Measurement of Phenotypic Variation for Control and Bacterial Leaf Blight Inoculated Rice Lines and Varieties

M H M Mubassir

doi:10.11648/j.bio.20160406.11

Abstract

Bacterial leaf blight (BLB) caused by <i>Xanthomonas oryzae pv. oryzae</i> is a devastating disease of rice, the staple food crop of Bangladesh. Under field condition the disease significantly damages the phenotypic characteristics of the plants affecting the yield. An assessment of the phenotypic variations due to the disease in 10 rice lines and 17 rice varieties were studied at the maximum tillering stage in both natural and induced epiphytotic conditions. Along with the indigenous cultivars the test materials including the check resistant and susceptible cultivars were collected from IRRI. Significant differences in both plant height and the number of effective tillers were recorded in the check and inoculated lines and varieties. Among the rice lines, RC222 resulted the maximum reduction in plant height (3.18%) in the inoculated plants whereas RC217 yielded the minimum reduction of 1.27%. Among the rice varieties, Binadhan-8 and Binadhan-10 showed the maximum reduction in plant height (11.43% and 18.22% respectively) for the inoculated plants where IRBB21, IRBB65 and Kumragur resulted 0% reduction. The number of effective tiller among the rice lines, RC251 yielded the maximum reduction of 26.19% in the inoculated plants whereas RC192 showed as minimum as 4.16% reduction. For rice varieties, Binadhan-8, Binadhan-10 and BR-11 yielded the maximum reduction of 52.62%, 50.07% and 50.06% while IRBB21, IRBB65 and Kumragur showed 0 % reduction. The findings of such phenotypic variations may contribute significantly to the selection of best lines and further research to develop the disease free commercial varieties of rice against the disease.

Highlights

Bacterial leaf blight (BLB) is a destructive disease of rice which is caused by Xanthomonas oryzae pv. oryzae (Xoo.) [1]
Binadhan-8, BR11 and Binadhan-10 showed maximum reduction in plant height (11.43%, 11.47 and 18.22% subsequently) for BLB inoculated plants where IRBB21, IRBB65 and Kumragur showed 0% reduction from control condition (Table 3)
Binadhan-8, Binadhan-10 and BR-11 showed maximum reduction in effective tiller number (52.62%, 50.07% and 50.06% subsequently) for BLB inoculated plants (Table 5) where IRBB21, IRBB65 and Kumragur showed 0% reduction from control condition (Fig. 4)

Summary

Introduction

Bacterial leaf blight (BLB) is a destructive disease of rice which is caused by Xanthomonas oryzae pv. oryzae (Xoo.) [1]. Bacterial leaf blight (BLB) is a destructive disease of rice which is caused by Xanthomonas oryzae pv. This disease is mostly common in rice growing countries in Asia specially where there is irrigated and rainfed lowland [2]. At the early period of the infection, at the leaf tips lesions are observed. These lesions become yellowish and turn into irregular lesions with wavy margins covering the whole leaf blade with wavy margin at the later stage [4]. As a result of the infection immature and sterile and poor quality grains are produced [10]

Methods

Results

Conclusion