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141.
Francesco Carimi Francesco Mercati Roberto De Michele Maria Carola Fiore Paolo Riccardi Francesco Sunseri 《Genetic Resources and Crop Evolution》2011,58(7):967-975
The Sicilian grape cultivar ‘Nero d’Avola’ is among the oldest and most cultivated in the island, taking part in the production
of several red wines exported worldwide, including DOC wines (Etna Rosso and Cerasuolo di Vittoria). Due to the ancient origin
and repeated clonally propagation of the cultivar, phenotypic variability has been observed. Clone identification in this
important cultivar has so far relied on phenotypic and chemical traits analyses, often affected by environmental conditions.
Genetic markers, such as microsatellites, are particularly useful for cultivar identification, parentage testing, pedigree
reconstruction and population structure studies. In the present paper, microsatellites were used to analyze the intra-varietal
genetic diversity among 118 plants of ‘Nero d’Avola’, collected in 30 vineyards displaced in different areas of Sicily. Out
of 22 microsatellites, 11 showed polymorphism among samples and 15 different phylogenetic groups were identified. Results
show that ‘Nero d’Avola’ actually comprises different genetic profiles, although most of clones share a common origin. 相似文献
142.
Alessandra Lagomarsino Anna Benedetti Sara Marinari Letizia Pompili M. Cristina Moscatelli Pier Paolo Roggero Roberto Lai Luigi Ledda Stefano Grego 《Biology and Fertility of Soils》2011,47(3):283-291
Five soils characterised by different agro-forest managements, typical of Mediterranean environment and with increasing human
impact were chosen in Sardinia (Italy): two vineyards with different management systems, a rotation hay crop-pasture and a
forest (Quercus suber L.). The study aimed to investigate the relationships between C storage and microbial functionality in soil under different
managements. Pools of total organic C and microbial biomass C were determined, as well as the loss of organic C due to microbial
respiration (basal and cumulative) and several microbial indices (metabolic, mineralization, and microbial quotient) as indicators
of the microbial efficiency in the use of energy and the degree of substrate limitation for soil microbes. Enzymes were chosen
on their relevance in the C (β-cellobiohydrolase, N-acetyl-β-glucosaminidase, β-glucosidase, α-glucosidase), N (leucine aminopeptidase), S (arylsulphatase) and P (acid phosphatase)
cycling and were used as indicators of functional diversity in soil. Organic C pools and enzyme activities on average increased
noticeably in soils with a lower human impact showing the highest values in forest and the lowest in the vineyards, following
the trend of organic matter availability. The trend in functional diversity reflected the increase of microbial pool and organic
C availability: the vineyards showed a lower Shannon’s diversity index, whilst pasture and forest sites reached the maximum
levels of functional diversity. These soils showed an increase of microbial efficiency in the use of available resources and
the decrease of substrate limitation for soil microbes. 相似文献
143.
144.
145.
Guglielmo Lione Luana Giordano Fabiano Sillo Francesca Brescia Paolo Gonthier 《Plant pathology》2021,70(9):2016-2033
Two chestnut (Castanea sativa) orchards of north-western Italy were sampled with passive spore traps 35 times over 24 months. Samples were analysed through a newly developed quantitative PCR assay to quantify propagule loads of the emerging fungal pathogen Gnomoniopsis castaneae. Average propagule deposition patterns were assessed along with temporal and climatic variables, including sampling month and season, temperatures, relative humidity, precipitations, and wind. Machine learning algorithms combining information theory, fractal analysis, unbiased recursive partitioning, ordinary least squares and logistic regressions, were used to model propagule deposition patterns. The trained models were validated on independent data gathered from 24 samplings conducted in a third chestnut orchard during the same timeframe. Results showed that propagule deposition rate (DR) was variable within and among sites, with a site average ranging from 173 to 765 spores ⋅m−2 ⋅h−1. Propagule deposition was observed across all seasons, although the DR dropped substantially during wintertime (p < 0.05). Mean, maximum, and minimum temperatures, the growing degree days at 0 and 5℃ thresholds, and wind gust were all positively correlated (p < 0.05) with DR of G. castaneae. The trained models were all significant (p < 0.05), as well as their validation (p < 0.05). Fluctuations of propagule deposition throughout the year were consistent among sites and proved to be driven by temperatures. Wind gust was associated with the overall amount of propagules deposited at site level. In future, the increase in temperatures and strong winds as a result of climate change may boost the spread of G. castaneae. 相似文献
146.
