Keywords: 
• 玉米 /
• 叶绿素质量分数 /
• 光合性状 /
• 相关性 /
• QTL分析

Abstract: In order to explore the correlation and genetic mechanism of maize photosynthetic traits ,two F2 populations (Y and R) with different genetic backgrounds were used to identify correlation and QTLs for 10 photosynthetic traits ,which included chlorophyll‐a content ,chlorophyll‐b content ,total chlorophyll content ,net photosynthetic rate ,stomata conductance ,intercellular CO2 concentration ,transpiration rate and some others .The correlation between two of chlorophyll‐a content ,chlorophyll‐b content and total chlorophyll content in different periods was non‐significant in population Y ,and was highly significant in population R .The correlation between other traits of the two populations was highly consistent .In the same growth period of the plants ,total chlorophyll content was in highly significant correlation with chlo‐rophyll‐a content and chlorophyll‐b content ,highly significant correlation was also detected between net photosynthetic rate and stomata conductance ,between net photosynthetic rate and transpiration rate ,and between stomata conductance and transpiration rate ,stomata conductance was moderately correlated with intercellular CO2 concentration ,and chlorophyll content was weakly correlated with net photosynthetic rate ,stomata conductance ,intercellular CO2 concentration and transpiration rate .In population Y ,1 QTL was detected for chlorophyll‐a content (FCa) ,chlorophyll‐b content (FCb) and total chlorophyll content (FCt) each ,at the five‐leaf stage .All these QTLs were located in umc2391‐mmc0371 on chromosome 4 and each explained 8.65% to 9.87% of the phenotypic variance .And other three QTLs were detected at the milk stage ,one for chlorophyll‐a content ,one for chlorophyll‐b content and one for total chlorophyll content .They were located in mmc0501‐bnlg1451 on chromosome 10 and explained 6.77 to 6.93% of the phenotypic variance each .Six QTLs were detected at the pollination stage ,one for net photosynthetic rate , one for stomata conductance ,two for intercellular CO2 concentration and two for transpiration rate ,and they explained 8.65% to 9.87% of the phenotypic variance each .For population R ,three QTLs for chloro‐phyll‐a content ,two for chlorophyll‐b content and three for total chlorophyll content were detected at the five‐leaf stage ,one of which (qRFCt‐1‐2) was a main effect QTL with a contribution of more than 10% . Two QTLs for chlorophyll‐a content ,three for chlorophyll‐b content and two for total chlorophyll content were detected at the milk stage .Two QTLs for net photosynthetic rate ,one for stomata conductance ,one for intercellular CO2 concentration and one for transpiration rate were detected at the pollination stage ,and they explained 5.79 to 9.24% of the phenotypic variance each .No consistent QTL was detected in the two populations and the contribution rate of a single QTL was low ,which indicated that the photosynthetic traits are quantitative traits controlled by many minor genes and the genetic mechanism is complex .There‐fore intensive study should be done to clarify the genetic mechanism of photosynthetic traits .