休闲期不同耕作模式对旱地麦田土壤水分、养分及产量的影响

为探索适宜晋南旱地小麦高效生产的耕作模式,以晋麦92为试验材料,设置休闲期深翻/深翻、深松/深翻、深松/深松、常规耕作(对照)4个耕作模式,研究其对土壤水分及养分、作物生长和水分利用效率的影响。结果表明,深翻/深翻、深松/深翻、深松/深松模式较对照休闲末期3m内土壤蓄水量和土壤蓄水效率显著提高,土壤蓄水效率提高达52.5%~91.3%,以深松/深松模式较好;越冬-孕穗期3m内土壤蓄水量提高,且深松/深松模式与对照差异显著;各生育时期单株干物质积累量提高,且越冬-拔节期深松/深松、深松/深翻模式与对照差异显著,孕穗-成熟期各耕作模式与对照差异均显著;穗数、千粒重、产量和水分利用效率显著提高,其中穗数提高22.7%~29.9%,水分利用效率提高15.1%~21.6%,产量提高39.4%~60.3%,以深松/深松模式较好;收获后0~40cm土层土壤有机质平均含量提高2.5%~8.7%,速效磷含量提高11.1%~34.4%,碱解氮含量提高5.1%~20.2%,以深松/深松模式较好。总之,深翻/深翻、深松/深翻、深松/深松模式均能提高土壤蓄水保墒能力,改善养分供应状况,有利于促进小麦干物质积累,最终提高产量和水分利用效率,以深松/深松模式最佳。

Effect of Different Tillage Systems during Fallow Period on Soil Water,Nutrient Content and Wheat Yield in Dryland

In order to explore the suitable tillage systems in dryland for high efficiency wheat production in Jinnan,four systems,including DT/DT (2-year continuous deep plowing during fallow period),ST/DT (2-year rotational subsoiling and deep plowing during fallow period),ST/ST (2-year continuous subsoiling during fallow period) and CK (2-year continuous conventional tillage system during fallow period) were applied.The study was conducted with Jinmai 92 to determine the effect of different tillage systems on soil water storage and nutrient content,crop growth and water use efficiency.The results showed that compared with CK,DT/DT,ST/DT and ST/ST significantly increased soil water storage in the 0-3 m depth after fallow period and soil water storage efficiency.And soil water storage efficiency was increased by 52.5% to 91.3%.The effect of ST/ST on water storage was better.Compared with CK,DT/DT,ST/DT and ST/ST increased soil water storage in the 0-3 m depth from over-wintering stage to booting stage,on which the effect of ST/ST was significant.Compared with CK,DT/DT,ST/DT and ST/ST increased dry weight per plant at different growth stages.Compared ST/ST and ST/DT with CK from over-wintering stage to elongation stage,the effect was significant.And the effect of different tillage systems was significant at booting and maturing stages.Compared with CK,DT/DT,ST/DT and ST/ST significantly increased spike number,1 000-grain weight,yield and water use efficiency.Spike number,water use efficiency and yield were increased by 22.7% to 29.9%,15.1% to 21.6%,and 39.4% to 60.3%,respectively,on which the effects of ST/ST were better.Compared with CK,DT/DT,ST/DT and ST/ST improved soil average nutrient content in 0-40 cm depth after harvest.Organic matter content,available phosphorus content and alkali-hydrolyzable nitrogen content were improved by 2.5% to 8.7%,11.1% to 34.4%,and 5.1% to 20.2%,respectively,on which the effect of ST/ST was better.In conclusion,DT/DT,ST/DT and ST/ST could improve soil water storage capacity and soil nutrient supply status,and promote the accumulation of wheat matter,which was favorable for improving grain yield and water use efficiency.The ST/ST system was optimal.