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51.
两种吡虫啉种衣剂在棉花和土壤中的残留动态研究 总被引:7,自引:1,他引:7
采用田间试验方法,研究了两种吡虫啉种衣剂在棉花和土壤中的残留消解动态,并对其在棉花上使用的安全性作出了评价。结果表明,两种吡虫啉种衣剂无论在棉株中或土壤中消解动态没有显著差异,其消解速度相当缓慢,有较长的药效。试验还表明,无论是推荐药量还是加倍药量.在正常使用条件下,都不会造成棉子残毒污染和土壤的残留积累。 相似文献
52.
为了探索辅酶Q10污泥施用对土壤和作物的影响,以玉米为供试作物,进行了不同用量污泥施用及与单施化肥对比的田间试验。结果表明,污泥施用增加了玉米的株高,400kg/667m2施肥量比空白区平均增加14cm,比单施化肥区平均增加6.5cm;400kg/667m2施肥量比空白区增产10%~15%,达到差异显著水平,与单施化肥区无显著差异;施用污泥与空白区相比,玉米籽粒蛋白质、脂肪和淀粉含量均有所提高,与单施化肥相比,污泥对提高籽粒蛋白质含量的作用更明显;污泥施用后对提高土壤中磷的作用最大,其次为氮,对有机质和钾的影响微乎其微,对土壤的p H值没有影响。辅酶Q10污泥施用对玉米生长、产量形成和品质均具有良好的效应,同时能够起到培肥土壤的作用。 相似文献
53.
基于改进生态足迹模型的西北地区生态可持续性评价 总被引:2,自引:0,他引:2
西北地区的生态可持续状况对于稳定生态环境,改善人地关系具有重要的现实意义。传统生态足迹模型(EFM)中存在诸多不足和缺陷,文中对原有模型进行了改进并对西北地区2012年生态可持续性进行了计算和评价。结果表明:1)西北地区人均生态足迹为2.90hm2/人,人均生态承载力为2.18hm2/人,人均生态赤字为0.72hm2/人,整体的生态结构不合理,处于不可持续状态;2)西北地区各省区的生态足迹差异明显,除青海和新疆为生态盈余外,其它省区均为生态赤字,其中陕西最大,甘肃最小;3)西北地区生态适度人口为0.74×108人,实际人口与生态适度人口的比例是1:0.75,人口数量整体处于超载状态;生态利用效率为0.65万元/hm2。改进生态足迹模型能够较好地评价生态可持续现状,研究方法和结果对于区域生态可持续发展研究具有一定的参考价值。 相似文献
54.
为解决平菇栽培原料供应价格飙升、供应紧张的现状,以平菇为试材,在平菇栽培培养料中按不同比例添加葡萄枝屑(0、30%、50%、70%),研究葡萄枝屑对平菇菌丝体生长、子实体产量及子实体营养成分的影响。先将葡萄枝屑、玉米芯、土霉素药渣等原料按不同比例浸泡混匀,装袋培养灰色平菇栽培种,采用柱前衍生反相高效液相色谱法测定平菇子实体氨基酸含量,按照国家标准测定方法测定平菇中微量元素含量。结果表明:添加适宜比例葡萄枝屑栽培平菇,菌丝体长势强,生长速率高,菌丝洁白、粗壮、紧密;添加葡萄枝屑可显著提高平菇产量,其中以添加50%葡萄枝屑的平菇产量最高(324.0 g/袋),且加入葡萄枝屑3个处理的生物学效率为90.3%~99.7%;添加葡萄枝屑可提高平菇子实体中铁、锌、硼等微量元素的含量;4个基质配方栽培的平菇基本能满足人体对必需氨基酸的搭配需求,且添加葡萄枝屑栽培的平菇赖氨酸含量显著高于不添加葡萄枝屑的对照。因此,加入葡萄枝屑可提高平菇的产量及微量元素含量,满足人体对必需氨基酸的需求。 相似文献
55.
