木薯光合作用特性研究

 以木薯为研究对象,测定其净光合速率(net photosynthesis,Pn)及相关因子变化,通过测定叶片叶绿素含量,调查单株产量以及主要性状,研究多变量之间的关系.结果表明,华南8号(SC₈)没有明显的"午休"现象,而华南5号(SC₅)、华南205(SC₂O₅)有明显的"午休"现象,三者的Pn分别与外界光强、大气CO₂浓度呈现极显著正相关和极显著负相关;经成组t测验分析,SC₈ Pn的日变化与SC₅,SC₂O₅ Pn的差异达到极显著.进一步多元分析证明,SC₈单株产量显著高于SC₂O₅,但其主茎高度却显著低于SC₂O₅,同时相关分析发现单株产量与主茎高度呈负相关性(但不显著),与茎粗、叶片叶绿素含量分别具有极显著和显著的正相关关系.可见,高光合速率、优良的株型是木薯块根高产的决定因素.

The study on photosynthetic characteristic of cassava

It was reported that net photosynthesis and its relative factors' change for cassava with portable photosynthetic system.The chlorophyll content,per plant yield and some major agronomic characters were measured to analysis the relationship among them.It showed that South China eight(SC8) variety hasn't noon break phenomenon in midday,while the South China 205(SC205) and South China 5(SC5) does.Next,there is remarkable positive correlation between Pn and the light intensity,but the remarkably negative correlation was occurred between Pn and ambient carbon dioxide concentration for these cassva varieties in a whole day.The pair group t-test for the cassava Pn was showed most remarkably difference between SC8 and SC205,SC5 respectively.The further multivariable anova analysis was used to indicated the per plant yield of SC8 was much higher yield than SC5 and SC205,but the stem height much lowe than it.As while,the negative correlation was discovered between per plant yield and stem height(not remarkably),but there were most remarkably and remarkably positive correlation both stem diameter and chlorophyll content respectively.Therefore,the powerful Pn and the fine type of plant were determinated factors for high root yields of cassava.