For thousands of years, rivers have been used as a source of water, transport, hydropower and as a means for disposal of waste. There are numerous threats that loom over the future of rivers, pollution being the chief among them. The increase in pollution is leading to the destruction of the habitat of various species inhabiting the waterways. Increasing competition for water among various sectors, like agriculture, industry, domestic consumption, energy generation and others, is depleting this precious natural resource which much attention in the current scenario. Waste water from manufacturing or chemical processes in industries contributes significantly to water pollution. The effects of water pollution are devastating to living systems. Polluted water is unsuitable for drinking, recreation, agriculture and industry. It diminishes the aesthetic quality of rivers. More seriously, contaminated water destroys aquatic life and reduces its reproductive ability. Eventually, it is a hazard to human health. The alarming rate at which river systems is being destroyed is a deeply disturbing trend, especially when these are the natural habitats of most species. There is a need for assessment of pollution stress on the river ecosystem. The ability to cope with environmental stress affects the physiological system in terms of energy of the living species.

In this context, the paper, “Use of Distribution Pattern of an Oligochaetan Species, Limnodrilus hoffmesteri for Assessment of Pollutional Stress in Hooghly Estuarine Ecosystem”, by Paramita Banerjee and Samir Banerjee, aims to record the incidence of Limnodrilus hoffmesteri in accordance with the physicochemical nature of this species. The work describes the assessment of the role of oligochaetan organisms in water quality regulation. The applicability of these data for the evaluation of the status of ecosystems and their management is important. The response of macrobenthic forms to toxicants is sensitive tool to assess marine pollution.

In the second paper, “Habitat-Based Diversity Assessment of Mangroves of Thane Creek, West Coast, India”, the authors, Mahesh Shindikar, P Tetali and V R Gunale, have attempted to quantify mangrove diversity of Thane creek in relation to natural or man-made habitats with the help of quadrate study. Mangroves are salt-tolerant characteristic complex plant communities occurring in sheltered coastline areas in the tropical and sub-tropical intertidal regions of the world. The species provide important nutrient inputs and act as primary sources of energy for tropical estuaries. Mangroves stabilize the shoreline and act as a bulwark against the devastating impact of hurricanes and cyclones as well as encroachment by the sea, and check soil erosion. Mangrove flora in Mumbai is facing a serious threat of extinction because of increasing urbanization. The paper focuses on the urgent need for giving a serious consideration to conserve and protect this unique ecosystem since the ecological and economic significance of mangroves are vital to environment.

The third paper, “A Simple and Rapid Method for Isolation of High Quality Genomic DNA from the Biofuel Plant – Jatropha curcas L.”, by Rekha R Warrier, R Anandalakshmi, B Devika Nagalakshmi, C Savitha, A Nicodemus and B Gurudev Singh, deals with an improved and rapid method for DNA isolation from a biofuel plant, Jatropha curcas. The plant has been claimed to be an alternative for fossil fuel. The current research on alternative reliable source of renewable energy for fossil fuel has gathered wmuch global attention. In the arid and semi-arid regions, particularly on the degraded lands and lands affected by moving sands, Jatropha curcas L. has proved to be a promising oil-bearing tree. Since high quality DNA isolation from tree species is difficult due to the interference of large amounts of polysaccharides and secondary metabolites,he rapid method described by the authors will be a valuable molecular biology tool for further analysis of the plant.

The fourth paper, “Mass In Vitro Propagation of Rosa hybrida cv. King’s Ransom Through Enhanced Axillary Shoot Formation”, by A Roy, J Dutta, A Bhattacharya and P K Saha, describes the micropropagation of Rosa hybrida cv. King’s Ransom, a commercially demanded variety. Rose plant has horticultural importance and high domestic and overseas demand. New varieties are constantly being developed with better qualities. In vitro micropropagation of rose has played a very important role in rapid multiplication of cultivars with desirable traits and production of healthy and disease-free plants. The paper is of valuable information for horticulturists.

The fifth paper, “Azide Resistance Among Beneficial Rhizobacteria in Relation to Nitrogenase Activity”, by Anuradha Godara, Manjula Vasudeva, Sunita Jain, Rachna Yadav and Neeru Narula, investigates azide resistance among resistant and sensitive mutants of Azotobacter, Gluconacetobacter and Azospirillum. Atmospheric Nitrogen is fixed biologically by widespread soil rhizobacteria like Azotobacter, Gluconacetobacter and Azospirillum, etc. These rhizobacteria proliferate in the host plant’s rhizosphere, fix atmospheric nitrogen and supply it to the plants. Resistance to azide can be used as a potentially useful method to select efficient strains to be used as biofertilizer for various crops. The detailed biochemical aspects provided in the paper highlight the importance of nitrogen fixation for agriculture.

In the sixth paper, “Antimicrobial and Antioxidant Activity of Root Extract of Aristolochia bracteata Retz”, by Angalaparameswari S, Madhu Sudhana Chetty C, Alagusundaram M, Thiruvengada Rajan V S and Sarovar Reddy V, the antimicrobial activity of different extracts from the roots of Aristolochia bracteata retz was tested against Staphylocccus aureus, Escherichia coli, Salmonella typhi and Salmonella typhimurium, which are pathogenic bacteria that cause gastrointestinal disorders. The extracts were subjected to microbiological tests. The use of different parts of several medicinal plants to cure specific ailments has been in vogue since ancient times in every region of India. The medicinal plants constitute a group of industrially important crops which bring appreciable income to the country. The antibacterial and antioxidant properties of these roots are of therapeutic value and offer the benefits of naturopathy.

In the last paper, “The Role of Organics and Probiotics in Shrimp Culture”, by R Saravanan, S Rajagopal and P Vijayanand, the authors have attempted to study the use of organics and probiotics in the culture of black tiger shrimp, Penaeus monodon. The paper highlights the potential sources of probiotics, mechanism of action, diversity of probiotic microbes and challenges of probiotic usage in shrimp aquaculture. Organically farmed seafood is gaining much popularity. The global market for the organic food is booming. Organic fertilizers such as manure, cottonseed meal, soybean meal, rice bran, alfalfa meal and other processed grains or hays are used to improve pond productivity in organic farming. The use of beneficial bacteria (probiotics) to displace pathogens by competitive processes is being used in organic farming as a better remedy than administering antibiotics. Shrimp aquaculture constantly requires new techniques in order to increase production yield. Modern technologies, such as use of probiotics, are important tools that could lead to a higher quality and greater quantity of products. The study is economically viable for shrimp culture.

-- S B Mukherjee Consulting Editor