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41.
Alfredo Manicardi Laura Scarabel Josep María Llenes José María Montull María Dolores Osuna Joel Torra Farré Andrea Milani 《Pest management science》2023,79(12):4886-4896
BACKGROUND
Amaranthus palmeri is an aggressive annual weed native to the United States, which has become invasive in some European countries. Populations resistant to acetolactate synthase (ALS) inhibitors have been recorded in Spain and Italy, but the evolutionary origin of the resistance traits remains unknown. Bioassays were conducted to identify cross-resistance to ALS inhibitors and a haplotype-based genetic approach was used to elucidate the origin and distribution of resistance in both countries.RESULTS
Amaranthus palmeri populations were resistant to thifensulfuron-methyl and imazamox, and the 574-Leu mutant ALS allele was found to be the main cause of resistance among them. In two Spanish populations, 376-Glu and 197-Thr mutant ALS alleles were also found. The haplotype analyses revealed the presence of two and four distinct 574-Leu mutant haplotypes in the Italian and Spanish populations, respectively. None was common to both countries, but some mutant haplotypes were shared between geographically close populations or between populations more than 100 km apart. Wide genetic diversity was found in two very close Spanish populations.CONCLUSION
ALS-resistant A. palmeri populations were introduced to Italy and Spain from outside Europe. Populations from both countries have different evolutionary histories and originate from independent introduction events. ALS resistance then spread over short and long distances by seed dispersal. The higher number and genetic diversity among mutant haplotypes from the Spanish populations indicated recurrent invasions. The implementation of control tactics to limit seed dispersal and the establishment of A. palmeri is recommended in both countries. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献42.
43.
Miguel Mellado Lucía M. Treviño María I. Chavez Francisco G. Véliz Ulises Macías-Cruz Leonel Avendaño-Reyes José E. García 《Reproduction in domestic animals》2023,58(1):39-47
The objective of this retrospective study was to assess the effect of receiving a single (n = 50,285) or double (n = 4392) artificial insemination (AI), 12 h apart, within a timed artificial insemination protocol on pregnancy per AI (P/AI) in nulliparous heifers (inseminated with either sex-sorted or conventional semen) and pluriparous Holstein cows in a commercial dairy herd. Also, this study aimed to investigate the relationship between temperature-humidity index (THI) and time of the first AI and fertility. Fertility of cows receiving two AI with normothermia (THI <68) was higher (p < .05) than cows receiving a single AI (42.9% vs. 36.4%). P/AI of cows receiving two AI with severe heat stress (THI >85) was higher (p < .05) than cows receiving a single AI (21.0% vs. 12.6%). Regardless of heat stress conditions, applying the first AI in the morning increased (p < .05) P/AI in cows with double AI than in cows whose first AI occurred in the afternoon (38.4 vs. 33.3%). With moderate heat stress, and sexed-sorted semen, P/AI to timed AI was higher (65.0 vs. 51.9%; p < .05) in heifers receiving double AI than those serviced once. It was concluded that double AI, 12 h apart, enhanced fertility at timed AI than herd mates with a single AI, particularly with heat stress at breeding. 相似文献
44.
Anna Bassols José Angel Robles-Guirado Laura Arroyo Lourdes Soler Natalia García Raquel Pato Raquel Peña Yolanda Saco Ramon Armengol Fermín Lampreave María A. Alava Francesca Canalias Matilde Piñeiro 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2023,52(Z1):64-74
45.
46.
Santiago Bonachela Alicia María González María Dolores Fernández 《Irrigation Science》2006,25(1):53-62
Irrigation scheduling based on the daily historical crop evapotranspiration (ETh) data was theoretically and experimentally assessed for the major soil-grown greenhouse horticultural crops on the Almería coast in order to improve irrigation efficiency. Overall, the simulated seasonal ETh values for different crop cycles from 41 greenhouses were not significantly different from the corresponding values of real-time crop evapotranspiration (ETc). Additionally, for the main greenhouse crops on the Almería coast, the simulated values of the maximum cumulative soil water deficit in each of the 15 consecutive growth cycles (1988–2002) were determined using simple soil-water balances comparing daily ETh and ETc values to schedule irrigation. In most cases, no soil-water deficits affecting greenhouse crop productivity were detected, but the few cases found led us to also assess experimentally the use of ETh for irrigation scheduling of greenhouse horticultural crops. The response of five greenhouse crops to water applications scheduled with daily estimates of ETh and ETc was evaluated in a typical enarenado soil. In tomato, fruit yield did not differ statistically between irrigation treatments, but the spring green bean irrigated using the ETh data presented lower yield than that irrigated using the ETc data. In the remaining experiments, the irrigation-management method based on ETh data was modified to consider the standard deviation of the inter-annual greenhouse reference ET. No differences between irrigation treatments were found for productivity of pepper, zucchini and melon crops. 相似文献
47.
