不同浓度盐胁迫对直播水稻农艺及产量性状的影响

Effects of Different Concentrations of Salt Stress on Agronomy and Yield Traits of Direct Seeding Rice

以富源4号为供试材料,通过盆栽试验探究盐胁迫对水稻直播栽培植株生长发育及产量的影响。结果表明,随着盐胁迫程度的增加,水稻出苗率、成苗率、单株分蘖率、成穗率、叶面积、生物量、株高、收获指数及产量均呈现不同程度下降趋势,且生育期延迟。其中:含盐量≥1.23‰的处理与CK穗数间有极显著差异;含盐量≥1.36‰时,与CK在出苗率、单株分蘖率、单株成穗率、生育期间均有极显著差异;含盐量≥1.92‰的处理与CK在地上部生物量、产量间有显著差异;含盐量≥3.10‰的处理与CK在成苗率、叶面积、株高、收获指数、穗粒数、千粒重、结实率间有显著差异;含盐量≥4.95‰时,水稻基本无产量。在产量构成因素中,穗数对盐胁迫极敏感,是减产的主导因素;而穗粒数、结实率和千粒重对盐胁迫较敏感,是次要因素,对盐胁迫的响应程度近似。这些指标可作为宁夏盐碱地水稻直播种植和土壤改良利用的重要参考指标。

The effects of salt stress on the growth and yield of rice under direct seeding cultivation were studied by pot experiment using Fuyuan No.4 as experimental material.The results showed that with the increase of salt stress degree,the seedling emergence rate,survival rate,tillering rate per plant,heading rate,leaf area,biomass,plant height,harvest index and yield of rice showed a decreasing trend in different degrees,and the growth period was delayed.When salt content≥1.23‰,there was a significant difference in ear number compared with CK.When salt content was greater than 1.36‰,there were significant differences in seedling emergence rate,tillering rate per plant,heading rate per plant and growth period compared with CK.When the salt content was more than 1.92‰,there were significant differences in above-ground biomass and yield in comparison with CK.When salt content≥3.10‰,there were significant differences in seedling formation rate,leaf area,plant height,harvest index,grain number per panicle,1000-grain weight and seed setting rate in comparison with CK.When the salt content was more than 4.95‰,there was basically no rice yield.Among the yield composition factors,panicle number was very sensitive to salt stress and was the leading factor of yield reduction;the number of grains per panicle,seed setting rate and 1000-grain weight were relatively more sensitive to salt stress,wasthe secondary factors,and were similar in the response degrees to salt stress.These indexes can be used as important reference indexes for direct rice planting and soil improvement and utilization in Ningxia saline-alkali land.