Paolo Fantozzi Alessandro Sensidoni 《Plant foods for human nutrition (Dordrecht, Netherlands)》1983,32(3-4):351-368
The goals of the present studies were: (1) to obtain smoking material from tobacco with reduced toxicity; (2) to use the tobacco leaf, as an alternative to other plants, as a source of food protein. On the grounds of technological, nutritional and agronomical results, the following observations can be made: (1) It is feasible to lower the toxicity of the tobacco smoke by extracting protein from the green leaves before curing. (2) The cured deproteinized tobacco can easily be utilized for the production of smoking material without any important alteration of its taste. (3) The composition of the tobacco protein concentrate is very interesting and is superior to other protein concentrates. (4) Itsin vivo andin vitro digestibility is one of the highest among the vegetable protein sources which have been studied. (5) Use of high planting densities and high levels of nitrogen fertilization per hectare results in high yields of total protein from tobacco (1794 Kg/ha). 相似文献
147.
The effects of (S)-(+)-carvone treatments on seed potato tuber dormancy and sprouting 总被引:1,自引:0,他引:1
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
148.
Paolo Cerletti Marcello Duranti Patrizia Restani 《Plant foods for human nutrition (Dordrecht, Netherlands)》1983,32(2):145-154
Composition, solubility, bound sugar content and quality, subunit composition and structure of the storage proteins of seeds ofLupinus albus are discussed. Aminoacid composition is also given for each protein, the various protein classes and the whole flour. These data allow for the characterization of the molecules of the various storage proteins and their contributions to the nutritional properties of the seed.In vitro digestibility (by mammalian endopeptidases) is reported and is less than for animal proteins. Possible causes, at the molecular level, for this behaviour and possible means to overcome these effects are examined. The relationships between the above data are considered in view of the nutritional performance of the proteins and of the genetical, agronomic and technological approaches most suited to improve the nutritional quality of lupine seeds as a protein source. 相似文献
149.
Yield response of corn to irrigation and nitrogen fertilization in a Mediterranean environment 总被引:1,自引:0,他引:1
Productivity and resource-use efficiency in corn (Zea mays L.) are crucial issues in sustainable agriculture, especially in high-demand resource crops such as corn. The aims of this research were to compare irrigation scheduling and nitrogen fertilization rates in corn, evaluating yield, water (WUE), irrigation water (IRRWUE) and nitrogen use (NUE) efficiencies. A 2-year field experiment was carried out in a Mediterranean coastal area of Central Italy (175 mm of rainfall in the corn-growing period) and corn was subjected to three irrigation levels (rainfed and supply at 50 and 100% of crop evapotranspiration, ETc) in interaction with three nitrogen fertilization levels (not fertilized, 15 and 30 g (N) m−2). The results indicated a large yearly variability, mainly due to a rainfall event at the silking stage in the first year; a significant irrigation effect was observed for all the variables under study, except for plant population. Nitrogen rates affected grain yield plant−1 and ear−1, grain and biomass yield, HI, WUE, IRRWUE and NUE, with significant differences between non-fertilized and the two fertilized treatments (15 and 30 g (N) m−2). Furthermore, deficit irrigation (50% of ETc) was to a large degree equal to 100% of the ETc irrigation regime. A significant interaction “N × I” was observed for grain yield and WUE. The effect of nitrogen availability was amplified at the maximum irrigation water regime. The relationships between grain yield and evapotranspiration showed basal ET, the amount necessary to start producing grain, of about 63 mm in the first and 206 mm in the second year. Rainfed crop depleted most of the water in the 0–0.6 m soil depth range, while irrigated scenarios absorbed soil water within the profile to a depth of 1.0 m. Corn in a Mediterranean area can be cultivated with acceptable yields while saving irrigation water and reducing nitrogen supply and also exploiting the positive interaction between these two factors, so maximizing resource-use efficiency. 相似文献
150.
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