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Milky mushroom (Calocybe indica) also known as tropical mushroom or summer mushroom has significant attributes of milky white colour with high nutritive value and long shelf life. The yield performance of milky mushrooms again depends on the secretion of lignocellulolytic enzymes that further influence the colonization of mycelium on the substrates. In the present study, organic supplements viz. cakes of cotton, groundnut, sesamum, coconut cake, neem cake, powdered moth bean, red gram, horse gram, green gram, soya bean, lab-lab, maize, rice bran and wheat bran amended at 1% and 5% concentration induced profuse mycelial growth and enhanced ligninolytic enzyme secretion by Calocybe indica under in vitro conditions. The results revealed that wheat bran and red gram supplements at 5 % concentration in PDA medium were found to influence the mycelial growth on the 7th day (68.67 mm and 62.33 mm respectively). Similarly, both wheat bran and red gram supplements at 5 % in liquid medium supported increase in the biomass production of C. indica on the 15th day (1.83 and 1.40 g) followed by horse gram. The influence of organic supplements on the induction of lignocellulolytic activity showed that the maximum cellulase and xylanase activity (1.7 U/min/g and 0.835 U/min/g respectively) and laccase activity (1.6 U/min/g) were noticed in the substrate supplemented with wheat bran followed by horse gram (1.3 U/min/g) at 5% concentration under solid-state fermentation. However, the lignin peroxidase activity was maximum (0.59 U/min/g) in combination with wheat bran (2.5%) and red gram (2.5%) and manganese peroxidase activity was maximum in wheat bran supplement (0.3 U/min/g) at 5% concentration. It is inferred that amending organic supplements viz. wheat bran, horse gram and red gram to substrates enhance the mycelial growth, biomass production and lignocellulolytic enzyme secretion of C. indica and offers scope for yield improvement.

Aim: The present study was formulated with an aim to evaluate different locally available residues from trees such as mixed saw dust, saw dust of coconut wood log, coconut leaf stalks/petiole, coconut coir waste, saw dust of areca nut wood log for cultivation of medicinal mushroom Ganoderma lucidum. Methodology: Locally available agro residues viz., mixed saw dust, saw dust of coconut wood log, chopped coconut leaf stalks/petiole, coconut coir waste, saw dust of areca nut wood log were mixed with 20% wheat bran as supplement and packed in bags at 175 g/bag, autoclaved and aseptically inoculated with grain spawn of G. lucidum and provided with different temperature and humidity conditions for production of fruiting bodies. Results: Among the substrates, coconut wood log saw dust supported early spawn run within 46.5 days and early pinhead production on day 54 followed by pinhead expansion in 62.3 days and first harvest within 70.5 days. The average number of fruiting bodies were also higher (5.75 numbers/bag) with an average weight of 13.5 g/fruiting body that gave significantly higher yield of 77.5 g/175 g substrate with bioefficiency of 44.3% in a cropping cycle of 100.5 days compared to other substrates. Interpretation: The results show that coconut wood log saw dust substrate offers great scope for artificial cultivation of G. lucidum with a significant bioefficiency of 44.3 %.

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.

Bud blight disease caused by groundnut bud necrosis virus (GBNV) is a serious constraint in the cultivation of agricultural crops such as legumes, tomato, chilies, potato, cotton etc. Owing to the significant damage caused by GBNV, an attempt was made to identify suitable organic antiviral agents through molecular modelling of the nucleocapsid Coat Protein of GBNV; molecular docking and molecular dynamics that disclosed the interaction of the ligands viz., Squalene and Ganoderic acid-A with coat protein of GBNV. In vitro inhibitory effect of Squalene and Ganoderic acid-A was examined in comparison with different concentrations, against GBNV in cowpea plants under glasshouse condition. The different concentrations of Squalene (50, 100, 150, 250 and 500 ppm) tested in vitro resulted in reduction of lesion numbers (1.69 cm2) as well as reduced virus titre in co-inoculation spray. The present study suggests the antiviral activity of Squalene by effectively fitting into binding site of coat protein of GBNV with favourable hydrophilic as well as strong hydrophobic interactions thereby challenging and blocking the binding of viral replication RNA with coat protein and propagation. The present organic antiviral molecules will be helpful in development of suitable eco-friendly formulations to mitigate GBNV infection disease in plants.

Tomato is an important vegetable crop which is severely affected by Groundnut bud necrosis virus (GBNV). Until now effective antiviral agents have not been reported for the management of necrosis disease caused by GBNV. Therefore, a study was undertaken to manage the necrosis disease caused by GBNV using culture filtrate of basidiomycetous fungi viz., Coprinopsis cinerea, Ganoderma lucidum and Lentinula edodes. In vitro studies were conducted in the indicator host cowpea and primary host tomato in glasshouse under insect proof condition; co-inoculation spraying of culture filtrate of Ganoderma lucidum at 0.1% concentration reduced the lesion numbers and inhibited the virus population build-up when compared to inoculated control in the indicator host cowpea upto 77.83%. DAC-ELISA test was performed to quantify the virus titre, indicated reduced virus titre in co- inoculation spray of culture filtrate of G. lucidum treated cowpea with OD value 0.17 ± 0.01 at 405 nm and in tomato plants 0.14 ± 0.01 respectively. The viral copy numbers were quantified by qPCR. About 2.0 × 101 viral copy numbers were observed in tomato plants treated with G. lucidum (co-inoculation) which was lesser than untreated inoculated control plants (2.4 × 108). In order to identify the antiviral properties of G. lucidum, GCMS analysis was carried out and we found the triterpenoid compound Squalene. This is the first study to analyse and confirm the antiviral activity of G. lucidum against a plant virus.