Ritesh Kumar

New report of Neozygites sp. infecting red spider mite Tetranychus urticae infesting French bean from Eastern Plateau and Hill region, India

An anamorphic entomopathogenic fungus Neozygites sp. belonging to the Family Neozygitaceae was found infecting the tetranychid mites Tetranychus urticae Koch (Acari: Tetranychidae) of French bean (Phaseolus vulgaris L.) for the first time in Eastern Plateau and Hill region of India in the month of October 2011. The report of entomopathogenic fungus could be of help in managing acaricide resistant mites.

New report of Hirsutella sp. infecting mango hopper Idioscopus clypealis from Chotanagpur Plateau, India

An entomopathogenic fungus belonging to the genus Hirsutella was found infecting the mango hopper, Idioscopus clypealis (Lethierry) (Hemiptera: Cicadellidae), for the first time in India in September 2011. The report of a natural control agent of mango hopper during the off season has special significance because its outbreak depends upon its residual hibernating population.

Substrate Decomposing Fungi of Mushroom and their Management by Some Common Fungicides

Four substrate decomposing fungi (Trichoderma harzianum, Papulaspora byssina, Sclerotium rolfsii and Penicillium chrysogenum) were isolated from the Pleurotus florida mushroom bed which were prevailing continuously in the growing season which cause severe yield losses of mushrooms in Eastern Plateau and Hill Region (EP&HR). An in vitro experiment was designed to see the effect of some common fungicides viz., Carbendazim, Mancozeb and Ridomil-MZ which are widely used in the mushroom cultivation were tested on 0.05, 0.075 and 0.1% concentrations to see the effect on substrate decomposing fungi and mycelial proliferation of P. florida. It was found that the Redomil-MZ showed strong antifungal efficacy against S. rolfsii, P. byssina and P. florida which inhibited 100% of the mycelial growth at very low concentration (0.05%). Moreover, Carbendazim was also showing strong antifungal properties which inhibited >80% growth of the T. harzianum, P. byssina at the same concentration (0.05%). But P. florida, S. rolfsii and P. chrysogenum were unaffected against all the test concentrations. Mancozeb inhibits 100% growth of P. chrysogenum at all the test concentrations but the growth of P. byssina >80 growth was arrested at 0.05% but the mycelial growth of P. florida was also inhibited up to 30% at 0.1% concentration.

New report of Lasiodiplodia theobromae causing Jatropha decline in Eastern Plateau and Hill region of India

Lasiodiplodia theobromae (Pat.) Griffon & Maubl. causing Jatropha (Jatropha curcas L.) decline was reported for the first time from Eastern Plateau and Hill region of India. The symptoms of the disease initially observed are yellowing, drooping and shedding of leaves and later as necrotic lesions on stem. Vascular discolouration was also observed when the infected portion of stem was split open. The disease-causing pathogen was isolated and identified on the basis of its colony morphology, conidial and pycnidial characteristics.

Torrubiella pruinosa, a teliomorph of an entomopathogenic fungus Hirsutella versicolor of mango hopper (Idioscopus clypealis) from India

Torrubeilla pruinosa, a teliomorph of an anamorphic entomopathogenic fungus Hirsutella versicolor on mango hopper (Idioscopus clypealis) was observed. On the infected mango hopper, tiny pin head signs of ascomata were observed. Ascomata of T. pruinosa is pale brown or tawny brown, crowded, immersed in stroma, wall dark golden brown, 260–320 × 230–260 μm, asci clavate, hyaline and thin walled. The ascospores of T. pruinosa are fusiform, distoseptate with a faint tint of pigmentation, 17.5–25.0 × 5.0–7.5 μm. The anamorph stage of H. versicolor fungal hyphae is hyaline, septate and profusely branched, and conidiogenous (phialides) cells are hyaline, pear-shaped and smooth-walled with single or double sterigmata and rarely, multiple sterigmata. Each sterigmata bears single conidia which are hyaline, oval to pear-shaped.