Muharrem Güleryüz

Promising native summer apple (Malus domestica) cultivars from north-eastern Anatolia, Turkey

Abstract This study was conducted on summer apple (Malus domestica) trees growing wild in the Çoruh Valley, north‐eastern Anatolia, Turkey. The research material consisted of uncultivated summer apple trees. Out of 250,10 trees not infected by apple scab (Venturia ineaqualis) were selected. Fruit characteristics of these superior types were evaluated. The ranges of fruit characteristics determined for the selected types were: 49.5–152.2 g fruit weight, 42.8–65.3 mm fruit length, 52.3–75.7 mm fruit width, 10.3–13.8% total soluble solids, 4.88–7.44 mg vitamin C/100 g, 0.19–1.43% total acidity (as malic acid), 9.33–12.06% total sugar, and 6.31–8.94% reducing sugar. Some selections ripening in mid July should be compared with common summer apple cultivars for their agronomic characteristics or used as breeding partners for further breeding efforts.

Effects of Some Plant Growth Promoting Rhizobacteria (PGPR) on Graft Union of Grapevine

ABSTRACT In this study, effects of topical applications of three plant growth promoting rhizobacteria (PGPR) strains (Pseudomonas BA8, Bacillus BA16 and Bacillus OSU142) on graft union were evaluated in terms of success rate, callusing rate, callusing degree and full callusing rate on four different rootstock-scion combinations including 41B-Beyaz Çavuş, 41B-Italia, 5BB-Beyaz Çavuş and 5BB-Italia. The results showed that in general all of the bacterial strains had significant effects on all parameters tested in all rootstock-scion combinations compared with the control. Application of Pseudomonas BA8 in 41B-Beyaz Çavuş, Bacillus OSU142 in 41B-Italia, Pseudomonas BA8 in 5BB-Beyaz Çavuş, and Bacillus BA16 and Bacillus OSU142 in 5BB-Italia combination increased the success rate (83.3%, 93.3%, 80.0% and 86.7%, respectively) compared with the control (23.3%, 80.0%, 60.0% and 70.0%, respectively). Application of PGPR also increased the callusing rate, callusing degree and full callusing rate in all rootstock-scion combinations compared with control. Among the bacteria strains tested, Pseudomonas BA8 was the most effective PGPR strain which can be used for graft union of grapevine grown in commercial, sustainable or organic agriculture.

Effects of auxins and cytokinins on graft union of grapevine (Vitis vinifera)

Abstract The aim of this study was to determine the effects of some auxins and cytokinins on graft union and root formation of grafted cuttings of four different grapevine (Vitis vinifera) graft combinations (41B‐Erenköy Beyazi, 41B‐Italia, Rupestris du Lot‐Erenköy Beyazi, and Rupestris du Lot‐Italia). The cut grafting surfaces of both the scion and rootstock were first dipped into either 1 ‐naphthaleneacetic acid (NAA), indole‐3‐butryic acid(IBA), benzyladenine (BA), or kinetin (Ki) for 20 s. NAA and IBA were applied at concentrations of 500, 1000, and 2000 mg/litre and BA andKi were applied at rates of 250, 500, and 1000 mg/litre. Following this treatment the cuttings were grafted, stratified, and hardened. Control group cuttings were grafted without any application. Results showed that the physiological effects of cytokinins differed from auxins. In general, Ki and BA stimulated rapid proliferation of callus between the scion and rootstock whereas NAA and IBA increased root formation at the basal end of grafted cuttings compared with the control. The best results were obtained from treating the graft cut‐surfaces of graft combinations with 250 and 500 mg/litre Ki or BA. Except for the 1000 mg/litre concentrations, Ki and BA showed better callusing rate and callusing degree at grafting point of all tested graft combinations compared with the control, whereas rooting rate and rooting degree were enhanced by application of IBA and NAA compared with the control. In all graft combinations, the highest success rate (100%) was obtained from 250 mg/litre Ki application. Significant increases in success rate and callus formation as callusing rate and callusing degree at the grafting zone indicated that the Ki and BA may have the potential to improve graft union formation.