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51.
In Israel four European pear cultivars are grown: ‘Spadona’ is the main cultivar and ‘Coscia’, ‘Gentile’ and ‘Spadochina’ are its pollinators. However, molecular S-genotyping revealed that ‘Spadona’ is semi-compatible with its three pollinators. This explains, at least in part, the relatively low pear yield in Israel. The Syrian pear (Pyrus syriaca) grows wild in Israel and blooms intensively, overlapping the blooming of the cultivated European pears. Cross-fertilization between Syrian pear and ‘Spadona’ was shown to be efficient suggesting that Syrian pear might be a potent pollinator for ‘Spadona’. Twenty-six Syrian pear seedlings, from different sites in north-east Israel were S-genotyped identifying 11 that are fully compatible with the four European pear varieties cultivated in Israel. By this screening, 24 different S-RNases were cloned; ten of them are new, whereas the other fourteen had been identified previously. In addition, seedlings of two wild pear species were also S-genotyped. Two seedlings from Pyrus betulifolia and one from Pyrus korshinskii were found to be genetically compatible with the four European pear cultivars. From these seedlings four S-RNases were cloned, two are new, one had been cloned previously and one was identical to an S-RNase allele cloned from Syrian pear in this work.  相似文献   
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Susceptibility to acephate, methomyl, and permethrin was determined with laboratory bioassays for adults of greenhouse whitefly, Trialeurodes vaporariorum Westwood, from 12 to 14 sites in Hawaii. Comparisons at LC50 showed up to 42-fold resistance to acephate, 36-fold resistance to methomyl, and 8-fold resistance to permethrin. Higher levels of resistance to acephate and methomyl than to permethrin are consistent with greater use of organophosphates and carbamates than pyrethroids by growers. Insecticide use varied from 1 to 98 insecticide sprays per site per season. Significant positive associations between LC50 for each insecticide and frequency of application of the same insecticide were found across sites. This finding suggests that local variation in insecticide use was an important cause of variation in susceptibility.  相似文献   
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Microorganisms play a major role in the degradation and detoxification of most soilapplied pesticides. Any interference with soil microbial activity may affect the persistence as well as the effectiveness of the pesticide. The objective of this study was to investigate the effect of granulated superphosphate fertilizers on terbutryn (2-(tert-butylamino)-4-(ethylamino)-6-(methylthio)-l,3,5-triazine) degradation and on its herbicidal activity. Concentrations exceeding 1% of superphosphate in the soil slowed down terbutryn degradation; a concentration of 3% completely inhibited terbutryn degradation for nearly 60 days. When terbutryn was impregnated on the surface of superphosphate granules, the concentration of the fertilizer that inhibited terbutryn degradation was reduced from 3% to 0.1%. Bioassays with mustard seedlings confirmed the results obtained by chemical analysis of terbutryn. The decrease in the rate of terbutryn degradation was not specific to superphosphate. The inhibition of degradation could be attributed mainly to the concentration of the salt in the soil solution, expressed as electrical conductivity values, and not to the pH of the soil or to the type of the salt. Terbutryn was found to be quite stable on the surface of the superphosphate granule. At the concentrations tested, superphosphate did not affect root growth. The optimal weight of the impregnated granule for extending terbutryn activity was 125 mg, containing 0.2% terbutryn. A greenhouse experiment confirmed the findings that fertilizers could serve as potential inhibitors of terbutryn degradation.  相似文献   
56.
