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Seventeen species of nematophagous fungi were recorded, three species were endoparasitic and fourteen species were predacious fungi. Among the predacious fungi Arthrobotrys oligospora, Dactylaria brochopaga and Monacrosporium eudermatum were very frequent, whereas others were recorded at lower frequency. Twelve species of nematophagous fungi from compost as well as cow dung manure, 15 species from leaf litter and only eight species from agricultural soils were recorded. In general, substrate colonization by nematophagous fungi was higher in leaf litter, compost and cow dung manure. The agricultural soil amended with FYM (farm yard manure) recorded nine species of nematophagous fungi while unamended soil recorded only seven species. Thirteen species of nematophagous fungi were recorded from soils under banyan tree. Of all these fungi unidentified net-forming fungus, M. eudermatum, A. cladodes, D. brochopaga, S. hadra, A. oligospora and A. dactyloides had higher percentage of soil colonization. In soil collected under pipal tree only eight species were recorded, of which A. oligospora, A. cladode and an unidentified fungus were more predominant as their percentage colonized in soil samples was higher. Few studies have examined root galls as a substratum for colonization of nematophagous fungi. Of all the root gall samples, okra root galls recorded maximum colonization by predacious fungi. Maximum percentage of root gall colonization was recorded for M. eudermatum followed by A. oligospora and M. ellipsosporum. M. eudermatum was also most predominant colonizer of balsam, brinjal and rice root galls. [ABSTRACT FROM AUTHOR]

Seventeen species of nematophagous fungi were recorded, three species were endoparasitic and fourteen species were predacious fungi. Among the predacious fungi Arthrobotrys oligospora, Dactylaria brochopaga and Monacrosporium eudermatum were very frequent, whereas others were recorded at lower frequency. Twelve species of nematophagous fungi from compost as well as cow dung manure, 15 species from leaf litter and only eight species from agricultural soils were recorded. In general, substrate colonization by nematophagous fungi was higher in leaf litter, compost and cow dung manure. The agricultural soil amended with FYM (farm yard manure) recorded nine species of nematophagous fungi while unamended soil recorded only seven species. Thirteen species of nematophagous fungi were recorded from soils under banyan tree. Of all these fungi unidentified net-forming fungus, M. eudermatum, A. cladodes, D. brochopaga, S. hadra, A. oligospora and A. dactyloides had higher percentage of soil colonization. In soil collected under pipal tree only eight species were recorded, of which A. oligospora, A. cladode and an unidentified fungus were more predominant as their percentage colonized in soil samples was higher. Few studies have examined root galls as a substratum for colonization of nematophagous fungi. Of all the root gall samples, okra root galls recorded maximum colonization by predacious fungi. Maximum percentage of root gall colonization was recorded for M. eudermatum followed by A. oligospora and M. ellipsosporum. M. eudermatum was also most predominant colonizer of balsam, brinjal and rice root galls. [ABSTRACT FROM AUTHOR]

Dactylaria eudermata Drechsler is one of the important predaceous fungi occurring widely in different soils. The fungus produces hyphal bails and network compound in which nematodes are entangled. This hyphal nets as trapping structure which may be single dimensional to two or three dimensional and are formed through repeated hyphal anastomosis, which capture nematodes either through the adhesive material present on the surface of hyphal nets or due to physical entanglement. In the experiment it was observed that inflation of hyphal bails takes 30 to 50 minutes and capturing and killing the nematode by a single conidia in water takes 35-55 hours, were as time required for inflation of hyphal bails and real trapping and killing of a nematode in maize meal (MMA: water (1:10) medium) takes one minute and 30-50 hours respectively. [ABSTRACT FROM AUTHOR]

Onion is an important indispensable item in every kitchen as condiment and vegetable, hence commands an extensive internal market. The green leaves and immature and mature bulbs are eaten raw or used in preparation of vegetables. Among the various pests and diseases associated with onion, the root knot nematode (Meloidogyne incognita) had proved itself as an important limiting factor for successful cultivation of this crop. Recently root-knot nematode was observed to cause serious losses to green onion crop grown mostly in the field located near the Jamuna & Ganga river belt of Allahabad and the surrounding area in U.P. Differential host test was done to confirm the root knot disease in onion. The specific identity of the nematode was determined by cutting perineal pattern of the females and was confirmed as Meloidogyne incognita. [ABSTRACT FROM AUTHOR]

