The major hindrance in the development and sustainability of aquaculture industry is the occurrence of various diseases in the farming systems. Today, preventive and management measures are central concern to overcome such outbreak of diseases. Immunostimulants are considered as an effective tool for enhancing immune status of cultured organisms. Among different immunostimulants used in aquaculture practices, β-glucan is one of the promising immunostimulant, which is a homopolysaccharide of glucose molecule linked by the glycoside bond. It forms the major constituents of cell wall of some plants, fungi, bacteria, mushroom, yeast, and seaweeds. Major attention on β-glucan was captivated with the gain in knowledge on its receptors and the mechanism of action. The receptor present inside the animal body recognizes and binds to β-glucan, which in turn renders the animal with high resistance and enhanced immune response. This review highlights β-glucan as an immunostimulant, its effective dosages, and route of administration and furthermore provides an outline on role of β-glucan in enhancing growth, survival, and protection against infectious pathogens pertaining to fishes and shellfishes. Study also summarizes the effect of β-glucan on its receptors, recognition of proteins, immune-related enzymes, immune-related gene expression and their mechanisms of action.

A three year experiment was conducted during 2007-2009 to study the effect of sulphur and boron fertilization on yield, quality and nutrient uptake by soybean under upland condition. The experiment comprises five levels of sulphur (0, 10, 20, 30 and 40 kg sulphur per hectare) and five levels of boron (0, 0.5, 1.0, 1.5 and 2.0 kg boron per hectare). The study revealed that yield attributing characters like number of branches per plant, pods per plant and 100 seed weight and yield were increased with the application of sulphur and boron as compare to control. The overall result revealed that application of 30kg sulphur per hectare and 1.5 kg boron per hectare were found to be the optimum levels of sulphur and boron for obtaining maximum yield attributes, yield, oil and protein content, total uptake of sulphur and boron, net return, cost and benefit ratio of soybean under upland condition as compare to other levels of sulphur and boron respectively.

To develop an effective conservation and management strategy, it is required to assess the biodiversity status of an ecosystem, especially when we deal with Indo-Myanmar biodiversity hotspot. Importance of this reaches to an entirely different level as the hotspot represents the area of high endemism which is under continuous threat. Therefore, the need of the present study was conceptualized, dealing with molecular assessment of the fish fauna of Indo-Myanmar region, which covers the Indian states namely, Manipur, Meghalaya, Mizoram, and Nagaland. A total of 363 specimens, representing 109 species were collected and barcoded from the different rivers and their tributaries of the region. The analyses performed in the present study, i.e. Kimura 2-Parameter genetic divergence, Neighbor-Joining, Automated Barcode Gap Discovery and Bayesian Poisson Tree Processes suggest that DNA barcoding is an efficient and reliable tool for species identification. Most of the species were clearly delineated. However, presence of intra-specific and inter-specific genetic distance overlap in few species, revealed the existence of putative cryptic species. A reliable DNA barcode reference library, established in our study provides an adequate knowledge base to the groups of non-taxonomists, researchers, biodiversity managers and policy makers in sketching effective conservation measures for this ecosystem.

Induced breeding of climbing perch, Anabas testudineus was conducted by synthetic hormone Wova-FH in the intensity level of 0.1, 0.2 and 0.3 mL kg À1 of body weight respectively. The brooders were injected one time and left to spawn in the spawning hapa in the sex ratio between male and female as 2:1. It was found that at all the intensity level hormoneWova-FH could enhance the ¢shes to breed and lay eggs whereas no breeding was observed in control set. The spawning time, quantity of the brooder spawn, fertilization rate, hatching rate and survival rate were quanti¢ed in each set of experiment. The egg output/female was signi¢cantly higher in 0.3 mL in comparison with 0.1and 0.2 mL kg À1 of body weight. The statistical analysis showed signi¢cant (P 0.05) e¡ect between hormone dose on fertilization rate, egg output and hatching rate. The present experiment suggests that Wova-FH at the dose of 0.3 mL kg À1 body weight of ¢sh is more e¡ective which might be considered for raising captive population.

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