Science Vision

160-165

Authors: M. H. Lalramdinfeli, H.T. Lalremsanga

The breeding behaviour and the advertisement calls of the giant tree frog, Rhacophorus maximus was studied during the breeding season in Mizoram University Campus, Aizawl, Mizoram. At the first shower of the onset of monsoon, advertisement calls of male attract females to breeding areas and announce other males that a given territory is occupied. The aim of this study was to provide the detailed information on the breeding behaviour and analysis of advertisement calls of Rhacophorus maximus. Advertisement calls were emitted in series with variable call intervals. The morphometric measurement of the amplecting pairs were recorded and females are found to be larger than males.

171-176

Authors: R. Lalfakzuala, H. Lalrinfeli, H. Lalruatsanga

Living organism requires certain metals for their growth and metabolism and evolved an appropriate uptake mechanism for metals. However, it is particularly difficult to establish mutual relationship when soil is continuously contaminated with various heavy metals. Phosphatase enzyme significantly accelerates the release of inorganic P from organic compounds and returns it to the soil. Therefore, the study of Phosphatase enzyme that releases P from organic compounds by dephosphorylation of phosphor-ester or phosphoanhydride bond in an organic matter is an important tool in initiating biofertilizer for specific crops. The present study indicated that the availability of metal such as Zinc in its inorganic form can act as an inhibitory factor for the growth and activity of bacteria such as Pseudomonas flourescens and the biomass of P. flourescens decrease with increase ZnCl2 concentration. It can be concluded that ZnCl2 acts as an inhibitor to the growth of P. flourescens and also the presence of ZnCl2 in the growth medium decreases the phosphatase enzyme activity of the bacteria, which reveal that metals can also affect the activity of the microbes.

106-113

Authors: C. B. Lalramliani, C. Lalnunzira, S. K. Tripathi

We studied litter decomposition and nutrient release patterns in different components of two nitrogen (N) fixing shrub species, (Flemingia macrophylla and Tephrosia candida) planted on sloping agriculture land technology (SALT) farm in 2002 and 2010. The two sites were 10 yrs old and 2 yrs old farms at the beginning of this study, i.e. July 2012. Sites were within the same permanent agriculture farm having similar climatic conditions. We collected different litter components (leaves green and senesced, wood and roots fine and coarse) of two species having different ages. Known amount (7 g) of all litter components were enclosed in nylon net mesh bags and placed in their respective habitats for decomposition and these samples were retrieved periodically to assess the rate of change of mass and nutrient. Our results suggest that the mean relative decomposition rates of different litter were maximum in the rainy season and minimum in the summer season for both sites and species. Among the litter components, fine roots (<2 mm) of both species showed higher rates of organic matter decomposition and rates of nutrient release to the soil. The rate of release of organic matter and nutrient was slightly greater in F. macrophylla than the T. candida. Annually, these species added significant amount of organic matter and nutrients to the soil that supported considerably higher production compared to shifting cultivation sites on sustained basis.

123-134

Authors: K. Vanlaldinpuia, P.B. Lalthanpuii

In recent years, asymmetric organocatalysis has emerged as powerful tools for the synthesis of a variety of chiral molecules. Ready availability of the catalysts, low toxicity, simple operational procedures and mild reaction conditions associated with organocatalysis makes it an attractive method to synthesise diverse complex structures. Here, a short review on the development and applications of chiral organocatalysts for asymmetric Michael addition reactions has been described.

144-150

Authors: C. Malsawmtluangi, Lalramliana

The study deals with the prevalence of helminth parasites in Mastacembelus armatus, a spiny eel, collected from the rivers of Mizoram. The study gives the first overview on the helminth community infecting M. armatus in the rivers of Mizoram and reveals the presence of nematode, cestode and trematode. The cestodes recovered belongs to the genus Senga sp. and Bothriocephalus sp. whereas the nematode belong to the genus Spinitectus sp., Neocamallanus sp., Capillaria sp. and Eustrongylides sp. and the trematode Clinostomum sp. Nematode was found to be the most predominant parasitic group followed by cestode and the trematode respectively. The Tuikum and Tuirial rivers flowing near the garbage dumping ground show the maximum diversity with all the three group of parasites present. Among the helminth parasite recovered the nematode Capillaria sp. and the trematode Clinostomum sp. are both considered potential zoonoses.

59-67

Authors: L. Hnamte, C. Lalrammawia, B. Gopichand

Intensive jhum cultivation is the biggest ecological threat due to its associated problems such as biodiversity loss, deforestation, soil erosion and the gradual reduction of land productivity in Mizoram. The intrinsic practice of jhum cultivation still dominated the farming system in Mizoram to a large margin. Four levels of nitrogen, phosphorus and potassium soil fertilizer application in local maize variety was conducted in 2 years, 3 years and 5 years jhum cycles. Strong significant (P<0.05) response to fertilizer application occurred in the growth and yield performance of maize. Different period of jhum cycles also had significant (P<0.05) effect in growth and yield with highest productivity in longest jhum cycle. Taking account of the poor soil nutrient content and the acidic soil in Mizoram, application of urea at lower rate under longer jhum cycle may be adopted.

