Effects Of N,P On Photosynthetic,Sugar Metabolism And Medical Quality Of Lycium Barbarum L.

Ningxia wolfberry (Lycium barbarum L.) is a type of fruit that is both edible and medicinal. In recent years, with the increase of the market demand and the increasing requirements on its quality, how to produce a high yield and high quality wolfberry had become a hot topic of the society, especially by utilizing the innate resistance of wolfberry against salinity. In alkaline soil, to explore the various factors on the high yield and quality of Chinese wolfberry will become the hot topic in the future research. Among all the factors, the soil fertility factors- nitrogen and phosphorus elements are the important factors to affect the yield and quality of wolfberry. This study adopted the alkaline soil that has been modified by modifiers, i.e., desulfurization slag, as the planting soil for wolfberry, and adopted single factor randomized block experimental design to study the effect of different fertilization quantity of nitrogen and phosphorus fertilizers on wolfberry quality and yield. The results showed that:1. In the ripe fruit, the vertical and horizontal diameters increased along with the increase of nitrogen and phosphorus fertilizer, showing a decreasing trend; while the weight of 100 wolfberry fruits showed the trend of increase first and then decrease, and the vertical and horizontal diameters and the weight of 100 wolfberry fruits at the first batch and in the full fruiting period are bigger than in the last fruiting period.2. In the ripe wolfberry fruit, the amount of glucose and fructose were positively correlated with the fertilization quantity of nitrogen and phosphorus fertilizers; in the ripe wolfberry fruit, the content of sucrose differs under different levels of nitrogen and phosphorus fertilizers, but the highest levels appear respectively at N2 of nitrogen fertilizer and P4 of phosphorus fertilizer.3. In ripe wolfberry fruit, the correlation between polysaccharide content and the nitrogen fertilization quantity showed an increasing trend, but the correlation between polysaccharide content and the phosphorus fertilization quantity showed an decreasing trend; the content of flavonoids increases first and then decreases along with the increasing fertilization quantity of nitrogen fertilizer; on the contrary, the content of flavonoids decreases first and then increases along with the increasing fertilization quantity of phosphorus fertilizer; the content of betaine in ripe wolfberry is proportional to the fertilization quantity of nitrogen fertilizer, and inversely proportional to the fertilization quantity of phosphate fertilizer.4. When the fertilization quantity of nitrogen is 50kg/667m2, the max sum of contents of flavonoids, polysaccharides and betaine in ripe wolfberry fruit was 3.57%, and the optimal regression equation is:y=-0.00043x2+0.04305x+2.494 (x:kg/667m2, y:%, R=0.96794); when the fertilization quantity of phosphorus is 0 kg/667m2, the max sum of contents of flavonoids, polysaccharides and betaine is 3.95%, and the optimal regression equation is:y=0.00042x2-0.04305x+3.95 (x:kg/667m2, y:%, R=0.90794).5. When the fertilization quantity of nitrogen is 39.39 kg/667m2, the max yield is 91.12 kg/ 667m2. The optimal regression equation is:y=-0.0393x2+3.0964x+30.013 (x:kg/667m2, y:kg/667m2);when the fertilization quantity of phosphorus is 23.75 kg/667m2, the achieved max yield was 160.63 kg/667m2. The optimal regression equation is:y=-0.147x2+7.020x+27.83 (X:kg/667m2, Y:kg/ 667m2).Based on the experiments and research, we found out the optimal quantity of fertilizers to be applied for achieving the best yield of wolfberry on the alkaline soil and the best fertilization quantity of effective components, so we provided the theoretical basis for large-scale planting of wolfberry on alkaline soil and for the scientific and reasonable fertilization.