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排序方式: 共有138条查询结果,搜索用时 15 毫秒
131.
132.
Rakes Matheus Pasini Rafael Antonio Morais Mara Chagas Zanella Renato Prestes Osmar Damian Bernardi Daniel Grtzmacher Anderson Dionei 《Journal of pest science》2022,95(3):1121-1133
Journal of Pest Science - We evaluated the lethal and sublethal effects of azoxystrobin, cyhalofop-butyl, and thiamethoxam on Telenomus podisi after spraying rice plants in a greenhouse, as well as... 相似文献
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We studied amphibian populations in a human-dominated landscape, in Northern Italy, to evaluate the effects of patch quality and isolation on each species distribution and community structure. We used logistic and linear multiple regression to relate amphibian presence during the breeding season in 84 wetlands to wetland features and isolation. Jackknife procedure was used to evaluate predictive capability of the models. Again, we tested the response of each species to habitat features related to the richest communities. Amphibian presence depends strongly on habitat quality and isolation: the richest communities live in fish-free, sunny wetlands near to occupied wetlands. The negative effects of isolation do not seem to be biased by spatial autocorrelation of habitat features. The system shows strong nestedness: amphibian persistence depends on the contemporary effects of species adaptability and mobility. The commonest species, the pool frog (Rana synklepton esculenta) and the Italian tree frog (Hyla intermedia), are able to move through the matrix using canals and hedgerows, and can maintain metapopulations across the landscape; the rarest species (newts and toads) are more sensitive to habitat alteration, and they are strongly affected by isolation effects. If human exploitation of the landscape continues, only few species, mobile and opportunistic, will persist in this landscape. 相似文献
135.
Galletti S Bernardi R Leoni O Rollin P Palmieri S 《Journal of agricultural and food chemistry》2001,49(1):471-476
(5R)-5-Vinyl-1,3-oxazolidine-2-thione, (2S)-1-cyano-2-hydroxy-3-butene, and two diastereoisomeric erythro-(2S)- and threo-(2S)-1-cyano-2-hydroxy-3,4-epithiobutanes were prepared in pure form starting from (2S)-2-hydroxybut-3-enyl glucosinolate (epiprogoitrin). This glucosinolate was isolated in almost pure form using ripe seeds of Crambe abyssinica and then hydrolyzed under different conditions. The hydrolysis was carried out using either myrosinase immobilized on nylon, to produce (5R)-5-vinyl-1,3-oxazolidine-2-thione, or the endogenous myrosinase contained in defatted crambe meals, to produce the other epiprogoitrin-derived products. After purification and physicochemical characterization, all four myrosinase degradation products were tested for their biological activity. A bioassay on Lactuca sativa was chosen as a simple test to determine their apparent action on living tissues. (5R)-5-Vinyl-1,3-oxazolidine-2-thione negatively affected mainly root growth, whereas (2S)-1-cyano-2-hydroxy-3-butene affected the early phase of germination, and both (2S)-1-cyano-2-hydroxy-3,4-epithiobutane diastereoisomers appeared to negatively affect both germination and root growth at doses 5-10 times lower than those of (2S)-1-cyano-2-hydroxy-3-butene or (5R)-5-vinyl-1,3-oxazolidine-2-thione. 相似文献
136.
Fixed‐time post‐cervical artificial insemination in weaned sows following buserelin use combined with/without eCG 下载免费PDF全文
E Baroncello ML Bernardi AD Kummer I Wentz FP Bortolozzo 《Reproduction in domestic animals》2017,52(1):76-82
Fixed‐time post‐cervical artificial insemination (FTAI) drastically reduces labour requirements and increases the use of boars with higher genetic merit. This study evaluated the efficiency of eCG administration combined with/without the GnRH agonist buserelin for the induction and synchronization of ovulation in weaned sows submitted to FTAI. The sows were allocated into three groups. In the control group, the first artificial insemination was performed at the onset of oestrus and repeated every 24 hr. In the eCG+GnRH group, sows received 600 IU eCG at weaning and buserelin (10 μg) after 86–89 hr of eCG, and in the GnRH group, sows received only buserelin after 86–89 hr of weaning. The hormone‐treated sows received a single FTAI after 30–33 hr of buserelin application. All the sows were inseminated with homospermic doses (1.5 × 109 sperm cells/50 ml). The interval between weaning and ovulation was shorter (p < .05) in the eCG+GnRH (133.3 hr) and GnRH (135.9 hr) groups than the control (141.5 hr) group. In the eCG+GnRH group, the sows ovulated earlier (p < .05) than those in the GnRH group (44.5 vs. 48.2 hr after buserelin administration). The reproductive performance of GnRH sows was not compromised when only sows exhibiting oestrus at the time of insemination were considered, but lower farrowing rate and smaller litter size were observed in eCG+GnRH sows. The reproductive performance of eCG+GnRH sows was primarily compromised because the insemination was performed outside the optimal time relative to ovulation; therefore, it is advisable to inseminate them before 116–122 hr after weaning. 相似文献
137.
