Abstract-Tridax procumbens is a common weed plant belonging to the family Asteraceae. The leaf juice has antiseptic, insecticidal and parasiticidal properties. The present work is based on developing a protocol for the callus induction in Tridax procumbens from various explants like leaf, internodes and shoot apical buds. The sterilized explants were inoculated in MS media containing various combination of auxins such as 2, 4, dichlorophenoxy acetic acid (2, 4-D) and naphthalene acetic acid (NAA) and cytokinins such as kinetin and 6 benzyl amino purine (BAP). Leaf and apical bud explants showed early and profuse callus induction whereas internodal explants showed comparatively delayed but profuse callus induction. Leaf and apical bud explants showed maximum response in terms of callus by using MS media with the combination 2, 4-D 0.5mg/lit and BAP 0.5mg/lit which was followed by 2, 4-D 0.5mg/lit and KIN 0.5mg/lit, 2, 4 -D 0.5mg/lit and BAP+KIN 0.5 mg/lit, NAA 0.5mg/lit and BAP 0.5mg/lit, NAA 2mg/lit and BAP 0.5mg/lit respectively. Whereas internodal explants showed maximum callus induction by using a hormonal concentration of 2mg/lit 2,4, D and 0.5mg/lit BAP. In vitro generated callus can be used as a source for the isolation of secondary metabolites from Tridax plant.

Stevia rebaudiana  Stevia rebaudiana  Stevia started simultaneously 7 days after sowing. Differencesin the germination and survival percent were recorded in the first generation.High dose of Gamma irradiation increased delay in days of germinationand maturity. The germination and survival percent decreased with increasingdosage of gamma radiations. The data on days to germination, germinationpercentage and survival percentage, indicated that low dose ofgamma radiation had very less effect on germination of Stevia seeds. It wasnoticed that up to 5 to 10 KR dose there was no statistically significant differencein seed germination as compared to control. However, germinationpercentage was significantly affected by higher doses of gamma rays.seeds. The seeds were given 5, 10, 15, 20, 25 and 30 KR(Kiloradians) exposures. Gamma irradiated seeds were treated with sodiumazide and colchicines solution for 4 h separately. Germination in control andtreated seeds of Bert. produces sweet steviol glycosides in the leaves. Currentinvestigation was carried out to study effects of gamma irradiations on

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The medicinal plant Stevia rebaudiana (Asteraceae family) produces sweetsteviol glycosides in the leaves which can be used as a natural alternative toartificial sweetener. The propagation by seeds or other methods is not viabledue to the low rate of seed germination. The present study was focused oninduction and maintenance of callus from leaf explants of Stevia by usingdifferent concentrations of 2, 4 dichlorophenoxy acetic acid . Surface sterilizedleaf explants were inoculated in MS medium with vitamins, sucrose (30g l –1), agar (0.8% w/v) and supplemented with various concentrations of 2, 4‐D (0.5, 1.0, 1.5, 2.0, 2.5 and 3 mg l –1). Medium supplemented with 2.5 mg l–12, 4 Ã¢â‚¬ÂD showed best callus induction. Leaf extracts in different solvent systemswere screened for antimicrobial activity against some Gram Ã¢â‚¬Âpositiveand Gram Ã¢â‚¬Ânegative bacteria by disc diffusion method. The chloroform andmethanol extract of leaves exhibited a concentration dependent antibacterialinhibition.