Economic and Environmental Impact of Rice Blast Pathogen (Magnaporthe oryzae) Alleviation in the United States

Abstract

Rice blast (Magnaporthe oryzae) is a key concern in combating global food insecurity given the disease is responsible for approximately 30% of rice production losses globally—the equivalent of feeding 60 million people. These losses increase the global rice price and reduce consumer welfare and food security. Rice is the staple crop for more than half the world’s population so any reduction in rice blast would have substantial beneficial effects on consumer livelihoods. In 2012, researchers in the US began analyzing the feasibility of creating blast-resistant rice through cisgenic breeding. Correspondingly, our study evaluates the changes in producer, consumer, and environmental welfare, if all the rice produced in the Mid-South of the US were blast resistant through a process like cisgenics, using both international trade and environmental assessment modeling. Our results show that US rice producers would gain 69.34 million dollars annually and increase the rice supply to feed an additional one million consumers globally by eliminating blast from production in the Mid-South. These results suggest that blast alleviation could be even more significant in increasing global food security given that the US is a small rice producer by global standards and likely experiences lower losses from blast than other rice-producing countries because of its ongoing investment in production technology and management. Furthermore, results from our detailed life cycle assessment (LCA) show that producing blast-resistant rice has lower environmental (fossil fuel depletion, ecotoxicity, carcinogenics, eutrophication, acidification, global warming potential, and ozone depletion) impacts per unit of rice than non-blast resistant rice production. Our findings suggest that any reduction in blast via breeding will have significantly positive impacts on reducing global food insecurity through increased supply, as well as decreased price and environmental impacts in production.

Effect of Botanicals for Management of Leaf Blast and Enhancing Yield Traits in Rice

“…In recent years, improved chemical methods like use of organomercuric, organophosphorus and copper fungicides, antibiotics like Kasugamycin and Blasticidin S, site specific and systemic fungicides including melanin biosynthesis suppresser and plant activators and leaf extracts are utilized successfully for blast management [22]. Thus the researcher has to pay emphasis in producing blast-resistant rice with lower ecotoxicity, eutrophication, carcinogenics and acidification impact [4]. Several scientific study have identified plant species with more than 2400 bioactive compounds having insecticidal and anti-pathogenic properties, commonly referred as 'green pesticides', which are more compatible with environmental components compared to synthetic pesticides [23].…”

“…The pathogen, a holomorph of a complex of heterothallic Ascomycetes, is most damaging of rice diseases [3]. It causes high yield loss about 30% globally [4], and thus major threat to global food security [5]. In India, rice blast is a major production constraint in irrigated ecosystem [6] and under severe epiphytic conditions may result a loss of 70-90% [7].…”

Metabolomics as an Emerging Tool for the Study of Plant–Pathogen Interactions

“…Rice blast caused by Magnaporthe oryzae, which is the most economically serious disease in rice, is responsible for annual losses of more than 30% [172]. This fungal pathogen has a hemibiotrophic life style and infects its host at any developmental stage, causing damage to multiple tissues: Leaf, stem, node, or panicle [173].…”

Loss of premature stop codon in theWall-Associated Kinase 91(OsWAK91) gene confers sheath blight disease resistance in rice

“…In the United States, planting high-production rice varieties that are susceptible to SB, resulted in up to 50% yield losses 3 , in a severe breakout season. As a result, about 72% of the rice planting area in the United States is sprayed with fungicide that incurs unsustainable economic cost to the farmers 6 . The spraying may also pose severe ecological constraints on animals and microbiome that co-inhabit and/or frequently visit rice farms and fresh water bodies.…”