Question

Question 15 2 pts When pathogenic fungi are found growing on the roots of grape vines, grape farmers sometimes respond by covering the ground around their vines with plastic sheeting and pumping a gaseous fungicide into the soil. The most important concern of grape farmers who engage in this practice should be that the O lichens growing on the vines' branches are not harmed. O fungicide might also kill mycorrhizae. O sheeting is transparent so that photosynthesis can continue. fungicide might also kill the native yeasts residing on the surfaces of the grapes.

Answer 1

Question 15. Fungicide may also kill micorrhizae.

Micorrhizae is the term used to describe the symbiotic relationship between mycorrhizal fungi and a plants root system. First the spore of the mycorrhyzal fungi germinate in the soil and make their way to the nearest roots. The roots are then colonized by the fungi and the mycorrhiza are established. The fungi penetrate the root and create an internal network of fungal structures inside the root cells . Then the plant and the mycorrhiza exchange sugars and nutrients. Finally the hyphae continue to develop outside the roots forming an extended network of fine filaments which can cover upto 700 times more soil area than the plant own roots. This secondary root system draws in extra beneficial nutrients and water, supporting a plant for its entire life.

It is found that in viticulture, the hyphal network increase the supply of nutrients and increase 14% of grape production. Many of the fungicides are compatable with micorrhiza as even if the external hyphae is destroyed the fungal part inside the roots can grow again into hyphae after few weeks of fungicidal application . But some fungicides can suppress the growth of mycorrhiza for ever. So there is a possibility that the pumping of gaseous fungicide into the soil might kill the micorrhiza growth and can affect the grape production.