Evaluation of False Smut Antagonistic Endophytic Bacterial Isolates on Rice Seed Parameters
M. Sathvika
Professor Jayashankar Telangana Agricultural University, Hyderabad, India.
D. Ladhalakshmi *
Indian Institute of Rice Research, Hyderabad, India.
M. Madhavi
Professor Jayashankar Telangana Agricultural University, Hyderabad, India.
P. C. Latha
Indian Institute of Rice Research, Hyderabad, India.
B. Pusphavathi
Professor Jayashankar Telangana Agricultural University, Hyderabad, India.
E. Dakshayini
Indian Institute of Rice Research, Hyderabad, India.
Padma Thakur
Indian Agricultural Research Institute, New Delhi, India.
J. S. Lore
Punjab Agricultural University, Ludhiana, India.
K. Basavaraj
Indian Institute of Rice Research, Hyderabad, India.
*Author to whom correspondence should be addressed.
Abstract
Aim: To evaluate the effects of bacterial isolates antagonistic to U. virens on rice seed parameters.
Study Design: Completely randomised design (CRD). Place and Duration of Study: Indian Institute of Rice Research, Hyderabad and Seed Research and Technology Centre, PJTAU, Hyderabad.
Methodology: Fourteen antagonistic endophytic bacterial isolates obtained from the tolerant genotypes RL-1516 and Vary Lava IRGC 386.1 were evaluated for seed treatment under in vitro conditions.
Results: Seed treatment with bacterial isolate EB-10 recorded the highest germination percentage of 88.76% compared with 81.67% in untreated seeds. Similarly, isolates EB-1 and EB-3 recorded the highest root length (6.76 cm) and shoot length (10.41 cm), respectively, compared with 3.13 cm and 6.49 cm in the control treatment. Rice seeds treated with isolate EB-4 recorded the maximum total seedling length of 16.99 cm, whereas untreated seeds recorded 9.62 cm. The highest seedling vigour index I (1430) was recorded following seed treatment with bacterial isolate EB-10, followed by EB-2, EB-3 and EB-4, with values of 1427, 1421 and 1409, respectively, compared with 782 in the control treatment. With respect to SVI II, the highest value of 25.47 was recorded following seed treatment with bacterial isolate EB-10, compared with 17.26 in the untreated control.
Conclusion: Seed treatment with the identified antagonistic bacterial isolates against the false smut pathogen U. virens improved seed germination percentage, root and shoot lengths, and seedling vigour indices I and II.
Keywords: Rice (Oryza sativa L.), rice false smut, Ustilaginoidea virens, endophytic bacteria, antagonistic isolates, seed biopriming, seed germination, root and shoot growth, seedling vigour index, biological control