Studies On Regulated Mechanism Of Berry Loading To Photosynthesis In Grapevine With "厂" Shape Training System

In order to study the effect of tree volume loading on the photosynthesis of grapevine under the "厂 " shape training system. Taking 5 years-old "Cabernet sauvignon" and "Merlot" as experimental materials,1 have researched the effects of three berry loading treatments (0.25kg/cm2、0.5kg/cm2、 0.75kg/cm2) with " 厂" shape training system on grapevine development, photosynthetic characteristics and its key enzyme activity of leaves, the activity of sugar metabolism key enzymes in fruits and leaves. The results showed as follows:1 Compared with "Dulong" training system, with the decrease of the berry loading in "厂" shape training system, the leaf area and dendrite length of grapevine has increased, which 0.25kg/cm2 treatment of leaf area and dendritic length was significantly higher than that of control.2 With the increase of berry loading, the chlorophyll a, chlorophyll b, carotenoid, net photosynthesis rate increased, key enzyme of photosynthesis in the leaves of grapevine, Rubisco, Mg2+-ATPase, Ca2+-ATPase, SPS activity increased. Chlorophyll content of leaves treated with 0.5kg/cm2 was significantly higher than that of 0.25 kg/cm2 in the process of photosynthesis.3 With the reduction of the berry load, NI, CBAI, SS, SPS activity in the berry of grapevine showed an increasing trend, while AI, Mg2+-ATPase and Ca2+-ATPase activity had a trend of decrease. The berry load in 0.25 kg/cm2 and 0.5 kg/cm2 were beneficial to the increase of leaf and berry sugar accumulation and enzymes related to sucrose metabolism activity.4 "厂" shape training system in 0.25kg/cm2 treatments can significantly improve total soluble sugar, total phenol, tannin, anthocyanin and total anthocyanin content of grapevine. There was no significant difference in 0.5 kg/cm2 with the berry quality.In summary, under "厂" shape training system, the tree volume loading of grapevine can affect the activity of photosynthesis related enzymes in leaves and the activity of sucrose metabolism related enzymes in grape, so that it can adjust the relationship between the source and sink, and improve the efficiency of photosynthesis. Besides it can enhance the growth and development of the plant and improve the quality of the berry, lay a good foundation for the high quality winemaking. For Helan Mountain wine grape producing areas, the reasonable tree volume loading for "Cabernet Sauvignon" and "Merlot" is about 0.5kg/cm2 with "厂" shape training system.