休闲期耕作对旱地小麦产量及品质的影响

Effects of tillage during fallow period on grain yield and quality of dryland wheat

[目的]探究休闲期耕作对旱地小麦土壤水分、根系、产量及品质的影响,明确最佳的休闲期耕作方式。[方法]以晋麦92为供试材料,设休闲期深松(深度30～40 cm)和深翻(深度25～30 cm)2个处理,于2015—2016年在山西省闻喜县开展大田试验。[结果]与深翻处理相比,深松显著提高播种期—孕穗期0～300 cm土壤蓄水量;显著提高越冬—孕穗期0～80 cm土层根系总长、总体积,0～20 cm土层根系活力;显著提高花后旗叶和籽粒GS活性;显著提高籽粒蛋白质含量、湿面筋含量、干面筋含量、沉降值;显著提高籽粒产量,增幅达9.43%,穗数显著增加是产量提高的主要原因;显著提高水分利用效率,达4.41%。将土壤蓄水量、根系特征与籽粒产量、蛋白质含量进行逐步归回分析得出:孕穗期、开花期土壤蓄水量分别与籽粒产量、蛋白质含量关系紧密,关键生育时期根系特征与籽粒产量及蛋白质含量关系紧密。[结论]休闲期深松处理较深翻蓄积土壤水分,促进小麦根系下扎,提高根系活力,提高花后旗叶和籽粒GS酶活,从而提高旱地小麦的产量和品质。

[Objective]The study was conducted in order to determine the effect of different fallow tillage practices on the soil wa ter storage, root characteristics, grain yield, and quality, and clarify the best tillage technology for fallow period. [Methods] A field trial was conducted with two different tillage methods, either subsoiling （30～40 cm） or deep tillage （25～30 cm）, and win ter wheat eultivar, Jinmai 92, was selected as testing material and planted from 2015 to 2016 in Wenxi, Shanxi province. [Results] The results showed that subsoiling tillage significantly improved the soil water storage capacity at the depth of 0 300 cm from sowing stage to booting storage compared to that of the deep tillage, and the root length and total volume at 0～80cm soil layer and root activity at 0～20cm soil layer from wintering stage to booting stage were also greater in subsoiling treatment than that of the deep tillage. The activities of GS in flag leaves and grains were also significantly higher than that of the deep tillage. The contents of grain protein and its constitution, sedimentation value, wet gluten content, and dry gluten content were sta tistieally enhanced than in subsoiling treatment. A higher spike number, grain number per spike, and grain yield were observed in subsoiling treatment, and significant difference of the spike number was detected between two treatments. Therefore, the subsoiling tillage during fallow period was benefit to grain yield. Stepwise regression analysis indicated that the soil water storage at booting and anthesis stages was respectively related to grain yield and protein content, and root characteristics during key growth stages was closely related to grain yield and protein content. [Conclusion] Sub soiling during fallow period can store soil moisture, promote the growth of the root and increase root activity, improve grain yield and quality of dryland wheat.