Ajay Kumar Gautam

Isolation of endophytic fungi from Cannabis sativa and study their antifungal potential

A systemic study of fungal endophytes associated with different plant parts of Cannabis sativa and their antifungal activity was investigated in the present study. A total of 281 plant segments, including 91 leaves, 93 stem and 97 petioles samples, were screened for the isolation of endophytic fungi. Totally, 212 (77.65%) segments were found colonised by different fungi. Highest colonisation frequency were observed in stem parts (84.94%), then leaves (82.41%) and lowest 59.79% in petiole. Total eight fungal genera belonging to 12 species were isolated. Aspergillus is recorded as the most frequently occurring genera with three species Aspergillus niger, Aspergillus flavus and Aspergillus nidulans followed by Penicillium with two species Penicillium chrysogenum and Penicillium citrinum, while Phoma, Rhizopus, Colletotrichum, Cladosporium and Curvularia with single species. The antifungal potential of A. niger and A. flavus – two most frequently isolated endophytic fungi – was evaluated against two common plant pathogen, Colletotrichum gloeosporioides and Curvularia lunata. Different plant and fungal extracts individually and in combinations showed variations in antifungal activity against both the pathogens. The primary results obtained on antifungal activity of endophytes show their possible role in plant defence mechanism but it is a preliminary approach and more extensive research is still required.

Diversity of fungal endophytes in some medicinal plants of Himachal Pradesh, India

Fungal endophytes were isolated from surface sterilised leaf segments of five medicinal plants collected from Mandi district, Himachal Pradesh, India. A total of 373 fungal strains belonging to 15 fungal genera and 18 species, Aspergillus niger, A. flavus, A. clavatus, A. variecolor, Penicillium chrsogenum, Alternaria alternata, Curvularia lunata, Haplosporium sp., Phoma sp., Nigrospora sp., Colletotrichum sp., Cladosporium sp., Stemphylium sp., Fusarium sp., Geotrichum sp., Phomopsis sp., Trichoderma sp., Rhizopus sp. and some sterile mycelium were isolated from all the plants. The relative frequency, isolation rate and colonisation rates of endophytes were used to study the endophytic diversity. The results showed that the highest colonisation rate (93.05%) was observed in Adhathoda vasica, while it was 91.66% in Ocimum sanctum, 85% in Viola odorata, 82.81% Cannabis sativa and lowest (61.11%) in Withania somnifera. Moreover, reading the richness and diversity of the endophytic fungi, the highest was obtained for O. sanctum, W. somnifera and C. sativa having eight species each, while lowest (6 and 4) was obtained from A. vasica and V. odorata, respectively. As the role of endophytic organisms in defensive mechanisms of plants is now well established, the present study is an important step to find new and interesting endophytes among the medicinal plants.

Colletotrichum gloeosporioides: Biology, Pathogenicity and Management in India

Colletotrichum gloeosporioides: Biology, Pathogenicity and Management in India Colletotrichum is one of the major plant pathogen causing anthracnose, a plant disease on variety of hosts from trees to grasses. In the present article we studied the taxonomy, biology and pathogenicity of Colletotrichum gloeosporioides and the taxonomical descriptions based on morphological, microscopic and molecular approach carried out in India are also discussed in detail. Biology of the pathogen with respect to its growth conditions and detailed symptoms of anthracnose are presented.

First report of Phoma betae on Aloe vera in India

Leaf spot disease of A. vera was observed in nurseries of Gwalior city afterthe post-rainy season. As the disease progressed, the tip of the leaf shrank, then dried and eventually broke. The causal agent was identified as Phoma betae A.B. Frank. This is the first report of leaf spot disease on Aloe vera caused by P. betae in India.

First report of anthracnose caused by Colletotrichum gloeosporioides on Boehravia diffusa in India

Leaf spot symptoms were observed on the leaves of Boehravia diffusa L. plants from different regions of Bilaspur, Himachal Pradesh, India. The symptoms initially appeared as a small light-pale coloured, circular spots enlarge gradually and ultimately leading to drying of the leaves. The disease was found to be caused by a fungus. The fungus was cultured on potato dextrose agar medium and identified as Colletotrichum gloeosporioides. According to the literature, this is thefirst report of anthracnose disease of B. diffusa caused by C. gloeosporioides in India.

First report of leaf spot disease caused by Phoma eupyrena Sacc. on Aloe vera from Madhya Pradesh, India

Abstract A leaf spot disease caused by Phoma eupyrena Sacc. on Aloe vera was reported from Madhya Pradesh, India. Disease symptoms were observed as irregular to elongated, sunken lesion on both leaf surfaces which later turns creamish brown with maroon margin. The fungal colonies were whitish or light pale to dark grey colour. The pycnidia were glabrous and solitary, papillate, and indistinctly uniostiolate averages 100–260 μm in diameter. Conidia were ellipsoidal, 4.5–7.5 × 2.5–3.75 μm in size, with two large guttules. To the best of our knowledge, this is the first report of P. eupyrena causing leaf spot disease on A. vera in India.

First Report of Nigrospora sphaerica Causing Leaf Spots on Celtis australis from Himachal Pradesh, India

Nigrospora sphaerica collected on living leaves of Celtis australis L. (Cannabaceae) from Himachal Pradesh, India is a new host record. Symptoms of the disease on leaves appeared in the form of small, circular to irregular, brown - coloured spots surrounded by a yellow zone. The fungus isolated was identified as Nigrospora sphaerica (Sacc.) E.W. Mason, on the basis of cultural and morphological characters. The fungus is described and illustrated.