Studies on Transmission of Phytoplasma in Sesame
K. Revathi *
Department of Entomology, S.V. Agricultural College, Tirupati-517502, Andhra Pradesh, India.
K. V. H. Prasad
Department of Entomology, S.V. Agricultural College, Tirupati-517502, Andhra Pradesh, India.
M. S. V. Chalam
Department of Entomology, S.V. Agricultural College, Tirupati-517502, Andhra Pradesh, India.
B. V. B. Reddy
Plant Pathology, IFT, RARS, Tirupati, India.
B. R. Reddy
ITDA, Srisailam, Andhra Pradesh, India.
*Author to whom correspondence should be addressed.
Abstract
The experiment was conducted to artificially transmit phytoplasma, the causal organism of sesame phyllody by mechanical sap inoculation and with insect vectors (Orosius albicinctus and Hishimonus phycitis). The experimental findings revealed that the phytoplasma could not be transmitted by sap inoculation. The mean transmission rate was found to be 54.67 per cent, with the highest rate of phyllody transmission (93.33%) observed in both treatments T8 and T9 with 3 insects/plant + 7 Days of Acquisition Feeding (DAF) + 5 Days of Inoculation Feeding (DIF) and 3 insects/plant + 7 DAF+ 7 DIF, respectively, while the lowest was observed in the treatment T1 with 3 insects/plant + 3 DAF+ 3 DIF (13.3%) phyllody transmission from infected to healthy sesame plants. All the treatments were found to be statistically significant over control, however, the treatments T8 and T9 with three insects/plant and with acquisition feeding period of 7 days and inoculation feeding of 5 and 7 days, respectively were found to be at par with each other statistically.
Keywords: Sesame, leafhoppers, sap inoculation, vector transmission