Effects of Cultivar, Planting Period, and Fungicide Usage on Rice Blast Infection Levels and Crop Yield

Abstract

Studies were separately conducted to determine the effects of cultivar, planting date, and fungicide usage on rice blast disease, caused by Pyricularia grisea (Cooke) Sacc. [= Magnaporthe grisea (Hebert) Barr] in Kecamatan Manggala, South Sulawesi Indonesia. The four rice varieties were IR-66, Cisantana, Cigeulis, and Filipin. The results showed that IR-66 was moderately resistant to leaf and neck blast, with the lowest percentage unfilled grains per panicle. Cisantana reacted moderately resistant to leaf blast, but moderately susceptible to neck blast. Cigeulis was moderately susceptible to leaf and neck blast, while Filipin showed a highly susceptible reaction to both leaf and neck blast, and a 31% plant population death due to the blast disease. With respect to planting dates (February 4, March 22, and May 16), plants transplanted in March had the highest leaf blast severity, neck blast incidence, and the lowest yield. Seven fungicides (four are recommended for use in rice in Indonesia: flusilazol, difenoconazole, difenokonazole+propikonazole, and carbendazim (6.2%)+mancozeb (73.8%)) and three generally used ones (menefoxam (4%)+mancozeb (64%), chlorothalonyl, and metalaxyl) which were evaluated against the rice blast disease, showed the recommended fungicides for use in rice to be more effective in suppressing blast and protecting yield, compared to the other fungicides.

Susceptibility of novel Italian rice varieties to panicle blast under field conditions

“…The differences between years were less marked, 261 with significant differences only between 2015 (12.66) and 2018 (11.52), but not with 2016 262 Nonetheless, the PB incidence at 6 WAT in 2018 was lower compared to 2015 and 2016. This 297 evidence disagrees with several studies, which report a higher final incidence associated with early 298 symptoms (Filippi and Prabhu 1997;Long et al 2001;Nasruddin and Amin 2012). However, the 299 environmental conditions in our study were very different from those explored in the cited 300 literature, and other findings suggest that in Italy leaf blast does not consistently correlate with PB 301 (Biloni and Lorenzi 2002).…”

An Overview of Rice QTLs Associated with Disease Resistance to Three Major Rice Diseases: Blast, Sheath Blight, and Bacterial Panicle Blight

“…Among the biotic stresses of rice [18,19], blast disease that is caused by the fungus Magnaporthe oryzae can decrease rice yield up to 70-80% in most rice growing areas in the world [20,21]. Actually, this disease affects a large proportion of cultivated rice, which can feed 60 million people per year and makes a loss over 70 billion dollars of economic value [22].…”

Rice Blast Disease (Magnaporthe oryzae): A Menace to Rice Production and Humanity

“…Rice production across the globe is affected by various biotic and abiotic stresses [5]. Rice blast disease is recognized as the most dangerous and destructive fungal disease among the biotic factors affecting rice production [6,7]. This disease has been reported to cause up to 70 to 80% grain loss whereas some authors report yield losses of 100% i.e total loss during the epidemic growing season [8][9][10].…”