The variability in cultural characteristics and the virulence among three isolates of Fusarium oxysporum f. sp. ciceri causing vascular wilt in chickpea was studied under laboratory conditions. The three isolates (Foc-1, Foc-2 and Foc-3) did not show any significant difference in their mycelial dry weight production at any temperature regimes, pH level or the growth media tested. The radial growth on PDA also did not differ significantly in the three isolates. However, some quantitative differences were noted in colony characters and septations in macroconidia of these isolates. The isolate Foc-1 exhibited dull white, thin and flat hairy growth, spreading out like thread, Foc-2 showed a white fluffy colony with irregular aerial margin, while Foc-3 exhibited a pinkish white, slightly fluffy colony with regular margin. Conidia also differed with regard to septation. Three to six septa were present in Foc-2, while there were 2-3 in isolates Foc-1 and Foc-2. These isolates differed significantly with regard to their virulence on test varieties. Isolate Foc-1 was more virulent that Foc-2 or Foc-3 and produced abundant spores. [ABSTRACT FROM AUTHOR]

The antiviral agents namely Boerhaavia diffusa root extract and Clerodendron aculeatum leaf extract were found to be significantly effective in inducing systematic resistance against papaya ring spot virus in papaya. However, B. diffusa root extract showed more efficient properties as compared to C. aculeatum leaf extract. Maximum reduction in disease incidence (72.25% and 74.00%), maximum plant height (119.05 and 126.61 cm), number of fruit (20.04 and 24.05 plant-1) and fruit yield (22.86 and 25.93 kg plant-1) were observed with the application of B. diffusa root extract as seed treatment + nursery treatment + field treatment during 2005-2006 and 2006-2007 respectively. However, maximum disease incidence (78.79% and 70.56%) minimum plant height (87.46 and 92.40 cm), number of fruit (11.36 and 13.50 plant-1) and fruit yield (9.85 and 11.03 kg plant-1) were recorded with the application of B. diffusa root extract as seed treatment + nursery treatment + field treatment during both the years. [ABSTRACT FROM AUTHOR]

Lentil (Lens culinaris Medik.), the second most important rabi pulse crop of India, suffers heavy plant mortality due to wilt, root rot and collar rot at different stages of crop growth. Congenial soil temperature and moisture during early crop growth, winter rains and terminal drought favour invasion of the crop by many root-invading pathogens. The present study based on 265 samples from 76 districts of seven states of India revealed the involvement of 12 different fungi with the highest association of 30.8% of Fusarium oxysporum f. sp. lentis followed by 17.5 and 15.7% by Rhizoctonia bataticola and S. rolfsii, respectively. Percentage involvement of F. oxysporum f. sp. lentis and R. solani with lentil roots increased with the increase in crop age while that of R. bataticola decreased. S. rolfsii was found to be associated at maximum during the vegetative growth phase. It was further observed that F. oxysporum f. sp. lentis, R. bataticola. R. solani, S. rolfsii and Alternaria sp. were found universally associated at all moisture levels; F. oxysporum f. sp. lentis slightly increased with lower moisture availability while R. solani and R. bataticola were higher at high soil moisture. Other fungi found associated with wilted lentil roots were F. chlamydosporum, F. equisetii, Aspergillus, Penicillium, Helminthosporium, Rhizopus and Trichoderma species. The overall mean plant mortality was 3.5% up to 30 DAS, 7.7% between 30 and 90 DAS and 16.8% above 90 DAS. Similarly, it was 2% at low moisture, 18.5% at optimum moisture and 17.7% at high soil moisture. [ABSTRACT FROM AUTHOR]

A survey of 116 districts of nine lentil growing states covering 603 farmers' fields revealed a range of 0.7-9.3% mean plant mortality at reproductive stages in different lentil growing states of the country. The overall mean mortality was 6.3%. The main pathogens found associated with plant mortality at this stage were Fusarium oxysporum f. sp. lentis (62.0%), Rhizoctonia bataticola (25.2%) and Sclerotium rolfsii (9.8%). The minor involvement of 1.8% was that of F. solani, F. chlamydosporum. F. equisetii, and R. solani. For the first time a national scenario of lentil wilt-root rot incidence at the crucial reproductive stage and their associated pathogens is reported here. [ABSTRACT FROM AUTHOR]