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Sclerotium rolfsii (Sacc.) is the causal agent of stem-rot of groundnut plants which is an important damaging soil-borne root pathogen worldwide. Arbuscular mycorrhizal (AM) fungi ( Glomus fasciculatum ) and Trichoderma asperelloides have shown potential bio-control agent properties against several soil-borne plant pathogens. Interactions between G. fasciculatum , T. asperelloides and soil-borne pathogen S. rolfsii were investigated in this present pot culture experiment. The inoculation of G. fasciculatum and T. asperelloides reduced the severity of disease but their combinations were most effective in reducing harmful effects of S. rolfsii . The arbuscule percentage of AM fungi was affected by presence of T. asperelloides but chlorophyll content got increased by AM fungi or T. asperelloides treatments during S. rolfsii attack. The defense related physiological, biochemical and anti-oxidant activities observed in roots of groundnut plant significantly increased by single inoculation of AM fungi or Trichoderma . But, the combined inoculations of AM fungi and Trichoderma species showed the highest defense related activities. Moreover, single application of either AM fungi or Trichoderma species showed potential for the biocontrol of soil-borne plant pathogen but their combined application attributed most substantial inhibition in development of pathogen

The present experiment was conducted at University of Pune for biocontrol of soil-borne plant pathogen Sclerotium rolfsii by incorporating arbuscular mycorrhizal fungi (Glomus fasciculatum) and conventional system of cultivation with different spacing pattern (15 and 30 cm) in field. Both mycorrhizal inoculation and 30 cm spacing pattern significantly increased growth and yield as compared to control or 15 cm spacing pattern. The pathogenic mycorrhizal groundnut plants in 30 as well as 15 cm spacing pattern showed better growth in terms of plant height, leaf and pod number, fresh and dry weight of whole groundnut plant in comparison to non-mycorrhizal pathogenic ones and the plant growth was better in 30 spacing than 15 cm. The colonization by AM fungi in both spacing pattern was higher in absence of pathogen S. rolfsii. However, pathogen’s presence decreased the mycorrhizal colonization considerably in 30 and 15 cm. The disease severity and incidence were recorded to be lowered when inoculated with mycorrhiza in pathogenic groundnut plants as compared to non-mycorrhizal pathogenic ones in both spacing pattern and incidence and severity was significantly lower in 30 cm as compared to 15 cm. Therefore, it was observed from our results that for management of soil-borne pathogens inoculation of AM fungi and spacing patterns are necessary.

The fungal pathogen causes serious widespread losses to agricultural crops worldwide. Therefore, economy of countries may worsen especially of developing countries. In addition, harmful chemical pesticides which are being used today for increasing crop production creates very serious health hazardous problems to human beings and ecosystem as a whole. The antagonistic potential of Trichoderma species which has been long known to control various soil-borne fungal pathogens in biological way may be utilized. The faster growth rates with which it competes with fungal pathogen mainly brings upon their antagonistic characteristics. An investigation was carried out in laboratory condition towards biological efficacy of T. viride on potato dextrose agar (PDA) medium for the bio-control of soil-borne plant pathogens Sclerotium rolfsii and Macrophomina phaseolina in in-vitro condition. The dual culture technique was followed in which T. viride showed significant antifungal activities towards both the pathogens. T. viride significantly inhibited the mycelial radial growth of S. rolfsii by 75% and M. phaseolina by 71.42%. The results showed variable mycelial growth rate for all fungal isolates which was determined after 6 days of incubation in which T. viride showed minimum of 4.00 days to completely cover the petri-plates and S. rolfsii showed 4.33 days whereas M. phaseolina showed 6.33 days. Thus, T. viride showed encouraging results regarding their biopesticidal and biofungicidal potential against plant pathogens which may be endorsed to substitute harmful chemical supplements that exists in modern day agricultural practices.

Gmelina arborea Roxb. is medicinally and economically important tree species were selected for study. An experiment was conducted to determine the influence of arbuscular mycorrhizal (AM) fungus Glomus fasciculatum on salt stress tolerance of tree species Gmelina arborea. Mycorrhizal and nonmycorrhizal seedlings were treated with 100 mM and 200 mM concentration of NaCl. G. fasciculatum treated plant showed increase in fresh and dry weight, greater percentage of mycorrhizal colonization, higher accumulation of proline and chlorophyll content with increasing levels of salinity. G. fasciculatum colonization significantly increased tolerance of salinity, acid phosphatases, and Proline content and also antioxidant enzymes like peroxidase, catalase and superoxide dismutase at all levels of salinity treatments of Gmelina plants in comparison with non-mycorrhizal salinity treated plants. These results demonstrate that AM fungus (G. fasciculatum) is very effective in strengthening the tolerance of Gmelina arborea grown in arid and semi arid areas.

