Macrophomina phaseolina (Tassi goid) is a pathogen that causes Charcoal rot of mungbean resulting in to a great economic loss. In the present study effect of Ocimum sanctum L., Calotropis procera (Ait.) Ait. f. and Astragalous tribuloides Delile extract on the survival of Macrophomina phaseolina was studied. The variety of different extracts of Ocimum sanctum L., Calotropis procera (Ait.) Ait.f and Astragalous tribuloides Delile brings various biochemical changes under suitable condition. The alkaline extract of Ocimum sanctum L., shows the maximum growth of Macrophomina phaseolina, Acidic extract of Calotropis procera (Ait.) Ait. f. and alcoholic extract of Astragalous tribuloides Delile show maximum growth of Macrophomina phaseolina. It showed that Macrophomina phaseolina was less reactive in these extract. On the other hand, aqueous acidic extract of Ocimum sanctum L., alkaline extract of Calotropis procera (Ait) Ait. f. and acidic extract of Astragalous tribuloides Delile showed minimum growth of Macrophomina Phaseolina. It indicated that Macrophomina phaseolina was more reactive in these plant extract.

Antifungal activity of medicinal plants leaf extracts on growth of Macrophomina  phaseolina

<div>Investigations on the insecticidal activity of Red algal seaweeds viz., Gracilaria corticata J. Agardh, Liagora ceranoides J. V. Lamouroux, and Asparagopsis taxiformis (Delile) collected from Rameswaram coastal ecosystem against Leaf eating caterpillar, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) &nbsp;was conducted in the Department of Entomology, Faculty of Agriculture, Annamalai University, India during 2016-2018. Powdered seaweeds at 1, 3, 5, 7, 10 and 20 per cent concentrations were investigated for their toxicity and insect growth regulator activity aganist S.litura under CRD in free choice test with three replications along with control. Observations showed that, larval mortality noticed after 36 hours after treatment in G. corticata treatments and even 100 per cent mortality was achieved at 72 hours of treatment, whereas the other two seaweeds exhibited larval mortality only after 72 hours of treatment and extended further to pupation and adult emergence. Among the concentrations the higher doses (20 and 10%) exhibited the maximum larval mortality (100%) while the maximum doses of other two seaweeds powder treatments did not, exhibited cent per cent larval mortality at any point of time and even pupated and gone for adult emergence also. The results displayed that, all the seaweed had exhibited larval mortality and their inhibiting substance inside needs to be investigated.</div>


<div>Investigations on the Larvicidal Effect of Red Algal Seaweeds of Rameswaram Coast Against Tobacco Caterpillar <em>Spodoptera Litura</em> (Fab.)</div>


Antifungal activity of medicinal plants leaf extracts on growth of Macrophomina phaseolina

Investigations on the Larvicidal Effect of Red Algal Seaweeds of Rameswaram Coast Against Tobacco Caterpillar Spodoptera Litura (Fab.)