两个高产海岛棉品种(系)产量形成期同化物积累分配特点的研究

目的]研究两个主载海岛棉(Gossypium barbadense L.)品种(系)新海21号的提高系-优系193(YX-193)和新海28号(原代号TH-45)(XH-28)产量形成期的生长发育、各器官同化物积累分配及其与LAI、LAD、叶片SPAD值的相关性.方法]通过覆膜滴灌,观测了海岛棉系-优系193和新海28号的生长发育和同化物积累分配等指标,利用SPAD-502叶绿素仪测定SPAD值,采用相关分析和回归分析等统计方法进行分析.结果]除了株高外,系-优系193的茎粗、叶面积指数、光合势、叶面积比率、比叶面积、相对生长率、净同化率、最大LAI、同化物累积略高于新海28号,同化物积累速率最快均在出苗后60～90 d;不同器官同化物分配率规律不同,其共同特点是:生殖器官>营养器官>根;同化物积累量与叶片SPAD值呈线性相关,与LAI、LAD符合二次回归模型.结论]在相同条件下,产量形成期海岛棉品种(系)系-优系193的同化物累积高于新海28号;营养器官同化物累积均呈抛物线型,生殖器官和单株总同化物积累均接近"S"型.两品种(系)的营养器官/总干重、叶干重比和根冠比均呈下降趋势,生殖器官/总干重均呈递增趋势.

Research of Characteristics of Assimilates Accumulation and Distribution of Two High-yield Sea Island Cotton(Gossypium barbadense L.)Varieties (lines) During Yield Formative Period

【Objective】The growth and development,assimilates accumulation and distribution of organs and its correlation with LAI,LAD and leaf SPAD value of YX-193 and XH-28 during output formative period were studied.Both of them were the improved lines of two major cultivated sea island cotton (Gossypium barbadense L.)varieties Xinhai 21-Priority system 193,and Xinhai 28(formerly-code-named TH 45).【Method】Indexes such as the growth and development,assimilates accumulation and distribution of Sea Island cotton YX-193 and XH-28 were observed by mulched drip irrigation,using SPAD-502 chlorophyll meter the SPAD values were measured,correlation analysis and regression analysis were used to analyze data.【Result】The results showed that stem diameter,leaf area index,photosynthetic potential,leaf area ratio,specific leaf area,relative growth rate,net assimilation rate,maximum LAI,and assimilates accumulation of YX-193 are slightly higher than that of XH28 except plant height,the most rapid rate of assimilates accumulation is in between 60～90 d after seedling emergence;rules of assimilates distribution rate of different organs are different,their common characteristics are genital organs>vegetative organs>root;assimilates accumulation showed linear correlation with the leaf SPAD value,and meet the quadratic regression model with LAI,LAD.【Conclusion】Under the same conditions,the assimilates accumulation of YX-193 are higher than XH28's during yield formative period;assimilates accumulation of vegetative organs showed a parabolic type,assimilates accumulation of reproductive organs and single plant are close to "S" type.The vegetative organs / total dry weight,leaf dry weight ratio and root to shoot ratio of the two varieties(lines) showed decreasing trend,genital organs / total dry weight showed an increasing trend.