Integrated management of late blight of potato

Abstract

Late blight of potato is the major biotic constraint responsible for reduction in yield and quality of the pota-to crop. Globally, late blight is managed through application of multiple fungicidal chemical sprays affecting both human health and environment. Now a days, methods of biological control are gaining importance as these are non-toxic and also environment friendly. However, Phytophthora infestans multiplies very fast; therefore, biological con-trol method alone is not a viable option to manage late blight. Hence, integration of both methods is essential. Eleven treatments consisting of biocontrol agents and fungicides were evaluated against the late bight in three consecu-tive seasons (2011-12, 2012-13, 2013-14) at ICAR-CPRIC, Modipuram. Meerut. The results revealed that the treat-ments ( T1 to T10) are effective for managing the disease up to certain level; however, lowest average disease se-verity (27.89%) was recorded in treatment when Bacillus subtilis (B5-0.25%) + Trichoderma viride (TV-0.7%) was applied before disease appearance followed by cymoxanil8+mancozeb 64%WP (0.3%) at onset of late blight and one more spray of B5+ TV after seven days. The next best treatment was application of B5+ TV before appearance of disease followed by metalaxyl 8+mancozeb 64%WP (0.25%) at onset of late blight and one more spray of B5+ TV against control (average disease severity 91.94%) with higher yield also except the treatment of three spray of mancozeb 75% WP (0.2%). These treatments could be integrated in farmer practices.

Management of Late Blight of Potato

“…The antagonist Bacillus subtilis B5 was found effective in inhibiting the growth of P. infestans [81]. The efficacy of bacterial and fungal antagonist found effective as lowest average disease severity (27.89%) was recorded in treatment when Bacillus subtilis (B5-0.25%) + Trichoderma viride (TV-0.7%) was applied before disease appearance followed by cymoxanil 8% + mancozeb 64%WP (0.3%) at onset of late blight and one more spray of B5 + TV after 7 days [82]. The different isolates of Trichoderma were evaluated against P. infestans and found that Trichoderma isolates HNA 14 was most effective under both laboratory and field conditions and showed mycoparasitism against P. infestans when observed under scanning electron microscope [83], whereas T. koningiopsis and T. asperellum were effective against P. infestans under both laboratory and field conditions [84].…”

Evaluation of Cytrol and Revus Fungicides Against Late Blight of Potato

“…The findings were in contrast to the present studies where revus was found to be the least effective one in controlling the pathogen growth. Lal et al (2017) applied mancozeb 64% WP and metalaxyl at the same time before the symptom's appearance of late blight of potato followed by the onset of disease after seven days. There was a distinct difference between the spray utilization, prior to the appearance of disease symptoms that significantly affected the pathogen incidence on potato crop.…”

The Use of Bio‐Agents for Management of Potato Diseases

“…The antagonist Bacillus subtilis B5 was found effective in inhibiting the growth of P. infestans [20]. Integrated management of late blight, using two sprays of Bacillus subtilis+ Trichoderma viride and one spray of fungicides, at the onset of disease is found to be effective for managing late blight of potato [21]. Rhamnolipid is a class of glycolipids, which is produced by bacteria.…”