带旋和全旋耕作对稻茬小麦生长和土壤理化性质的影响

    Effects of the strip rotary and full rotary tillage on the wheat growth and soil physicochemical properties in rice stubble

    • 摘要: 为明确带旋耕作在稻茬麦区的适用性,该研究于2018-2020年在水稻秸秆切碎匀铺还田条件下,以全旋(full rotary tillage,FRT)耕作为对照,研究了带旋(strip rotary tillage,SRT)耕作对稻茬麦田土壤理化性质、小麦生长和籽粒产量的影响。结果表明,与FRT相比,SRT在土壤偏干状况下大幅提升了0~10 cm土层贮水量,提升幅度为15%~43%,而在土壤偏湿时提升幅度仅为3%~9%。带旋耕作下土壤温度日变化幅度平缓,且在低温条件下有助于提升5和15 cm土层温度。2 a间5~15 cm土层SRT土壤速效氮与速效钾含量较FRT分别增加12%、55%、41%和17%,差异显著(P<0.05),SRT促进了土壤养分在浅层富集。在2019-2020年,SRT较FRT显著增加了幼苗单株次生根数、单株地上部生物量、植株可溶性糖含量和叶片RuBPCase活性(P<0.05),明显提升了幼苗质量,同时2 a间均提高了开花期和乳熟期单茎叶面积、叶片RuBPCase活性以及开花期和成熟期单茎干物质量。2 a间均以SRT产量最高,比FRT分别增产11%和14%,穗粒数比FRT分别增加16%和5%,差异均达显著水平(P<0.05)。综上,带旋耕作下良好的土壤水、热、肥条件有助于幼苗健壮生长,提升了单茎光合生产能力,促进了幼穗发育和穗粒数形成,但带旋耕作出苗率较全旋耕作低了19.3%,未来还需结合其壮苗优势开展农机农艺配套技术研究。

       

      Abstract: Abstract: Sticky texture of soil and tillage condition can be found in the rice-wheat rotation area, due to the conventional management practices of puddling and flooding. The returning rice straw into the field can also seriously affect the emergence and growth of wheat seedlings. The tillage modes can dominate the form and amount of the crop residues returning into the soil, together with the hydrothermal environment in the soil. Therefore, a suitable tillage and seeding mode can facilitate the emergence and growth of seedlings, even for the high grain yield of wheat. Strip rotary tillage (SRT) has been an effective practice to combine no- and convention-tillage. In this study, a systematic investigation was implemented to explore the effects of the SRT on the physical and chemical properties of soil, wheat growth, and grain yield in the rice stubble field from 2018 to 2020. The applicability of SRT was also clarified in the rice-wheat rotation areas. Among them, full rotary tillage (FRT) was taken as the control treatment. Specifically, the rotary tillage was implemented twice (10-15 cm depth), and the straw was evenly mixed into the soil, finally seeding. The used seeder included the functions of shallow rotary tillage, drill seeding, soil covering, excavating drainage ditch, and roller suppression. In SRT, the rice stubble was uniformly covered on the soil surface, and then directly seeded using the strip rotary seeder. The strip tillage depth of the seeder was set to 4 cm. The stubble, soil, and fertilizer on the surface were broken to mix with a 4 cm width of tillage blade. Thus, there was a sowing belt with about 4 cm width and a no-till belt with about 16 cm width in the field. The seeds were evenly sown in the sowing trench, and then a chain net covered the soil and straw on the sowing trench. The results showed that the SRT significantly increased the water storage in the 0-10 cm soil layer by 15%-43% under dry soil conditions, but only increased by 3%-9% under wet soil conditions, compared with the FRT. There was a gentle diurnal variation of soil temperature under SRT. The temperature of the soil layer at 5 and 15 cm increased at low temperatures. The content of available nitrogen and potassium in the 5-15 cm soil layer of SRT increased by 12%, 55%, 41%, and 17%, compared with the FRT, respectively (P<0.05). The enrichment of soil nutrients was promoted in the shallow soil. The SRT significantly improved the number of secondary roots per plant, aboveground biomass per plant, plant soluble sugar content, and RuBPCase activity in the leaves (P<0.05) in 2019-2020, compared with the FRT, indicating the better quality of seedlings. At the same time, the SRT improved the leaf area per stem, and the RuBPCase activity in the leaves at the anthesis and milk ripening in the two seasons. The highest yield of SRT was achieved, which increased by 11% and 14%, compared with the FRT. The number of grains per panicle also increased by 16% and 5%, respectively, with significant differences (P<0.05). In conclusion, the favorable soil conditions in water, heat, and nutrient under SRT were conducive to the vigor growth of seedlings, the improved photosynthetic production of a single stem, the development of young spike, and the formation of grain number per spike. Furthermore, the low emergence rate of seedlings under SRT can be expected to investigate using the supporting agronomic techniques for the vigorous seedlings.

       

    /

    返回文章
    返回