PHOTOSYNTHETIC CAPABILITY OF 12 GENOTYPES OF TRITICUM AESTIVUM

Photosynthetic capabilities of 12 different genotypes of Triticum aestivum L. were studied,including 2 cultivars from Beijing area. The results showed that net photosynthetic rate (Pn) of cultivars Xiaoyan 22,Shanmai897 and 8901-11-5 exceeded 20 μmol CO_2·m -2·s -1,and were higher than the other cultivars studied. The overall photochemical quantum yield of PSII (Yield),the coefficient of photochemical fluorescence quenching (qP) and the water use efficiency (WUE) of these three cultivars were also higher. While their dark respiration rates (Rd) and coefficients of non-photochemical fluorescence quenching (qN) were lower. The results illustrated that the photosynthetic and physiological functions of three cultivars mentioned above were by far the best among the 12 tested cultivars,and that these parameters had a pattern of chain interrelations. It is suggested that if winter wheat cultivars from other parts of the country are to be introduced into Beijing area as field-grown cultivars or as parent material for hybrid breeding,the above three cultivars should take top-priority of among 10 cultivars we studied.