Effect of stocking density and journey length on the welfare of rohu (<Emphasis Type="Italic">Labeo rohita</Emphasis> Hamilton) fry

The effect of higher packing density and increased duration of transport on the survival and key metabolic enzymes of Labeo rohita fry was investigated. L. rohita fry (length 40 ± 5 mm, weight 0.60 ± 0.13 g) were packed in two different densities 40 and 80 g/l and sampled at 0, 12, 24, and 36 h after packing. Results showed that packing density and length of confinement severely affected the survival of the fry. The whole-body glucose level and the activities of the enzymes, lactate dehydrogenase (LDH), malate dehydrogenase (MDH), glucose-6-phosphatase (G6Pase), fructose-1, 6-bisphosphatase (FBPase), aspartate amino transferase (AST), alanine amino transferase (ALT), and adenosine triphosphatase (ATPase) assayed from the fish whole-body significantly (P < 0.05) increased due to increase in the length of the confinement. However, acetylcholine esterase (AchE) activity decreased significantly (P < 0.05) with increase in the length of confinement. Similarly, higher packing density also significantly (P < 0.05) increased the glucose level and activities of all these enzymes (except AchE). The results revealed that both higher packing density and increased transportation duration mobilize protein resources for glucose production via gluconeogenesis and subsequently activate the glycolysis pathway for energy. The rise in the ATPase activity indicates disruption of the osmoregulatory function and the role of this enzyme in ameliorating it. Overall results suggest that normally practiced packing density of 40 g/l is optimum up to 24-h duration for seed transportation.     

Biochemical and histological changes in the brain tissue of spotted murrel, <Emphasis Type="Italic">Channa punctatus</Emphasis> (Bloch), exposed to endosulfan

The present experiment was conducted to establish the relationship between selected physiological parameters and histological responses of Channa punctatus brain tissue to endosulfan exposure. The fish (35.6 ± 0.7 g) was exposed to sublethal endosulfan concentration (8.1 μg l⁻¹) for a period of 12, 24, 36, 48, 72, and 96 h. Results showed that brain glucose level increased significantly after exposure, indicating a hyperglycemic state of the fish. Brain vitamin C level decreased with an increase in the exposure time. Acetylcholine esterase and adenosine triphosphatase enzyme activities also showed a significant reduction upon endosulfan exposure. Brain histopathology after 96 h endosulfan exposure showed that the apical lobe of the cerebrum (the only portion examined) had mild necrosis. Focal area of gliosis could be seen in the cerebrum, which were absent in the control fish. The results indicate that exposure of sublethal concentration of endosulfan to C. punctatus may have a direct effect on the histology of the fish's brain tissue, thereby affecting its metabolism.     

Identification of informative SSR markers capable of distinguishing hybrid rice parental lines and their utilization in seed purity assessment

With the objective of identifying SSR markers that can distinguish parental lines of rice hybrids, we characterized 10 each of cytoplasmic male sterile (CMS) and restorer (R) lines along with 10 popular Indian rice varieties using a set of 48 hyperpolymorphic SSRs distributed uniformly across the rice genome. All the SSR markers were polymorphic, amplifying a total of 163 alleles, with an average of 3.36 ± 1.3 allelic variants per locus. Twenty-seven SSR markers showed amplification of an allele, which was very specific and unique to a particular parental line and not amplified in any other rice genotype tested. Through multiplex PCR, SSR marker combinations that were unique to a particular parental line or hybrid were also identified. With a set of 10 SSR markers, all the public bred Indian rice hybrids along with their parental lines could be clearly distinguished. To utilize these SSR markers effectively for detection of impurities in parental lines, a two dimensional bulked DNA sampling strategy involving a 20 × 20 grow-out matrix has been designed and used for detection of contaminants in a seed-lot of the popular CMS line IR58025A. We have also designed a multiplex PCR strategy involving single tube analysis using 2–3 markers for hybrid seed purity assessments and demonstrate its superiority over single marker analysis in accurate detection of impurities in hybrids. Implications of parental and hybrid specific SSR markers and strategies to utilize the informative SSR markers for detection of contaminants in a cost effective manner are discussed.     

