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71.
Nuclear RFLPs were used to study the genetic relationships of 2 Portuguese coles, tronchuda cabbage and Galega kale, and 13 otherBrassica oleracea cultivars and 4 nine-chromosome wild brassicas. Cluster and principal coordinates analysis were conducted using RFLP data from 60 probe-enzyme combinations, detecting 277 polymorphic restriction fragments. The results showed that the accessions clustered in five groups: one with all theB. oleracea cultivars except kailan, and the four others isolated with kailan, wildB. oleracea, B. insularis andB. cretica, andB. montana, respectively. Kailan was separated from the other accessions ofB. oleracea cultivars and genetically close to the wildB. oleracea, that was clearly separated from the other nine-chromosome wild brassicas. In theB. oleracea cultivars 3 groupings were clearly individualized: i) including broccolis and cauliflower; ii) with a misture of kales and cabbages originally from Central-North Europe; iii) formed by Portuguese coles. These preliminary results suggest the existence of three major regions of domestication of B. oleracea in Europe: Italy, Central-North Europe and Portugal. Kailan or chinese kale seems to have evolved separately from the otherB. oleracea cultivars in Eastern Asia.  相似文献   
72.
The effect of heated quercetin (400 mg/kg of oil) or 5-caffeoylquinic acid (5-CQA) and the presence of ferric ion (2.2 mg/kg of oil) on the stability of soya oil oxidized in an oxidative stability index (OSI) instrument was investigated. After heating the phenolic at 100 degrees C or 150 degrees C, the OSI values of treated oils were not significantly (p < 0.001) different, whereas, at 200 degrees C, the values decreased significantly with addition of quercetin, but not with 5-CQA. However, the antioxidative activity of quercetin remained significantly greater than that of 5-CQA. The antioxidative potency of quercetin was reduced significantly by addition of ferric palmitate (FP), but that of 5-CQA was not. Reaction between the ortho-dihydroxy groups of the quercetin and ferric ion may reduce the number of hydroxyls available to react with free radicals. Chelating action of 5-CQA might be provided by ortho-dihydroxy grouping of the quinic acid moiety.  相似文献   
73.
As forests in neotropical regions,particularly in developing countries,are devastated,interventions to restore biodiversity and its ecological functions are nee...  相似文献   
74.
Actinobacillus pleuropneumoniae, a bacterial pathogen of swine and agent of porcine pneumonia, causes a highly infectious disease of economic importance in the pig industry. Commercial vaccines for A. pleuropneumoniae include whole-cell bacterins and second generation subunit vaccines but they only confer partial protective immunity. Our search for new vaccine candidates identified antigens that are expressed during conditions that mimic infection; the outer membrane (OM) proteome of A. pleuropneumoniae serotype 5b was examined under iron restriction. Quantitative profiling by 2D-DiGE technology revealed that iron restriction induced expression of previously described transferrin binding proteins (TbpA, TbpB) plus four lipoproteins including spermidine/putrescine binding periplasmic protein 1 precursor (PotD2). Immunoproteomic analyses with antisera from na?ve animals and from infected pigs were able to differentiate antigens within the OM proteome that were specifically recognized during A. pleuropneumoniae infection. Immunoblots of iron-restricted profiles detected PotD2, heme-binding protein A (HbpA), and capsule polysaccharide export protein (CpxD) as well as surface antigens TbpA, TbpB, and OmlA. These data identify OM proteins that demonstrate immunogenicity and upregulation under conditions mimicking infection, providing emphasis on lipoproteins as an important class of antigens to exploit for vaccine development for A. pleuropneumoniae.  相似文献   
75.
Tropical Animal Health and Production - This study evaluated the effect of two doses of prostaglandin at different intervals on reproductive parameters of crossbred ewes. In Experiment 1, 30 ewes...  相似文献   
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The Prymnesiophycea Pavlova lutheriwas produced using a traditional technique (batch mode in carboys) and by an innovative technique (semi-continuous mode in alveolarphotobioreactor). Two experimental feedingtrials were carried out with Pacific oyster(Crassostrea gigas) larvae with freshand preserved (4 °C and 1 °C)P. lutheri concentrates used inmonospecific and bispecific diets, incombination with fresh Chaetoceroscalcitrans forma pumilum. Nodifferences in terms of gross composition andlarval performance were noticed between thefresh algae biomass produced by the twotechniques. The low temperatures allowedpreservation of the nutritionalcharacteristics of the P. lutheri freshculture for the time period considered (27days). The P. lutheri concentratespreserved at 4 °C or 1 °C didnot differ substantially in terms ofnutritional value. Larvae fed a monospecificdiet of P. lutheri, both fresh andpreserved, exhibited a modest growth rate (<2.1 µm day–1), in some cases notsignificantly different from that observed inthe unfed larvae (the control), and a lowsurvival rate. In contrast, when Chaetoceros calcitrans forma pumilumwas used as a monospecific diet, good growthperformance (>4.5 µm day–1) and ahigh survival rate (>86%) were observed inlarvae. A substitution of 50% (trial 1) or80% (trial 2) of fresh C. calcitransforma pumilum with the preserved P. lutheri concentrates did not adverselyaffect growth rate or survival of C.gigas larvae.  相似文献   
79.
The purpose of this study was to evaluate the physico-chemical characteristics and the post-harvest loss of mass of curly lettuce (Lactuca sativa L.) cv. Verônica that was grown in a protective environment with applications of biopesticides. The curly lettuce was treated by spraying with neem oil, cassava flour wastewater (manipueira), biofertiliser or the control treatment of deltamethrin. We determined the weight, circumference, dry matter, ash, crude protein, total phenols and minerals profile for the heads of lettuce. After harvesting, the lettuce was packed into opened plastic bags and kept at 5 °C for 5 days to evaluate its weight loss. No differences were observed among the treatments for the physico-chemical parameters. The lettuce that was sprayed with manipueira or biofertiliser had the greatest weight loss during storage. The achievement of similar yields with cheaper products suggests a benefit of using organic bioinsecticides.  相似文献   
80.
The current increase in the organic agriculture segment has created a new market for fertilisers permitted for use in organic farming. Off-farm N sources for organic farming are scarce, considering the restriction on the use of chemical fertilisers. Thus, when some products are permitted in organic agriculture, commercial opportunities become available. In this study we compare the performances of Vegethumus (Veg) and Phenix (Phe), two manures that are permitted in organic farming, with several other manures, ammonium nitrate (AN) and control treatments. A 3-year field trial and a pot experiment were carried out in order to estimate dry matter yield, N uptake, and N nutritional status of the crops, as well as soil N availability, the latter was assessed by using anion exchange membranes inserted into the soil. Apparent N recovery (ANR) values in the field trial were 6.3% and 58.2% in Veg and AN plots, respectively, after the application of 380 kg N/ha in the previous five growing seasons. In the pot experiment, the ANR of Veg and Phe, the organic amendments permitted in organic farming, were 5.0% and 13.6%, while Beiraadubo (Bei) and Nutrisoil (Nut) had ANR of 27.2% and 42.0%. The poor results of the amendments permitted in organic farming, in light of their high prices suggest that their use must be carefully considered by farmer in their fertilization strategies.  相似文献   
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