| Popis: |
Potato virus Y (PVY) is an economically important disease agent in potatoes with worldwide distribution. It is mainly transmitted vegetatively by tubers and between plants by an aphid vector. PVY management is primarily through reducing viral inoculum in seed tubers and other sources and controlling transmission by aphids. Seed certification programs are designed to comprehensively test and restrict levels of PVY within a region, enforcing low levels of PVY in marketed seed lots and allowing growers informed choice to plant low-PVY crops. Sanitation techniques on the farm can also reduce volunteer, weed, and neighboring field sources of PVY. Major techniques to reduce aphid-mediated PVY spread include mineral oil foliar sprays, especially combined with insecticides. Spray timing is important, starting early after first plants emerge, continuing weekly through season to vine-kill, with additional sprays during rapid growth and periods of aphid abundance. Other practices for PVY reduction include avoiding mechanical transmission by field equipment, planting crop borders or intercropping as a barrier or sink for PVY, breeding PVY-resistant potato varieties, and roguing symptomatic plants from fields. Major remaining challenges in combatting PVY are management complacency, proliferation of PVY strains circumventing resistance and roguing, and informal trade of untested potatoes. |