Surface modifications of natural Kanchipuram silk (pattu) fibers using glow discharge air Plasma

Experimental investigations have been carried out to modify the surface properties of natural Kanchipuram silk (pattu) fibers using a low temperature DC glow discharge air Plasma. Silk is an externally spun fibrous protein secretion formed into fibers. Plasma treatment is an eco-friendly, dry, and clean process over wet chemical method and does not suffer from any environmental and health concerns. Experiments have been performed considering three parameters such as discharge current, treatment time, and working pressure. The structural, thermal, morphological, optical, and mechanical studies of raw and plasma treated silk fibers have been obtained out using attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) spectroscopy, X-ray diffraction (XRD), thermo gravimetric analyzer (TGA), scanning electron microscope (SEM) with energy dispersive spectroscopy (EDS), diffuse absorbance spectroscopy, and tensile test. A comparative study has been done for the untreated and different treated fibers. Various characterization analyses reveal that surface roughness of the plasma treated silk fiber is increased and also crystallite size of treated samples is enhanced, plasma treated silk fibers maintain the whiteness effect and it is observed that UV transmittance region (A & B) is more for the treated fiber which signifies enhanced UV protection.     

Marker assisted introgression of bacterial blight resistance in Samba Mahsuri,an elite indica rice variety

Samba Mahsuri (BPT5204) is a medium slender grain indica rice variety that is very popular with farmers and consumers across India because of its high yield and excellent cooking quality. However, the variety is susceptible to several diseases and pests, including bacterial blight (BB). We have used PCR based molecular markers in a backcross-breeding program to introgress three major BB resistance genes (Xa21, xa13 and xa5) into Samba Mahsuri from a donor line (SS1113) in which all the three genes are present in a homozygous condition. At each backcross generation, markers closely linked to the three genes were used to select plants possessing these resistance genes (foreground selection) and microsatellite markers polymorphic between donor and recurrent parent were used to select plants that have maximum contribution from the recurrent parent genome (background selection). A selected BC₄F₁ plant was selfed to generate homozygous BC₄F₂ plants with different combinations of BB resistance genes. The three-gene pyramid and two-gene pyramid lines exhibited high levels of resistance against the BB pathogen. Under conditions of BB infection, the three-gene pyramid lines exhibited a significant yield advantage over Samba Mahsuri. Most importantly, these lines retain the excellent grain and cooking qualities of Samba Mahsuri without compromising the yield as determined in multi-location trials. This work demonstrates the successful application of marker-assisted selection for targeted introgression of multiple resistance genes into a premium quality rice variety. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. R. M. Sundaram and M. R. Vishnupriya have contributed equally to this work.     

Compositional analysis and rheological properties of gum kondagogu (Cochlospermum gossypium): a tree gum from India

Gum kondagogu ( Cochlospermum gossypium) is a tree exudate gum that belongs to the family Bixaceae. Compositional analysis of the gum by HPLC and LC-MS revealed uronic acids to be the major component of the polymer ( approximately 26 mol %). Furthermore, analysis of the gum by GC-MS indicated the presence of sugars such as arabinose (2.52 mol %), mannose (8.30 mol %), alpha- d-glucose (2.48 mol %), beta- d-glucose (2.52 mol %), rhamnose (12.85 mol %), galactose (18.95 mol %), d-glucuronic acid (19.26 mol %), beta- d-galactouronic acid (13.22 mol %), and alpha- d-galacturonic acid (11.22 mol %). Gum kondagogu, being rich in rhamnose, galactose, and uronic acids, can be categorized on the basis of its sugar composition as a rhamnogalacturonan type of gum. The rheological measurements performed on the gum suggest that above 0.6% (w/v) it shows a Newtonian behavior and shear rate thinning behavior as a function of gum concentration. The viscoelastic behavior of gum kondagogu solutions (1 and 2%) in aqueous as well as in 100 mM NaCl solution exhibits a typical gel-like system. The G' (viscous modulus)/ G' (elastic modulus) ratios of native gum kondagogu (1 and 2%) in aqueous solution were found to be 1.89 and 1.85 and those in 100 mM NaCl to be 1.54 and 2.2, respectively, suggesting a weak gel-like property of the polymer. Crossover values of G' and G' were observed to be at frequencies of 0.432 Hz for 1% and 1.2 Hz for 2% for native gum in aqueous condition, indicating a predominantly liquid- to solid-like behavior, whereas crossover values of 2.1 Hz for 1% and 1.68 Hz for 2% gum in 100 mM NaCl solution suggest a larger elastic contribution.     

