Identification of sugarcane yellow leaf virus resistance in Saccharum parental hybrids in India

Abstract

Yellow leaf disease (YLD) is one of the important viral diseases in sugarcane. It is caused by Sugarcane yellow leaf virus (ScYLV), a positive sense single stranded RNA virus primarily transmits through infected setts and secondarily transmits through aphid Melanaphis sacchari. Earlier, it was identified as a minor disease in India, but in recent years it attained the epidemic status with the disease incidences from 30 to 50 % in plant crop and more than 70% in ratoon crops which significantly affected the crop productivity. At present, it is being effectively managed through tissue culture derived virus free planting materials. However, after transplantation of TC plants in the field, it succumbed to the virus and made difficulties to sustain the high yield and high sugar varieties in field for long time. Hence, the present study was taken up to identify the yellow leaf (YL) resistant lines from the large pool of parental and commercial hybrids. During the year 2015-21, YLD incidence, ScYLV resistant (apparent) and susceptible lines were identified based on natural screening in parental population maintained at National Hybridization Garden, ICAR-SBI, Coimbatore. The highest YLD incidence of 24.20% was observed with least 75.63% resistance during the year 2021 followed by 23.70% incidence with 76.33% resistance in 2019. In contrast, the least YLD incidence of 7.90% with high resistance of 92.09% was observed during the year 2017. During last seven years, YLD incidence was observed in the ranges of 7.90% to 24.20% in the parental population. Based on seven years of field phenotyping, 105 apparently resistant lines were identified in the study which could be used for YL resistant breeding programme in the future.

Keywords

• yld incidence; field screening; scylv resistant lines