The combined effect of the application of a biocontrol agent Paecilomyces lilacinus, with various practices for the control of root-knot nematodes

The effectiveness of a formulated product containing spores of the naturally occurring fungus Paecilomyces lilacinus, strain 251, was evaluated against root-knot nematodes in pot and greenhouse experiments. Decrease of second-stage juveniles hatching from eggs was recorded by using the bio-nematicide at a dose of 4 kg ha(-1), while a further decrease was recorded by doubling the dose. However, the mortality rate decreased by increasing the inoculum level. Application of P. lilacinus and Bacillus firmus, singly or together in pot experiments, provided effective control of second-stage juveniles, eggs or egg masses of root-knot nematodes. In a greenhouse experiment, the bio-nematicide was evaluated for its potential to control root-knot nematodes either as a stand-alone method or in combination with soil solarization. Soil was solarized for 15 d and the bio-nematicide was applied just after the removal of the plastic sheet. Soil solarization for 15 d either alone or combined with the use of P. lilacinus did not provide satisfactory control of root-knot nematodes. The use of oxamyl, which was applied 2 weeks before and during transplanting, gave results similar to the commercial product containing P. lilacinus but superior to soil solarization. (C) 2007 Elsevier Ltd. All rights reserved.

Studies on the genus Paecilomyces in China V. Taifanglania gen. nov for some monophialidic species

A rare monophialidic fungus, Taifanglania hechuanensis gen. & sp. nov., was isolated from soil oil the banks of Jialin River, Hechuan, Chongqing City during a survey of soil-borne filamentous fungi from different phytogeographical areas in China. It is described and illustrated in this paper. A further eight monophialidic species of Paecilomyces are transferred to the genus. Diagnosis features of the new genus are white, grey, straw yellow or brown to black colonies on Czapek agar. Conidiophores are always absent or simple. Phialides are solitary, consisting of a cylindrical or ellipsoidal swollen basal portion, tapering into a thin neck, directly arising on vegetative hyphae or prophialides, sometimes consisting of a whorl of 2 to 3 phialides oil simple conidiophores. Conidia arc one-celled, hyaline, smooth-walled, subglobose, ellipsoidal or fusiform, having or no the connective between conidia and being thermotolerant. The new species is characterized by pale yellow to grey-yellow colonies, solitary phialides with ail ellipsoidal or fusiform basal portion that arise directly from the vegetative hyphae, big conidia (3.1-)3.9-8.7 x ( 1.7-)2.1-4.7(-5.1) mu m with the connective, and thermotolerant growth. A molecular study based oil the nucleotidic sequences of the SSU rDNA and ITS regions support the status of T. hechuanensis as a new species and Taifanglania as a new genus.