印度阿萨姆帮丘陵林地优势种竹子群聚开花情况:物候学、再生、对农村经济的影响以及保护

We recorded gregarious flowering of three bamboo species viz. Bambusa arundinacea, Bambusa tulda and Melocanna baccifera during rainy season from early March to late May, 2008 at lowland forest of Bajali area of Indo-Burma hotspot region. A regular method of field sampling of various forest types was used to map the bamboo species in Assam, India. Moreover, people’s perception on bamboo blooming was investigated at 17 sample plots covering 258 respondents inhabiting at the site at an average of 15 in each plots. A floral clump (inflorescence) emerged and developed into a giant panicle comprising of numerous florets. Two types of seeds viz. bacca and caryopsis were recorded in different species. Viviparous germination was noticed in few bacca seeds produced by M. baccifera and this has unusual occurrence in bamboo. Seed viability test shows that 75% caryopsis seeds were viable; these seeds had the potential of germination and can be used for mass regeneration. Most local respondents believe that bamboo flowering can result in population explosion of rodent, therefore, they think bamboo flowering is positively correlated with famine. This traditional belief results in massive destruction of bamboo clumps, which significantly impacts on rural economy.     

Temporal responses of soil biological characteristics to organic inputs and mineral fertilizers under wheat cultivation in inceptisol

A 2-year field experiment was conducted in wheat ecosystem to assess the key soil biological characteristics in inceptisols of northeastern region of India. Nine treatments using organic inputs (farmyard manure and vermicompost) and mineral fertilizers were applied by modulating the doses of organics and mineral N fertilizer. Soil enzymes (urease, phosphatase, dehydrogenase, fluorescein diacetate (FDA) and arylsulphatase), microbial biomass carbon (MBC), bacteria and fungi populations were measured before seed sowing (GS₁), at flowering stage (GS₂) and after harvest (GS₃) of wheat, whereas total organic carbon (TOC) was studied at GS₃. GS₂ recorded significantly higher soil enzyme activities, except FDA, which increased considerably at GS₃. Enzyme activities, available N and TOC significantly (p ≤ 0.05) enhanced with application of organic inputs even with reduced (50%) mineral N. Except urease and phosphatase, other enzymes did not respond significantly to mineral fertilization. Vermicompost application increased mean enzyme activities, MBC, microbial growth and TOC fractions (particulate organic carbon, humic acid and fulvic acid carbon) than farmyard manure. Significant (p ≤ 0.05) positive correlations (r = 0.61–0.87) were obtained between TOC and its fractions with studied soil enzymes. Thus, in conclusion, 5 t ha^–1 organics incorporation (especially vermicompost) in wheat fertility programme can uphold soil biological health, reduce (50%) N application and would be a sustainable option for wheat grown in inceptisols of northeastern region of India.     

Medetomidine a novel immobilizing agent for the elephant (Elephas maximus)

Medetomidine was injected by the intramuscular route at the rates of 3 and 5 microg/kg body weight into two groups of Indian elephants (Elephas maximus). Sedation was induced at 6.20 (0.81) and 5.90 (0.60) min respectively after injection. The duration of anaesthesia was 66.20 (10.4) and 134.20 (24.12) min, respectively and recovery occurred at 125.80 (25.23) and 205.89 (29.3) min. The notable signs of sedation exhibited by the elephants were protrusion of penis, complete relaxation of trunk, flaccidity of tail and drooping of the ears with a head down position. During sedation, physiological parameters recorded were bradycardia, decreased respiration and hypothermia.