Differences of Photosynthetic Characteristics in the Nitrogen Efficiency Genotypes of Eggplant under Low Nitrogen Stress

Four nitrogen efficiency genotypes of eggplant were used to study the photosynthetic characteristics under the normal and low nitrogen stress during the five leaves and eight leaves stages.The results showed that the photosynthetic rate(Pn),chlorophyll relative content(SPAD)and the maximum photochemistry efficiency(Fv/Fm)under the low nitrogen stress displayed a tendnrcy of rising first then decreasing.All the indexes above were remarkerbly lower than those under the normal nitrogen supply.Compared with other genotypes,the photosynthetic characteristics of the double-high nitrogen efficiency genotype(which is high efficient under the normal and low nitrogen stress)are much better.