INCOMPATIBILITY ASPECTR THAT APPEAR IN SCION-ROOTSTOCK ASSOCIATION AT SOME PEAR, PLUM AND SWEET CHERRY VARIETIES

Abstract

Introduction. The present studies aim some aspects of the relations between photosynthetic apparatus and plant vital metabolism. A special attention was given to the assimilators pigments. There were analyzed the relations between grafting success percentage, shoots growing and thickness morphological index of the grafting zone as results of a good activity of photosynthetic apparatus (1). Material and Method. The researches were made during 2004 – 2007 and there were studied some pear, plum and sweet cherry varieties. Pear varieties are Cure, Euras, Contesa de Paris and Williams, plum varieties are Stanley, Pescarus, Centenar and Tuleu gras and sweet cherry varieties are Germersdorf, Van, Stella and Boambe de Cotnari. The grafting method used was T budding. The aim was observing the behaviour of those varieties grafted on two different rootstocks: Pyrus sativa Lam. and Cydonia oblonga Mill. for pear, for plum a selection of Prunus domestica L. and Prunus cerasifera Ehrh. and for sweet cherry a selection of Prunus avium L. and Prunus mahaleb L. Results and discussion. Plants photosynthetic activity is determined by complex physiologic processes and an important role in first stages of trees development have growth processes (2). While studying some physiological aspects of scion-rootstock association we find necessary to took into consideration some biometric parameters also. These allowed us to analyze the photosynthetic apparatus and also the whole plant. From the researches we made results that there is a direct correlation between the morphological index of the grafting zone and grafting success percentage. When the morphological index of the grafting zone has a small value, the grafting success percentage is also small and when the index’s value is high the success percentage is also high. The bigger differences on dry substance content that appear show a reduced capacity of dry substance synthesis and a lower flow of glucides through grafting zone. Also, these varieties registered a lower accumulation in chlorophyll and carotenes pigments. Conclusions. The disturbances that appear in assimilated circulation are the result of a low development of roots and glucides stagnation above joining line, fact that determines the scion growing in diameter and also the joining zone at incompatible associations or with a poor compatibility.