Mortality of the tobacco caterpillar,Spodoptera litura (F.), when treated withBacillus Thuringiensis combinations with boric acid and insecticides

Bacillus thuringiensis Berliner in combination with 0.1, 0.5, 1.0, 1.5 and 2% boric acid caused 100% mortality of the tobacco caterpillar,Spodoptera litura (F.), irrespective of instar, in a much shorter period (1.77 to 3.61 days) than with boric acid or the pathogen alone. The toxicity ofB. thuringiensis in combination with dicrotophos at 0.02 and 0.04%, with fenitrothion at 0.025 and 0.05%, or with dichlorvos at 0.01 and 0.05%, was enhanced.     

In situ determination of the nanoscale chemistry and behavior of solid-liquid systems

Many fundamental questions in crystal-growth behavior remain unanswered because of the difficulties encountered in simultaneously observing phases and determining elemental concentrations and redistributions while crystals nucleate and grow at the nanoscale. We show that these obstacles can be overcome by performing energy-dispersive x-ray spectroscopy on partially molten Al-Si-Cu-Mg alloy particles during in situ heating in a transmission electron microscope. Using this technique, we were able to (i) determine that the aluminum and silicon concentrations change in a complementary and symmetric manner about the solid-liquid interface as a function of temperature; (ii) directly measure the solid- and liquid-phase compositions at equilibrium and in highly undercooled conditions for quantitative comparison with thermodynamic calculations of the liquidus and solidus phase boundaries; and (iii) provide direct evidence for homogeneous nucleation of the aluminum-rich solid.     

Fecal and urinary lignans, intrafollicular estradiol, and endometrial receptors in lactating dairy cows fed diets supplemented with hydrogenated animal fat, flaxseed or sunflower seed

We hypothesized that the inclusion of flaxseed in the diets of lactating dairy cows will increase urinary and fecal concentrations of the lignans, secoisolariciresinol diglycoside (SDG), enterolactone and enterodiol, reduce intrafollicular concentrations of IGF-I and estradiol, and subsequently reduce estradiol and oxytocin receptor expression in the endometrium. To test this hypothesis, 27 cycling, lactating Holstein cows were assigned to 1 of 3 diets supplemented with saturated fatty acids (SAT), flax (FLX), or sunflower (SUN) seed. Rations were formulated to provide 750 g supplemental fat/cow/d in all dietary groups. Ovulation (Day 0) was synchronized, and 5 d later, follicles>8 mm were ablated by an ultrasound-guided procedure in all cows. Samples of blood (Days 0 to 14), follicular fluid (Day 5 and 15), endometrium (Day 15), as well as urine and feces were collected in a subset of the animals. The fecal concentrations of SDG and enterodiol were higher (P<0.05) in cows fed FLX than in those fed SAT or SUN. Enterodiol increased (P<0.05) in urine samples of cows fed FLX, compared to those of cows fed SUN. However, follicular estradiol concentrations on Day 5 and 15 and endometrial concentrations of estradiol and oxytocin receptors on Day 15 did not differ among the dietary groups. Mean plasma progesterone concentrations were higher (P<0.05) in cows fed FLX and SUN than in those fed SAT. In summary, a diet supplemented with flaxseed increased the concentrations of SDG and enterodiol in feces, as hypothesized, but did not alter intrafollicular concentrations of IGF-I or estradiol, or endometrial populations of oxytocin or estrogen receptors in lactating dairy cows.     

Antifeedant activity of vicolides from Pentanema indicum

Vicolides A–D (0.2–2000 ppm) from Pentanema indicum showed antifeedant activity against Euproctes fraterna and Pericallia ricini V stage larvae.     

Resistance of pearlspot larvae,Etroplus suratensis,to redspotted grouper nervous necrosis virus by immersion challenge

Viral nervous necrosis (VNN) affects more than 120 species mostly belonging to the order Perciformes. However, none of the brackishwater species belonging to the family Cichlidae under the order Perciformes are reported to be susceptible. Hence, the present experiment was undertaken to study the susceptibility of the brackishwater cichlid, pearlspot, Etroplus suratensis to NNV. Thirty‐day‐old pearlspot larvae were infected with NNV by immersion. Mortality was recorded till 14 days post‐infection, and the infected larvae were subjected to nested RT‐PCR and histology. The virus was isolated from infected larvae using SSN‐1 cells. To study the replication of the virus in vitro, primary cultured brain cells of E. suratensis and IEK cells were infected with NNV. No mortality was observed in any of the control or experimentally infected larvae. However, the experimentally infected larvae were positive for NNV by nested RT‐PCR and the virus was isolated using SSN‐1 cells. Further, the infected pearlspot brain cells and IEK cells showed cytopathic effect at second and third passage of the virus and they were positive for NNV by nested RT‐PCR. Pearlspot is relatively resistant to VNN although the virus could replicate in the larvae and in cell culture.     

Estimation of paddy water productivity (WP) using hydrological model: an experimental study

Water productivity (WP) expresses the value or benefit derived from the use of water. A profound water productivity analysis was carried out at experimental field at Field laboratory, Centre for Water Resources, Anna University, India, for rice crop under different water regimes such as flooded (FL), alternative wet and dry (AWD) and saturated soil culture (SSC). The hydrological model soil-water-atmospheric-plant (SWAP), including detailed crop growth, i.e, WOFOST (World Food Studies) model was used to determine the required hydrological variables such as transpiration, evapotranspiration and percolation, and bio-physical variables such as dry matter and grain yield. The observed values of crop growth from the experiment were used for the calibration of crop growth model WOFOST. The water productivity values are determined using SWAP and SWAP–WOFOST. The four water productivity indicators using grain yield were determined, such as water productivity of transpiration (WP_T), evapotranspiration (WP_ET), percolation plus evapotranspiration (WP_ET+Q) and irrigation plus effective rainfall (WP_I+ER). The highest value of water productivity was observed from the flooded treatment and lowest value from the saturated soil culture in WP_T and WP_ET. This study, reveals that deep groundwater level and high temperature reduces the crop yield and water productivity significantly in the AWD and SSC treatment. This study reveals that in paddy fields 66% inflow water is recharging the groundwater. There is good agreement between SWAP and SWAP–WOFOST water productivity indicators.     

