不同基本苗对早稻分蘖和产量形成的影响

以两系杂交早稻陵两优211与常规早稻品种湘早籼6号为材料,比较不同基本苗数对早稻农艺性状及产量构成因素的差异。结果表明:(1)基本苗6~8苗/穴时,每穴茎蘖数明显多于1~4苗/穴处理,且能更早达到分蘖高峰。(2)分蘖期叶面积指数与基本苗数呈正相关,而在乳熟期叶面积指数、叶片SPAD值与基本苗数均呈负相关。(3)成熟期地下部分和地上部分干物质量随基本苗数增加表现为先增加后降低的趋势,地上部分干物质量均以移栽苗数4苗/穴最高,杂交早稻地下部分干物质量以移栽苗数4苗/穴最高。(4)产量随基本苗数增加而增加,有效穗数变化趋势与产量一致,每穗总粒数、实粒数和结实率与产量变化趋势相反,但每穗实粒数、结实率和千粒重各移栽苗数处理间差异不明显,受品种遗传特性的影响可能较大。(5)随着移栽苗数的增加,杂交早稻产量的最大增长幅度没有常规早稻的大,有效穗数也呈现相同趋势。试验结果表明每穴插3~5苗是获得早稻高产稳产的重要措施。

Influence of Different Basic Seedling Number on Tillering Dynamics and Yield Formation in Early Rice

Two-line hybrid early rice Lingliangyou 211 and conventional early rice variety Xiangzaoxian 6 were used as materials to compare the differences of agronomic traits and yield components between different basic seedlings and different rice varieties.The results showed that:(1) When the basic seedlings were 6-8 seedlings/hole,the number of tillers per hole was obviously more than that of 1-4 seedlings/hole treatment,and the tiller peak could be reached earlier,the tiller peak of transplanted seedlings with 1-4 seedlings/hole treatment was relatively late and not obvious.Leaf area index at tillering stage was positively correlated with the number of basic seedlings,while at milky stage,leaf area index and SPAD value were negatively correlated with the number of basic seedlings.The highest number of transplanted seedlings was 1 seedling/hole treatment.At maturity stage,the dry matter weight of underground and aboveground parts increased first and then decreased with the increase of basic seedlings.The highest dry matter weight of aboveground parts was 4 seedlings per hole,and the dry matter weight of underground of hybrid early rice was 4 seedlings per hole.Yield increased with the increase of basic seedlings,and the change trend of effective panicle number was consistent with yield.The change trend of total grain number per panicle,grain number and seed setting rate was opposite to that of yield.However,there was no significant difference in the number of seedlings per panicle,seed setting rate and 1000-grain weight among the treatments,which might be affected by the genetic characteristics of the varieties.With the increase of transplanted seedlings,the maximum yield increase of hybrid early rice was not as large as that of conventional early rice,and the number of effective panicles showed the same trend.The results showed that planting 3-5 seedlings per hole was an important measure to obtain high and stable yield of early rice.