Cultural and morphological studies on Ponnampet leaf and neck blast isolates of Magnaporthe grisea (Herbert) barr on rice (Oryza sativa L.)

Abstract

The study was carried out to standardize the optimal growth, sporulation and production of perfect stage of pathogen on different media. Among different media used such as Potato dextrose Agar (PDA), Oat meal Agar, Ragi flour agar, yeast extract + 2% soluble starch, Host extract + 2% soluble sucrose agar, Potato dextrose agar + Biotin + Thiamine and Rice flour agar, Oat meal agar and potato dextrose agar was found to be best media for radial growth and sporulation of M. grisea. Maximum conidia length (9.46μm) and breadth (7.36μm) was recorded in Oat meal agar followed by Potato dextrose agar and least conidia length (6.15 μm) and breadth (5.11 μm) was recorded in ragi flour media after 20 days of inoculation. Conidial size varied in leaf and neck blast isolates, the maximum mean colony diameter of 88.00mm and 89.16mm in neck and leaf blast was recorded in Oat meal agar respectively. The maximum sporulation mean index was observed in Oat Meal agar of 3.15 μm in leaf and 3.20 μm in neck blast was recorded. The best growth of the pathogen was recorded at optimum pH range from 6.0 - 7.0 and temperature of 27oC. Therefore oat meal agar media was found to be best among all the media used for growth, sporulation, conidial size and colony characters of M. grisea.

Screening of cultural media for the growth of foliar fungal disease pathogens associated with aromatic rice

“…The effect of different media on the radial growth and colony description of Pyricularia oryzae is presented in Jagadeesh and Devaki (2020) [10] studied cultural morphology of 72 Magnaporthe oryzae isolates on OMA and PDA and observed significant growth. Teli et al (2016) [18] reported that PDA and OMA were found to be the best media for radial growth of Magnaporthe grisea isolated from Ponnampet. [21] recorded maximum growth and sporulation of the Bipolaris oryzae on corn meal agar medium followed by potato dextrose agar (PDA) and rice leaves agar.…”

Pathogenecity and in-vitro Assessment of Some Fungicides on the Mycelial Growth of Rice Blast Pathogen (Magnaporthe oryzae B.Cauch) in Jigawa State, Nigeria

“…The slants were allowed to incubate at 28 °C for 48 hours before being stored at 4 °C. The culture was refreshed every two months to maintain pure isolates of M. oryzae obtained through the hyphal tip isolation method (Al Noman and Shamsi, 2021;Teli et al, 2016).…”

“…A control group consisted of non-inoculated plants, while inoculated plants were protected with transparent nylon bags to maintain required air moisture, and symptoms' development was periodically monitored. Infected plants were subjected to re-isolation, and islate obtained were compared with the one used during inoculation for the confirmation of the pathogen identity (Hasan et al, 2016;Teli et al, 2016).…”