IMPROVED QUALITY OF VIRAL INFECTED GRAPE PLANTS CULTIVATED IN SOIL INOCULATED WITH RHIZOPHERIC MICROORGANISMS

A considerable rhizopheric bacteria and mycorrhizae collectively known as plant growth promoting microorganisms (PGPM) have ability to induce acquire resistance in plant against pathogens and to provide benefits to their hosts. Grapevine viruses cause reducing yield and shortening the life span of infected plants in the vineyard. The current study aims to improve quality of Grape fan leaf virus (GFLV) infected grape plants via the soil inoculation with PGPM. Pot experiments were conducted under greenhouse during two seasons 2014/15 and 2015/16 in a Virology Greenhouse, Microbial. Dep. Fac. Agric., Ain Shams Univ. Cairo, Egypt. Grape cv. Flam grafted with GFLV infected stick and cultivated in inoculated soil with rhizopheric PGPB and mycorrhiza (VAM). GFLV was detected in infected leaves by DAS-ELISA. Plant growth parameters and chemical immune acquired resistance were assessment in GFLV infected grape cv. flam. The results were clearly indicated that PGPM inoculation in soil improved of plant growth in the second season (2015/16) compared with first season (2014/2015(. PGPM (Bacillus sp., Pseudomonas sp. and Serratia sp. isolates and VAM) improved quality of GFLV infected grape plants via increased plant growth parameters (leave number, stem diameter, plant length, and phosphorus and potassium components in leaves). PGPM induced acquire resistance in plant against GFLV; it was found that, significant increase of proline and SA contents in GFLV infected grape  leaves compared as healthy ones. The results revealed that chlorophyll a; b and carotenoids were significant decreased while inoculated PGPM in soil showed significant increase compared with healthy control ones. Expressed proteins and resistance enzymes (POD and PPO) of antiviral proteins were significant increase in PGPM application of GFLV infected grape growth related no inoculated PGPM ones. So that the current study recommended that the combination among VAM and PGPB soil inoculation improved quality of GFLV infected grape plant under greenhouse conditions.