Effect of Cucumber Mosaic Virus Inoculation at Successive Weekly Intervals on Growth and Yield of Pepper (Capsicum annuum) Plants. G. N. Agrios, Department of Plant Pathology, University of Massachusetts, Amherst 01003. M. E. Walker, Department of Plant Pathology, and D. N. Ferro, Department of Entomology, University of Massachusetts, Amherst 01003. Plant Dis. 69:52-55. Accepted for publication 18 June 1984. Copyright 1985 The American Phytopathological Society. DOI: 10.1094/PD-69-52.

Groups of pepper plants in the field were mechanically inoculated with cucumber mosaic virus (CMV) at successive weekly intervals from 22 June to 10 August. In early inoculations, inoculated leaves developed necrotic rings and oak-leaf-like patterns, whereas systemically infected leaves remained small and narrow and had a fine yellowish green mottle. In later inoculations, few inoculated leaves developed necrotic patterns and only leaves on some branches developed systemic symptoms of any kind. Most of the fruit of early-inoculated plants were small, slightly wrinkled, or bumpy and pale green; a few fruits had dark, depressed spots. The severity of foliar symptoms and the ratio of small, malformed fruit to normal fruit decreased as the date of inoculation was delayed. Plants inoculated in early growth stages were significantly shorter; produced markedly less top weight; and had significantly fewer and smaller leaves, fewer total fruit, and fewer marketable fruit than plants inoculated later in the season or plants remaining uninfected throughout the season. Plant growth and fruit yield improved in almost direct proportion to the lateness of inoculation of the plants with CMV.