Allelopathic effects of rhizobacteria on Fusarium wilt and on the growth of citrus seedlings in Adjara, Georgia
Allelopathic effects of rhizobacteria on Fusarium wilt and on the growth of citrus seedlings in Adjara, Georgia
- Author(s) Otar Shainidze, Shakro Kanchaveli and Guram Chkhubadze
- Year: 2024
- Month: March
- Volume: 61
- Pages: 165-174
The allelopathic potential of rizobacteria was investigated on root rot/wilt and on the growth of Citrus reticulata Blanco, Citrus limon Burmann and Citrus sinensis [L.] Osbeck seedlings. The highest means of incidence of disease and severity were recorded for lemon transplants (38.6 and 27.6.0 %, respectively) followed by mandarin transplants (34.5 and 23.8 %), while orange transplants revealed the lowest means (24.3 and 13.9 %). The most frequently fungi isolated from rotted roots of the citrus transplants were Fusarium oxysporum, F. solani and F. proliferatum. In pathogenicity tests, all the tested fungi were pathogenic to mandarin, lemon and orange transplants. The effect of plant growth promoting rhizobacteria (PGPR) individually and/or mixed when used as a soil drench treatment varied in reducing root rot/wilt incidence and severity under greenhouse conditions compared with control. The mixed culture of PGPR recorded the highly significant reduction in severity of root rot/wilt disease as compared to when the PGPR strains were used individually. On the other hand, the mixed culture of PGPR recorded the highest protection against infection with F. oxysporum (95-96 %) followed by F. solani (93-94 %) and F. proliferatum (89-91 %) in case of mandarin, lemon and orange transplants. Also, all treatments significantly increased plant height (cm), number of leaves transplanting-1, leaf area (cm2), fresh and dry weights transplanting-1(gm) compared with control treatment. This study indicated that soil drenched with PGPR strains can be used as a safe control measure of the disease in citrus transplants and as a stimulant of vegetative growth parameters
