Abstract:

【Objective】To investigate the effects of dry sowing and wet emergence on water and salt distribution, nutrients and cotton yield in different salinized soils.【Methods】Three cotton fields with light, moderate and severe salinity degrees were selected to dynamically monitor the water and salt changes in different locations of the seed holes, wide rows and membranes within 30 days of the seedling emergence water drips, and the cotton growth indexes, indicators of soil nutrients, salinity, pH content, etc., and the yields were analyzed during the critical period of growth and development.【Results】The overall trend of soil volumetric water content, seed hole soil conductivity and soil salinity was: heavy > medium > light cotton field, 0-20 cm soil layer of light, medium and heavy cotton field soil salinity between the membrane was generally greater than the seed holes and the wide rows; light and medium cotton field soil quick-acting nutrient content of 0-20 cm > 20-40 cm, soil alkaline dissolved nitrogen and quick-acting potassium content of the seed holes of the heavy cotton field showed an opposite trend; The soil pH of heavy cotton fields was basically below 8, and light cotton fields were above 8; the highest seedling emergence rate of light cotton fields was 83.4%, which increased by 4.51%, 5.44% and 6.59% compared with light (conventional), medium and heavy cotton fields respectively; the highest seed cotton yield of medium cotton fields was 513.5 kg/667m², which increased by 0.51%, 37.0% and 15.0% compared with light, light (conventional) and heavy cotton fields respectively.【Conclusion】There is no obvious difference in cotton field emergence rates of different saline-alkali levels, but the high moisture content of soil volume is not conducive to cotton emergence. The moderate cotton field seed yield is the highest. The soil salt below 4 g/kg has little impact on seed germination and cotton seedling growth, but the salt content above 6g/kg will affect the yield of seed cotton.

Key words: dry sowing and wet emergence; different salinized soils; water-salt distribution; soil nutrients; yield

摘要：

【目的】探究“干播湿出”对不同盐碱化土壤水盐分布、养分及棉花产量的影响。【方法】选择轻度、中度、重度3种不同盐碱程度的棉田,在滴出苗水30 d内动态监测种孔、宽行和膜间不同位置水盐变化,在生长发育关键时期分析对棉花生长指标、土壤养分、盐分、pH值含量等指标及产量变化。【结果】土壤体积含水率、种孔土壤电导率及土壤含盐量整体趋势为重度>中度>轻度棉田,0~20 cm土层轻度、中度和重度棉田膜间土壤含盐量总体大于种孔与宽行;轻度和中度棉田土壤速效养分含量0~20 cm>20~40 cm,重度棉田种孔土壤碱解氮和速效钾含量呈相反趋势;重度棉田土壤pH值基本处于8以下,轻度棉田在8以上;轻度棉田出苗率最高为83.4%,较轻度(常规)、中度及重度棉田分别增加4.51%、5.44%和6.59%;籽棉产量中度棉田最高为513.5 kg/667m²,较轻度、轻度(常规)及重度棉田分别提高了0.51%、37.0%和15.0%。【结论】不同盐碱程度棉田出苗率差别不明显,但土壤体积含水率过高不利于棉花出苗,中度棉田籽棉产量最高,土壤盐分在4 g/kg以下对种子萌发和棉苗生长影响不大,但含盐量超过6 g/kg以上会影响籽棉产量。

关键词: 干播湿出, 不同盐碱土壤, 水盐分布, 土壤养分, 产量