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A field experiment was conducted to study the effect of different land configuration and weed management treatments in greengram (Vigna radiata L.). The raised bed and ridge sown crop recorded significantly lower dry matter of weeds and significantly higher weed control efficiency (WCE) (78.4% and 78.1%, respectively ) than flat sown crop (68.5%). Raised bed sowing provided higher grain yield to the tune of 4.0 and 16.1% over ridge and flat sowing, respectively and gave significantly higher gross returns, net returns and B:C ratio than ridge and flat sowings. Application of pendimethalin @ 0.75 kg/ha as pre-emergence (PE) + imazethapyr @ 55 g/ha as post-emergence (POE) 15-20 days after sowing (DAS) and imazethapyr @ 55 g/ha (POE) 15-20 DAS recorded significantly lower dry matter of weeds and significantly higher WCE than pendimethalin @ 0.75 kg/ha (PE). The application of herbicides (pendimethalin as PE and imazethapyr as POE) had no adverse affect on symbiotic parameters. Pendimethalin @ 0.75 kg/ha (PE) + imazethapyr @ 55 g/ha 15-20 DAS provided significantly higher grain yield than the other treatments and gave the highest gross returns, net returns and B:C ratio. It can be concluded that sowing of greengram on raised bed land configuration along with application of pendimethalin @ 0.75 kg/ha (PE) + imazethapyr @ 55 g/ha 15-20 DAS was found to be effective for controlling weeds as well as improving the grain yield and providing higher net returns and B:C ratio.

The bacterium Bacillus thuringiensis widely used as bio-pesticide. The specific toxic activity to insects and another microbe(s) regarding the existing of crystals that have different morphologies, sizes, numbers and compositions, as Bt strains the crystals have more different proteins, which contain encoded Cry distinct genes. In this work we isolated 140 Bacillus thuringiensis isolates from 68 soil samples from 19 local areas in Punjab. Colonies examination was done by microscope for toxin production. Bacillus thuringiensis isolates showed a typical colony morphology, predominantly off white to creamish with irregular margins. Based on certain biochemical characterstics they were confirmed to be strains of Bacillus thuringiensis. Bt strains harboring crystalline inclusions that might have potential for use as bioinsecticidal agent was done under phase contrast microscope and Scanning electron microscope. Based on preliminary screening with phase contrast microscopy, its parasporal crystals have unsual shapes. Bt isolates were classified into bi-pyramidal crystals, pyramidal, cuboidal, amorphous and round crystal protein inclusions. After preliminary screening with phase contrast microscopy, Scanning electron microscopy confirmed the surface view of rod shaped bacterial cells found in chains and cluster arrangement. Bt isolated tended to have sub-terminal spores.