Application of Animal Manure and Plant Growth- Promoting Rhizobacteria as Effective Tools to Control Soil Nematode Population and Increase Crop Yield in Grapevine Orchards

A survey of nematode community in grapevine plantations grown in Belbes, Sharqia, Egypt revealed the presence of nine plant-parasitic nematodes genera namely Aphelenchus, Criconemoides, Ditylenchus, Helicotylenchus, Pratylenchus, Meloidogyne, Longidorus, Tylenchus and Tylenchorhynchus; free-living nematodes (FLNs) belonging to the genus Rhabditis and predacious nematodes (PNs) belonging to order Mononchida. Nematodes were found with a different frequency of occurrence and population density. Pratylenchus gained a high population density (PD) followed by Tylenchus, Meloidogyne and Helicotylenchus. A higher prominence value (PV) was found with genus Pratylenchus (190.75) while, the genera Meloidogyne, Tylenchorhynchus and Tylenchus were found with moderate prominence values. Animal manures are effective tools in sustainable soil health and agricultural systems. Therefore, the influence of three livestock manures as feasible practices with BECTO Grow Roots®, a commercial plant growth-promoting bacterium (PGPB) on nematode community and plant growth and fruit yield of grapes, Vitis vinifera L. cv. Flame was undertaken. Soil samples were collected at five-time intervals. Composted animal manures significantly (P ≤ 0.05) minified numbers of plant-parasitic nematodes (PPNs). The greatest effect was recorded with oxamyl after two months of treatments followed by chicken, sheep and cow manure. Conversely, at four and five months after application, animal manures were the most effective. Moreover, a noticeable abundance of FLNs and PNs numbers was detected. The highest increment was achieved in soil amended with chicken manure followed by sheep and cow manure whereas oxamyl reduced numbers of FLNs and PNs as compared with untreated vines. Application of manures against PPNs particularly M.incognita decreased numbers of J₂/250/soil in vines amended with chicken, cow and sheep manure, respectively and increased numbers of FLNs and PNs. Population densities of M.incognita J₂/250 g soil were significantly minimized (1.55 J₂/250 g soil) in blocks amended with commercial rhizobacteria and chicken manure. Maximum total fruit weight and leaf numbers were achieved in vines treated with rhizobacteria +chicken, cow and sheep manure, respectively. This study proved that composted chicken, cow and sheep manure applied alone or in combination with PGPB can be a promising tool for the management of phytoparasitic nematodes, enrichment of FLNs and PNs and improvement of plant growth and grapevine yield.