Genetic screening of FecB,FecXG and FecXI mutations and their linkage with litter size in Barki and Rahmani sheep breeds 下载免费PDF全文
AS El‐Seedy NM Hashem KM El‐Azrak ANM Nour El‐Din TA Ramadan TA Taha MH Salem 《Reproduction in domestic animals》2017,52(6):1133-1137
Characterization of fecundity genes offers the opportunity to improve production efficiency, and the consequent increase in litter size in livestock industry, through utilizing them in breeding programs. The main objective of this study was to detect the BMPR‐IB, BMP15 and GDF9 gene mutations and to investigate whether these mutations are associated with litter size in Egyptian sheep breeds. To achieve this goal, 73 adult ewes representing Barki (n = 33) and Rahmani (n = 40) breeds were used. Polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) screening approach was used to detect the presence of FecB, FecXG and FecXI mutations in the two selected breeds. Results of this study showed that the three different candidate gene mutations, namely FecB, FecXG and FecXI are not present among these selected populations of the Egyptian breeds. Further studies regarding other mutations and/or other genes, which may influence ovulation rate, should be carried out to determine the type and mode of inheritance of such genes in Egyptian sheep breeds. 相似文献
56.
Summary Stereological procedures were used to estimate the amount of amyloid deposition in the pancreatic islets of 83 cats from random sources in south-eastern Queensland. Most had only minor deposits of less than 20% of islet volume (median 9%), but deposits equal to more than 50% of the islet volume were found in 10% of the cats. Amyloid deposition in pancreatic islets was correlated with the age of the cat. Although similar observations have been made previously in cats from the USA, the frequency of amyloid deposition was higher in this population of cats from south-eastern Queensland. 相似文献
57.
Siddall TL Ouse DG Benko ZL Garvin GM Jackson JL McQuiston JM Ricks MJ Thibault TD Turner JA Vanheertum JC Weimer MR 《Pest management science》2002,58(12):1175-1186
A novel series of substituted 3-phenyl benzoylpyrazoles were prepared and tested as potential grass herbicides. The targeted materials were prepared by three newly developed synthetic routes, which allowed a comprehensive study of the SAR (structure-activity relationships) of this series. The best combination of grass weed activity (Avena fatua L, Setaria viridis (L) Beauv and Alopecurus myosuroides Huds) and wheat selectivity was obtained with an alkoxy group in the 4-position of the phenyl ring. Activity was further enhanced by the presence of tert-butyl on the pyrazole and a methyl group at the C-2 position of the benzoyl moiety. The alkoxy-substituted 3-phenylbenzoylpyrazoles are a novel class of herbicides with potential utility for control of important grass weeds in cereals. 相似文献
58.
Hidetoshi NARA Miho INOUE-MURAYAMA Akiko KOSHIMURA Akinori SUGIYAMA Yuichi MURAYAMA Masami MAEJIMA Yuko UEDA Hideyuki ITO Ettore RANDI Heui-Soo KIM Ji-Hong HA Hitoshi KITAGAWA Yukari TAKEUCHI Yuji MORI Toshiroh IWASAKI Mitsuo MORITA Katuaki ÔTA Shin'ichi ITO 《Animal Science Journal》2005,76(1):81-86
Various dog breeds are remarkably different from each other not only in their sizes and shapes but also in behavioral traits, suggesting that some of these characteristics are under genetic control. However, little is known about genes related to behavioral traits in canine species. In humans, it has been reported that the dopamine receptor D4 gene (DRD4) includes polymorphism at several regions that relate to personality or psychiatric disorders. In an earlier study by the authors of the present study, the polymorphisms in canine DRD4 exon III and exon I regions were reported. In the present study, a novel polymorphism in canine DRD4 intron II was found based on a 17 base pair insertion/deletion, and the two alleles detected were named P (shorter allele) and Q (longer allele). The allelic distribution in 28 breeds of dog, including a total of 1114 unrelated individuals, were then investigated. Both P and Q alleles were detected in most of the breeds investigated; however, the frequencies of P and Q differed greatly between breeds. With respect to classification based on breed origin, P and Q alleles were frequent in Occidental and Oriental breeds, respectively. Furthermore, two subspecies of wolves, the ancestors of dogs, were analyzed for the comparison of allele frequencies with dogs, and the P allele was predominant in both European and Chinese wolves. 相似文献
59.
60.
运用层次分析法和模糊数学综合评判方法,根据石河子、昌吉、吐鲁番等8个地区的无霜期、温度、积温和降水因素,建立了数学模型,并对新疆天然甜型葡萄酒原料种植区域进行了区划研究.结果表明:吐鲁番的综合评价最高,其次为和田,评价值分别为0.97和0.91,属非常适宜种植区;哈密和喀什的评价值分别为0.81和0.87,属适宜种植区;库尔勒的为0.71,属次适宜种植区,而石河子、昌吉和霍城的评价值均小于0.59,属不适宜种植区. 相似文献