Evaluation of Bioagents and Biopesticides against Colletotrichum lindemuthianum and its Integrated Management in Common Bean

Abstract

Three bioagents (Trichoderma viride, T. harzianum and Gliocladium virens) and five biopesticides (Achook, Neemgold, Wannis, Spictaf and Neemazal) were evaluated under in vitro and in vivo conditions against Colletotrichum lindemuthianum. All the three antagonistic fungi caused significant inhibition of mycelial growth, maximum being with T. viride (69.21%) followed by T. harzianum (64.20%). Among the biopesticides tested at four concentrations, Wanis applied @ 1000 µl/ml caused maximum inhibition of 82.12 per cent followed by Spictaf (52.85%). T. viride and Wanis @ 1000 µl/ml were most effective in reducing the seed borne infection. Integration of bioagents with Bavistin showed that disease can be effectively managed with seed dressing either with Bavistin or biopesticide followed by foliar treatment with fungicide or biopesticide.

In vitro evaluation of some fungicides and bioagents against common bean anthracnose (Colletotrichum lindemuthianum Sacc. Magnus) Briosi Cavara

“…The highest growth of mycelia (3.4 cm) was measured from the control, whereas the least (0.67 cm) was from the dual culture containing T. viride (Table 1; Figure 3). This is similar to the works of Padder et al (2010) who, in India, recorded mycelia growth inhibition of 69.21 and 64.2% with T. viride and T. harzianum, respectively, against a local strain of C. lindemuthianum.…”

“…Siderophore production by different Trichoderma strains is documented (Heidrun et al, 1991). Padder et al (2010) suggested a hyphal interaction mechanism in which hyper parasitism along with the production of antibiotics and secondary metabolites like siderophores to have contributed to the inhibition of mycelial growth, and control of seed borne infection.…”

“…The use of Pseudomonas fluorescens and Trichoderma species are becoming increasingly common as an effective, economic and environment friendly approach and also effectively controlling many seed and soil borne pathogens including Colletotrichum. Padder et al (2010) Recent innovations showed that biological control of crop diseases is getting increased attention as an environ-mentally sound approach. But in Ethiopia, the method has received comparatively little attention.…”

Field Management of Anthracnose (<i>Colletotrichum lindemuthianum</i>) in Common Bean through Foliar Spray Fungicides and Seed Treatment Bioagents

“…Similarly, the co-formulation of metalaxyl and mancozeb (Mancolaxyl 72 WP), which resulted in satisfactory control of Colletotrichum coccodes on tomatoes, was found to be a good option to prevent fungicide resistance (Johnston, 1986). It has been reported that seed dressing or soil application of bioagents like Trichoderma viride, Trichoderma harzianum and Gliocladium virens caused significant inhibition of mycelial growth of C. lindemuthianum, thereby effectively controlled the seed borne infection and increased the seed germination of common bean (Padder et al, 2010). Extracellular metabolites like siderophores, antibiotics, lytic enzymes and volatile compounds produced by rhizobacteria (Pseudomonas fluorescens and Bacillus cepacia) have also been reported to effectively reduce lesions and damages caused by C. lindemuthianum on bean plants (Hernandez et al, 2004).…”

“…Necrotic lesions can also be observed on the upper leaf surface and on the petioles. On the pods, the presence of medium lesions are evident but also some small and large lesions generally with sporulation and that cover approximately 10% of the pod's surface area may be found and 9= more than 25% of the leaf surface area covered with large coalescing and generally necrotic lesions resulting in defoliation (Sharma, 2010).…”