Reproductive performance of postpartum ewes treated with insulin or progesterone hormones in association with ram effect 下载免费PDF全文
JC Ferreira‐Silva SRL Basto F Tenório Filho MT Moura ML Silva Filho MAL Oliveira 《Reproduction in domestic animals》2017,52(4):610-616
The reproductive performance of postpartum Santa Inês (SI) and Morada Nova (MN) ewes treated with insulin or progesterone hormones in association with ram effect was evaluated. Ewes from SI (n = 69) and MN (n = 69) breeds were randomly allocated to three groups of each breed (T1—ram effect only; T2—ram effect + insulin; T3—ram effect + progesterone). Progesterone concentrations (ηg/ml; mean ± SD) before and after introduction of rams (n = 6) were 0.51 ± 0.22 and 3.78 ± 0.68 (T1), 0.65 ± 0.21 and 3.77 ± 0.78 (T2) and 0.52 ± 0.21 and 3.84 ± 0.84 (T3) in SI ewes and 0.74 ± 0.19 and 3.71 ± 0.56 (T1), 0.70 ± 0.21 and 3.79 ± 0.75 (T2) and 0.81 ± 0.14 and 3.87 ± 0.80 (T3) in MN ewes, respectively. Thus, lower progesterone concentrations were found before the introduction of rams (p < .05). After the introduction of rams, preovulatory peaks of LH (ηg/ml) occurred at 28 (T1), 44 (T2) and 48 (T3) hr in SI ewes and at 64 (T1), 40 (T2) and 44 (T3) hr in MN ewes. The mean number of ovulations was similar between groups (p > .05), was 1.3 ± 0.51 (T1), 1.5 ± 0.54 (T2) and 1.6 ± 0.51 (T3) in SI ewes and 1.3 ± 0.51 (T1), 1.6 ± 0.51 (T2) and 1.6 ± 0.51 (T3) in MN ewes. In conclusion, the ram effect alone is effective at inducing and synchronizing oestrus in sheep under postpartum anoestrus, irrespective of hormone treatments. 相似文献
138.
Flaviane Malaquias Costa Natália Carolina de Almeida Silva Juliana Bernardi Ogliari 《Genetic Resources and Crop Evolution》2017,64(4):681-700
‘Microcenters of diversity’ are restricted geographical areas within which a significant diversity of genetic resources is accumulated. Maize genetic variability, one of the largest among cultivated species, particularly in far western Santa Catarina, southern Brazil, has shown a rich store of landraces, conserved on farm by small-scale farmers. Thus, this study aimed to characterize the diversity of Zea mays L. landraces in two municipalities of this micro-region in Santa Catarina, as well as its geographic distribution, developing the census of diversity as a methodological proposal. Diagnosis was made according to the farmers’ knowledge. The field survey was conducted in 70 rural communities involving 2049 farms. The methodology allowed identifying 136 populations of wild relatives, of which some belong to the species Zea luxurians (Durieu and Ascherson) Bird, and 1513 populations of maize landraces, comprising 1078 of popcorn, 337 of common maize, 61 of sweet maize and 37 of flour maize. The identification of 59 morphological groups, the high use, adaptive and agronomic values, and the Shannon index (H′), estimated according to the grain shape (0.79), endosperm type (0.73), size (0.87), color (1.40), and morphological group (3.16), showed at set a considerable diversity distribution conserved on farm in this micro-region. Landrace richness and the presence of wild relative species, associated with the local human activity and sociocultural aspects, allowed to characterize the far western Santa Catarina as a ‘microcenter of diversity’ of Zea mays L. 相似文献