Inland saline aquaculture increased carbon accumulation rate and stability in pond sediments under semi-arid climate

Purpose

Similar to fresh- and brackish water aquaculture ponds, commercial shrimp farming in degraded saline areas holds the potential to bury carbon (C) in the sediments. However, studies on the mechanisms of sediment C dynamics and C-flux in response to inland saline aquaculture management practices are still scarce. Therefore, the objectives of the present study are to quantify the C burial rate in inland saline aquaculture ponds and assess the impact of inland saline aquaculture on sensitive C fractions in the bottom sediment of the ponds.

Materials and methods

The sediment samples (n?=?12 from each pond) were collected from six shrimp farming ponds (1000 m² area of each pond) of different ages. The sediment depth, sediment accumulation rate and the levels of total carbon (TC), total organic carbon (TOC) and sediment oxidizable organic carbon (SOC) and its different fractions were determined using standard procedures. The data were analysed by one-way analysis of variance (ANOVA), followed by the Duncan's multiple range test for comparing the means, and the Pearson correlation test was used to assess the relationship between the different pond sediment parameters and SOC content.

Results and discussion

The results revealed that the annual C accumulation rates varied from 902 to 1346 kg C ha^?1 year^?1 in 7-year-old earthen ponds (EPs) and bottom cemented ponds (BCPs), respectively. The sediment C fractions, including TC, TOC, SOC and its fractions (very labile, VLc; labile, Lc; less labile, LLc), and non-labile carbon (NLc)) were progressively increased over the pond age. The inland saline aquaculture practices over the years increased both active (AC) and passive carbon (PC) pools in the pond sediments, helped in the restoration and improvement of sediment quality and enhanced C sequestration potential of the sediments. Furthermore, a significant increase in the level of particulate organic carbon (POC) in BCPs justified that the non-ploughing practices at BCPs facilitated the formation of macro- and micro-aggregates, thereby increasing the C retention and stability of the pond sediments.

Conclusion

This study suggested that the shrimp farming ponds in semi-arid saline soils represented considerable C burial hotspots, enhanced the stable passive C pools and improved the sediment quality.

     

Novel mechanism of modulating natural antioxidants in functional foods: involvement of plant growth promoting Rhizobacteria NRRL B-30488

The significance of plant growth-promoting rhizobacteria (PGPR) mediated increase in antioxidant potential in vegetables is yet unknown. The plant growth-promoting bacterium Bacillus lentimorbus NRRL B-30488 (B-30488) mediated induction of dietary antioxidant in vegetables ( Trigonella foenum-graecum, Lactuca sativa, Spinacia oleracea, and Daucus carota) and fruit ( Citrus sinensis) after minimal processing (fresh, boiled, and frozen) was tested by estimating the total phenol content, level of antioxidant enzymes, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide scavenging activities along with integral radical scavenging capacity by photochemiluminescence assay and inhibition of lipid peroxidation. Minimal processing of vegetables showed that T. foenum-graecum had the highest phenol content in B-30488-treated plants followed by L. sativa, D. carota, and S. oleracea. Thermally treated vegetables T. foenum-graecum (26-114.5 GAE microg mg (-1)) had an exceptionally high total phenolic content, followed by D. carota (25.27-101.32 GAE microg mg (-1)), L. sativa (23.22-101.10 GAE microg mg (-1)), and S. oleracea (21.87-87.57 GAE microg mg (-1)). Among the vegetables and fruit used in this study for enzymatic estimation, induction of antioxidant enzymes, namely, polyphenol oxidase (PPO), ascorbate peroxidase (APX), catalase (CAT), and superoxidase dismutase (SOD), was observed in edible parts of T. foenum-graecum, L. sativa, S. oleracea, and D. carota, after inoculation with B-30488. The scavenging capacity of the vegetables treated with B-30488 against DPPH and superoxide anion radical activity was found to be significantly high as compared to nontreated control. Mild food processing had no adverse effect on radical scavenging capacity. Photochemiluminescence also ascertains the above findings. The ability of the plant extracts to protect against lipid peroxidation and its ability to prevent oxidation of reduced glutathione (GSH) was measured in rat liver homogenate, and the results suggested that the inoculated plant exhibited better activity in all of the screened plants. Significant increases in shoot length, root length, and dry weight, averaging 164, 132, and 135% in T. foenum-graecum, 174, 141, and 156% in L. sativa, 129, 141, and 59%, in S. oleracea, and 125, 146, and 42% in D. carota, respectively, over untreated controls, were attained in greenhouse trials. To the best of the authors' knowledge, this is the first report of PGPR-mediated induction of antioxidant enzyme activity (PPO, APX, CAT, and SOD) along with the antioxidant activity of the extracts in both in vitro (DPPH radical scavenging and superoxide scavenging) and ex vivo conditions using the rat liver tissue (percent inhibition of lipid peroxidation and prevention of oxidation of GSH) and phenolic content. The results demonstrate the PGPR-mediated induction of antioxidant level in vegetables and fruit controls oxidative damage even after minimal processing and thus is indicative of its potential as a viable substitute of synthetic antioxidants.