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Commercial Cultivation (commercial + cultivation)
Selected AbstractsDeterminants of Voter Support for a Five-Year Ban on the Cultivation of Genetically Modified Crops in SwitzerlandJOURNAL OF AGRICULTURAL ECONOMICS, Issue 3 2008Felix Schläpfer D62; D72; Q26 Abstract While much effort has been devoted to estimating market premiums for non-genetically modified (GM) food, the results of such research are largely silent about the preferences for the public good aspects, or externalities, of GM food production. For public goods, the closest substitute of private consumption decisions is voting on referenda. In November 2005, 55.7% of 2 million Swiss voters approved a five-year moratorium (ban) on the commercial cultivation of GM plants in Switzerland. The present study examines how individual voting decisions were determined by: (i) socioeconomic characteristics; (ii) political preference/ideology; and (iii) agreement with a series of arguments in favour and against the use of GM plants in Swiss agriculture. The analysis is based on the data of the regular voter survey undertaken after the national-level voting in Switzerland. The results suggest that current concerns about the use of genetically engineered plants in agriculture may not automatically decrease with higher levels of education/knowledge and generational change. Furthermore, analysis of voter motives suggests that public support for a ban on GM crops may be even larger in other countries, where industrial interests in crop biotechnology are less pronounced. [source] An approach for post-market monitoring of potential environmental effects of Bt -maize expressing Cry1Ab on natural enemiesJOURNAL OF APPLIED ENTOMOLOGY, Issue 4 2009O. Sanvido Abstract Post-market monitoring (PMM) consistent with Swiss and European Union legislation should ensure the detection and prevention of adverse effects on the environment possibly deriving from commercial cultivation of genetically modified (GM) crops. Insect-resistant GM crops (such as Bt -maize) raise particular questions regarding disturbances of biological control functions provided by beneficial insects such as predators and parasitoids (so-called natural enemies). Consensus among regulators, scientists and the agricultural biotech industry on appropriate PMM plans allowing the detection and possibly prevention of such adverse effects is still lacking. The aims of this study were to identify the necessity for PMM of Bt -maize expressing Cry1Ab on natural enemies and to develop an appropriate PMM plan. The approach chosen consisted in determining what type of monitoring is most appropriate to address potential effects of Bt -maize on natural enemies during commercial cultivation. This included identifying whether there remain substantial scientific uncertainties that would support case-specific monitoring. Existing pre-market risk assessment data indicate that Bt -maize (Cry1Ab) comprises a negligible risk for disturbances in biological control functions of natural enemies. As a consequence, a faunistic monitoring of specific groups of natural enemies is not considered an appropriate approach to detect failures in biological control functions. Alternatively, an approach is proposed that consists in indirectly analysing biological control functions by surveying outbreaks of maize herbivores. Unusual herbivore outbreaks could indicate failures in biological control functions of natural enemies. Data could be collected via questionnaires addressed to farmers growing Bt -maize. Significant correlations between unusual occurrences of specific maize herbivores and the cultivation of Bt -maize would subsequently need specific studies to determine possible causalities in more detail. The here proposed approach has the advantage of covering different natural enemy groups. It represents a cost-effective strategy to obtain scientifically sound data as a basis for regulatory decision-making. [source] Biochemical Changes in Leaf Tissues of Taro [Colocasia esculenta L. (Schott)] Infected with Phytophthora colocasiaeJOURNAL OF PHYTOPATHOLOGY, Issue 3 2010Manas Ranjan Sahoo Abstract The changes in some biochemical parameters due to Phytophthora leaf blight infection were assessed in leaf tissues of one resistant (DP-25), two moderately resistant (Duradim and Jhankri) and one susceptible (N-118) genotypes of taro [Colocasia esculenta (L.) Schott]. Phytophthora spore suspension (15 000 spore/ml water) was sprayed onto the in vitro raised taro plantlets at 30 days after establishment in pots to induce disease. In comparison with the uninoculated leaves, blight infected leaves showed reduction in protein content and activity of nitrate reductase and increase in total soluble sugar, reducing sugar content and activities of acid phosphatase and alkaline phosphatase among the studied genotypes. Changes in biochemical parameters under induced blight stress as compared with uninoculated control were less in resistant genotypes than that in susceptible genotype. The deviations in biochemical contents were highest in susceptible genotype N-118. Based on the variations of above parameters under stress and non-stress control among the four tested genotypes, the overall pattern of changes was N-118 > Duradim > Jhankri > DP-25, which is in accordance with the pattern of increasing resistance. The resistant genotypes could be used for commercial cultivation and genetic improvement programme to develop resistant varieties to Phytophthora leaf blight disease. [source] Mass Production of Juveniles of the Fat Snook Centropomus parallelus in BrazilJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2002Luis Alvarez-Lajonchegre A pilot-scale trial to rear fat snook Centropomus parallelus through larval, weaning and nursery phases was conducted in Florianópolis, Brazil. Eggs (96% fertilization) from captive broodstock, induced to spawn using 50 ,g/kg LHRHa were stocked in two 4,000-L cylindrical fiberglass tanks at a mean density of 