[Effects of irrigation amount at seedling stage on physiological characteristics and yield of peanut]

Taking two peanut varieties with different drought-resistance Luhua 11 and Nongda 818 as test crops, the effects of different irrigation amount at seedling stage on their physiological characteristics and yield were studied from 2003 to 2004. The results showed that with decreasing irrigation amount, the leaf photosynthesis rate of test varieties decreased, while malondialdeyde (MDA) content increased. Watering 60-80 mm ( suitable drought) enhanced the activities of superoxide dismutase (SOD) , peroxidase (POD) and catlase (CAT) , and increased the content of soluble protein. After re-watering by the end of treatments, the activities of SOD, POD and CAT and the contents of soluble protein and MDA decreased significantly, while photosynthesis rate increased obviously. The pod and kernel yield decreased with decreasing irrigation amount, and Luhua 11 had a greater loss than Nongda 818, indicating that Nongda 818 was more drought-tolerant than Luhua 11. It was suggested that under water-saving culture, the irrigation amount at seedling stage could not be less than 80 mm for Luhua 11, and less than 60 mm for Nongda 818.