Occurrence and Distribution of Bacterial blight of Clusterbean incited by Xanthomonas axonopodis pv. cyamopsidis in major growing area of Rajasthan.

Guar, also known as clusterbean, is a member of the Leguminosae (Fabaceae) family. Its genus
Cyamopsis contains three species: C. tetragonoloba, C. senenglensis, and C. serrata. The most
extensively farmed of these is C. tetragonoloba, followed by the other two. The pathogen that
causes leaf blight, is Xanthomonas axonopodis pv. cyamopsidis, drastically reduces plant stand
and can produce up to 58% less in cultivars. The illness simultaneously manifests as leaf spot
and blight. During the Kharif seasons of 2018 and 2019, a roving study carried out in the main
clusterbean-growing areas of Rajasthan confirmed the presence of the bacterial blight caused by
Xanthomonas axonopodis pv. cyamopsidis. No district or location in the examined districts was
totally devoid of the bacterial blight illness. Hanumangarh (30.23%) had the highest disease
severity, and Barmer (17.54%) recorded the lowest. Cluster bean was more susceptible to
Xanthomonas axonopodis pv. cyamopsidis infection at the maturity stage and 30 days after
planting in the months of October and November, when the temperature starts to fall. The state's
locations varied in terms of the severity of the sickness as a percentage. Results showed that
compared to sprinkler and rainfed environments, illness severity was more frequently found
under flood irrigation conditions.