19.2 eggs/L. Nannochloropsis oculata was stocked with the eggs and maintained at a mean density of 0.5,1.0 ± 106 cells/mL up to 31 dph (31 dph). Hatching averaged 90%. Larvae were fed rotifers Brachionus rotundiformis enriched with an oil emulsion from 3 dph to 36 dph (30,40 rotifers/mL) and Artermia meta-nauplii enriched with Selco from 22 dph to 60 dph (mean 2.9 meta-nauplii/mL). Weaning began at 45 dph with an artificial dry diet NRG (50% protein), supplied together with concentrated and enriched Artemia meta-nauplii. No critical period of mortality was observed during larval rearing. During the 43 days of weaning and nursery, less than 1% mortality was recorded. Food conversion rate during nursery was 1.17, with a change in the coefficient of variation of mean total length of 1.3%. Specific total growth rate in weight was 13.0 %/d and mean growth in total length and total weight were 0.65 mm/d and 24.0 mg/d over the whole rearing trial respectively. Mean total length and total weight of juveniles were 57.6 ± 0.1 mm and 2.11 ± 0.12 g, respectively, and the length-weight relationship was W = 8.29931 ± 10,5 TL3.049607 (r= 0.9986). on 88 dph when the trial was terminated. The condition factor on 88 dph was 1.104. On 88 dph a total of 35,000 juveniles were harvested, overall survival was 25.5% with mean final density of 4.4 fishn and biomass of 6.9 kg/m3. The present trial demonstrated the feasibility of mass production of fat snook. Possible improvements necessary for commercial cultivation of fat snook C. parallelus are discussed. [source] Baseline sensitivity of lepidopteran corn pests in India to Cry1Ab insecticidal protein of Bacillus thuringiensisPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 8 2010Sushil K Jalali Abstract BACKGROUND: Genetically engineered corn (Bt corn) expressing Bacillus thuringiensis Berliner insecticidal protein Cry1Ab is a biotechnological option being considered for management of lepidopteran corn pests in India. As a resistance management practice it was essential to determine the sensitivity of multiple populations of the stalk borer Chilo partellus (Swinhoe), pink borer Sesamia inferens (Walker) and the cob borer Helicoverpa armigera (Hübner) to Cry1Ab protein through bioassays. The insect populations were collected during growing seasons of Rabi 2005 (October 2005 to February 2006) and Kharif 2006 (May to September 2006). RESULTS: Multiple populations of the three lepidopteran corn pests were found to be susceptible to Cry1Ab. Median lethal concentrations (LC50) ranged between 0.008 and 0.068 µg Cry1Ab mL,1 diet for 18 populations of C. partellus (across two seasons), between 0.12 and 1.99 µg mL,1 for seven populations of H. armigera and between 0.46 and 0.56 µg mL,1 for two populations of S. inferens. CONCLUSION: Dose,response concentrations for lethality and growth inhibition have been determined to mark baseline sensitivity of multiple populations of key lepidopteran corn pests in India to Cry1Ab protein. These benchmark values will be referenced while monitoring resistance to Cry1Ab should Bt corn hybrids expressing Cry1Ab be approved for commercial cultivation in India. Copyright © 2010 Society of Chemical Industry [source] Comparative evaluation of exotic and adapted germplasm of spring wheat for floral characteristics in the Indo-Gangetic Plains of northern IndiaPLANT BREEDING, Issue 6 2007S. K. Singh Abstract Four hundred spring wheat genotypes, comprising exotic and indigenous germplasm and adapted cultivars for commercial cultivation, were investigated during four crop seasons for six floral characteristics related to outcrossing behaviour. Genetic variability and heritability were investigated along with phenotypic correlation coefficients among these characteristics. A significant quantitative variation existed among the characteristics in all three groups. High heritability for stigma length, openness of florets, anther extrusion and duration of floral opening indicated that selection for these characteristics may be effective. The adapted cultivars were found more promising than the exotic and indigenous germplasm. Most of the characteristics showed significantly positive correlation with each other and high correlation was observed between anther and stigma length, and anther extrusion and duration of floral opening. Superiority of varietal mixtures and segregating generations (F3 and F4) of two crosses over parental lines suggested that heterozygosity and heterogeneity can provide yield advantages. Germplasm lines possessing superior expression of floral characteristics may be used to improve yielding ability through enhanced heterozygosity or the development of hybrids. [source] A review of methods for Centropomus spp. (snooks) aquaculture and recommendations for the establishment of their culture in Latin AmericaAQUACULTURE RESEARCH, Issue 7 2008Luis Alvarez-Lajonchčre Abstract The positive features of Centropomids and Latids for cultivation are analysed and highlighted. The main life cycle characteristics as well as market prices and demands are presented. Good growth, highly efficient food conversion ratios and energy utilization allow very high biomass yields per unit volume in nursery and grow-out systems. They have shown notable tolerances to main environmental conditions, as well as considerable versatility in adapting to culture systems (cages, ponds and tanks), and culture intensity (extensive, semi-intensive, intensive and superintensive), especially in estuarine and coastal sites and ponds. These positive features provide them with a high culture potential. A general summary of their culture is presented, based on the commercial cultivation of the Asian sea bass or barramundi Lates calcarifer as well as the experimental and pilot-scale results from the main American species. The importance of hatchery fry production as an essential culture pre-requisite is emphasized, in addition to an analysis of the main difficulties and constraints for future development. [source] | |||||||||||||