Study On The Effects Of Rootstocks On Tree Growth And Photosynthetic Characteristics Of Sweet Cherry(Prunus Avium.L)

Using domestically commercially available graft combinations seedlings, planted in the spring, 2006, in consisting of scions of sweet cherry(Prunus avium L.) varieties in dominance which included'Hongdeng','Labinsi','Zaodaguo','Meizao','Zaoshou'and'Santina', on a vigorous rootstock'Daqingye'(P. pseudocerasus L.) which acted as the check rootstock or a dwarfing rootstock'Gisela5'(G5)(P.cerasus ) or two semi-vigorous rootstocks which were Gisela6(G6)(P.cerasus) and ZY-1 (P.cerasus L.), we tried to evaluate the effects of these four promising rootstocks on the phenology, tree growth(vegetation and reproduction), fruit quality, and leaf characteristics of these tested sweet cherry varieties. The investigation result showed that the phenology differed among these tested sweet cherry varities caused by rootstocks, and that G5 and G6 rootstock could accelerate the process of phenology of'Zaoshu'and'Hongdeng'. These tested variety scion and rootstock combinations displayed diverse growth effect which depended on the overground and underground interactant, and the dwarfing rootstock(G5) and semi-vigorous rootstocks(G6,ZY-1) had the capability of reducing growth potential of these estimated sweet cherry varieties. As comprehensive estimation of vegetative growth above graft union considered, it was suggested that some testedcombinations,includingZaodaguo/ZY-1,Zaodaguo/Daqingye,Lapins/G6,Lapins/ZY-1,Lapins/Daqingyed,andHongdeng,Meizao and Zaoshou interacted with all four rootstocks ,had great grafting affinity between scions and rootstocks.and that other combinations, including Zaodaguo/G5, Zaodaguo/G6, Lapins/G5, and Santina interacted with all four rootstocks, had no profitability and longevity of production,. sweet cherry had formed a few flower buds after one completely growth season, and had showed a little capability of fruit-bearing after two completely growth seasons. Rootstock vigor had different effect on the fruit's total soluble solid(TSS) more or less, even significantly, while the rootstock vigor had little effect on the fruit's soluble carbonhydrates(TC), titrable acidity(TA) and vitamin C(Vc). Generally lower ratio of TC to TA in sweet cherry fruits resulted in acid fruit flesh. The contend of chlorophyll a or chlorophyll b in leaves changed with the rootstock vigor, whereas the contend of chlorophyll a plus chlorophyll b remained steadily among different vigorous rootstocks combinated with one sweet cherry variety scion. Photosynthetic potential among all combinations of'Lapins'were not always depending on the content of chlorophyll a plus chlorophyll b. Leaf stoma density which determinated the photosynthetic potential but length and width was not significantly affected by rootstock with different vigor in variety of'Lapins'. The capability of photosynthesis increased with leaf stoma density. Leaf area of'Hongdeng'and'Lapins', grafted on Gi5 or Gi6 rootstock, was significantly smaller than that of'Hongdeng'and'Lapins', grafted on'ZY-1'or'Daqingye'rootstock. Diurnal photosynthetic curve of each combination of'Lapins'displayed a figure of changing tendency with double or trinal peaks in different months.