a b s t r a c tTwo independent experiments were performed to determine the effects of salinity on survival and growth of juvenile Macrobrachium rosenbergii, first one was to determine the median lethal salinity (MLS-50 96 h ) and second one was to assess the survival and growth at different sub-lethal salinities under field condition. In MLS-50 96 h study 0, 5, 10, 15, 20, 25 and 30 ppt salinities were used to initially find out the salinity tolerance range. Accordingly, a definitive salinity tolerance test was done in next phase to find out exact median lethal salinity by directly transferring the test species to 21, 22, 23, 24, 25, 26 and 27 ppt salinity for 96 h. The median lethal salinity of M. rosenbergii was estimated at 24.6 ppt. In the second experiment, survival and growth performances of the prawn were recorded at different sub-lethal salinities viz., 5, 10, 15 and 20 ppt along with 0 ppt as control during 60 days culture period. The prawn exhibited lowest final average weight at 20 ppt salinity and significantly highest at 10 ppt salinity. Highest SGR and weight gain were obtained at 10 ppt followed by 5 ppt, 15 ppt and 0 ppt salinity but differences among treatment were not significant (P > 0.05). Survival rate of prawn varied between 91% (at 0 ppt) and 78% (at 20 ppt). The prawn grew and survived satisfactorily at 0-15 ppt salinities, implying that the species can be cultured commercially at wide salinity range. M. rosenbergii can be considered as an ideal species to promote, in view of current and future climate variables as more and more coastal areas of India are going to be vulnerable to saline water inundation.

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Brassinosteroids (BRs) play crucial roles in various biological processes, including plant developmental processes and response to diverse biotic and abiotic stresses. However, no information is currently available about this gene family in wheat (Triticum aestivum L.). In the present investigation, we identified the BZR gene family in wheat to understand the evolution and their role in diverse developmental processes and under different stress conditions. In this study, we performed the genome-wide analysis of the BZR gene family in the bread wheat and identified 20 TaBZR genes through a homology search and further characterized them to understand their structure, function, and distribution across various tissues. Phylogenetic analyses lead to the classification of TaBZR genes into five different groups or subfamilies, providing evidence of evolutionary relationship with Arabidopsis thaliana, Zea mays, Glycine max, and Oryza sativa. A gene exon/intron structure analysis showed a distinct evolutionary path and predicted the possible gene duplication events. Further, the physical and biochemical properties, conserved motifs, chromosomal, subcellular localization, and cis-acting regulatory elements were also examined using various computational approaches. In addition, an analysis of public RNA-seq data also shows that TaBZR genes may be involved in diverse developmental processes and stress tolerance mechanisms. Moreover, qRT-PCR results also showed similar expression with slight variation. Collectively, these results suggest that TaBZR genes might play an important role in plant developmental processes and various stress conditions. Therefore, this work provides valuable information for further elucidate the precise role of BZR family members in wheat.

A study was conducted with fry of Catia catia (Hamilton) to investigate the effects of dietary lipid supplements on growth, feed conversion, tissue fatty acid composition and the intestinal lipase activity. Four treatment diets were prepared using purified ingredients incorporating sunflower oil (n-6 fatty acids), cod liver oil (n-3 fatty acid source) and a mixture (1:1) of sunflower and cod liver oil in three diets. The fourth diet was lipid-free and served as the control. The best growth and survival was recorded for fish given the diet having a mixture of n-3 and n-6 fatty acids (weight gain was 380% and survival was 93%), followed by the n-6 diet (320% and 88%), the n-3 diet (290% and 84%) and the lipid-free diet (239.9% and 82%). Feed conversion ratio (FCR) and per cent protein deposited (PPD) followed a similar trend. The intestinal lipase activity (expressed as Jig a-naphthol liberated mg-' protein h"') was 83.3, 74,2, 80.1 and 53.7 for n-3 and n-6, n-6, n-3 and lipid-free diet treatments respectively. The fatty acid profile of the whole body was shown to be influenced by dietary fatty acid composition. The results of this laboratory study indicated that a combination of n-3 and n-6 fatty acids is important for growth and survival of this species. The extent to which such observations will be relevant in field conditions can be stated only after results of feeding trials in ponds are available.

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