不同栽植密度对脱毒红薯产量及经济效益的影响

为确定三康8号脱毒红薯的最佳栽植密度并为其推广应用提供依据,采用大田试验方法,研究了不同栽植密度对脱毒红薯产量和经济效益的影响。结果表明:栽植密度为4 600株/667m2时,鲜薯产量高达2 577.9 kg/667m2,产投比高达2.37,是三康8号脱毒红薯的最佳栽植密度。     

冬季凌汛危害成因及防凌管理措施

通过分析冬季凌汛危害的成因,总结出防止凌汛的管理措施,对保证凌汛安全将起到很大的作用。     

Differences in ecological and allelopathic traits among Alternanthera philoxeroides populations

Based on a field investigation and laboratory trials, this study compared the invasive ecology of aquatic and terrestrial alligator weed (Alternanthera philoxeroides G.) ecotypes. The aquatic ecotype showed a stronger eco‐adaptation than the terrestrial ecotype. Alligator weed performed well in wetland and riparian habitats, where it was so competitive that only one‐to‐three other plant types grew successfully in its company. In contrast, it exhibited poor growth in upland fields and parks, where the terrestrial ecotype was dominated by 6–11 other alien plant species. The aquatic ecotype exhibited significantly greater growth inhibition of Microcystis aeruginosa. The ecotypes differed in their pattern of allelopathic inhibition of water blooms. The allelopathic effect of the aquatic ecotype persisted for a period exceeding 20 days, whereas the terrestrial ecotype's allelopathic effect subsided in <5 days. The aquatic ecotype had higher levels of antioxidant compounds, including soluble protein and flavones, and the activity of protective enzymes was also higher, which included superoxidase dismutase, peroxidase and catalase. Alligator weed's unique characteristics derive mainly from its strong allelopathic potential and tolerance of eutrophication in aquatic habitats.     

辽宁动漫游戏产业发展问题及对策研究

动漫产业被誉为21世纪最具发展潜力的朝阳产业之一。近年来,辽宁动漫产业发展迅猛,取得了巨大的成就。但对辽宁动漫产业发展现状进行分析后发现仍存在诸多问题。在世界经济格局重新调整的契机下,实施有效的发展战略是辽宁动漫游戏产业发展的根本保证。     

猕猴桃的后期管理

加强猕猴桃的后期管理 ,是提高果实品质 ,保证正常成熟的重要环节。1　改善光照条件8月中旬高温期过后 ,对二次副梢或三次副梢进行缩剪 ,若春梢摘心留叶数为 8片或 1 0片叶时 ,二次枝应在 3片至 5片叶处短截 ;有三次副梢出现的旺枝 ,将三次枝留 2片至 3片叶重剪或直接疏去。若春梢在 4片叶至 6片叶处缩剪 ,二次枝亦应在 4片至 6片叶处缩剪 ,将三次或四次副梢疏去。树势较旺者 ,对内膛细弱枝或自封顶枝 ,应适当中截着果节以上的枝段。行与行之间留足 80～ 1 0 0ｃｍ的间距 ,避免行间枝梢交叉。秋剪的主要对象是二次或三次 (四次 )副梢及其他…     

加强基层野生动物行政管理工作的探讨

概括总结基层野生动物行政管理的重要性,并就如何加强基层野生动物行政管理提出了五个方面的意见。     

Sequencing, Polymorphism and Expression Profile Analysis of Porcine Hexokinase Ⅱ (HK2) Gene

Hexokinase Ⅱ has been demonstrated to play the role of a key enzyme member in the glycolysis reaction. It catalyzes the conversion of glucose to glucose-6-phosphate, thus committing glucose to the glycolytic pathway. In this paper, the partial exons and introns 10, 11, 13 and 14 of the porcine HK2 gene were cloned and sequenced by comparative genomics.Comparative sequencing of three pig breeds revealed ten putative single-nucleotide polymorphisms (SNPs), one of which in intron 10 with differing bases (G981A) is within the restriction site for enzyme Msp Ⅰ. Distribution of Msp Ⅰ -RFLP genotype and allele frequencies among different pig breeds were studied. By association analysis between Msp Ⅰ PCR-RFLP polymorphism (AA, AB, BB genotypes of HK2 gene intron 10) and some meat quality and carcass traits in F2 group,which was constructed by our laboratory, a significant difference of pig average backfat at rump was found between AB and BB genotypes (P ＜ 0 05) in F2 group. In addition, the pattern of expression of HK2 in a variety of tissues in pig was also determined using semi-quantitative RT-PCR. The expression of HK2 mRNA was detected only in pig skeletal muscle.     

普那菊苣饲喂三元杂交猪的效果

利用普那菊苣青绿叶片配合精料育肥三元杂交肉猪,经过105 d的育肥,在5个不同搭配组合中,当青料干物质占日粮干物质的25.96%时,头日均增重最快,为692.12 g;瘦肉率较高,为63.78%,与对照差异达极显著(P＜0.01);屠宰率为74.06%,饲料转化率为3.02 kg,比对照低,但成本减少61.93元,效益增加60.19元;经济效益最高,为173.36元,与其他几个组合差异极显著(P＜0.01),是一个比较理想的搭配组合,可直接用于生产推广.     

新疆野苹果叶形性状变异及其与SSR标记关联分析

以从新疆天山地区新疆野苹果600个无性系中筛选得到的18个优系为研究对象,调查其叶形性状变异,并进行了SSR分子标记分析,探究叶形性状与SSR标记间的相关关系。结果表明,调查的15个叶形性状在无性系间均存在极显著差异;平均变异系数最大的为叶尖角α(达到25.39%),叶形指数L1/L3最小(仅为10.31%);叶片长的重复力最大(达到0.967),叶形指数L1/L3最小(仅为0.495)。以15个叶片性状为依据,可将各无性系完全区分开,并分为3类,各无性系间的遗传距离变化在1.293~7.235间。用均匀分布在17个染色体连锁群上的30对多态性SSR引物对18个无性系进行聚类分析,可将各无性系完全区分开,并可分为4类,各无性系间的遗传距离为0.089~0.689,平均遗传距离为0.433。所有叶形性状聚类结果与所有SSR标记聚类结果不相关。以单一叶形性状聚类结果与经过筛选的部分SSR标记聚类结果进行相关分析,绝大部分达到极显著相关,且大部分引物组合表现为累积效应,表明叶形性状与部分SSR位点具有紧密关联。