Photosynthesis and predisposition of plants to infection with certain viruses.

摘要: The effects on susceptibility to infection with certain viruses of subjecting plants various periods darkness or reduced illumination before and after inoculation were tested. hosts used a tobacco necrosis virus in French bean tobacco; tomato aucuba mosaic bushy stunt Nicotiana glutinosa. All the virus-host combinations give necrotic local lesions, was measured by lesion counts. Susceptibility consistently increased pre-inoculation treatments host plants, whereas post-inoculation had relatively little effect, but most often decreased susceptibility. Short dark produced similar responses longer shade, different varied their response to, tolerance of, darkness. maximum number lesions usually obtained kept for only 24 hr. inoculation, increasing time up 5 days. It is suggested that successful establishment occurs two stages, first which affected by. accumulation photosynthetic products. Whether these products confer resistance cell turgor reacting specifically particles unknown, sap from light possesses no greater virus-inhibiting power than dark.