Effect Of Nitrogenous Fertilizer, CPPU On The Quality And The Compare On Cultivars Of Lagenaria Leucantha

With enormous increase of vegetable output in recent years, focus of our efforts in vegetable production has been changed from high yield to high quality. People gradually pay more attention to the nutritional quality and healthy functions of vegetables with the increase of living standard. Calabash gourd (lagenaria leucantha Rusby.) is a member of the Cucurbitaceae family, commonly known as the cucurbit family. It has been widely used as delicious and nutritional food, and is particularly popular in China. Nitrogen is essential nutrient elements for growth and development of vegetable, being concerned with photosynthesis, respiration and the metabolism of protein and carbohydrate in plant. CPPU selected from plant growth regulators recently is a kind of cheap cytokinin-like substance. Its activity is many times higher than generally cytokinin (CTK). It can increase both the fruit set and fruit size, improve the fruit quality, induce the fruit Parthenocarpy and so on. So, for carrying the high yield and high quality of lagenaria leucantha, this research is to study the impact of nitrogenous fertilizer, CPPU on the quality of lagenaria leucantha, and the difference of cultivars of lagenaria leucantha.1. Effects of nitrogenous fertilizer with three levels (10,25,50 kg/667 m~2) and two methods (the high dose of nitrogen was applied early or later in the same level of nitrogen) on the nutritional quality of fruit in Lagenaria leucantha (cv. Yonghu 1 hao) were studied in trials. The results showed that increasing nitrogen appilication increased significantly the contents of Chlorophyll a, b in the leaf and vitamin C, nitrate, mineral elements N,P,Mg in the fruit of Lagenaria leucantha. It also increased the contents of soluble protein and free amino acid, but decreased the soluble sugar content and the reducing sugar content in the fruit. The high dose of nitrogen was applied early rather than later decreased the nitrate content of ftuit. The contents of vitamin C and some mineral elements in the fruit of Lagenaria leucantha descended when superfluous nitrogen was supplied.2. Effects of nitrogenous fertilizer with three levels (10,25,50 kg/667 m~2) and two methods (the high dose of nitrogen was applied early or later in the same level of nitrogen) on the phenolic compounds contents and antioxidant potential of fruit in Lagenaria leucantha (cv. Yonghu 1 hao) were studied in trials. The results showed that increasing nitrogen appilication decreased the contents of totle phenolics and totle flavonids, also decreased DPPH radical scaveging in the fruit of Lagenaria leucantha. The FRAP value of fruit was first increased and then decreased with the increase of nitrogen appilication. The different methods of nitrogen application had not any significant effects on the quality in the fruit.3. Effects of CPPU with four levels (20,30,40,50 ppm) and 0 ppm (CK, artificial pollination) on the nutritional quality of fruit in Lagenaria leucantha (cv. Yonghu 1 hao) were studied in trials. The results showed that compared with the control, the contents of soluble sugar and vitamin C increased, but free acid content had not any significant changes in the fruit of Lagenaria leucantha treated with CPPU. With the increase of concentration of CPPU, vitamin C content in fruit was first increased and then decreased, free acid content was also increased gradually. However, there were no significant differences among treatments.4. Compare on the cultivars of Lagenaria leucantha: Six cultivars of Lagenaria leucantha which are Yonghu 1 hao, Yonghu 2 hao, Hangchangpu-1-2, 02-2-1, 02-2-1-3, 02-2-1-5 were choosed for the compared experiment including the phonological period, the plant character, the economy character and the quality in Lagenaria leucantha. The results showed that all of the cultivars above riped earlier. 02-2-1-3 does not suit to be a cultivar and it can be used for research, because its fruit and plant are bitter. Thought about the economy character, the yield, the quality, Yonghu 1 hao, Yonghu 2 hao and 02-2-1 have high yield and high quality, which can be spread and exported.