CHARACTERISTICS OF SOME RHIZOCTONIA SPP FROM SOUTH-AUSTRALIAN PLANT NURSERIES

Forty-nine Rhizoctonia isolates were obtained from nursery plants, pot ting mix, vegetable seedlings and bedding plants in South Australia. O f these isolates, 75% were binucleate Rhizoctonia and 25 % were multin ucleate. Anastomosis tests showed that all of the multinucleate isolat es were either Rhizoctonia solani AG-2-1 or AG-4 and that the binuclea te Rhizoctonia belonged to either AG-F, AG-I, AG-K and CAG-5 or to fou r other groups of isolates which did not anastomose with the known iso lates tested. Teleomorphs of 14 isolates were induced and were identif ied as Thanatephorus cucumeris, Ceratobasidium cornigerum, C. pseudoco rnigerum and two unknown species Ceratobasidium. Extracellular pectic enzyme patterns were not useful in determining likely anastomosis grou ps for the binucleate Rhizoctonia.