Quantification of stress sensitive markers in single fecal samples do not accurately predict excretion of these in the pig

All feces produced during 24 h were collected from five pigs and cortisol and immunoreactive cortisol metabolites (CICM), and IgA were quantified. Within pigs, the concentrations of CICM and IgA varied extensively between random samples obtained from a single fecal dropping, and deviated in most cases significantly from the true concentration measured in total fecal output (CV 6.7-130%). The CICM and IgA contents varied considerably (CV 8.1-114%) within and between individual fecal droppings from the same pig compared to the total fecal excretion. In conclusion, single random samples could not be used to reliably quantify the total fecal concentration or excretion of CICM or IgA in pigs. Analyses of all feces collected during shorter periods than 24 h did not provide an accurate estimate of the daily excretion of CICM. Thus, the concentration of stress sensitive molecules in random single fecal samples as an indicator of animal welfare should be interpreted with prudence.     

Effects of Angular Leaf Spot and Rust on Yield Loss of Phaseolus vulgaris

ABSTRACT Three field experiments were conducted in 1997, 1998, and 1999 to investigate the effects of angular leaf spot and rust, separately or combined, on host growth and yield of individual bean plants (Phaseolus vulgaris). In each experiment, three treatments were established by inoculating cv. Carioca with Phaeoisariopsis griseola, Uromyces appendiculatus, or with both pathogens. An additional control treatment was not inoculated, but was sprayed with a fungicide. In the 1997 and 1999 experiments, angular leaf spot reached higher disease levels than rust, whereas in 1998, rust was more severe than angular leaf spot. Host growth, expressed as healthy leaf area duration (HAD), and yield were the highest in 1997 and lowest in 1998. In each experiment, the treatments did not differ significantly to the area under leaf area progress curve, HAD, and healthy leaf area absorption (HAA). All inoculated treatments had significantly more severe disease and less yield than the control treatment. Based on the analysis of 60 plants in each experiment, yield was not related to the areas under disease progress curve for either or both diseases. In 1997 and 1999, yield was related to HAD (R(2) = 0.57 and 0.43) and HAA(R(2) = 0.60 and 0.55). Based on the combined analysis of all 36 plots, angular leaf spot reduced the leaf area because of defoliation, whereas rust did not affect the leaf area. Rust reduced yield more than four times that of angular leaf spot, although the decrease in photosynthesis to angular leaf spot was twice that of rust.     

Yield loss in chickpeas in relation to development of fusarium wilt epidemics

ABSTRACT Development of 108 epidemics of Fusarium wilt of chickpea caused by Fusarium oxysporum f. sp. ciceris were studied on cvs. P-2245 and PV-61 in field microplots artificially infested with races 0 and 5 of F. oxysporum f. sp. ciceris in 1986 to 1989. Disease progression data were fitted to the Richards model using nonlinear regression. The shape parameter was influenced primarily by date of sowing and, to a lesser extent, by chick-pea cultivars and races of F. oxysporum f. sp. ciceris. Fusarium wilt reduced chickpea yield by decreasing both seed yield and seed weight. These effects were related to sowing date, chickpea cultivar, and virulence of the prevalent F. oxysporum f. sp. ciceris race. Regression models were developed to relate chickpea yield to Fusarium wilt disease intensity with the following independent variables: time to initial symptoms (t(is)), time to inflection point (t(ip)) of the disease intensity index (DII) progress curve, final DII (DII(final)), standardized area under DII progress curve (SAUDPC), and the Richards weighted mean absolute rate of disease progression (rho). Irrespective of the chickpea cultivar x pathogen race combination, the absolute and relative seed yields decreased primarily by delayed sowing. The relative seed yield increased with the delay in t(is) and t(ip) and decreased with increasing DII(final), SAUDPC, and rho. A response surface as developed in which seed yield loss decreased in a linear relationship with the delay in t(is) and increased exponentially with the increase of rho.     

Introduction of new traits into cotton through genetic engineering: insect resistance as example

The main goal of gene transfer into cotton is the development of insect-resistant varieties. The stakes are important since cotton protection against insects uses almost 24% of the world's chemical insecticides market, which is not without consequences on the environment. The first approach was to introduce and express in the cotton genome, genes from the bacterium Bacillus thuringiensis (B.t.) which produces entomopathogenic toxins. The development of an efficient Agrobacterium tumefaciens mediated transformation system was the first step. The expression of B.t. genes was studied and synthetic genes more adapted to a plant genome have been constructed. Studies on their expression in cotton is underway. The second focus was to develop strategies that would minimize the risks of inducing insect resistance. The main approach is to associate several genes coding for entomopathogenic proteins with different modes of action. Genes encoding protease inhibitors were chosen. One possibility is to associate a B.t. gene and a gene encoding a protease inhibitor. Several protease inhibitors were tested in artificial diets on major pests of cotton. The corresponding genes have been introduced into the cotton genome. These various orientations of the research program will be presented. This revised version was published online in July 2006 with corrections to the Cover Date.     

