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101.
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103.
Eighty-seven Phaseolus vulgaris landraces, still cultivated in Calabria (Italy), were investigated in order to study the patterns of common bean genetic diversity in this region, to better understand the evolutionary development of beans in Europe and to properly manage these genetic resources. Four American accessions and five Italian varieties were also included. Different markers, such as 12 microsatellites, seed traits, phaseolins and 100-seed weight were combined with different statistical approaches. For each microsatellite, expected (H e ) and observed (H o ) heterozygosities, polymorphism information content (PIC), probability of identity (PI) and homozygosity were calculated. Furthermore, in Calabrian group of bean landraces, total (N a ) and private (N pa ) number of alleles, observed (H o ), expected heterozygosities (H e ) and allelic richness (AR) were calculated. Genetic distances among landraces were estimated using Nei’s coefficient and a cluster analysis using the UPGMA algorithm was performed. The results clearly indicated that: (1) Calabrian germplasm showed a high level of diversity (H e  = 0.595); (2) Mesoamerican and Andean gene pools were clearly distinguished in Calabrian germplasm, with the Andean gene pool predominating (83 %); (3) Calabrian landraces were largely hybridized within and between the gene pools. A model-based approach, using the STRUCTURE software, was adopted. Six groups, including 4 of Andean origin and one of Mesoamerican origin were identified. Even more interesting, a small group (8 %) showed a distinct genetic structure, in which interspecific hybridizations with runner bean (Phaseolus coccineus L.) could have occurred. Nevertheless, a relatively high proportion of Calabrian bean landraces (12.6 %) was derived from intra and interspecific hybridizations.  相似文献   
104.
? Studies undertaken since 1966 at research institutions in Florida illustrate the continuity of academic investigations into the effects of compost utilization. Crops that were tested — and continue to be analyzed presently — include citrus, tomatoes, peppers, container grown ornamentals, turfgrass, and trees and shrubs.  相似文献   
105.
The influence of immature municipal solid waste-biosolids composts on emergence and mean days to emergence (MDE) of several weed species was evaluated in a pot trial under greenhouse conditions. The experiment consisted of placing a 7.5 cm deep layer of three-day-old immature compost, a mature and stable compost, an artificial medium or control sand as a mulch on ivyleaf morning glory seeds. Immature three-day-old compost decreased percentage emergence, shoot and root dry weight, and increased MDE of ivyleaf morning glory. In an experiment with eight-week-old immature compost utilizing mulching depths of 2.5, 5, 7.5, 10 cm and the untreated control on seeds of three weed species, common purslane did not emerge under any of the immature compost treatments. The MDE of ivyleaf morning glory and barnyard grass increased linearly as immature compost depths increased. Next, eight economically important weed species were sown in pots with either mature or immature (eight-week-old) compost utilizing mulching depths of 2.5 and 10 cm, in addition to an untreated control. Control pots yielded higher percentages of emergence than compost treatments for all species evaluated. Common purslane, large crabgrass, pig-weed, Florida beggarweed, and dichondra did not emerge through a 10-cm deep layer of mature compost mulch, or 2.5 or 10 cm deep layer of immature mulch. Significant compost maturity/depth interactions were observed for percent emergence on common purslane, ground cherry, large crabgrass, Florida beggarweed, and ivyleaf morning glory. A thinner layer was required to suppress germination using immature eight-week-old compost as compared to mature and stable compost. Immature (three-day or eight-week-old) compost containing acetic acid concentrations of 2474 and 1776 mg.kg?1 respectively reduced percentage emergence of several economically important weed species. These studies suggest that immature composts can be used to control weeds under conditions where spatial separation is maintained between the crop and the compost and phytotoxic fermentation products do not affect the health of the mulched plants and where odors associated with such partially stabilized products do not pose problems.  相似文献   
106.
European Journal of Plant Pathology - Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici (FOL) is one of the main diseases affecting tomato plants. Three races (races 1, 2 and 3) of the...  相似文献   
107.
The object of the study was to determine the chemical composition of Diospyros lotus L. extract and their antioxidant and antiproliferative properties. Eight compounds were isolated from D. lotus and identified as gallic acid, methylgallate, ellagic acid, kaempferol, quercetin, myricetin, myricetin 3-O-β-glucuronide, and myricetin-3-O-α-rhamnoside. D. lotus extract tested in different in vitro systems (DPPH, ABTS, FRAP, and Fe2+ chelating activity assay) showed significant antioxidant activity. The potential antiproliferative properties of D. lotus extract and isolated compounds against nine human cancer cell lines such as COR-L23, CaCo-2, C32, ACHN, A375, A549, Huh-7D12, MCF-7, and LNCaP were investigated in vitro by SRB assay. D. lotus extract demonstrated the highest inhibitory activity against COR-L23 with an IC50 value of 12.2 μg/ml. Among identified hydrolysable tannins, ellagic acid evidenced strong antiproliferative activity against both C32 and A375 cells with IC50 values of 0.8 and 4.1 μg/ml, respectively. Interesting results were observed, also, with gallic acid that showed the highest cytotoxic activity against CaCo-2 (IC50 2.6 μg/ml). Overall, the results of this study suggest that D. lotus displays a good antioxidant activity and has antiproliferative effects. Both activities are related to identified phenolic compounds.  相似文献   
108.
Plant Foods for Human Nutrition - This study aimed at evaluating and comparing the chemical profile obtained by HPLC-ESI-MSn analysis, the inhibitory activity of enzymes linked to obesity...  相似文献   
109.
The effect of four drinking water temperatures (3, 10, 17 and 24°C) on water intake, feed consumption, milk yield and composition, live weight, salt consumption, and rumination, was studied with eight tied-up dairy cows of the Swedish Red and White Breed. The cows were in their 12th to 15th week of lactation at the start of the experiment. A Latin Square design was used with four periods of three weeks each in length. The cows were fed 9 kg hay, 2 kg dried molassed beet pulp and 9 kg concentrates throughout the experiment. The study was conducted from March until June in an average daily barn temperature of 15.3°C (10.2–23.7°C).Water intake was 75.6, 76.7, 76.9 and 71.5 1/day for 3, 10, 17 and 24°C respectively. The intake of the warmest water differed significantly (P<0.01) from the others. The corresponding figures for the milk yield were 25.39, 25.93, 26.33 and 26.09 kg 4% fat-corrected milk per day, where a t-test showed a significance of P<0.05 between 3 and 10°C, P<0.001 between 3 and 17°C and P<0.01 between 3 and 24°C. Feed and salt consumption, milk composition, live weight and rumination were not affected by treatment.  相似文献   
110.

