The invention discloses a
screening method for spring-rape high-photosynthetic-efficiency
germplasm. The
screening method includes the steps that the net photosynthetic rate, the
stomatal conductance,the intercellular CO2 concentration, the
transpiration rate, the stomata limiting value and the
water use efficiency of leaves and pods are measured; photosynthetic areas of spring-rape green pod skins are measured; the photoresponse curve and the CO2 response curve are measured; 1) long petiole leaves, short petiole leaves, sessile leaves and the pod net photosynthetic rate of a to-be-selected material at the
seedling stage, the
bolting stage, the flowering stage and the pod stage are compared with long petiole leaves, short petiole leaves, sessile leaves and the pod net photosynthetic rateof the comparison variety 'Qing hybridization 7' at the
seedling stage, the
bolting stage, the flowering stage and the pod stage, then an average value is solved, and a material higher than 5% of thecomparison group is a primary high-photosynthetic-efficiency material; 2) the photoresponse curve and the CO2 response curve of the short petiole leaves at the
seedling stage and the
bolting stage aremeasured; light saturation points, light compensation points and the light
quantum efficiency are computed through the
light response curve, and the
carboxylation efficiency, CO2 compensation pointsand CO2 saturation points are computed through the CO2 curve;
germplasm at least having a highlight saturation point or low CO2
compensation point serves as a final high-photosynthetic-efficiency material.