Communications in agricultural and applied biological sciences最新文献

The objective of this study was to develop an alternative strategy for the control of Spodoptera litura larvae by using botanical insecticides. Rhizomes of Alpinia galanga were extracted with hexane, dichloromethane, ethyl acetate and methanol, respectively. Each crude extract was examined for toxicity against the second instars of S. litura according to a topical application method. The dichloromethane extract was found to show the highest toxicity of all the extracts, with LD50 = 3177 and 2099 ppm at 24 and 48 h post-treatment, respectively.

Triticale is grown in Romania, mainly, in the hilly regions on the acid poor fertile soils and covers, yearly, around 100-130 thousands ha or 1.5% from the arable land. Since 1971, when the breeding program has been started, up to present, it has been developed an adapted triticale germplasm for the Romanian environmental conditions and 12 new varieties have been registered. Genetic progress for yield, estimated over a 27 years, is by 46 kg ha(1) year(1) or 0.80% year(1), similarly with those realized in the most dynamic triticale breeding programs of the world. The improving of yields has been achieved by an increased number of kernels per spikes, plumpness of kernels, test weight and reduction of the plant height by introduction in the Romanian triticale germplasm of RhtB1b (Rht1) and Ddw1 (Hl) genes. The genetic gain for reduction of plant height, in this period, was estimated at 1.16 cm yr(1). Further progress regarding yield stability under conditions of global climatic changes, a broader genetic diversity for preharvest sprouting (PHS), drought tolerance, earliness, high canopy albedo, diseases resistance, especially for fusarium head blight (low DON content in kernels), leaf rust and BYDV, is required.

The promotion of renewable energy represents a target of the European 2020 strategy for economical growth and sustainable competitiveness. Cereals are considered a promising biomass producing crop in temperate regions of Europe to be used for both fuel alcohol and biogas production. Among cereals, triticale represents a good candidate for this kind of application, showing a number of advantages such as high grain yield even in marginal environments, tolerance to drought, tolerance to more acid soils, lower production costs and lower susceptibility to biotic stresses. The aim of this study was to compare yield and quality of eight triticale lines grown in marginal areas in a two-year experiment. Italian variety, Magistral, and a bread wheat variety (EW9) were selected for comparison. Data from fields, chemical analyses and preliminary results from fermentation are reported.

Global increases in human population are creating an ever-greater need for food production. Poor soil management practices have degraded soil to such an extent that rapidly improved management practices is the only way to ensure future food demands. In South Africa, deciduous fruit producers are realising the need for soil health, and for an increased understanding of the benefits of soil ecology, to ensure sustainable fruit production. This depends heavily on improved orchard management. Conventional farming relies on the addition of artificial fertilizers, and the application of chemicals, to prevent or minimise, the effects of the soil stages of pest insects, and of plant-parasitic nematodes. Currently, there is resistance toward conventional farming practices, which, it is believed, diminishes biodiversity within the soil. The study aimed to establish the soil nematode community structure and function in organically, and conventionally, managed deciduous fruit orchards. This was done by determining the abundance, the diversity, and the functionality of the naturally occurring free-living, and plant-parasitic, nematodes in deciduous fruit orchards in the Western Cape province of South Africa. The objective of the study was to form the basis for the use of nematodes as future indicators of soil health in deciduous fruit orchards. Orchards from neighbouring organic, and conventional, apricot farms, and from an organic apple orchard, were studied. All the nematodes were quantified, and identified, to family level. The five nematode-classified trophic groups were found at each site, while 14 families were identified in each orchard, respectively. Herbivores were dominant in all the orchards surveyed. Organic apples had the fewest herbivores and fungivores, with the highest number of carnivores. When comparing organic with conventional apricot orchards, higher numbers of plant-parasitic nematodes were found in the organic apricot orchards. The Maturity Index (MI) indicated that all orchard soils had values below 1.5, indicating disturbed conditions. The conventionally managed apricot orchard had the highest MI value, of 1.48. The Plant Parasitic Index (PPI) value was highest in the organically managed apricot orchard. In order to determine the existing enrichment, structural, and basal conditions, the nematode faunal analysis was applied to each site. All the sites indicated enriched and structured conditions. Regarding the diversity, the richness, and the evenness of the distribution, soil from the conventional apricot orchard had the highest species richness, whereas the organic apple orchard soil had the most even distribution of families. Different management practices in fruit orchards did not show marked differences in terms of community composition and structure.

The first series of field experiments with triticale F1 hybrids from 2009 confirmed usefulness of the rye 'Pampa' cytoplasmic system of mass crossing control in hexaploid (2n = 42 = AABBRR) winter triticale. The level of fertility restoration in 30 F1 hybrids varied within a range of 35.1% - 91.3%. However, the top F1 yield has not exceeded 92% of the check cultivar 'Moderato'. In the next series of field experiments with four winter F1 hybrids from 2012 the best yield reached 102% of the 'Moderato' standard and the fertility restoration index ranged between 16.7% and 100%. The top yielding F1 combination was produced using a male line derived from a cross with a restorer line from rye hybrid breeding. It supports the idea of using rye hybrid breeding as a source of variation in hybrid breeding of triticale. The advanced rye lines, representing well established complementary gene pools, show not only high potential for heterosis, but also high level of compensation for negative side effects of the 'Pampa' cytoplasm on plant vigor, which seems important in triticale. The gene flow from rye female and male gene pools to those of hexaploid triticale is facilitated with tetraploid triticale x diploid rye crosses. Numerous triploid F1 hybrids with relatively high fertility are produced, which are able to set seed after spontaneous pollination with hexaploid triticale.

During five subsequent growing seasons field experiments were carried out at the experimental farm of the University College Ghent (Belgium) to evaluate the selectivity and efficacy of herbicides for chemical weed control in triticale (x Triticosecale Wittmack). The experiments were set up on a sandy loam soil, according to a completely randomised block design with four replications. Several herbicides and combinations of herbicides were applied pre- and post-emergence, at different rates. The influence of the different treatments on weed diversity, weed density, growth inhibition and chlorosis of the crop and grain yield was studied. Results obtained from these field trials indicated differences between the different treatments.