160（ N2） , 240 （ N3 ） kg/ha, the maize grain dry weight and fresh weight after pollination were measured, the relationship of time after pollination t ime, grain dry weight, moisture content and filling rate were discussed using regression analysis. The results showed that the dry kernels quality growth rate peak inflection point of different parts of different varieties appeared at differ-ent time,Tunyu 99,Luyu 19 and Xianyu 335 gained inflection point appeared most early in N3 ,Nland N2 treatment , and Tunyu 99 grain inflection point appeared most earlycompared with Luyu 19 and Xianyu 33 , the increase of dry matter accumulation of Tunyu 99 was the most quickly. The grain moisture content of Tunyu 99 and Xianyu 335 decreased most quickly under N3 ,N2 treatment, respectively, the moisture con-tent of Luyu 19 decreased most rapidly under N1 treatment. The peak value of grain filling rate of Tunyu 99 and Luyu 19 appeared on 25-30 d after pollination, which of Xianyu 335 appeared on 20-25 d after pollination. The top and middle lower grain were different in dry weight, water content and grain filling rate , but the optimal nitrogen application rate of grain dry weight and grain filling rate of three maize vari-eties was consistent with the nitrogen application of the highest yield. The final yields of three maize varie-ties were closely related to the characteristics of nitrogen efficiency.