Which one of the following transmits grape fan and tobacco ring spot virus:

Correct option is D

Grape fanleaf virus (GFLV) and Tobacco ringspot virus (TRSV) are plant viruses that affect a wide range of crops and are primarily soil-borne. These viruses are not transmitted by insects or fungi but are instead vectored by nematodes.
�� Why Nematodes are the Correct Answer:
1. Grape Fanleaf Virus (GFLV):
· Vector: Xiphinema index, a type of dagger nematode
· Host: Primarily affects grapevines
· Symptoms: Deformed leaves, short internodes, poor fruit set, fan-like leaf structure
2. Tobacco Ringspot Virus (TRSV):
· Vector: Xiphinema americanum, another dagger nematode
· Host Range: Wide, including tobacco, soybean, peach, grape, and others
· Symptoms: Chlorotic ring spots, stunted growth, necrosis in leaves and roots
✴️ Mode of Transmission:
· Nematodes ingest and retain the virus particles in their feeding stylets.
· During feeding on healthy plant roots, they release the virus, thereby transmitting the infection.