按水力学原理测得新研制的7种微管件的局部水头损失系数(C)值较同形状的大管件值大。将实测内任1~8mm微管资料计算的沿程阻力系数(λ)与雷诺数(Re).点在模迪(L·F·Moody)图中分析:平直铺放微管在Re≤2320时,相关点拟合线在层流线以上;在2320<Re<25000时,即过渡流可归并为光滑紊流计算[1]。绕曲微管水头损失虽然大于平直铺放微管,且可不分流态,进而给出可满足不同设计条件的经验公式。 相似文献
48.
Oscar Goñi María T. Sanchez-Ballesta Carmen Merodio María I. Escribano 《Postharvest Biology and Technology》2010,55(3):169-173
In order to obtain a better understanding of the active defense strategy of cherimoya (Annona cherimola Mill.) fruit, hydrolytic and antifungal activity, as well as expression of proteins functionally and immunogenically related to the pathogenesis-related proteins chitinase (PR-Q) and 1,3-β-glucanase (PR-2), were estimated in fruit at different ripening stages. Increase in expression of the 27 kDa constitutive chitinase and the induction of two new proteins, a 26 kDa chitinase and a 51 kDa 1,3-β-glucanase were associated with enhanced in vitro hydrolytic and antifungal activity of the acidic protein extract in ripe fruit. Ripening modified the expression of constitutive basic isoenzymes, with a sharp decrease in both relative accumulation and hydrolytic activity. Likewise, a new basic 33 kDa chitinase was induced in the over-ripe fruit, concomitant with accumulation of a basic constitutive 76 kDa 1,3-β-glucanase. At this stage, the basic protein extract modified in vitro growth inhibition of Botrytis cinerea. Short-term high CO2 treatment delayed fruit ripening and maintained a similar distribution of activity and isoenzymatic pattern in both protein fractions to that in unripe fruit. These results indicate that the changes in the pattern of defense proteins and hydrolytic activity in cherimoyas appear to be associated with ripening. Moreover, unlike the constitutively expressed isoenzymes, only the transitorily induced chitinases and 1,3-β-glucanases were associated with an active defense-related response. 相似文献
49.
Phytomedicines are becoming more popular all over the world. Denture stomatitis (DS) presents as an inflammatory reaction in denture-bearing patients, under maxillary prosthesis with Candida albicans being the principal etiological agent. Many different methods of treatment for DS have been observed. The effects of the main medicinal plants claimed to be useful as antifungal agents in the treatment of DS are reviewed. Herbal remedies that have shown potential promise are mentioned, although much research is still required. 相似文献
50.
María Gómez-Brandón Cristina Lazcano Marta Lores Jorge Domínguez 《Applied soil ecology》2010,44(3):237-244
The impact of detritivorous earthworms (Eisenia andrei) on microbial community structure and function in grape marc, a lignocellulosic enriched plant residue, was investigated in a mesocosm experiment. Analysis of carbon and nitrogen pools was also carried out in order to evaluate how changes in microbial communities affect plant residue decomposition. The grape marc was completely processed after fifteen days as a result of the high density of earthworms present and the rapid gut transit time. Eisenia andrei had a large impact on the structure of the microbial community, as revealed by phospholipid fatty acid analysis. Earthworm activity reduced the abundance of both bacterial (except for Gram-negative bacteria) and fungal PLFA biomarkers relative to the control values. Decreases in microbial activity and in protease and cellulase activities were also attributable to the presence of earthworms. Moreover, earthworms strongly modified the substrate utilization patterns of microbial communities, as revealed by BIOLOG analysis. The presence of earthworms led to an increase in the utilization of some amino acids and polymers, which reached a higher substrate diversity value than that in the control mesocosm. The differences in microbial communities were accompanied by a reduction in the total C content and the labile C pool, relative to the control, although there were no significant differences in either cellulose or hemicellulose contents. However, total N content increased in both mesocosms – with and without earthworms – and the concentration of NH4+ was also enhanced by earthworm activity. The results indicate that detritivorous earthworms play a key role in decomposing fresh plant residues in the short term via their intensive interactions with microbial communities. 相似文献