鲁棉研36号密植留叶枝效应研究

Study on Effect of High Planting Density and Vegetative Branch Retention of SCRC 36

研究了适当密植留叶枝对鲁棉研36号生育进程、皮棉产量及纤维品质等的影响。结果表明,同密度留叶枝较去叶枝处理开花期推迟1～2 d,对吐絮期影响不大。随着密度增加,株高、果枝数、叶枝数均呈降低趋势;不同密度留叶枝处理平均单株有叶枝1.8～2.6个,株高较去叶枝矮1～2 cm。铃重随密度增加呈下降趋势,但留叶枝对铃重影响不明显。不同密度留叶枝处理皮棉和霜前皮棉产量均低于同密度去叶枝处理,减产幅度1.7%～8.1%;每公顷7.5万株(A2)和9.0万株(A3)无论去、留叶枝产量水平都较高,且留叶枝较去叶枝处理减产幅度较小;叶枝对产量的贡献率为3.8%～16.4%,密度越大贡献率越小。密植留叶枝对纤维品质无明显不利影响。本研究结果说明鲁棉研36号对密度的适应范围较宽,易管理,推行每公顷7.5万株至9.0万株留叶枝简化栽培、减少管理用工完全可行。

During 2016 and 2017, a random block design experiment was conducted in Linqing of Shan- dong Province to explore the effects of appropriate planting density and vegetative branch xretention on growth process, lint yield and fiber quality of SCRC 36. The resuhs showed that the flowering time was 1 - 2 - day delayed under vegetative branch retention, but it had little effect on the boll opening time. With the increase of planting density, the plant height, the number of fruit branches, the number of vegetative branches and boll weight showed decreasing trends. The average number of vegetative branches per plant was 1.8 - 2.6, and the height of plants with vegetative branches retention was 1 -2 em lower. Under vegetative branches retention, the boll weight was similar, but the total lint yield and pie- frost lint yield was 1.7% ~ 8.1% lower. The yield was both higher at 75 000 （A2） and 90 000 plants per hectare, while the yield 1eduction was lower un- der vegetative branch retention. The contribution rate of vegetative branches to total lint yield was 3.8% - 16. 4% ,which decreased gradually with the increase of density. There was no significant negative effect on the fiber quality under high planting density and vegetative branch retention. All the results indicated that SCRC 36 had wide adaptability to density. With the density at 75 000 and 90 000 plants per hectare under vegetative branch l〉tention, it is practicable to simplify the management and reduce the work force for SCRC 36.