大白菜对氮素响应的基因型差异及相关特征分析

为明确大白菜主产区主推品种对氮素响应的特征及基因型差异,筛选氮高效大白菜种质资源,探讨大白菜氮效率及氮敏感度的评价指标,以我国栽培面积和生产供应数量最大的蔬菜作物大白菜为研究对象,以目前主产区主推的68份代表性品种为试验材料,采用田间试验方法,于成熟期对开展度、株高、毛质量、外叶数、球质量、球高、球宽、球叶数、最大叶长、最大叶宽、中肋长、中肋宽、中肋厚、中心柱长和中心柱宽共15个在生产中关注的重要农艺性状及含氮量、氮农学利用效率和氮响应度3个氮效率性状在2种氮素水平(正常供氮,N:270 kg/hm~2;低氮,N:54 kg/hm~2)进行了详细调查、计算和分析,对各性状在2种氮水平下的相对值进行了计算,并对大白菜氮效率类型和氮敏感度进行了评价和划分。结果表明,除外叶数和中心柱长之外,其他13个农艺性状在2种供氮水平下均存在极显著差异,氮水平对大白菜重量性状的影响最大,对抽薹性相关的性状影响最小,大白菜的含氮量和氮农学利用效率在不同氮水平下也存在显著差异;各农艺性状在相同氮处理条件下均存在极显著的基因型差异,其中中心柱长在品种间变异系数最大;含氮量、氮农学利用效率和氮响应度也存在显著的基因型差异,其中氮响应度的变异系数最大;根据2种供氮水平下的产量,将供试大白菜品种分为4种氮效率类型,即双高效型、高氮高效型、低氮高效型和双低效型;根据相对产量和氮响应度,将68份大白菜品种分为4种氮敏感型,即氮不敏感型、氮低度敏感型、氮中度敏感型和氮高度敏感型。综合2种评价标准,可更清楚了解不同大白菜品种的氮素响应特征,为进一步研究大白菜氮高效利用的分子机制及选育氮高效大白菜新品种奠定基础。     

补植改造对大兴安岭白桦低质林土壤养分的影响

对大兴安岭林区新林林业局白桦低质林进行不同密度的补植改造,采用灰色关联分析法和变异系数法对各补植改造样地的土壤养分进行分析。结果表明:7个补植样地的灰色关联值,从大到小依次为BZ5(0.886)、BZ6(0.794)、BZ4(0.681)、BZ3(0.651)、BZ2(0.582)、BZ1(0.577)、CK(0.547)。与对照样地相比,补植改造后各样地的土壤养分均有不同程度的提高,且随着补植密度的增大,土壤养分先增大后减小,其中BZ5样地的灰色关联度最高,表明补植密度为900株·hm~(-2)的改造方式最有利于土壤养分的积累,适宜大兴安岭白桦低质林的补植改造。     

Identification of an ice recrystallisation inhibition gene family in winter‐hardy wheat and its evolutionary relationship to other members of the Triticeae

Ice recrystallisation inhibition (IRI) proteins are important for plants that exist in cold environments. Six novel genes encoding IRI proteins were isolated from winter‐hardy wheat (Tricticum aestivum) cultivar (Mironovskaya808). Conserved domain analysis confirmed that all the predicted proteins contained the basic characteristics of IRI proteins, including leucine‐rich repeats (LRR) and IRI‐domains (NxVx_1‐2G). In addition, these proteins possessed an N‐terminal signal peptide and some conserved cysteines. Despite the high conservation of the amino acid sequences, the characteristic regions still exist among these IRI‐domains of IRI sequences. All IRI sequences in this study are highly homologous with phytosulfokine receptors (PSR). Quantitative real‐time PCR (qPCR) analysis indicated that each member of the IRI gene family was induced after exposure to low temperature. Heterologous expression of IRI proteins enhanced freezing tolerance in host cells. A total of 28 IRI genes were isolated from Triticeae, and the evolutionary relationship of the IRI gene family in Triticeae and related species showed high interspecific specificity. The IRI genes from Aegilops, which is one of the progenitors of allohexaploid wheat, shared the closest relationship with those from Triticum. With high interspecific specificity in Triticeae, however, there was no specificity among different species of Triticum. Our results suggest that IRI genes have potential value to improve cold resistance of crops.     

