Biological Resistance to Okra yellow vein mosaic virus Using Three Biological Agents on Three Okra Cultivars

Jadoua, J.A. and M.A.W. Al-Fahd. 2022. Biological Resistance to Okra yellow vein mosaic virus Using Three Biological Agents on Three Okra Cultivars. Arab Journal of Plant Protection, 40(2): 148-157. https://doi.org/10.22268/AJPP-40.2.148157 A study was conducted in Al-Alam District, Salah Al-Din Governorate, Iraq, during the fall season 2019-2020, with the goal of diagnosing the local isolate of Okra yellow vein mosaic virus (OYVMV) from infected plants using polymerase chain reaction. A genomic segment of OYVMV with a size of 750 was amplified using polymerase chain reaction (PCR) and a set of specific primers. By amplifying a 750 bp band on agarose gel, the field isolate tested was identified as a member of the genus Begomovirus, which was related to an Indian isolate of the same virus. The study included determining the efficacy of three biological factors: (A) a medicinal plant preparation from A. Paniculara, (H) a preparation from Lion's mushroom (H. erinaceus and (P) a preparation from P. florescence bacteria which has impact on virus infection, as well as determining the response of three okra varieties to virus infection. The use of the three combined factors (A+H+P) outperformed other treatments reducing virus infection rate of the Petra okra variety to 26.67 % and severity to 10.66 % as compared to 100% for the control. The findings showed that there were substantial variation in the peroxidase enzyme activity and chlorophyll content, with the A+H+P treatment producing 59.14 units/mg protein for the Petra variety and 40.81 Spad for the Hasnawi variety. The results also showed that there were extremely significant differences in yield, with the triple treatment (A+H+P) yielding 833.96 gm/plant for the Star variety compared to 537.44 gm/plant for the infected control that was not treated. Keywords: Biological control, viruses, okra