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121.
A pea breeding strategy is required to cope with the large climatic variation featuring south-European environments. Thirty-seven recent cultivars bred by 21 European or Australian institutions were grown in two climatically contrasting Italian sites (Lodi, subcontinental; Foggia, Mediterranean), two cropping years per site and two sowing times per year, to define various elements of this strategy. The study assessed: (i) the impact of genotype × environment (GE) interaction due to spatial and temporal factors on the consistency of top-yielding cultivars; (ii) the similarity between environments for GE effects and its implications on adaptation strategies; (iii) the extent of genotypic and GE interaction effects, and the relationship with adaptive responses, for various morphophysiological traits; (iv) the adaptation pattern and the combination of adaptive traits featuring three germplasm types, i.e. European spring and winter types, and germplasm selected in Mediterranean environments; (v) the predicted efficiency of direct and indirect selection procedures for grain yield. The geoclimatic area had a major impact on crop yield (5.15 t/ha in Lodi vs. 2.52 t/ha in Foggia) but tended to affect GE interaction less than time or year of autumn sowing, suggesting to breed for wide adaptation. Top-yielding cultivars as modeled by additive main effects and multiplicative interaction were environment-specific. On average, spring and winter materials outyielded the Mediterranean germplasm but the spring type, characterized by wide entry variation, included most widely- and specifically-adapted top-yielding cultivars. Cold-tolerant spring-type germplasm is preferable to breed for wide adaptation as it may combine high yield potential with adaptation to winter cold and terminal drought and heat stress. Lodging susceptibility, harvest index, onset and duration of flowering, and canopy height at maturity assessed in individual environments showed moderate to fairly high broad-sense heritability on a plot basis (h2 > 0.20) and tended to correlation with yield over test environments (r ≥ 0.20). An indirect selection index including harvest index and canopy height exhibited about 20% greater predicted efficiency than direct selection for yield when using one selection environment and could be preferred for early selection stages. Direct yield selection in late selection stages should ideally be performed across 2 years in two environments that contrast for geoclimatic area and time of autumn sowing.  相似文献   
122.
Summary Potato seed tubers may suffer from premature sprouting during storage, thus limiting their suitability for cultivation. Commonly used sprout suppressant treatments negatively affect but viability and therefore a reliable method to inhibit bud development must still be found for seed tubers. The monoterpene carvone ((S)-(+)-carvone) was tested in small scale experiments. The vapour of this compound fully inhibited bud growth of tubers cv. Monalisa stored at 23°C without affecting bud viability throughout 6 months of treatment. The most effective range of carvone vapour concentrations was between 0.34 and 1.06 μmol mol−1. With these qualities we can expect carvone to become a suitable sprout suppressant for seed tubers.  相似文献   
123.
The spectrum of water vapor is of fundamental importance for a variety of processes, including the absorption and retention of sunlight in Earth's atmosphere. Therefore, there has long been an urgent need for a robust and accurate predictive model for this spectrum. In our work on the high-resolution spectrum of water, we report first-principles calculations that approach experimental accuracy. To achieve this, we performed exceptionally large electronic structure calculations and considered a variety of effects, including quantum electrodynamics, which have routinely been neglected in studies of small many-electron molecules. The high accuracy of the resulting ab initio procedure is demonstrated for the main isotopomers of water.  相似文献   
124.
The mechanisms that determine how folding attempts are interrupted to target folding-incompetent proteins for endoplasmic reticulum-associated degradation (ERAD) are poorly defined. Here the alpha-mannosidase I-like protein EDEM was shown to extract misfolded glycoproteins, but not glycoproteins undergoing productive folding, from the calnexin cycle. EDEM overexpression resulted in faster release of folding-incompetent proteins from the calnexin cycle and earlier onset of degradation, whereas EDEM down-regulation prolonged folding attempts and delayed ERAD. Up-regulation of EDEM during ER stress may promote cell recovery by clearing the calnexin cycle and by accelerating ERAD of terminally misfolded polypeptides.  相似文献   
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  • 1. Spatio‐temporal distribution and anthropogenic mortality factors were investigated in loggerhead turtles (Caretta caretta) found stranded or floating in the waters around Italy. A total of 5938 records for the period 1980–2008 were analysed concerning loggerhead turtles measuring from 3.8 to 97 cm curved carapace length (mean: 48.3 cm).
  • 2. Results highlighted the following conservation issues: (i) in the study area, anthropogenic mortality is higher than natural mortality; (ii) interaction with fisheries is by far the most important anthropogenic mortality factor; (iii) longlines are an important mortality factor in the southern areas; (iv) trawlers are the cause of high numbers of dead strandings in the north Adriatic; (v) entanglement in ghost‐gear or in other anthropogenic debris affects high numbers of turtles; and (vi) boat strikes are an important source of mortality in most areas but mostly in the warm seasons.
  • 3. Results also indicate that: (vii) the north Adriatic is the area with the highest turtle density; and (viii) the south Adriatic and to a lesser extent the surrounding areas of the north Adriatic and the Ionian, are important developmental areas for loggerhead turtles in the first years of life.
  • 4. Italy is in the centre of the Mediterranean Sea and borders major foraging areas for the loggerhead turtles in the region, and these results confirm previous concerns about the level of anthropogenic mortality in Italian waters. Copyright © 2010 John Wiley & Sons, Ltd.
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128.
The state of demersal fishery in the Southern Adriatic Sea (GFCM-GSA 18, Central Mediterranean), years 1996–2003, from a biological, social and economic point of view was analysed using 47 indicators: 22 biological indicators obtained from fishery-independent data through yearly experimental bottom trawl surveys (“Medits” Programme), and 25 socio-economic indicators estimated from fishery-dependent data, available from the monitoring system of the Italian Institute for Economic Research on Fisheries and Aquaculture (IREPA). Biological indicators were applied for “single-species” (Eledone cirrhosa, E. moschata, Illex coindetti, Merluccius merluccius, Mullus barbatus, Nephrops norvegicus, Parapenaeus longirostris, Raja clavata, Zeus faber) and for “multi-species” analysis. Economic indicators describing economic performance, productivity, costs and prices, and the overall economic sustainability of fishery were estimated. Social indicators and a general indicator summarising social sustainability were also considered. Indicators’ values were displayed using the Traffic Light system. Both fishery-independent and fishery-dependent indicators highlighted a progressive decline of the trawl fishery system in the GSA 18. This decline was mainly related to the ongoing depletion of the traditional fishery target species (mostly long-living, late-maturing species) partially replaced by the increase of traditional accessory species (generally short-living species), as well as to the reduction of productivity and increasing costs. The whole procedure was proposed as a contribution to the identification and applicability of bio-economic indicators for fishery management purposes.  相似文献   
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