Multi-location evaluation of gene pyramided lines of MTU 1010 and JGL 1798 against bacterial blight of rice

摘要

Cottondora Sannalu (MTU 1010) and Jagtial Sannalu (JGL1798) are widely cultivated rice varieties in Telangana and Andhra Pradesh and very well-accepted among the farmers because of their high yield, slender grain and preferred cooking quality. Despitebeing popular, these varieties are susceptible to different pests and diseases including bacterial blight (BB), caused by Xanthomonas oryzae pv. oryae (Xoo).Two BB resistance genes viz., xa13 and Xa21 were introgressed in these two varieties using marker assisted backcross breeding. Homozygous lines possessing BB resistance genes xa13 or Xa21 and their combination were evaluated for BB resistance with multiple Xoo isolates under controlled condition in glass house and also at different hot spot locations in the states of Telangana and Andhra Pradesh, India. Both the recurrent parents (MTU 1010 and JGL 1798), TN1 (susceptible check variety) and Improved Samba Mahsuri (resistant check variety) were also subjected for resistance evaluation. All the gene-pyramided lines were highly resistant to BB both under glasshouse and field condition. Individually, BB resistance gene xa13 showed higher level of resistance than Xa21.7he resistance level was higher in the lines possessing both the BB resistance genesin comparison to the lines possessing single BB resistance genes. The results showed that combination of BB resistance genes xa/3and Xa21 can provide broad level of resistance against BB in Telangana and Andhra Pradesh.