Insecticide Resistance: Effects of WARF Antiresistant on Toxicity of DDT to Adult Houseflies

Addition of N, N-dibutyl-p-chlorobenzene sulphonamide (Antiresistant/DDT) in amounts equal to one fifth the dose of DDT increased the toxicity of DDT to the DDT-resistant portion of a housefly population. Full susceptibility was not regained. There was no increase in toxicity to the DDT-susceptible portion.     

Marker-assisted increase of genetic diversity in a double-low seed quality winter oilseed rape genetic background

Generation of novel genetic diversity for maximization of heterosis in hybrid production is a significant goal in winter oilseed rape breeding. Here, we demonstrate that doubled haploid (DH) production using microspore cultivation can simultaneously introgress favourable alleles for double‐low seed quality (low erucic acid and low‐glucosinolate content) into a genetically diverse Brassica napus genetic background. The DH lines were derived from a cross between a double‐low quality winter rapeseed variety and a genetically diverse semisynthetic B. napus line with high erucic acid and high glucosinolates (++ quality). Twenty‐three low‐glucosinolate lines were identified with a genome component of 50–67% derived from the ++ parent. Four of these lines, with a genome component of 50–55% derived from the ++ parent, also contained low erucic acid. Heterosis for seed yield was confirmed in test‐crosses using these genetically diverse lines as pollinator. The results demonstrate the potential of marker‐assisted identification of novel genetic pools for breeding of double‐low quality winter oilseed rape hybrids.     

Environmental factors and agronomic practices associated with Savi’s pine vole abundance in Italian apple orchards

Journal of Pest Science - The development of an integrated rodent pest management strategy requires the adoption of protocols that should be based on a good knowledge of species–habitat...     

Vegetable oil formulation as biopesticide to control California red scale (<Emphasis Type="Italic">Aonidiella aurantii</Emphasis> Maskell)

During laboratory tests, mineral oil in water emulsion (2%), containing Brassicaceae seed meals (2 g l⁻¹), induced total mortality (100%) among adult female California red scales on detached orange fruits, whereas only 47.5% of insect mortality was observed with the same mineral oil when used alone. These results were partially confirmed by two preliminary field trials. With the aim of improving biodegradability and the environmental impact of the insecticidal formulation, mineral oil was replaced by a vegetable oil without observing any significant variation of the product’s efficacy. In addition, a clear “dose-effect” of meal in mineral and vegetable oil was also demonstrated. The formulation, essentially based on oil, meals and some minor additives, shows the following advantages: (1) high insecticidal activity against an insect pest difficult to control such as Aonidiella aurantii (Maskell); (2) simultaneous control of several pathogens seems to be possible; (3) non-appearance of resistance phenomena in plant pathogens; and finally, (5) absence of phytotoxicity.     

Characterizing the molecular and morphophysiological diversity of Italian red clover

Red clover (Trifolium pratense L.) is the third major forage species in Europe, but there is limited information on the biodiversity and the genetic structure of landraces and natural populations which evolved in this region. The objective of this study was producing such information for Italian germplasm on the ground of molecular and morphophysiological diversity. The study included 16 Italian natural populations from a wide range of environments, four landraces representing the four traditional commercial ecotypes, and two varieties. Eight morphophysiological traits were assessed in a replicated trial under field conditions, whereas two AFLPs primer combinations with 140 polymorphic markers were recorded on a random sample of 13 genotypes per population. Ordination and classification results based on morphophysiological data clearly kept track of the type of germplasm (i.e. landrace or natural population) and its geographic origin, unlike results based on molecular markers. Euclidean distances among populations based on morphophysiological traits were not correlated with Nei’s genetic distances based on molecular markers according to Mantel’s test. Geographical distances among landrace or natural population material was correlated with distances based on morphophysiological traits but not with those based on molecular markers. The average within-population variation estimated via molecular markers was about 2.6-fold higher than that among populations, preventing an acceptable discrimination among most populations. On average, natural populations tended to have within-population variation similar to varieties and somewhat lower than landraces. Our results have implications for collection, conservation, exploitation and registration in a sui generis system of red clover genetic resources.     

Changes in bacterial and archaeal community assemblages along an ombrotrophic peat bog profile

Biology and Fertility of Soils - Peatlands are archives of extreme importance for the assessment of past ecological, environmental and climatic changes. The importance as natural archives is even...     

Sequence analysis of rDNA intergenic spacer region (IGS) as a tool for phylogenetic studies in Trichoderma spp.

Different from ribosomal genes, which contain highly conserved sequences that are detected in all organisms, the intergenic spacer of rDNA (IGS) appears to be the most rapidly-evolving spacer region. For this reason we tested this region for phylogenetic studies. This report focuses on the study of IGS sequences of isolates belonging to Trichoderma section (T. viride, T. koningii, T. hamatum, T. erinaceus, T. asperellum) and Pachybasium section (T. harzianum, T. crassum, T. fascicu…