This study investigated the effects of low potassium diets with different levels of Ca compared to two diets low in dietary cation–anion difference (DCAD) fed prepartum as a strategy to prevent hypocalcemia on sorting behaviour, total tract digestibility, oxidative status and energy and protein metabolism of transition cows. Forty-eight pregnant dairy cows were assigned to 4 treatment groups: Low Ca, low K (LCLK), High Ca, low K (HCLK), Supplementation with anionic mineral mixture (AMS) supplementation with SoyChlor (CAS). After parturition, all animals were fed a standard postpartum diet. Data were collected until 21 DIM. Prepartum urinary pH was significantly reduced by the low DCAD diets, while postpartum Ca homeostasis was affected by the HCLK ration. Feeding AMS induced sorting against particles <1.18 mm in favour of particles >19 mm prepartum. In contrast, cows fed CAS showed an increase in selective consumption of fine particles and sorted against longer particles similar to the HCLK and LCLK groups. Postpartum sorting activity was not affected by the dietary treatments. After calving, apparent digestibility of NDF was significantly reduced in the HCLK group. Prepartum, we observed effects on serum concentrations of non-esterified fatty acids were higher and insulin sensitivity was lower in the AMS group. Blood urea nitrogen (BUN) was decreased in cows fed the CAS ration. Postpartum, we found serum protein to be decreased with the low DCAD diets while BUN was decreased in the CAS group. The low DCAD rations increased prepartum serum malondialdehyde concentrations, while postpartum total antioxidant capacity was lower in the HCLK and the AMS group. From these data, we conclude that AMS decreased prepartum intake due to compromised palatability. Intermediate protein metabolism was affected by the low DCAD diets, while parameters of oxidative stress were probably affected by acid–base balance and Ca homeostasis.  相似文献   
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Tropical Animal Health and Production - Contagious caprine pleuropneumonia (CCPP) is one of the most fatal and contagious diseases of goats. To date, the occurrence of CCPP in Egypt has not been...  相似文献   
58.
To find out more about the biochemical aspects of seed-softness trait in pomegranate (Punica granatum L.), some of the phenylpropanoid pathway enzymes as well as their products were evaluated in the various soft- and hard-seeded genotypes during fruit development. Results showed that peroxidase (POD) activity decreased in all studied genotypes during fruit growth, while increasing at the last stages only in the hard-seeded genotypes. Although laccase (LAC) activity did not show high differences during fruit ripening and in different genotypes, but its general trend was increasing. Phenylalanine ammonia-lyase (PAL) activity decreased during the fruit development and approximately diminished for the hard-seeded genotypes. All genotypes had lignin components in their seeds and amount of lignin increased during the growth season. Total phenolic decreased drastically and antioxidant capacity increased gradually showing an opposite trend and probable competitive effect for the same substrate during fruit development. Considerable differences that were observed in the POD activity at the last sampling stage, and higher activity that was observed in POD than LAC, may indicate that POD is more important for polymerization of lignin in the pomegranate seed and this enzyme might have some role in the development of seed softness trait in pomegranate. Also, this is the first report about lignin detection in the seeds of soft-seeded pomegranate genotypes, and represents a different mechanism (such as monolignol conformation in the final polymer) from lignin content for development of the soft-seeded pomegranate genotype.  相似文献   
59.
Final observations on experimental transmission of chronic wasting disease (CWD) from elk (Cervus elaphus nelsoni) and white-tailed deer (Odocoileus virginianus) to fallow deer (Dama dama) are reported herein. During the 5-year study, 13 fawns were inoculated intracerebrally with CWD-infected brain material from white-tailed deer (n = 7; Group A) or elk (n = 6; Group B), and 3 other fawns were kept as uninoculated controls (Group C). As described previously, 3 CWD-inoculated deer were euthanized at 7.6 mo post-inoculation (MPI). None revealed presence of abnormal prion protein (PrP(d)) in their tissues. At 24 (Group A) and 26 (Group B) MPI, 2 deer were necropsied. Both animals had a small focal accumulation of PrP(d) in their midbrains. Between 29 and 37 MPI, 3 other deer (all from Group A) were euthanized. The 5 remaining deer became sick and were euthanized between 51 and 60 MPI (1 from Group A and 4 from Group B). Microscopic lesions of spongiform encephalopathy (SE) were observed in only these 5 animals; however, PrP(d) was detected in tissues of the central nervous system by immunohistochemistry, Western blot, and by commercial rapid test in all animals that survived beyond 24 MPI. This study demonstrates that intracerebrally inoculated fallow deer not only amplify CWD prions, but also develop lesions of spongiform encephalopathy.  相似文献   
60.
In the present study 13 Arcanobacterium pluranimalium strains isolated from various animal origin could successfully be identified phenotypically by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and genotypically by sequencing 16S rDNA and the pluranimaliumlysin encoding gene pla. The detection of mass spectra by MALDI-TOF MS and the novel genotypic approach using gene pla might help to identify A. pluranimalium in future and might elucidate the role this species plays in infections of animals.  相似文献   
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