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Severe leaf spot disease was observed on Aloe vera plants in the winters of 2011 and 2012 during a survey of various nurseries of Gwalior, India. Irregular, sunken, dark creamish brown spots having reddish brown margin were noticed on both surfaces of the leaves. The causal organism was consistently isolated from symptomatic leaves on potato dextrose agar media (PDA). A total 59 isolates of fungi were recovered from diseased A. vera leaves, and 37 isolates were identified as belonging to the genus Fusarium. On the basis of morphological characteristics and internal transcribed spacer (ITS) region of rDNA amplified using the primers ITS4/ITS5 the pathogen was identified as Fusarium proliferatum (Matsushima) Nirenberg and pathogenicity of the isolate was confirmed by using Koch’s postulates. To the best of our knowledge, this is the first report of leaf spot disease caused by Fusarium proliferatum on A. vera plants in India.

Avasthi S, GautamAK, Bhadauria R. 2015. Occurrence of leaf spot diseases on Aloe vera (L.) Burm.f. caused by Curvulariaspecies from Madhya Pradesh, India. Biodiversitas 16: 79-83. During 2010-2011, occurrence of leaf spot diseases was observed on Aloevera plants grown in various nurseries of Gwalior, Madhya Pradesh, India. The typical disease symptoms were observed on the abaxialsurface, tips and spiny margins of leaves. Disease spots were sunken, dry, necrotic, dark maroon to dark brown in color. On the basis ofmorphological and microscopic characteristics of the fungus, two species of Curvularia i.e. Curvularia lunata and Curvularia ovoidea,were found to be associated with the leaf spot diseases. Koch’s postulate was applied to confirm the causal organisms of the diseases.According to the literature, this is the first report of leaf spot disease on A. vera caused by Curvularia lunata from Madhya Pradesh, andthe first report of Curvularia ovoidea from India.Key words: Aloe vera, Curvularia lunata, Curvularia ovoidea, leaf spot, India

Sixty samples, categorized on the basis of manufacturers, were analyzed during the study. A total of 16 fungal species, belonging to 7 different genera, were isolated from the collected samples. Aspergillus was recorded as the most dominant genus with 9 species, namely, A. niger, A. carbonarius, A. luchuensis, A. fumigatus, A. flavus, A. nidulans, A. terreus, A. ochraceous, and A. wentii. A. niger was the most predominant species with frequency of occurrence of 63.33%. A large variation in fungal load and diversity was observed among the samples of different manufacturing categories. The percent moisture content and pH of samples were directly related to the extent of contamination. Samples with low pH and high moisture content were more contaminated. The higher incidence of A. niger (74.36%) was observed among the triphala powder of all manufacturing categories. Detection of ochratoxin producing fungi in triphala powder may pose a serious risk of ochratoxin production. Thus, there is an urgent need to enforce quality standards and regulation to minimize the fungal contamination to the globally expectable limit.

Evaluation of thirty one core collections of Ocimum sanctum L. synonyms O. tenuiflorum L. collected from different ecological regions representing contrasting environment of India was carried out. All the collections were grown under sub-tropical region of Jammu, India. Study revealed wide range of variability in quantitive and qualitative attributes of oil. Essential oil content ranged between 0.16% ± 0.01% - 0.55% ± 0.08% showing the presence of fifteen constituents. Methyl eugenol (1.54% - 93.16%) and Eugenol (0.06% - 70.41%), were the major constituent. The other major constituent of the oil was β-Caryophyllene (4.60% - 33.77%) which was detected in almost all the collections. Borneol, Copane, α Caryophyllene were other constituents detected in almost all the accessions. α selinene was detected in traces in only three accessions (OS-01, OS-03, OS-50) and β-selinene was detected in four accessions (OS-01, OS-03, OS-50, OS-72. Accession OS-70 collected from Patna, showed distinct chemical profile having β-Elemene (32.81%), β-Cary- ophyllene (16.37%), Germacrene-D (18.05%), β-Ocimene (17.69%) and Copane (5.738%). Being distinct in oil profiling, Patna collection was designated as distinct chemotype. Collections OS-50 from Gwalior from Central India and OS-59 from Rajkot Western India have been identified as methyl eugenol (93.16%) and eugenol (70.41%) rich geno- types. The data collected provided useful information with respect to composition of essential oil among core collection evaluated representing various agro-climatic zones.

In leprosy, lepromatous form of the disease is more severe and results from suppression of T cell response. T regulatory cells which suppress T cell response has been found in higher frequency in blood and at the site of infection in leprosy. Therefore, present study was carried out to evaluate the role of Mycobacterium leprae antigens whole cell sonicate (WCS) and especially phenolic glycolipid-1 (PGL-1), which is known for its suppressive nature, in the induction of T regulatory cells expansion in peripheral blood of leprosy patients. For this purpose peripheral blood mononuclear cells (PBMCs) of different category of leprosy patients and healthy controls were stimulated with M. leprae antigens in vitro and percentage of T regulatory cells was determined by flow cytometry. We found higher frequency of T regulatory cells in PBMCs of untreated borderline lepromatous/lepromatous leprosy (BL/LL) patients. Further, PBMCs of untreated BL/LL patients also showed higher percentage of T regs after stimulation with PGL-1. Antigen mediated expansion of T regulatory cells was also supported by results of Carboxy fluorescein succinimidyl ester (CFSE) proliferation assay. None of the antigen induced T regs expansion in healthy controls, untreated tuberculoid/borderline tuberculoid (TT/BT) leprosy patients and treated leprosy patients. Therefore it is suggested that increased frequency of T regs in BL/LL patients may be due to the induction of T regs expansion mediated by PGL-1 of M. leprae and this high percentage of T regs resulted in T cell suppression in lepromatous disease.