品种和播期对麦套短季棉产量和纤维品质空间分布的影响

Effects of cultivar and sowing date on spatial distribution of yield and fiber quality in intercropping system of wheat and short-season cotton

【目的】研究不同短季棉品种与播期对棉花产量和纤维品质空间分布的影响,为黄河流域棉区麦棉两熟全程机械化适宜播期及品种的选择提供参考。【方法】于2019―2020年开展大田试验,采用裂区设计,以短季棉品种(锦科707和鲁棉2387)为主区,4个播期5月10日(SD1)、5月20日(SD2)、5月30日(SD3)、6月10日(SD4)为副区。调查棉花生物量、株式图、产量和产量构成要素等指标并测定主要纤维品质指标及纤维品质综合指标Q值。【结果】晚播(SD4)处理下棉花花铃期延长,而叶面积指数、果枝数和果节数均随着播期的推迟呈现逐渐降低的趋势。播期显著影响皮棉产量和棉铃分布,2019年和2020年SD1、SD2和SD3皮棉产量均无显著差异,但播期推迟至6月10日的SD4处理下2年2个品种平均皮棉产量较SD1、SD2和SD3分别降低38.7%、37.2%和32.7%。此外,随播期推迟,第1~3果枝的结铃数占比显著增加,第6果枝以上的结铃数占比显著减少。对比纤维品质综合指标Q值,SD1、SD2、SD3处理的中部和上部果枝棉铃的纤维品质优于SD4。2个品种在产量和品质上存在显著差异,2年均是鲁棉2387皮棉产量较高,锦科707的纤维品质较优。【结论】2个品种表现相似,在SD1、SD2、SD3播期下皮棉产量无显著差异且形成相对较优的纤维品质。因此,为避免产量大幅降低,黄河流域棉区麦套短季棉模式下棉花播种日期不应晚于5月30日。

[Objective]This study aims to investigate the effects of different short-season cotton cultivars and sowing dates on the spatial distribution of cotton yield and fiber quality,and to provide a reference for the selection of suitable sowing date and cultivar for the application of mechanized wheat-cotton intercropping system in the Yellow River basin cotton production region.[Method]A two years'field experiment was conducted using split zone design in 2019-2020,two short-season cotton cultivars(JX 707 and LM 2387)were taken as the main plot,and the four sowing dates were set as the sub-plot,including May 10th(SD1),May 20th(SD2),May 30th(SD3),June 10th(SD4).The cotton biomass,plant architecture,lint yield and yield components were investigated,and the main fiber quality index and comprehensive index of fiber quality Q score were measured.[Result]Late sowing date(SD4 treatment)showed prolonged flowering and boll development period of cotton,while leaf area index,number of fruit branches and number of fruit nodes decreased with the delayed sowing date.The sowing dates significantly affected the lint yield and boll distribution.There were no significant differences among lint yield of SD1,SD2,and SD3 in both experimental years.However,when the sowing dates was postponed to June 10th(SD4),the average lint yield of two cultivars in two years was reduced by 38.7%,37.2%,32.7%compared with SD1,SD2,and SD3,respectively.In addition,when the sowing dates was delayed,the proportion of bolls from the first to third fruit branches increased significantly and the proportion of bolls formed above the sixth fruit branch decreased significantly.Comparing the comprehensive index of fiber quality,Q score,the quality of the fibers from middle and upper branches of SD1,SD2,and SD3 were better than that of the late sowing treatment(SD4).There were significant differences between two cultivars in terms of yield and fiber quality.Specifically,the cotton lint yield was higher in LM 2387,and the fiber quality was better in JX 707 in both years.[Conclusion]In summary,for both cotton varieties,the sowing date in May(SD1,SD2,and SD3)showed no significant effect on lint yield,and with relatively better fiber quality.In order to avoid a significant reduction in yield,the cotton sowing date of the intercropping system of wheat and short-season cotton in the Yellow River basin cotton production region should not be later than May 30th.