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651.
Jaime A. Teixeira da Silva Mafatlal M. Kher Deepak Soner M. Nataraj Judit Dobránszki Melissa A. Millar 《Agroforestry Systems》2018,92(5):1301-1315
Species of the Santalum genus are well known for their fragrant hardwood, which has great value in medicinal, pharmaceutical and cosmetic industries. Sandalwood oil is derived from the heartwood of Santalum sp. and contains α-, β- and epi-β-santalols, which are responsible for its pleasant fragrance. Oil content can vary from species to species. Pressure on natural populations due to habitat loss, legal and illegal harvesting and disease is increasing. This paper highlights the development of molecular markers for the refinement of phylogenetic studies, identification of various Santalum and adulterant species, assessment of genetic diversity, genetic differentiation, clonality and management units within species, and for marker-assisted breeding. The identification of quantitative trait loci for sandal spike disease and for other traits such as specific rare secondary metabolites in the essential oil and related to its fragrance, would also benefit from molecular advances. RNA sequence analyses have already identified changes in gene expression and metabolic pathways in developing Santalum album L. haustoria. 相似文献
652.
Marco Antonio Previdelli Orrico Junior Ana Carolina Amorim Orrico Débora Maurício Manarelli Walter Renato Teixeira Lopes Alice Watte Schwingel 《Compost science & utilization》2018,26(2):91-97
The different organic matter fractions of residues significantly impact the degradability of organic material in composting windrows. Based on that, this study aimed to find out the organic matter fractions that most impact the breakdown rate during composting, besides proposing models to estimate the solids reductions in sheep bedding composting windrows. To that end, 24 sheep beddings from different locations and varied composition were composted so as to ensure the representativeness of the sample. The models found for reduction in total (TS) and volatile (VS) solids as a function of compostable organic matter (COM) and organic matter resistant to composting (OMRC) were not significant. Lignin had correlation coefficients of ?0.6, ?0.89, and ?0.84 in relation to temperature, TS reduction, and VS reduction, respectively. The hemicellulose:lignin ratio was the parameter most correlated with temperature (0.69), TS reduction (0.91), VS reduction (0.92), and nitrogen (0.5), which led to more significant predictive models. It can be concluded that the hemicellulose:lignin ratio is the parameter that most impacts the breakdown of organic matter and nitrogen losses in sheep bedding composting windrows. 相似文献
653.
【目的】对中国6个区域奶牛子宫内膜炎病原菌的种类和区域分布特征进行研究,为筛选出最佳治疗药物以减少子宫内膜炎对畜牧业造成经济损失提供数据支持。【方法】分别从赤峰区域、张家口区域、潍坊区域、重庆区域、宝鸡区域和北京区域选择不同规模的奶牛养殖场中患子宫内膜炎的奶牛,用采样器每个区域采集60份(6个区域共计360份)患病牛的子宫内容物,通过革兰氏染色和生化鉴定的方法鉴定分离纯化的奶牛子宫内膜炎病原菌,并分析病原菌的分布特征。【结果】潍坊、赤峰、北京区域引起奶牛子宫内膜炎以单一感染为主。宝鸡、张家口、重庆区域引起奶牛子宫内膜炎以混合感染为主。赤峰、重庆、张家口、潍坊、宝鸡、北京区域引起奶牛子宫内膜炎的病原菌以革兰氏阳性菌为主。赤峰奶牛子宫内膜炎的主要致病菌是葡萄球菌。重庆奶牛子宫内膜炎的主要致病菌是链球菌。张家口奶牛子宫内膜炎的主要致病菌是大肠杆菌。潍坊奶牛子宫内膜炎的主要致病菌是链球菌。宝鸡奶牛子宫内膜炎的主要致病菌是葡萄球菌。北京奶牛子宫内膜炎的主要致病菌是蜡样芽孢杆菌。 相似文献
654.
