Effects Of Light Intensity,Temperature,Nutrition At Seedling Stage On The Occurrence Of Malformed Fruit In "Chuanfan Zajiao No.1" Tomato

Tomato cultivar "Chuanfan Zajiao No.1" was used in this experiment. After treatments with various light intensity, temperature and nutrition during seedling stage, the physiological and biochemical characters in stem apex of tomato seedling, the occurrence of malformed flower and malformed fruit were analyzed. Followings are the results:1. With the increase of light intensity during tomato seedling stage, the content of soluble protein, soluble carbohydrate and starch enhanced obviously, and the activities of PPO and NR increased, while the activity of CAT decreased. Simultaneously, the rate of malformed flower in the first inflorescence enhanced significantly; the rate, average grade and integrated index of malformed fruit increased significantly.2. With the reducing of temperature at night during tomato seedling stage, the content of soluble protein, soluble carbohydrate and starch increased evidently, the activities of POD, PPO, CAT and NR promoted obviously. Low temperature treatment at night could increase significantly the rate of malformed flower, and the incidence, average grade, integrated index of malformed fruit, which were the highest in 6°C night temperature, the rate of malformed flower was 62.32%, 52.67%, 57.57% in the first inflorescence, the second inflorescence and the average of two inflorescences respectively. The rate of malformed fruit in the first, the second and the average of two clusters was 56.21%, 53.97%, 55.05% respectively. The average grade was 2.70 and integrated index of malformed fruit was 0.2361. Low night temperature also influenced significantly the rate of the dehiscent fruit, finger and twin fruit, and mixed shape fruit.3. With the increase of nitrogen and phosphorus application during seedling stage, the content of the soluble protein, soluble carbohydrate and starch increased obviously, as wellas the PPO activity. The POD and NR activity promoted with the rising of nitrogen application, the POD activity decreased with the increasing of phosphorus application. At the same time, the rate of malformed flower and malformed fruit, average grade and integrate index increased significantly with the increase of nitrogen application.According to the effects of light intensity, temperature and nutrition on occurrence of the malformed flower and malformed fruit of "Chuanfan Zajiao No.l" in this experiment, during tomato seedling stage, low night temperature was the most important environmental reason that induce occurrence of malformed fruit, nitrogen content was the second one. Light intensity also plays an important role on the occurrence of malformed fruit. Therefore, the night temperature had better be above 12°C, redundant nitrogen could not produce vigorous seedling during the phase of tomato seedling. The best nitrogen concentration was about 120~ 150 mg/L, the best phosphorus concentration was 180 mg/L, and the best potassium concentration was 120^140 mg/L, which not only promoted the growth of the seedling, but also prevented the high incidence of malformed fruit.