播期对不同穗部特征小麦品种(系)生育期和农艺性状的影响

为了解播期对多小穗和寡小穗小麦生育期及农艺性状的影响,对13份不同来源的小麦品种(系)两年分期播种的生育期和6个农艺性状(株高、单株有效分蘖数、穗长、每穗小穗数、穗粒数和千粒重)进行了分析和评价。结果表明,播期的推迟导致材料间出苗期差异变大,抽穗期差异缩小,但开花期和成熟期差异变化不大,各农艺性状值减小。经方差分析,各农艺性状在不同播期和品种(系)间均存在极显著差异,其中单株有效分蘖数的变异系数最大,穗粒数次之,每穗小穗数最小。多小穗材料10-A和寡小穗材料BE89的穗长、每穗小穗数和穗粒数在播期间差异较小。经相关分析,播种至出苗和分蘖至抽穗天数与温度呈极显著负相关,出苗至分蘖和开花至成熟天数与平均日照时间呈显著负相关,抽穗至开花天数与温度和降水量呈显著负相关。经多元逐步回归分析,日最高温和日均温对多小穗和寡小穗材料的分蘖至抽穗天数有显著影响,平均日照时间在开花期、日最高温在成熟期分别对多小穗材料发育有显著影响。由此可见,小穗数特异性材料的每穗小穗数在不同播期下能保持稳定。

Effect of Different Sowing Dates on Growth Stage and Agronomic Traits of Wheat Varieties (Lines) with Different Spike Characteristics

To understand the influence of sowing dates on the multi-spikelet and few-spikelet wheat varieties,the growth stages and six agronomic traits(plant height,number of fertile tillers,spike length,spikelet number per spike,kernel number per spike and 1 000-grain weight) of 13 different wheat varieties(lines) were evaluated in two years. The results showed that the late sowing could cause wide variations of seedling stage but the narrow difference of heading stage,and it had little effect on the difference of flowering stage and mature stage.The value of agronomic traits were decreased under the treatment of late sowing dates. ANOVA analysis results showed that there was significant difference of agronomic traits among all materials treated with different sowing dates.Number of fertile tillers per plant showed the biggest coefficient of variance between the sowing dates,followed by kernel number per spike and spikelet number per spike. The small differences of spike length,spikelet number per spike,and kernel number per spike were observed between multi-spikelet line 10-A and few-spikelet line BE89 treated with different sowing dates. Simple correlation showed that spike length was positive significantly correlated with spikelet number per spike and 1 000-grain weight,while spikelet number per spike was positive significantly correlated with kernel number per spike. This illustrates that increasing spikelet number per spike could improve kernel number per spike.The days from sowing to seedling emergence and tillering to heading were negative significantly correlated with the temperature,and the days of seedling emergence to tillering and flowering to maturing were negative significantly correlated with the average duration of sunshine,and the days from heading to flowering was negative significantly correlated with temperature and amount of precipitation. Multiple stepwise regression analysis showed that the daily maximum temperature and daily mean temperature significantly affected the days from the tillering to the heading of the multi-spikelet and few-spikelet lines. The average sunshine time at the flowering stage,and the daily maximum temperature at the mature stage significantly affected multi-spikelet line. Thus,spikelet number per spike of materials with specific spikelet number can remain stable under different sowing dates.