Cafer Köse

Seaweed extracts improve copper uptake of grapevine

The objective of this study was to determine the effect of seaweed extract on macro and micro nutrient uptake of grapevine (Vitis vinifera L. cv. Karaerik). One-year-old grapevine (Vitis vinifera L. cv. Karaerik) saplings were planted in perlite with different nutrient element levels under greenhouse conditions. Three seaweed extracts, Maxicrop, Proton and Algipower, were sprayed on the foliage at different concentrations (0, 0.5, 1.0 and 2.0 g l−1). Results indicated that foliar application of seaweed extract increased Cu uptake of grapevine in the growth media which had insufficient nutrient elements. No significant differences in nutrient uptake of grapevine were obtained among the three seaweed extract types. The results showed that nutrient element level of growth media was more effective on stimulation of N, P, K, Ca, Fe, Mg, Mn and Zn uptake than seaweed extracts. In contrast, seaweed extract was more effective in supporting Cu uptake in vines than nutrient element level of growth media.

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.

Comparative evaluation of oxidative enzyme activities during adventitious rooting in the cuttings of grapevine rootstocks.

BACKGROUND This study investigated changes in peroxidase (POX) and polyphenol oxidase (PPO) activities through adventitious rooting in hardwood cuttings of grapevine rootstocks. Three grapevine rootstocks with different propensity to produce adventitious roots were selected: recalcitrant (Ramsey), non-recalcitrant (Rupestris du Lot) and intermediate (99R) cultivars. RESULTS The averages of root number at 65 days were 96 in Lot, 76 in 99R and 30 in Ramsey. Both enzyme activities characteristically increased before adventitious rooting, regardless of rooting ability of the rootstocks, and then decreased. POX activity increased in Ramsey cuttings at 22 days, in Lot and 99R cuttings at 14 days after planting, and then decreased gradually until 51 days. The highest POX activity was determined in Ramsey rootstock with the highest rooting ability and the lowest activity was determined in the rootstocks with the lowest rooting ability. PPO activity gradually increased in Ramsey rootstock cuttings from 10 days to 22 days, in Lot and 99R cuttings at 14 days, and then decreased until 51 days. A significant correlation was identified between high POX activity and adventitious rooting capability in rootstocks, but the same result was not determined with PPO activity. CONCLUSION A recalcitrant rooting variety cannot increase POX activity sufficiently before rooting. Therefore applications that could increase POX activity in stem cuttings during rooting may facilitate increased rooting in such rootstocks.

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.