The objective of this study was to evaluate the response of common bean plants to phosphorus (P) applied to the leaves at different growth stages, as a complement to phosphate fertilization at sowing. The experiment followed the 2 × 7-factor randomized block design (RBD) with four replicates. The first factor was fertilization with P at the base with 60 and 120 kg ha?1 of phosphorus pentoxide (P2O5). The second factor was the times and doses of P applied to the leaves: 0.5 or 1 kg ha?1 of P2O5, at the V3 phenological stage; parceled in the following manner: 20% in V3, another 40% in R5 and 40% in R6, or 50% in R5 and 50% in R6; and one treatment with no P2O5 application to the leaves. P-based foliar fertilization increased P content in the grains of plants grown in soils with greater P availability. The lower common bean biomass production under scarce P availability was minimized by the foliar fertilization, as well as its productivity when 1 kg ha?1 of P2O5 was applied to the leaves, 50% in the R5 phenological stage and 50% in R6. The highest productivity was obtained with the application of 0.5 kg ha?1 of P2O5 to the leaves in the V3 phenological stage with the 120 kg ha?1 dose at the base. 相似文献
655.
Lethal and sublethal effects of chlorantraniliprole on three species of Rhagoletis fruit flies (Diptera: Tephritidae) 总被引:1,自引:0,他引:1
BACKGROUND: Chlorantraniliprole formulated as a 350 g kg?1 WG (Altacor 35WG) for management of apple maggot Rhagoletis pomonella (Walsh), blueberry maggot R. mendax Curran and cherry fruit fly R. cingulata (Loew) (Diptera: Tephritidae) was evaluated in laboratory assays and field trials. RESULTS: A tarsal contact toxicity bioassay showed that a surface residue of 500 mg L?1 of chlorantraniliprole caused significantly higher mortality of male and female flies of all species compared with a control. Male apple maggot and blueberry maggot mortality was significantly higher than that for females, but there was similar mortality of male and female cherry fruit flies. An ingestion toxicity bioassay showed that 500 mg L?1 of chlorantraniliprole in diet caused significantly higher mortality of male and female flies of all species than the control, but there were no significant differences among the sexes. Delayed egglaying by females that had ingested chlorantraniliprole was found, but there were no significant sublethal effects on either the number of eggs laid or the egg hatch. Field trials with apple maggot and cherry fruit fly showed that protection of fruit by chlorantraniliprole was comparable with that of standard broad‐spectrum insecticides. CONCLUSIONS: The present data indicate that chlorantraniliprole has suppressant activity against Rhagoletis fruit flies, preventing fruit infestation primarily through direct lethal effects. Copyright © 2008 Society of Chemical Industry 相似文献
656.
Hector M Menendez III Jameson R Brennan Charlotte Gaillard Krista Ehlert Jaelyn Quintana Suresh Neethirajan Aline Remus Marc Jacobs Izabelle A M A Teixeira Benjamin L Turner Luis O Tedeschi 《Journal of animal science》2022,100(6)
Modern animal scientists, industry, and managers have never faced a more complex world. Precision livestock technologies have altered management in confined operations to meet production, environmental, and consumer goals. Applications of precision technologies have been limited in extensive systems such as rangelands due to lack of infrastructure, electrical power, communication, and durability. However, advancements in technology have helped to overcome many of these challenges. Investment in precision technologies is growing within the livestock sector, requiring the need to assess opportunities and challenges associated with implementation to enhance livestock production systems. In this review, precision livestock farming and digital livestock farming are explained in the context of a logical and iterative five-step process to successfully integrate precision livestock measurement and management tools, emphasizing the need for precision system models (PSMs). This five-step process acts as a guide to realize anticipated benefits from precision technologies and avoid unintended consequences. Consequently, the synthesis of precision livestock and modeling examples and key case studies help highlight past challenges and current opportunities within confined and extensive systems. Successfully developing PSM requires appropriate model(s) selection that aligns with desired management goals and precision technology capabilities. Therefore, it is imperative to consider the entire system to ensure that precision technology integration achieves desired goals while remaining economically and managerially sustainable. Achieving long-term success using precision technology requires the next generation of animal scientists to obtain additional skills to keep up with the rapid pace of technology innovation. Building workforce capacity and synergistic relationships between research, industry, and managers will be critical. As the process of precision technology adoption continues in more challenging and harsh, extensive systems, it is likely that confined operations will benefit from required advances in precision technology and PSMs, ultimately strengthening the benefits from precision technology to achieve short- and long-term goals. 相似文献
657.
Luara Castilho Pereira Leonardo Balbinot Gregorio Nolazco Matus Herly Carlos Teixeira Dias Kelly Cristina Tonello 《林业研究》2021,42(6):2301-2311
Although the scientific knowledge about some associations between physical parameters of the soil is con-solidated,studies focused on investigating the dynamics... 相似文献