CHICKPEA WILT INCITED BY PEA STREAK CARLAVIRUS

Pea streak carlavirus (PSV) incited a widespread wilting and yellowing disease of chickpea (Cicer arietinum) in commercial and experimental plantings in the Palouse region of eastern Washington and northern Ida ho. Incidence of PSV usually ranged from 0.5 to 5%. Experimental host ranges of several Palouse PSV isolates were confined to the Fabaceae a nd one species of Amaranthaceae. Systemic necrosis developed in chickp ea, lentil (Lens culinaris), pea (Pisum sativum), fenugreek (Trigonell a foenum-graecum), and faba bean (Vicia faba), while alfalfa (Medicago sativa), white sweet clover (Melilotus alba), and hairy vetch (Vicia villosa subsp. villosa) were symptomless carriers of PSV. The virus pr oduced local lesions without systemic spread in Gomphrena globosa, Sen na obtusifolia, and S. occidentalis. At Central Ferry, Washington, the virus was isolated from naturally infected Medicago lupulina, M. sati va, and Melilotus alba, but not from 40 other wild species. Pea streak virus was isolated from 93% of alfalfa fields sampled, and virus inci dence ranged from 0 to 44%, making alfalfa the primary reservoir and o verwintering host of PSV in the Palouse region. All 55 cultivated chic kpea germ plasm accessions tested, as well as eight wild annual specie s of Cicer, were susceptible to PSV in inoculation tests. Four wild pe rennial species of Cicer were resistant to the virus. Seed yields of t hree chickpea lines were reduced 97-99% by inoculation at prebloom and 16-50% by inoculation at full bloom. Seed quality was also adversely affected. No seed transmission of PSV was detected in chickpea, lentil , M. lupulina, or M. sativa. The pea aphid (Acyrthosiphon pisum) trans mitted PSV in a nonpersistent manner.