Improved method to track chlorophyll degradation

An analytical method capable of identifying >30 chlorophyll-related compounds in plant extracts has been developed. The method employs liquid chromatography coupled to UV-vis, MS, and MS/MS detection. It can be applied without modification to analyze natural chlorophyll degradation products and other metalloporphyrines. It was successfully applied to identify chlorophyll derivatives found in rehydrated spinach powder and conventionally canned and Veri-Green-processed beans. In the Veri-Green-processed beans several degradation products were identified that are zinc-containing analogues to the chlorophyll derivatives found in vegetables after conventional canning. They have been characterized by liquid chromatography and mass spectrometry.     

A facial recognition tool and legislative changes for improved enforcement of the CITES Appendix II listing of the humphead wrasse,Cheilinus undulatus

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Short-season cotton (Gossypium hirsutum) may be a suitable response to late planting in sub-Saharan regions

In Cameroon, seed cotton yields have not increased over the last 20 years because of the shortening of the rainy season and the worsening socioeconomic context. Farmers consequently often delay planting their crops. The main objective of this study was to investigate whether local indeterminate long-season cottons, grown at the recommended density, were more consistent with the farmers’ current constraints than determinate short-season cultivars from Latin America that could be sown more densely. We carried out a 3-year three-location survey in northern Cameroon, which included two planting dates (recommended and delayed) and two planting densities (recommended and high). We show that these three factors acted independently. Late planting had a highly negative impact on most traits at both plant and plot scale by delaying flowering, reducing seed cotton yield and fibre quality. Dense sowing mainly had an impact on individual plant traits by reducing boll retention and elongating main-stem internodes. Local cultivars have already evolved favourably (enhanced earliness, yield performance, harvest index, ginning out-turn, and fibre maturity) and could be improved further by crossing with highly determinate cottons. However, such a strategy requires further investigation to ensure that a more determinate growth pattern would not have a negative impact on the adaptive response of the traditional cotton plant to other adverse conditions.     

Dietary replacement of fish meal by defatted and fermented soybean meals with taurine supplementation for pompano fish: effects on growth performance,nutrient digestibility,and biological parameters in a long-term feeding period

A 16-wk growth trial was conducted to examine the effects of dietary replacement of fish meal by defatted soybean meal (SBM) and fermented soybean meal (FSBM) with taurine supplementation on growth performance, nutrient apparent digestibility coefficient (ADC) and biological parameters of pompano fish. The FSBM was produced by fermenting SBM with Lactobacillus spp. Seven isonitrogenous and isoenergetic diets were formulated to replace 35% or 50% of fish meal by SBM or FSBM with taurine supplementation. The diets are denoted as follows: FM, SBM35, SBM35T, FSBM35T, SBM50, SBM50T, and FSBM50T. The FM (the basal diet) contained fish meal as a main source of dietary protein. Taurine was supplemented to SBM35T, FSBM35T, SBM50T, and FSBM50T at the level of 15 g/kg diet. Pompano juveniles with an initial body weight (BW) of 80 g reared in floating net cages were fed the experimental diets twice daily for 16 wk. Results showed that the final BW, weight gain, and feed conversion ratio of fish fed SBM35 and SBM50 were significantly lower than those of fish fed FM (P < 0.05), indicating that the replacement of fish meal by SBM at the rate of 35% in the diet is excessive for pompano. Supplementation of taurine to the SBM-included diets significantly increased growth performance and feed utilization (P < 0.05); however, these diets did not restore the performance back to a level equivalent to that of fish offered the basal diet. Meanwhile, fish fed FSBM35T had comparable growth and feed performances to those fed FM. Hematocrit values, total biliary bile acid levels, whole body lipid contents, and tissue taurine concentrations of fish fed SBM35 and SBM50 were the lowest among the treatments, but these parameters were improved by taurine supplementation and FSBM inclusion in the diet. Taurine supplementation increased lipid ADC, and SBM fermentation slightly enhanced both lipid and protein ADCs of the fish. These findings suggest that the combination of FSBM and taurine supplementation is an effective way to improve growth performance, nutrient digestibility, and biological parameters, and that FSBM with taurine supplementation can replace 35% of fish meal in pompano diets without any negative effects on growth and feed performances in a long-term feeding period.     

Plum pox virus: diagnosis and spread inhibition by weed control

Journal of Plant Diseases and Protection - Plum pox virus (PPV) is a plant virus (genus Potyvirus, family Potyviridae) infecting stone fruit trees. Since the first report from Bulgaria in 1917, PPV...     

Field release of a non-toxigenic Aspergillus flavus L strain in central Benin

Journal of Plant Diseases and Protection - Non-toxigenic strains of Aspergillus flavus (Link) can be used as biological control agents to reduce the contamination of grains such as maize with...