Question

please explain in simple details.

what is magnaporthe oryzae?

is it a fungus? where does it come from?

how does it affect plants?

how does it impact the enrvironmet?

how does the disease cycle start?

Answer 1

What is magnaporthe oryzae ? Is it a fungus ?

Magnaporthe oryzae is a hemibiotrophic fungal pathogen that causes rice blast, a serious disease affecting rice. Magnaporthe oryzae is a fungus.

Where it comes from ? How does the disease cycle start ?

Rice blast disease is favored by moderate temperatures (24 degree Celsius) and periods of high moisture that are 12 hours or longer, conditions whichis readily attainable in flooded rice fields. The soruces of primary inoculum of the spores of Magnaporthe oryzae consists of grasses, volunteer plants, infested refuse and infested seeds on the soil surface after planting. The fungus can also sporulate on the dead or dying coleoptiles of plants grown by infested seeds. These spores produce the initial infections on rice plants (generally through leaf tissue).

How does it affect plants ?

Rice blast disease affects almost all the parts of the plant like leaf, stem, nodes, panicle and root. Lesions are observed on these parts of the plants. It also affects the reproduction of the rice plant by causing the host to produce fewer seeds. This is generally caused by the disease preventing maturation of the actual grain. This fungus infection affects the production of rice crop worldwide.

How does it impact the environment ?

Rice blast disease persists wherever rice is grown in the world. The production of rice is affected which creates stress on nature, as an organism will always find an alternative to survive. If not rice, the organism will search for some other crop which creates a stress on nature as it has to produce the other crop in more amount. Also excess use of fertilizers to fight with this disease will affect the environment badly.