Changes in growth and pigment content in Sweet potato by triadimefon and hexaconazole

            Triadimefon and hexaconazole are triazole group of fungicides have plant growth regulating properties. The present investigation aimed to study the growth regulating effect of these compounds on sweet potato (Ipomoea batatas L.). Each plant was treated with one litre of aqueous solutions containing 15mg L-1 triadimefon and 10mg L-1 hexaconazole on 40 and 70 days after planting (DAP) by soil drenching. The growth parameters of the plants were estimated on 45, 60, 75, 90 and 105 DAP.  Among the triazole, hexaconazole inhibited the number of leaves, total leaf area, stem length, internodal length, leaf and stem dry weight, relative shoot growth rate significantly when compared to triadimefon.  Triazole (chiefly available and plant control and yield production) treatments increase the root length, root and tuber dry weight, relative tuber growth rate, net assimilation rate root/shoot ratio, leaf dry weight per unit area, chlorophyll and carotenoid content

Screening and fractional purification of antimicrobial compound of Streptomyces sp. MAB 18 isolated from coastal sediment of Nagapattinam, south-east coast of India

662-669A total of 42 strains of actinobacteria were isolated from five different stations. Out of these 42 isolates, the suspected 10 actinobacterial strains were screened and inoculated for purification, and based on the preliminary screening results, MAB18 was taken to investigate the extraction evaluation of its antimicrobial property. Then it was tested against bacterial and fungal pathogens. The highest zone of inhibition was observed against E. coli (8.2±0.8mm), P. aeroginosa (10.4±0.6 mm), Vibrio harveyi (7.2±0.8mm), S. typhi (10.6±-0.4 mm) for bacteria and A. niger (11.2±0.8 mm), and A. flavus (9.8±0.2 mm) C. albicans (10.4±0.6mm), and Penicillium sp. (7.2±0.8mm), for fungi, whereas it was 21.4±0.6 and 20.4±0.6 mm for the standard ampicillin and nystatin. The antibiotic producing actinomycetes may be tapped as one of the India’s potential source of novel antibiotics to be used against both bacterial and fungal pathogenic organisms

Total organic carbon profile in water and sediment in coral reef ecosystem of Agatti Island, Lakshadweep Sea

936-942Total organic carbon profile in sea water (depth-wise) and sediment has been investigated on seasonal basis in the coral reef ecosystem of Agatti island, Lakshadweep sea. The TOC values of sea water and sediment were converted into percentage to understand its level of distribution. The level of TOC in the surface sea water ranged from 0.40 to 1.02 ppm and the level of TOC at the ~5 m depth ranged from 0.18 to 1.86 ppm. The pH did not show any variation depth-wise (7.65 to 8.49). Sedimentary organic carbon (SOC) was found in the range of 0.21 to 2.35 mg C/g. Significant seasonal variation was not found for water TOC and SOC levels. The pH for sediment was recorded from 7.79 to 8.62. Water pH showed significant positive correlation with sediment pH (R2=0.959). The sand fraction was found more in the texture followed by silt and clay. Clay was found to have positive correlation with SOC (P >0.01). The TOC profile in the Lakshadweep sea was found in the order: Surface water TOC < water TOC at ~5 m depth < SOC. The percentage composition of SOC showed more than 1000 times as compared to water TOC. However, the levels recorded in this study are found within the limit prescribed by EPA and its influence on coral reef ecosystem is discussed

Further records of rare brachyuran crab Eucrate indica (Crustacea: Decapoda: Brachyura Euryplacidae) along the Chennai coast, Tamil Nadu, India

This study reports further occurrence of the crab Eucrate indica (Crustacea: Decapoda: Brachyura: Euryplacidae) along the Chennai coast, Tamil Nadu, India. The crabs were obtained from a depth of 40-60 m in the trawl by-catch. The morphological features, color and distribution of these crabs are given

Assessment of Tsunami Impact on fish eggs and larvae along Parangipettai coast (Southeast coast of India)

The tsunami on 26th December, 2004 caused extensive damage to coastal communities and affected many marine ecosystem in southern regions of India and Andaman and Nicobar islands affecting 2,260 km of coastline. The most affected regions were the state of Tamil nadu and the Andaman and Nicobar archipelago. The present research analysis the impact of tsunami on finfish eggs and larvae and its distribution patterns. It deals how the tsunami impinges directly on ichthyoplankton ecology. After the tsunami effect, the eggs and larvae samples were collected and compared with previous year data of the same month (January 2004 and January 2005). We selected five stations, 0.5 1,3,5 and 10 km distance from the shoreline. During the present study a total of 1067 eggs and 285 larvae belonging to 29 families and 57 species were sorted and identified. The pre and post tsunami collection shows the significant variation on eggs and larvae distribution. During pre tsunami and zooplankton biomass was highly correlated with ichtyoplankton density with all the five station significant at 1 % level (p-value <0.01) but there is no correlation observed in the post tsunami samples

Report on the occurrence of the xanthid crab, <em>Demania armadillus</em> (Herbst, 1790) in Kalpakkam coastal waters, southeast India

1699-1701This report is a record of the occurrence of the xanthid crab Demania armadillus (Herbst, 1790) in Kalpakkam coastal waters, southeast India and the morphological features of two female specimens

Further records of rare brachyuran crab Eucrate indica (Crustacea: Decapoda: Brachyura Euryplacidae) along the Chennai coast, Tamil Nadu, India

Este estudo relata uma nova ocorrência do caranguejo Eucrate indica (Crustacea: Decapoda: Brachyura: Euryplacidae) ao longo da costa de Chennai, Tamil Nadu, Índia. Os caranguejos foram obtidos a uma profundidade de 40-60 m, através de captura acidental de arrasto. As características morfológicas, cor e distribuição destes caranguejos são dadas. This study reports further occurrence of the crab Eucrate indica (Crustacea: Decapoda: Brachyura: Euryplacidae) along the Chennai coast, Tamil Nadu, India. The crabs were obtained from a depth of 40-60 m in the trawl by-catch. The morphological features, color and distribution of these crabs are given.

First Record of Indian Hand Fish Halieutaea indica Annandale & Jenkins, 1910 From Chennai Coast, Tamil Nadu, India

882-884The present paper reports the first record of Indian hand fish Halieutaea indica from Kasimedu fishing harbour, Chennai coast. A systematic account of this species, description and distribution are provided. Its similarity with the species of Halieutaea stellata is also reported

Seasonal and spatial distribution of heterotrophic bacteria in relation to physico-chemical properties along Ennore coastal waters

587-597Water samples were examined for total viable count and pollution indicator bacteria (total coliform, fecal coliform, Escherichia coli and Streptococcus faecalis). Salinity, pH, dissolved oxygen, biological oxygen demand, nutrients and Chlorophyll-a were examined to assess the physico-chemical condition of water. Statistically, insignificant seasonal variation was found in bacterial populations. Average abundances (CFU/ml) of the different heterotrophic bacteria of surface waters were: total viable count (2.1×106), total coliforms (1.3×105), fecal coliforms (1.5×104), Escherichia coli (1.1×104) and Streptococcus faecalis (0.4×104).  Spatially, the higher bacterial population was recorded in creek and shore regions with high concentration of nutrients. Significant positive correlation (p 0.05) was observed between bacterial population and the nutrient concentration which suggest that elevated nutrient load favors the bacterial growth. However, bacterial populations showed positive correlations with biological oxygen demand, and negative relationship (p 0.05) with salinity, indicating the dominating influence of anthropogenic activities in the coastal area