Impact of Thermotherapy on Regeneration of Single Node Setts of Sugarcane Infected by Sugarcane Yellow Leaf Virus

Abstract

Sugarcane is an important cash crop in India, as well as a key raw material in the production of sugar, jaggery, and bioethanol. Sugarcane yellow leaf disease incited by Sugarcane yellow leaf virus (SCYLV) is emerging as a major threat to sugarcane cultivation and the canes infected by SCYLV were found to be frequently invaded by fungal pathogens. SCYLV infected canes when used as seed material recorded low germination and seedling vigour. Hence, the present investigation was undertaken to test the efficacy of thermotherapy followed by carbendazim treatment for enhancing germination of SCYLV infected seed setts and seedling vigour. Single node setts of SCYLV infected canes were subjected to thermotherapy at 50°C, 51°C and 52°C for 10, 20 and 30 minutes in a hot water bath. Single node setts dipped in water or carbendazim (0.1%) solution served as control. Results of the study revealed that sett treatment with hot water at 50°C for 20 min followed by dipping in carbendazim (0.1%) solution for 30 minutes enhanced the sett germination and vigour of virus infected single noded setts. The presence of SCYLV in the seedlings that had emerged was determined using RT-PCR. The virus was found in germinated seedlings even after thermotherapy, suggesting that at the temperatures tested, thermotherapy was ineffective in eliminating the SCYLV sett borne inoculum. Thermotherapy and fungicide treatment, on the other hand, improved the germinability of infected single noded setts, probably due to a reduction in secondary fungal infection.

Keywords

• hot water treatment
• rt-pcr
• saccharum officinarum
• sett germination
• yellow leaf disease