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The silver nanoparticles (AgNPs) synthesized using hot water neen leaf extract (NLF) as reducing and stabilizing agent are reported and evaluated for antibacterial activity against chilli seed borne pathogens. The effect of extract concentration, contact time, pH and temperature on the reaction rate and the shape of the Ag nanoparticles were investigated. The data revealed that the rate of formation of the nanosilver size decreased significantly in the basic medium with different concentration (1 mM, 5 mM and 10 mM). Synthesized was characterized by UV-vis spectroscopy, X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The nanoparticle synthesis using different concentration of silver nitrate and 5 mM was getting nano sized silver particles AgNPs. The silver nanoparticles were with an average size of 55 to 350 nm and mostly rod shape. The antifungal activity of synthesized AgNPs was observed in seed health test and different concentration of silver NPs (750 mg, 1000 mg and 1250 mg) were used for seed health test. The AgNPs at 750 mg concentration significantly inhibited the seed borne pothogens. Thus AgNPs showed broad spectrum antifungal activity at lower concentration and may be a good alternative therapeutic approach in future.

Investigations were undertaken to study the physiological effectiveness of different ornamental succulents under tropical condition. Six species of succulents were evaluated under four different growing environments. Results showed that the performance of succulents grown under conservatory house condition was found to be performed well and ideal with respect to chlorophyll, carotenoids, relative water content and photosynthetic rate than other growing environments. The succulent species viz ., Haworthia limifolia, Monadenium lugardiae and Aloe juvenna were the most suitable species for growing under conservatory house condition due to its high nocturnal CO 2 uptake and cell sap acidification which possess CAM metabolism. CAM involves nocturnal CO 2 uptake and fixation by cytosolic phosphoenolpyruvate carboxylase into malic acid that is stored in the vacuole causing nocturnal cell sap acidification. During the subsequent light period, malic acid is released from the vacuole in the form of malate that is then decarboxylated leading to deacidification of cell sap, formation of pyruvate or phosphoenolpyruvate and liberation of CO 2 . Repeated acidification and deacidification cycles represent a characteristic physiological feature of CAM metabolism in succulents which is best suited for xeric environment and possess high photosynthetic efficiency.