Catharanthus roseus L. (Apocynaceae), a valuable medicinal plant with potential therapeutic value was inoculated with AM fungi Glomus fasciculatum under three different phosphate conditions. Catharanthus roseus plants raised in presence of the AM fungi showed increased growth in terms of (shoot length, root length, leaf number, fresh weight and dry weight). Total chlorophyll content and phosphate content of the shoot was found to be significantly higher in AM inoculated plants as compared to non AM Catharanthus plants. The activities of phosphatase enzymes were found to be increased in AM inoculated plants as compared to non AM plants. Root colonization percent was significantly higher in AM inoculated plants at zero and at all three phosphate levels after 60, 90 and 120 days of AM inoculation, but decreased at third phosphate level after 120 days of AM inoculation. The study suggests that Catharanthus roseus is dependent on the mycorrhizal fungi to a large extent for its growth and survival and also shows the potential of AM fungi Glomus fasciculatum in increasing growth and biomass of Catharanthus roseus L.

Solanum melongena L. a medicinally and economically important crop plants were grown in polythene bags. The effect of mycorrhizal inoculation (Glomus mosseae) and increasing phosphate levels on the expression of the photosynthetic activity in terms of chlorophyll content. Antioxidant enzymes like peroxidase, polyphenol oxidase, root acid and alkaline phosphatase activity of Solanum melongena were evaluated. The experimental design was entirely at CRBD with eight treatments with three levels of phosphate (50,100,150 mg kg-1 of soil). Root colonization ranged from 50.33% to 67.33% . The activity of the studied antioxidant enzymes were found to be increased in arbuscular mycorrhizal (AM) Solanum plants. Root phosphatase activity was greater in 100 and 150 mg phosphate level in AM treated than non AM treated Solanum plants. Besides, only AM treated plants of Solanum reflected increase in total chlorophyll content as compared to non AM plants. This work suggests that the mycorrhiza helps Solanum plants to perform better in low and high phosphate level by enhancing antioxidant enzyme activity, acid and alkaline phosphatase activity and total chlorophyll content.

Arbuscular mycorrhizal (AM) fungi alleviating the adverse salt effects on growth was tested in bajra (Pennisetum glaucum). Towards this objective we analyzed the photosynthetic activity, proline, phosphatase activity and various antioxidant enzymes such as peroxidase, catalase and superoxide dismutase at 0, 100, 200 and 300 mM salinity levels in AM inoculated and non inoculated bajra plants. Total chlorophyll content was significantly higher in moderate salinity condition in AM fungus (Glomus fasciculatum) inoculated plants, which lead to increase in growth and nutrient uptake capacity of mycorrhizal plants. Antioxidant activity was either increased or decreased due to responses to different salinity stress conditions. Proline accumulation was induced by salt and it was more in shoot of non-AM inoculated plants, but in roots proline accumulation was higher in AM plants at all levels of salinity. This work suggests that the AM fungus helps bajra plants to perform better under moderate salinity levels by enhancing the antioxidant activity and proline accumulation as compared to non-mycorrhizal plants.

Potential of Arbuscular mycorrhizal (AM) fungi in alleviating adverse salt effects on growth was tested in garlic (Allium sativum L.). Towards this objective we analyzed the AM root colonization and the activities of various antioxidant enzymes like peroxidase, catalase, and superoxide dismutase at 0, 100, 200 and 300 mM salinity levels. The activities of all the antioxidant enzymes studied were found to be increased in AM garlic plants. Antioxidant activity was maximum in 100 and 200 mM NaCl (sodium chloride) in AM and non-AM plants. Proline accumulation was induced by salt levels and it was more in leaves as well as roots of AM plants as compared to non-AM plants, this indicating that mycorrhiza reduced salt injury. Growth parameters of garlic plants like leaf area, plant fresh and dry weight and antioxidant enzyme activities were higher at moderate salinity level. This work suggests that the mycorrhiza helps garlic plants to perform better under moderate salinity level by enhancing the antioxidant activity and proline content as compared to non-AM plants.

Present investigation deals with the beneficial effect of Arbuscular Mycorrhiza (AM) fungal species Glomus fasciculatum on growth performance of Allium sativum under field condition. In AM inoculated garlic plant showed significant increase in plant growth parameters like plant height, total biomass and bulb diameters, bulb weight, and yield. There was 21.10 % increment in yield of Allium bulb as compared to non AM inoculated garlic plant. Percentage of AM colonization occurred at all sampling and the colonization was higher during bulb initiation. Mycorrhiza inoculated garlic plant showed more alliin and allinase enzyme activity as compared to non inoculated garlic plant. The results reveal that mycorrhiza contribute to growth and development of garlic plant under field condition.