Context

Disturbances create spatial variation in environments that may influence animal foraging. Granivory by rodents can influence seed supply and thus plant establishment. However, effects of disturbance patterns on rodent seed removal in western North American conifer forests are generally unknown.

Objectives

We conducted a study in lodgepole pine (Pinus contorta var. latifolia) forests of Greater Yellowstone (Wyoming, USA) to answer: (1) How do seed removal and rodent activity vary between recently burned and adjacent unburned forests and with distance from fire perimeter? (2) Which microhabitat conditions explain variability in seed removal and rodent activity?

Methods

One or two years after wildfires, we established transects (n = 23) with four stations each: at 10 and 40 m from the fire perimeter in both burned and unburned forest. At stations, we deployed trays with lodgepole pine seeds and cameras pointed at trays for 28 days and quantified habitat structure and seed abundance.

Results

Seed removal, which averaged 85%, and diurnal rodent activity did not differ between burned and unburned forests or with distance from the fire perimeter; however, nocturnal rodent activity was lower in burned forests. Seed removal and diurnal rodent activity were not associated with any microhabitat conditions we measured. However, nocturnal rodent activity was associated with microhabitat in both burned and unburned forests.

Conclusions

High seed removal rates suggested that rodent foraging was not reduced by high-severity wildfire. If observed seed removal represents natural conditions, post-dispersal seed predation could influence post-fire recruitment of a widespread foundation tree species.
  相似文献   
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