珍珠鸡和白头鹤体内两种吸虫的形态鉴定

对采自哈尔滨北方森林动物园珍珠鸡肝脏和白头鹤盲肠的两种吸虫采用苏木素染色法制成装片,观察结构,显微测量,进行形态学鉴定。结果表明珍珠鸡肝脏内吸虫为东方次睾吸虫,白头鹤盲肠内虫体为卷棘口吸虫。这两种寄生虫均为国内宿主新记录。     

利用水生蔬菜治理水体污染的建议

利用生态浮床技术、水生植物滤床技术种植水生蔬菜是治理水体富营养化污染的有效途径,建议让农民成为应用水生蔬菜治理水体富营养化污染的主体和受益者,实现治理水体污染的可持续发展.     

Mowing Height and Mowing Frequency Interactions on Turf Performance of Kentucky Bluegrass

The mowing height and mowing frequency are the key factors that affect the turf quality and turfgrass growing ability. The purpose of this study was to reveal the alternative efficient interaction between mowing height and mowing frequency in Kentucky bluegrass turf management. The Kentucky bluegrass cultivar 'Kenblue'(Poa pratensis L.) was used to evaluate the interactions of mowing heights(H1, H4 and H7) and mowing frequencies(F2, F5 and F8) on the performance of turfgrass and turf physiological responses under the field condition. The results showed that the treatment of H7×F8 had perfect influence on the turf texture, root elongation, and also enhanced soluble sugar and free proline content in plants. While, the turf quality, color, uniformity and the increasing tiller numbers were performed more superior in the treatment of H4×F5 than other treatments. In all the interacting treatments, the relation between leaf green index and number of shoots(dm~2) was positively correlated, thus, it could be speculated that the proper mowing height with frequency had a strong impact on the increasing of turfgrass tillers. On the whole, the interaction of H4×F5 on turf quality was the most excellent treatment in this experiment.     

浅析矿山项目建设对林业及环境的影响及治理措施

矿山项目建设对林业及其环境产生了一系列负面影响,包括生态环境破坏、大气污染、水污染、固废等。因此矿山建设应根据自身特点制定行之有效的环境治理措施,打造绿色矿山、和谐矿山。     

试论东部县域扶贫模式与对云南扶贫的借鉴意义———以浙江省江山市为例

由于区域发展不平衡，我国贫困人口绝对基数依旧较大，因此扶贫任务任重道远。浙江省是中国经济发达地区，在扶贫上率先创造了境内无国家级贫困县的历史，县域扶贫模式别具一格，本文通过对浙江江山县域扶贫模式的探析，阐述扶贫工作的一般理论要结合村情，因地制宜，践行本土化扶贫模式，同时为云南省扶贫提供一些借鉴。     

果园实生苗精密播种机覆膜机构的设计研究

根据农艺要求,对本实验室设计的果园实生苗木精密播种机覆膜机的挂膜和压膜机构进行了研究,使该机在覆膜的高度和宽度上可实现调节,以适应不同大小的地块和地膜。铺膜试验表明,该机运行平稳可靠,覆膜效果好,为在寒冷的初春季节实现果园实生苗直播及节约用水量提供了可靠的支持。     

新疆荒漠地区不同灌溉方式造林应用的综合评价

为了全面、客观、准确地掌握不同灌溉方式的造林应用效果,为林业造林技术应用的前景提供理论依据,以Groasis Waterboxx-灌溉系统与漫灌、无灌溉3种灌溉方式为研究对象,依托野外数据,建立不同目标指标的评价指标体系,利用模糊综合评价法对Groasis Waterboxx-灌溉系统与漫灌、无灌溉3种方式在新疆荒漠地区造林中的应用效果进行了计算分析,结果表明:Groasis Waterboxx-灌溉系统效果综合评价值为0.90,Waterboxx这一项高新技术的应用前景良好,值得推广。