A review on threat of gray leaf spot disease of maize in Asia

Abstract

Biotic and biotic constraints are yield limiting factors in maize producing regions. Among these gray leaf spot is a yield limiting foliar disease of maize in high land regions of Asia. This review is done from related different national and international journals, thesis, books, research papers etc. The objectives of this review are to become familiar with genetics and inheritance, epidemiology, symptoms and disease management strategies etc. High relative humidity, temperature, minimum tillage and maize monoculture are important factors responsible for disease development. The sibling species of Cercospora zeae-maydis (Tehon and Daniels, 1925) Group I and Group II and Cercospora sorghai var. maydis (Chupp, 1954) are associated with this disease. Pathogens colonize in maize debris. Conidia are the source of inoculums for disease spread. Severe blighting of leaves reduces sugars, stalk lodging and causes premature death of plants resulting in yield losses of up to 100%. Disease management through cultural practices is provisional. The use of fungicides for emergencies is effective however; their prohibitive cost and detrimental effects on the environment are negative consequences. The inheritance of tolerance is quantitative with small additive effects. The introgression of resistant genes among the crosses of resistant germplasm enhances the resistance. The crosses of resistant and susceptible germplasm possess greater stability than the crosses of susceptible and resistant germplasm. The development of gray leaf spot tolerant populations through tolerance breeding principle is an economical and sustainable approach to manage the disease.Journal of Maize Research and Development (2015) 1(1):71-85DOI: http://dx.doi.org/10.5281/zenodo.34286

Diversity and occurrence of major diseases of vegetables and fruit crops during spring season at Aanbukhaireni rural municipality of Tanahun district, Nepal

“…Vegetables are grown in 286864 ha with the production of 3958230 mtand productivity of 13.79 t/ha in Nepal (MOALD, 2018). Pests and disease are destroying about one fifth of all crop production around the world and at least 10% of the global food production is lost through plant disease alone (FAO, 2000) mainly in West Africa and South Asia (Dhami et al, 2015). Diseases and pests are the major factors contributing to crop loss which hinders the income of rural families and global food security worldwide (Cerda, 2017).…”

USABILITY, STRENGTH AND PRACTICALITY OF THE UPCOMING HYSPIRI IN DETECTING MAIZE GRAY LEAFY SPOT IN RELATION TO SENTINEL-2 MSI, VENμS AND LANDSAT 8 OLI SPECTRAL BAND-SETTINGS

“…This maize disease is caused by a fungus known as Cercospora zeae-maydis which affects maize crops across all the phenological stages. According to Dhami et al (2015), Cercospora zeae-maydis is a polycyclic facultative pathogen or fungi, which survives as mycelium in the residues of infected maize crops after harvesting. The GSL disease typically starts in spring during the green-up phenological stage of maize plants when the conidia is transferred to new plants by wind and splashing rain water.…”

“…The conidia (spores) infect the maize crops through the stomatal openings of leaves. Approximately two to three weeks after colonizing the tissues of maize leaves, gray to tan lesions grow between the leaf veins giving them a narrow, rectangular appearance which are 5-70 mm long by 2-4 mm wide (Dhami et al 2015). These lesions ultimately sporulate, spread and coalesce covering the entire surface areas of leaves.…”

“…These lesions ultimately sporulate, spread and coalesce covering the entire surface areas of leaves. Subsequently, these lesions excessively reduce the level of sugar causing stalk lodging which ultimately results in premature death of maize crops as well as extreme yield losses of up to 100% (Dhami et al 2015). In this regard, GLS is widely recognized as the most significant yieldlimiting disease in maize crop production (Ward et al 1994, Geis 2014).…”

“…The emergence of this fungus was first noted in the samples collected in the state of Illions, United States of America by Tehon and Daniels (1925). GLS was and is still recognized as the most severe, destructive and yield limiting maize and corn disease especially when its incidences manifested at a large spatial extent in the maize growing states of America (Dhami et al 2015). In South Africa GLS was first recorded between 1988-89 in Grey town and in 1992 at Cedara in KwaZulu Natal Province (Gevers et al 1994, Ward et al 1994, Ward et al 1999.…”