Molecular and Morphological Characterization of Exserohilum turcicum (Passerini) Leonard and Suggs Causing Northern Corn Leaf Blight of Maize in Bihar

Abstract

Maize is considered the third most important cereal crop in Asia after rice and wheat. Many diseases affect this crop due to the cultivation of various hybrids. This research aimed to characterize the causative agent of northern corn leaf blight disease in Bihar, India, caused by Exserohilum turcicum (Passerini) Leonard and Suggs. Leaf samples were collected from infected fields in five maize growing districts of Bihar in 2020–2022. A total of 45 fungal isolates from 135 samples were examined for cultural, morphological, and molecular characteristics and were identified as E. turcicum. The isolates were grouped into four groups based on colony color, i.e., olivaceous brown, blackish brown, whitish black, and grayish, and into two groups based on regular and irregular margins. The conidial shapes were observed to be elongated and spindle-shaped with protruding hilum, with conidial septa ranging from 2–12. Similarly, conidial length varied from 52.94 μm to 144.12 μm. β-tubulin gene sequences analysis made it possible to verify the identities of fungal strains and the phylogenetic relationships of all isolates, which were clustered in the same clade. The β-tubulin gene sequences of all the isolates showed a high level of similarity (100%) with reference isolates from GenBank accession numbers KU670342.1, KU670344.1, KU670343.1, KU670341.1, and KU670340.1. The findings of this study will serve as a baseline for future studies and will help to minimize yield losses.

Epidemic development and management of common leaf rust (Puccinia sorghi Schwein) and turcicum leaf blight [Exserohilum turcicum (Pass.)] of maize (Zea mays L.) in eastern Ethiopia

“…Several studies conducted by Anwer et al. (2022) and Flora et al. (2023) also indicated that the usage of four genes offering major resistance genes to TLB has been identified and incorporated in many commercial hybrids to tackle the disease.…”

“…In this regard, CLR and TLB management through an integrated disease management that combines host resistance and chemical control strategies in a holistic way rather than using a single component strategy is the best option. It helps farmers improve their overall field management by reducing costs and improving production efficiency on an effective and sustainable basis (Anwer et al., 2022; Carson, 2016; El Khoury & Makkouk, 2010; Shiferaw et al., 2018; Zhang et al., 2022).…”

Variation in the morphology and effector profiles of Exserohilum turcicum isolates associated with the Northern Corn Leaf Blight of maize in Nigeria

“…The recovered isolates varied significantly in morphology including colony color, growth pattern, conidia structures, size, and RMG. Several colony colors of E. turcicum have been reported on PDA: from white to green-white, olivaceous gray to brown with black pigmentation [ 10 , 40 , 41 ]. The range of shades of colony morphology colors observed in the present study were similar to those previously reported.…”

Distribution and association of common leaf rust (Puccinia sorghi Schwein) and turcicum leaf blight [Exserohilum turcicum (Pass.)] of Maize (Zea mays L.) with biophysical factors in Eastern Ethiopia

“…It is one of the most versatile crops having wider adaptability under varied agroecological and climatic conditions. Globally, maize is known as “Queen of Cereals” as it is grown throughout the year due to its photo‐thermo insensitive character and the highest genetic yield potential among the cereals (Anwer et al., 2022; Navarro et al., 2021; Rehab et al., 2019; Romero, 2016).…”

“…In Ethiopia, maize is cultivated in most parts of the country for various purposes, including grain, feed, fodder, green cobs, baby corn, sweet corn, popcorn, and industrial products. In addition to staple food for human being and quality feed for animals, maize serves as a basic raw material as an ingredient to thousands of industrial products that includes starch, oil, protein, alcoholic beverages, food sweeteners, pharmaceutical, cosmetic, film, textile, gum, package, paper industries, and so on (Anwer et al., 2022; ATA, 2014; Gidi, 2023).…”