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为了弄清成熟蓝果忍冬结合力的特性和变化规律、给机械化收获提供技术依据,在蓝果忍冬成熟期间对4个常见品种果实结合力进行了为期16天的跟踪测试。通过分析研究得出:所测试的4个蓝果忍冬品种的结合力分布在0.1~1.7 N之间(P0.05),各品种结合力分布区间略有不同,所测试的野生阿尔泰忍冬、蓓蕾的结合力高于蓝鸟和长白山野生蓝靛果忍冬;各品种结合力随时间呈现出不同程度的下降趋势;同一天内下午的结合力显著大于上午的结合力(P0.05);晴天与阴雨天的结合力无显著性差异。通过因子分析,可将影响结合力的因素测试时间、上下午、相对湿度、温度及天气状况转换成环境因子和时间因子。 相似文献
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Molecular cloning and sequence analysis of an LFY homologous gene from Juglans regia L. 总被引:1,自引:0,他引:1
The existence of a long juvenile phase is found seriously to affect the early-stage economic benefits of later mature walnuts
(Juglans regia L.). Studies on LFY, a key gene controlling floral transition and flower differentiation, may be helpful in solving the problem. This study reports
the identification and characterization of a JrLFY gene from Juglans regia L., a homolog of FLORICAULA/LFY. The gene was isolated from flower buds of precocious walnut cultivar Zhonglin No. 5 by RT-PCR and RACE. The cDNA sequence
of JrLFY (GenBank accession no. GU194836) was 1496 bp and contained an ORF of 1158 bp. Its corresponding genomic sequence (GenBank
accession no. HQ019159) showed that the JrLFY contained three exons and two introns. The predicted amino acid sequence of the gene consisted of 385 amino acids and had
a conserved region in the C-terminal when being aligned with sequences of other LFY homologs. Phylogenetic analysis showed
that the LFY protein of walnut was close to those of hickory and chestnut. These studies will lay a foundation for understanding
the mechanism of early fruiting and preparation for transfer of the JrLFY as a transgene to later mature walnuts. 相似文献
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不同施肥措施对灰枣园土壤速效养分含量的影响 总被引:2,自引:0,他引:2
为了探讨灰枣生长期内不同施肥处理措施对枣园土壤速效养分含量的影响情况,于2014年3月采用不施肥、常规施肥和施用不同种类生物肥共3大类9种处理进行田间试验,并于同年7~10月在灰枣不同生长期测定了各处理区域土壤中的碱解氮、速效磷、速效钾、有机质这4种养分的含量,研究了不同施肥处理下灰枣不同成熟期土壤各养分的动态变化情况。结果表明,不同处理、不同成熟期土壤各养分含量间均有差异,施用生物肥可以显著提高土壤中各养分的含量。 相似文献
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铲头堆砂白蚁Cryptotermes declivis Tsai et Chen是破坏木材及木制品的重要干木白蚁,其有翅成虫通过分飞配对后建立新群体,是其重要繁殖扩散途径。本文对铲头堆砂白蚁原始繁殖蚁形成周期进行了研究。以似桂木Paratocarpus sp.、团花Anthocephalus chinensis(Lam.) Rich. et Walp.和球花豆Parkia sp.作为该种白蚁食料,研究其原始繁殖蚁配对后从新建群体的形成到产生下一代的原始繁殖蚁,完成1个世代生活周期。结果表明,铲头堆砂白蚁在室温下,新建群体的形成、发展、发育至下一代原始繁殖蚁形成的周期约5 a,不同寄主材料对铲头堆砂白蚁生活周期没有显著性影响,但与群体数量多少显著相关。本研究首次明确了铲头堆砂白蚁群体发育成熟的周期,对该害虫的检疫与防控研究具有重要参考价值。 相似文献
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试验旨在分析绵羊初乳和常乳乳蛋白质组的差异,揭示绵羊不同泌乳阶段的乳蛋白质组特征。选用6只胎次相同、预产期相近的湖羊母羊,分别采集分娩后第1、3、7天的初乳和第14、28、56天的常乳,每个时间点采集6份奶样并等体积混合,离心弃去乳脂肪,采用双向电泳(2-DE)技术对初乳和常乳的脱脂乳蛋白进行比较分析。结果发现,初乳中乳蛋白含量较高,且随着泌乳期的延伸,乳蛋白含量降低。以第1天乳蛋白2-DE图谱为参照,第3天检测到38个差异蛋白点,其中有20个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第3天图谱中,其余17个蛋白点呈现表达量的差异;第7天检测到35个差异蛋白点,其中有19个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第7天图谱中,其余15个蛋白点呈现表达量的差异;第14天检测到34个差异蛋白点,其中有11个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第14天图谱中,其余22个蛋白点呈现表达量的差异;第28天检测到38个差异蛋白点,其中有28个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第28天图谱中,其余9个蛋白点呈现表达量的差异;第56天检测到36个差异蛋白点,其中有26个蛋白点仅存在于第1天图谱中,有1个蛋白点仅存在于第56天图谱中,其余9个蛋白点呈现表达量的差异。综上,共检测出44个差异表达的蛋白点,其中有8个蛋白点仅存在于第1天图谱中,而这些蛋白主要涉及免疫活性功能。 相似文献
