1,720,988 research outputs found
Suscettibilità al Bacillus thuringiensis Berliner in relazione allo sviluppo di Ostrinia nubilalis Hübner (Lepidoptera Crambidae)
No full textStudies on the effects of Bt corn expressing CryIAb on two parasitoids of Ostrinia nubilalis Hb. (Lepidoptera: Crambidae)
No full textPrime indicazioni sulla nematofauna dei vigneti in un comprensorio viticolo del Piemonte
No full textLe piante storiche in Lombardia : Manuale delle avversità, come riconoscerle, prevenirle e curarle
No full textThe performance of Macrosiphoniella millefolii and Myzus persicae on Achillea collina
No full textThis paper compares the development of the polyphagous aphid Myzus persicae Sulzer, considered as a generalist, and the oligophagous aphid Macrosiphoniella millefolii (De Geer), considered as a specialist, on yarrow (Achillea collina Becker ex Reichenbach). Yarrow is a medicinal plant rich in bioactive secondary metabolites that have possible effects on the development of phytophages, including aphids. Age specific life tables for cohorts developing under different constant temperatures were constructed and analyzed using standard techniques, and complemented with Jackknife estimates of the intrinsic rate of increase and its standard error. The parthenogenetic wingless morphs of the two species differed in the immature developmental time and survival, and in adult fecundity and life span. At high temperatures, the intrinsic rate of increase as the overall metric of performance tended to be higher for the generalist than for the specialist aphid species, while the opposite appears to occur at low and medium temperatures. Further insight into the complex interactions between yarrow and aphids requires that their genetic diversity is taken into account. The study of yarrow-aphid-natural enemy population interactions requires additional information on biomass dynamics, aphid morph differentiation and the performance of biological control agents
Insect community structure and insect biodiversity conservation in an Alpine wetland subjected to an intermediate diversified management regime
No full textThe paper deals with the structure of insect communities and insect biodiversity conservation in the
Alpine wetland of Pian Gembro (Italy). For over a century, the wetland was subjected to diversified peat
harvesting procedures, to agricultural exploitation and recently, to a superimposed diversified intermediate
management regime (DIMR) aiming at plant species and plant diversity conservation. The purpose
of this paper is to evaluate whether the DIMR is likewise effective for insect biodiversity conservation.
Pitfall traps, sweep and collections of visually observed insects yielded 997 individuals representing 141
species from 11 insect families. The rank-frequency curve for bog insects was relatively steep indicating
a low evenness due to the high abundance of low ranking species. The curve for insects collected in the
surroundings was less steep pointing to a relatively high evenness due to a lower abundance of low
ranking species. In both the bog and the surroundings the Shannon diversity index was generally highest
at intermediate levels of disturbance. These results indicate that the DIMR strategies implemented for
plant biodiversity conservation is also appropriate to conserve insect species biodiversity
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