Abstract
Alternaria blight [Alternaria brassicae (Berk.) Sacc.] is one of the most widespread and harmful maladies of rapeseed-mustard, causing yield loss up to 47 per cent. Meteorological parameters especially temperature, relative humidity and bright sunshine hours play major role in the development of Alternaria blight disease. Infection by the pathogen is highly influenced by meteorological conditions. A well-tested model based on meteorological variables is an efficient tool for forewarning this disease. Epidemiology of Alternaria blight of brassicas was investigated based on long term data during 2003-2018 crop seasons on the disease severity and meteorological variables, which was validated with data for two subsequent years. During this study, meteorological variable-based regression model of forewarning was developed for maximum severity (%) of Alternaria blight on leaves and pods for three locations viz., New Delhi, Hisar (Haryana) and Mohanpur (West Bengal)] in India. Validation of the forewarning models for maximum severity (%) of Alternaria blight proved the efficiency of the targeted forecasts.
Highlights
Alternaria blight [Alternaria brassicae (Berk.) Sacc.] is one of the most widespread and harmful maladies of rapeseed-mustard, causing yield loss up to 47 per cent
While recommending management strategies under Jorhat conditions, Talukdar et al (2017) reported that early sowing of rapeseed could effectively help in reducing the severity of Alternaria blight
Different meteorological variables viz., minimum and maximum temperature and afternoon relative humidity were identified as critical factors, which significantly affected the development of Alternaria blight of rapeseed-mustard
Summary
Alternaria blight [Alternaria brassicae (Berk.) Sacc.] is one of the most widespread and harmful maladies of rapeseed-mustard, causing yield loss up to 47 per cent. Meteorological variable-based regression model of forewarning was developed for maximum severity (%) of Alternaria blight on leaves and pods for three locations viz., New Delhi, Hisar (Haryana) and Mohanpur (West Bengal)] in India. Initiation of the disease on pods occurs between 67 and 142 DAS, highest being 99 DAS Meteorological conditions such as temperature, relative humidity (RH), rainfall and bright sunshine hours are exceptionally important factors in the severity of Alternaria blight on rapeseed-mustard. The present multi-locational study was undertaken to develop meteorological variable dependent epidemiological models for quantitative and early forewarning in Alternaria blight of rapeseed- mustard. Meteorological parameters-based forewarning models were developed for maximum severity (%) of disease on leaves and pods and validation of the forewarning models was undertaken to prove the targeted forecasts in last two years or the subsequent crop seasons. With the combined effects of weather variables, weather indices were developed as weighted accumulations of product of weather variable (taking two at a time), weights being correlation coefficients between variable to forecast and product of weather variables considered in respective weeks (Yadav et al, 2016; Chattopadhyay et al, 2021)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
