Influence of supplementation of vineyard soil with organic substances on nutritional status, yield and quality of 'Black Magic' grape (Vitis vinifera L.) and soil microbiological and biochemical characteristics

Abstract

Cost effective and environmentally friendly strategies in plant nutrition are prime considerations for sustainable viticulture in the face of ever-increasing stress factors throughout the world. Therefore, the present study aimed to investigate the effects of applying different types of organic and inorganic material [control (C; no application), basaltic pumice (P), commercial dry compost (DC), pruning residue:farm manure mixture (1:2, v:v) compost (PR+FM), straw:farm manure mixture (1:2, v:v) compost (S+FM), pumice:dry compost (P+DC), pumice+straw:farm manure compost (P+(S+FM)) and pumice+pruning residue:farm manure compost (P+(PR+FM))] to 'Black Magic' grapevines on their agronomic and nutrient acquisition during two consecutive years: 2017 and 2018. The highest yield (6172 g/vine and 7874 g/vine) and cluster weight (411.4 g and 463.2 g) were obtained for the application of S+FM in both years. In terms of berry weight, the highest value was obtained for P+(PR+FM) in 2017, although no significant difference was found between treatments in 2018. PR+FM slightly accelerated berry ripening. The differences between macro and micro element contents of the leaves were statistically significant. The leaf mineral values obtained from pumice were generally higher whether it was applied alone or in combination with other materials. N, P, Ca, Fe and Mn concentrations were sufficient for all applications, while K, Mg and Zn values were within the limits of deficiency. Regarding CO2 production, P+(PR+FM) application in 2017 and S+FM application in 2018 gave the highest values. The effect of organic materials used on microbial biomass-C in soil was higher for S+FM in 2017 and for S+FM and P+DC in 2018 than the other treatments. The application of P+(PR+FM) in 2017 and PR+FM in 2018 had the highest efficiency in terms of dehydrogenase enzyme activity. Urease and phosphatase enzyme values showed a higher activity for P+(PR+FM) in 2017 and P+DC in 2018 than for the other treatments. In this study, we found that applications of organic and inorganic material generally provided good improvement in terms of the agronomic and nutritional properties examined. In order to be able to provide recommendations for appropriate material, it would be useful to evaluate the accumulated effects of the treatments in further research.