نقش بقاياي گياهي ، خاك و كودهاي حيواني روي تراكم جمعيت قارچهاي گروه ASPERGILLUS FLAVUS و ASPERGILLUS NIGER در باغهاي پسته استان كرمان

THE ROLE OF PLANT DEBRIS, SOIL AND MANURE ON POPULATION DENSITY OF ASPERGILLUS FLAVUS AND ASPERGILLUS NIGER GROUPS IN PISTACHIO ORCHARDS OF KERMAN PROVINCE

Population density of Aspergillus flavus, fungi that may produce aflatoxin and Aspergillus niger groups were studied during 1998- 2002 in pistachio litter, soil and three kinds of manures in Kennan province, including Kennan, Sirjan, Rafsanjan and Zarand areas. The result indicated that A, niger group was recovered more frequently than A. flavus group (p= 0.5%).Soil dilution method in AFPA and CZ media were used to isolate the fungi from different substrates. The population density of A.flavus and A. niger was respectively zero to 4.65x10 6 and 0 - 5.2x106 in pistachio refuse and 0- 6.82x10 3 and 0- 5.44x104in leaf litter. The frequency of recovery of Aspergillus species in pistachio green, hull and leaf was 85 and 81%(cfu/g) respectively. The average population density in sheep, cow and poultry manures were respectively 0 - 4.2x10 50 -1.7x104 and 0 - 8.7x104 for A.flavus and 0 -1.7x10 4 0-3x10 4 and 0 -1.25x10 3 for A.niger groups.The frequency of recovery of A. flavus and A. niger in sheep, cow and poultry manures were 64, 75, 54 and 51, 43 and 50% respectively.Aspergillus species were soil borne in pistachio growing areas and their populations influenced by frequency and time of irrigation.