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The cotton bollwormHelicoverpa armigera(Hübner) is the most destructive pest of cotton, tomato and chickpea in Iran. In this study, the lethal and sublethal effects of thiacloprid were evaluated against cotton bollworm under laboratory condition at 26 ± 1 °C, 70 ± 5% RH and a photoperiod of 16:8 (L:D). Bioassay experiments were conducted on first larval instars by mixing the insecticide dilutions with artificial diet. The LC50value of thiacloprid was 329 mg a.i./l. Sublethal effects of LC30concentration of thiacloprid was studied on biological parameters. In the study of sublethal effects, thiacloprid at LC30concentration significantly increased larval and pupal developmental times and reduced adults longevity compared with control but showed no significant effects on fecundity of cotton bollworm. Sublethal effects of thiacloprid also significantly reduced pupal weight compared with control. In general, sublethal effects studies showed that thiacloprid had adverse effects on biological parameters of the pest. Thus, our data suggest that thiacloprid had moderate potential against cotton bollworm. [ABSTRACT FROM AUTHOR]

Fusarium yellow disease of chickpea (Cicer arietinum), caused by the vascular wilt pathogenFusarium oxysporum, is a major production constraint in chickpea-growing regions of Iran. Fifteen isolates ofF. oxysporumwere classified on the basis of vegetative compatibility (the ability to form heterokaryons). Vegetative compatibility was assessed by pairingnitmutants. The isolates were assigned to three vegetative compatibility groups (VCGs): VCG1, VCG2, and VCG3 with 5, 3, and 7 members, respectively. These isolates were also characterized by virulence assay. On the basis of disease severity on chickpea seedlings, they were divided into three groups: highly virulent (HV), moderately virulent (MV) and weakly virulent (WV). Twelve arbitrary decamer primers were tested on the fungal isolates by polymerase chain reaction. Random amplified polymorphic DNA (RAPD) analysis indicated considerable genetic variation among these isolates. Comparison of the results of VCG tests and the virulence assay indicated that all seven HV isolates belong to a single vegetative compatibility group (VCG3), and all three WV isolates are placed in VCG1. There was no relationship between RAPD groups and the other two characteristics of IranianF. oxysporumisolates. [ABSTRACT FROM AUTHOR]

Chickpea blight caused by Didymella rabiei is the most important disease of chickpea in Kermanshah province in west of Iran. The pathogen survives in infected chickpea debris and seeds. The telemorph develops on overwintering chickpea debris and can play a roll on distribution and survival of the pathogen. Pseudothecial development of Didymella rabiei on naturally infected chickpea debris was investigated in some major growing areas of chickpea production in west of Iran. In this regard chickpea debris, stems and pods of naturally infected by D. rabiei were collected at harvest time. They were placed on soil surface of some fields in different regions of the province in September during 2003 to 2005. In 2003 D. rabiei did not develop on chickpea debris but in 2004 mature pseudothecia and pycnidia of D. rabiei formed on chickpea debris in all locations. Differentiation of pseudothecia initials happened in November, 30 to 45 days after placement of debris on the soil surface. Ascospore maturation occurred in early March. Discharge of ascospores occurred in late March and continued by mid-May. Completely empty pseudothecia were observed in mid-June. [ABSTRACT FROM AUTHOR]

Focuses on the first report of Faba bean necrotic yellows virus (FBNYV), Chickpea chlorotic dwarf virus (CpCDV) and Soybean dwarf virus (SbDV) naturally infecting chickpea and lentil in Iran. Detection of FBNYV and Bean leaf roll virus in all five provinces surveyed; Provinces where CpCDV and SbDV were detected; Overall incidence of virus.