74-81

Authors: J. Blick, S. Kumar, V. K. Bharati, S. Kumar

Arsenic is a naturally occurring element found primarily in rocks, soil, water, and plants in the Indian sub-continent. Natural events, such as infiltration to water, dissolution of minerals from clay, and erosion of rocks, can release arsenic into water. Arsenic is usually found in inorganic forms in water, the most predominant form being arsenate [As (V)], with arsenite [As (III)] under some conditions. In organism, it bonds with carbon and hydrogen, forming organic arsenic. The contamination of groundwater by arsenic in Chawngte, Mizoram, India is likely to happen due to its sharing of a common land border with Bangladesh. Groundwater and rainwater are the most important supplementary sources of drinking water in region. Hence, residents of Chawngte are relying on tuikhurs (spring) and other natural sources. It has been observed that several number of tube wells, tuikhurs and hand pumps, exist in any cluster or community. Generally, not all tube wells and hand pumps in an area are affected by arsenic. Therefore, the immediate challenge is to find out the unaffected ones in the affected areas and commence routine monitoring in order to stop using the currently affected tube wells as soon as arsenic is detected. The physico-chemical parameters like pH, EC, TDS, total hardness, total chlorides, iron and free chlorine are well within the acceptable limits for drinking water. Arsenic and turbidity are slightly higher than the acceptable limits but still within the permissible limit of 0.05 mg/l and 5 NTU respectively.

10-15

Authors: R. Pathak

Thermochemical studies of metal compounds of ‘s’ and ‘f’ block elements and those of organometallic compounds are of immense importance because not only they furnish invaluable information regarding analysis and characterization of the compound thermodynamically but also give vital information regarding ‘specific enthalpy’ and ‘enthalpy density’. Thus viability and analysis of input and output of energy is of prime concern before any process or reaction or for that matter if any engine or industry is being set up because after all it is the process or reaction which takes place inside the engine. As the globe is gradually but certainly moving away from fossil fuel or carbon-based energy production as it immensely pollutes the environment due to evolution of greenhouse gases into the environment and contribute towards global warming, it is but necessary to evaluate the impact assessment of the pollutants on the environment before any engine or industry is being developed or installed. It is in this perspective that the thermochemical studies of metal compounds of ‘s’ ‘p’ ‘d’ and ‘f’ block elements and those of organometallic compounds become extremely important as it clearly identifies and defines the products as well as absorption and evolution of energy involved therein.

21-26

Authors: H.C. Lalramnghaki, Vanlalhlimpuia, Vanramliana, Lalramliana

The study investigates the effect of temperature on the infectivity of two entomopathogenic nematodes, viz. Steinernema sp. and Heterorhabditis indica, locally isolated from Mizoram, northeastern India, using last instar larvae of greater wax moth, Galleria mellonella, as an insect host. Two hundred infective juveniles/larva of wax moth were exposed to different temperatures, viz. 10, 15, 20, 25, 30 and 35°C. It is observed that temperature play a significant role in infectivity of the two nematodes. No establishment of IJs were observed at 10°C, in addition 15°C in H. indica, and 35°C. Steinernema sp. appeared to be best adapted to temperatures between 15 and 30°C with an optimum temperature range of 25-30°C, whereas H. indica appeared to be adapted to temperatures between 20 and 30°C with an optimum temperature of 30°C.

37-45

Authors: K. Lalchhandama

Ethidium bromide is a celebrity stain, and a very tainted one, in molecular biology. Its stigmatisation as a toxic, carcinogenic and mutagenic chemical has stirred an uncalled-for but what seems like a calculated hysteria among researchers. This has merely actuated what can be described as a necessary advertising war. The so-called safer alternatives are not overwhelmingly superior or entirely safe. For example, SYBR Green is, by evidence, more mutagenic. They may be regarded as optional, but at a higher financial cost. If anyone feels safer with extravagance, then the optional stains are an obvious choice. EtBr had been the principal drug for the mass treatment of cattle trypanosomiasis since the early 1950s, and no cancer has been reported among cattle. There are researchers who has handled the chemical throughout their career for decades, and none had made any complaint whatsoever. There is no medical record of molecular biologists taking cancer therapy because of EtBr. Milk producers are using it in large quantities. To the further extreme, people have actually drunk it without any apparent adverse effect. This is a lesson to learn that this is a case of bad meme and people have put an undue stain to this useful stain.