Infectiousness of Cercospora arachidicola Hori and Phaeoisariopsis personata (Berk. and Curt.) Von Arx after defoliation of infected peanut leaves
1990
Paningbatan, R.A. | Opina, O.S. (Visayas State Coll. of Agriculture, Baybay, Leyte (Philippines))
The sporulation of Cercospora arachidicola Hori and Phaeoisariopsis personata (Berk. and Curt.) Von Arx, respectively, the cause of early and late leafspots of peanut, after defoliation of infected peanut leaflets was quantified over time as influenced by soil moisture. Also, the viability of conidia produced on lesions of air-dried leaves were determined at various storage temperature. Both pathogens on lesions of defoliated leaflets either on the surface or buried 3-inch deep in the dry sandy loam soil remained infectious with declining sporulation capacity within 50 days; whereas in the wet soil, infectiousness was lost after 20 and 10 days when leaflets were on the surface and buried, respectively. At 0 deg C., conidia of both pathogens survived for 10 weeks but viability was lost at 5 and 4 weeks of storage at 30 deg C and 5 deg C, respectively. Within 15-25 deg C, conidia of P. personata significantly survived longer than those of C. arachidicola which may explain why in a previous survey of peanut fields all over the Philippines, late leafspot is relatively a predominant disease.
显示更多 [+] 显示较少 [-]