Twelve isolates of Trichoderma spp. isolated from tobacco rhizosphere were evaluated for their ability to produce chitinase and β-1,3-glucanase extracellular hydrolytic enzymes. Isolates ThJt1 and TvHt2, out of 12 isolates, produced maximum activities of chitinase and β-1,3-glucanase, respectively. In vitro production of chitinase and β-1,3-glucanase by isolates ThJt1 and TvHt2 was tested under different cultural conditions. The enzyme activities were significantly influenced by acidic pH and the optimum temperature was 30 °C. The chitin and cell walls of Sclerotium rolfsii, as carbon sources, supported the maximum and significantly higher chitinase activity by both isolates. The chitinase activity of isolate ThJt1 was suppressed significantly by fructose (80.28%), followed by glucose (77.42%), whereas the β-1,3-glucanase activity of ThJt1 and both enzymes of isolate TvHt2 were significantly suppressed by fructose, followed by sucrose. Ammonium nitrate as nitrogen source supported the maximum activity of chitinase in both isolates, whereas urea was a poor nitrogen source. Production of both enzymes by the isolates was significantly influenced by the cultural conditions. Thus, the isolates ThJt1 and TvHt2 showed higher levels of chitinase and β-1,3-glucanase activities and were capable of hydrolyzing the mycelium of S. rolfsii infecting tobacco. These organisms can be used therefore for assessment of their synergism in biomass production and biocontrol efficacy and for their field biocontrol ability against S. rolfsii and Pythium aphanidermatum infecting tobacco.

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Tobacco germplasm are of different 'types', with large numbers of accessions in each type. In order to effectively manage this tobacco germplasm information, a user-friendly menudriven software has been developed based on Visual Cþþ and MS-Access. The system allows the user to store, modify and update germplasm information as and when required, and represents a decision-making tool.

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Tobacco is a leading commercial crop valued for its leaf containing several important phyto-chemicals including nicotine. Conventionally, tobacco is used in the manufacture of cigarettes, bidis, scented chewing mixtures, cigars, cheroots, zarda, hookah, hookah tobacco paste, snuff, gutka, quiwam etc. Tobacco research in India, aimed at improving tobacco plant for higher leaf biomass with desirable leaf quality suitable for its conventional uses of smoking, chewing and snuffing. As a result of sustained research efforts, the productivity potential of tobacco increased to 3.0 t/ha in FCV and 4.0 t/ha in non-FCV with commensurate leaf quality so as to meet trade preferences. In view of the perceived health hazards associated with the traditional form of tobacco consumption, research efforts are intensified towards exploiting tobacco for its non-conventional and economically viable alternative uses.

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An assessment of soil fertility of Northern Light Soil area of FCV tobacco was carried out to study the status of soil macro and micronutrients. Soils of the study area are mostly moderately acidic in nature with low organic carbon and available nitrogen with a mean value of 0.29 % & 110 kg ha-1, respectively. Available phosphorus was high (88% samples) with a mean value of 92.6 kg ha-1. While the average available potassium content was 297 kg ha-1 with 48 % samples in medium class. Among available micronutrients, the available zinc content in 73 % of samples was very low – low (0.0 to 0.6 ppm).  Whereas the availability of copper in 25 % samples was very low to low as per the fertility class (0.0 - 0.30 ppm).  Available iron (18.8 -35.03 ppm) and manganese (17.03-21.5 ppm) contents were high in the region. Nutrient index of available nitrogen was 1.00 (Low) while, NI was 2.83 (High) & 2.36 (Medium) for available phosphorus and available potassium, respectively.

New advances in information technology led to the development of Expert Systems and their application in various sectors including farming. In India, agricultural production has been transformed into a multifaceted business enterprise. Indian agriculture to remain competitive needs the accumulation and integration of scientific knowledge, and information from many diverse sources.  Indian farmer often relies on agricultural specialists, advisors and agricultural research and development institutes for agricultural information for better decision making at the actual farm situation. Unfortunately, timely specialist assistance is not available when the farmer needs. Thus the situation demand for a ‘virtual expert’ who can give personalized expert advice to a large community of farmers, specific to their needs and aspirations considering various knowledge sources. The role of expert systems in tobacco sector and its applications in effective production and protection technologies have been discussed in this article. It is almost impossible for any human expert to consider every piece of available information before arriving at optimal decisions. To overcome this problem and provide precise information to the farmers, “expert systems” have been developed with a primary goal to make expertise available to clients and decision makers who need answers swiftly. The main aim is to deliver the required information and disseminate the up-to-date scientific knowledge in a readily accessible and easily understood form to the farmers. It is one of the most efficient extension tools to take the technology from scientists to the growers directly without any distortion of content which normally creeps in because of multiple agencies involved in conventional technology transfer systems. With this aim, ICAR-Central Tobacco Research Institute has developed a web-based expert system on tobacco using “Agridaksh”- an online tool developed by ICAR-Indian Agricultural Statistics Research Institute. This, online expert systems has the tremendous capacity to transfer location specific technologies and advice to the farmers with a greater precision