The present investigation is focused on exploring the possibilities of identifying biomolecules from the fruiting body of the medicinal mushroom Ganoderma lucidum against the mango anthracnose pathogen Colletotrichum gloeosporioides. The fruiting body (cap and stipe portion) of G. lucidum extracted with ethyl acetate solvent at a maximum inhibitory concentration of 1 percent exhibited the maximum mycelial growth inhibition of C. gloeosporioides with 70.10 percent and 40.77 percent, respectively. Furthermore, subjecting the ethyl acetate extracts from the cap portion of G. lucidum through thin layer chromatography (TLC) revealed the presence of two bands with Rf values of 0.38 and 0.35. The compounds eluted from band 1 recorded with the maximum mycelial growth inhibition of C. gloeosporioides by 53.77 percent followed by band 2 (46.33 percent) using an agar well diffusion test. Similarly, the analysis of ethyl acetate extracts from the cap portion of G. lucidum through Gas Chromatography-Mass spectroscopy (GC-MS) revealed the presence of the organoheterocyclic compound benzothiazole, as expressed in the highest peak area at 22.03 RT with the highest probability percentage (97%). Confirmation of the antifungal nature of benzothiazole was obtained by testing the standard sample of benzothiazole which showed a cent percent of inhibition on mycelial growth of C. gloeosporioides at 50 ppm minimum fungicidal concentration. Furthermore, benzothiazole caused abnormality in the mycelial structures, viz., distortion, shrinkage, clumping of mycelium, conidial malformation, and complete arrestment of conidial germination of C. gloeosporioides as observed through Scanning Electron Microscopy. The research on biomolecular extract of G. lucidum could be a novel and interesting concept for the possibility in suppression of plant pathogenic microbes in the natural field.
1 June 2020 in Pesticide Biochemistry and Physiology
Ganoderma lucidum is an important medicinal mushroom widely used in pharmaceuticals for their antiviral, antibacterial, antifungal, anticancer and immunoregulatory properties and also used in agriculture as an antiviral and antibacterial agent. Fourier Transform Infrared (FT-IR) spectroscopy is a tool widely used in the researches for the identification of organic compounds in the organism. In our study, we used FT-IR Spectroscopy for determination the chemical nature of Ganoderma lucidum, and their standards Squalene and Ganoderic acid A. In the FT-IR spectrum for the G. lucidum obtained in the region of 3782.69 cm-1 to 568.898 cm-1 the absorptions peak represents the alcohols, halogens, silicon and phosphorus groups present in the sample. In the squalene standard, ketones, amides, and guanidine, nitrile and azine stretches were found in the wavelength 1655-1550 cm-1. In the Ganoderic acid A sulfur compounds with weak stretching intensity were obtained in the wavelength 500-400 cm-1. We have concluded that FT-IR spectroscopy is an effective method to analyze the chemical nature of the organic groups present in the samples.
In this study, the volatilomes of naturally growing plant leaves were immobilized in a suitable substrate to enhance vapors’ diffusion in the soil to eradicate the Fusarium wilt pathogens in Tomato. Volatilomes produced by Mentha spicata leaves immobilized in vermiculite ball was found to be effective and exhibit 92.35 percent inhibition on the mycelial growth of Fusarium oxysporum f. sp. lycopersici (FOL). Moreover, the volatilomes of M. spicata immobilized vermiculite balls were tested based on the distance traveled by the diffused volatilomes from the ball and revealed that the volatilomes of M. spicata traveled up to 20 cm distance from the center of PVC (Polyvinly chloride) chamber showed maximum reduction in colony growth of FOL at 12th day after inoculation. Tomato plants inoculated with FOL revealed increased expressions of defense gene, pathogenesis related protein (PR1) with 2.63-fold after 72 h and the gene, transcription factor (WRKY) increased with 2.5-fold after 48 h on exposure to the volatilomes of M. spicata vermiculite balls. To the best of our knowledge, this is the first report on development of volatilomes based vermiculite ball formulations. This result indicated that the volatilomes of M. spicata are promising phyto-fumigants for management of Tomato Fusarial wilt.
Experiments were conducted to find out the effect of different casing soils viz., peat, clay loam soil, sandy soil, biogas slurry, FYM, cocopeat on the yield and yield attributing parameters of milky mushroom (Calocybe indica var.APK2). Among the different casing media, clay loam soil has given the maximum yield (390 g / bed containing 250 g of paddy straw substrate on dry weight basis recording 156% bio-efficiency) and more number of buttons (8.1 /bed) than other casing media. Analysis of physical, chemical and biological properties of clay loam soil revealed that it contained high pH 8.40. Cation Exchange Capacity (CEC) was high in clay loam (28.20 milliequivalents / 100 g of soil). Bulk density and particle density were comparatively higher in sand (1.67 g/cc) and clay loam soils (1.33 g/cc). The maximum pore space was recorded in clay loam soil (55.01 per cent) followed by peat (39.57 per cent) and sand (20.46 per cent). The WHC revelaed high per cent in peat soil (46.27) followed by clay loam soil (39.04). Hence, peat and clay loam soils required less water to maintain surface moisture and a delay in spraying did not lead to the total drying of bed surface. In addition, the population of Pseudomonas spp were found to be high in clay loam soil (34.0 cfu/ g of soil).