10.
Scott A Kramer Brooklyn K Wagner Ivelisse Robles Steve J Moeller Andrew S Bowman Justin D Kieffer Andria Gonalves Arruda Michael D Cressman Monique D Pairis-Garcia 《Journal of animal science》2021,99(3)
Euthanasia of mature swine is challenging. Temporal and behind-the-ear locations are two sites that have been identified as alternatives to the more commonly used frontal placement. In stage one, the effectiveness of two penetrating captive bolt gun styles (cylinder or pistol) was evaluated using frontal, temporal, and behind-the-ear placement in anesthetized mature swine (n = 36; weight: 267 ± 41 kg). For stage one, when evaluating treatment efficacy by sex, the cylinder-style equipment was 100% effective in achieving death when applied to all cranial locations (frontal, temporal, and behind-the-ear) for sows; however, the pistol-style equipment was only 100% effective when applied at the behind-the-ear location for sows. For boars, the cylinder-style equipment was 100% effective when applied to the frontal and behind-the-ear location, but the pistol-style equipment was not effective for any cranial location in boars. Therefore, the pistol–frontal, pistol–temporal, pistol–behind-the-ear, and cylinder–temporal were not included for boars, and pistol–frontal and pistol–temporal were not included for sows in stage two. In stage two, commercial, mixed-breed, mature swine (n = 42; weight: 292 +/− 56 kg) were randomly assigned to one of four treatments based on the inclusion criteria described in stage one. A three-point traumatic brain injury (TBI) score (0 = normal; 1 = some abnormalities; 2 = grossly abnormal, unrecognizable) was used to evaluate six neuroanatomical structures (cerebral cortex, cerebellum, hypothalamus, thalamus, pons, and brain stem), and the presence of hemorrhage was also noted. All treatments were 100% effective in stage two. A significant interaction between gun style and placement was determined on predicting total TBI as the cylinder style produced a higher total TBI score compared with the pistol type of the magnitude of +2.8 (P < 0.01). The cylinder style tended to produce a greater TBI score than the pistol in the temporal location (+1.2; P = 0.08). No difference was noted for TBI score behind-the-ear between the cylinder- and pistol-style gun (P > 0.05). TBI tended to be less in boars compared with sows (−0.6; P = 0.08). Hemorrhage was observed in frontal, parietal, occipital, and temporal lobes. This study demonstrated that the cylinder-style captive bolt gun more effectively resulted in brain trauma and death compared with a pistol-style gun and the behind-the-ear and temporal placement showed promise as an alternative placement site for euthanizing mature pigs on-farm. 相似文献