西北黄土高原旱区饲草资源利用及草场生产潜力研究

通过对西北黄土高原旱区所属三省一区７８县饲草资源及其利用改良现状的调查研究，结果表明：该区现已超载８７５万个羊单位。文章分析了超载过牧的根源及严重性，并对草场气候生产潜力进行了框算，提出了解决问题和挖掘出生产潜力的基本思路。     

向海湿地景观类型与鸟类多样性季节变化的关系

2010～2011年,在吉林向海国家级自然保护区采用固定半径样点法对春秋两季的鸟类多样性进行了调查,共记录到鸟类114种22 111只次,隶属于14目34科。应用逐步向后回归模型探测春、秋两季不同景观类型与鸟类香农-维纳指数、均匀性指数和物种丰富度指数之间的关系。结果表明,湿地鸟类群落在季节间发生种类结构的显著变化,不同景观类型对不同多样性指数的影响不同,农田会显著减少湿地鸟类多样性,水域和沼泽对香农-维纳多样性有正效应,但是对均匀性和物种丰富度有负效应,距公路较近会减少鸟类春季的均匀性和香农-维纳多样性。     

1960～2010年宜良县降雨量和蒸发量变化特征分析

利用宜良县1960～2010年的年降水量和小型蒸发量资料,采用线性趋势、干燥度等统计学方法,分析近51年宜良县降雨量和蒸发量的变化特征.结果表明,1960～ 2010年宜良县降雨量和蒸发量均在逐年减小,特别是21世纪以来降雨量和蒸发量均减少,可利用水资源较少.宜良县降雨主要集中在5～10月,蒸发主要集中在3～9月,其中3～5月降雨量较少,而蒸发对水的消耗比较明显,气候比较干燥,容易发生春旱;10 ～11月蒸发对水的消耗比较小,而这个阶段降水也比较少,也容易发生秋旱.     

三门峡烤烟中性香气成分的变异分析

以三门峡烟区94个烤烟样品为材料,分析了不同地点、不同品种、不同等级、不同海拔高度、不同土壤类型和不同施氮水平的烤烟中性香气物质含量变化。结果表明：烤烟的关拉德反应产物（22．58±4．72μg／g）、类西柏烷类物质（52．88±32．96μg／g）、类胡萝卜素降解产物（47．96±6．02μg／g）和新植二烯（743．92±200．96μg／g）含量的分布形态为正偏尖峭峰;芳香族氨基酸降解产物（16．91±4．33μg／g）和其他中性香气成分（14．30±2．45μg／g）的分布形态为正偏平阔峰。烤烟中性香气成分含量随着烟区、品种、等级、海拔、土壤类型及施氮水平不同而存在明显变异。     

兴国灰鹅季节性繁殖控制技术研究初报

针对兴国灰鹅存在明显的季节性繁殖特性,采用短光照控制技术,解决了其在自然条件下5～8月份不产蛋的问题,兴国灰鹅的产蛋数显著提高。     

近62年新疆喀什市气温及降水量变化特征分析

利用喀什市气象代表站点1951 ～2012年平均气温、年最高气温、最低气温、降水量等数据资料,分析近62年以来喀什市的气温和降水量变化特征.结果表明,进入21世纪以后该地域气温明显提升,平均气温趋向上升;年平均气温升高率为0.279℃/10a.相比20世纪,近10年的气温变动提升了1.3℃;降水量变动趋势总体上不明显,线性变动倾向率为1.237 mm/10a;62年以来喀什市最高气温上升率与西北地区最高气温上升率保持一致,平均极端最高气温和最低气温同样是趋向升高.近10年的最高气温、最低气温与过去相比,分别上升0.6和1.2℃,对年平均气温的升高贡献最大的是最低气温的提升.     

Aroma profiles of the curry leaf, Murraya koenigii (L.) Spreng. chemotypes: Variability in north India during the year

Murraya koenigii (L.) Spreng. (Rutaceae) is characterized by a large chemical intraspecific variability among the land races. This fact makes it difficult to detect real changes occurring in their essential oil composition during annual cycle. Based on this, variations of essential oil yield and composition in two chemotypes (‘A’ and ‘B’) of M. koenigii were assessed in spring, summer, rainy, autumn and winter seasons under foot hill conditions of northern India. The essential oil yield ranged from 0.15% to 0.18% in chemotype ‘A’, while it varied from 0.12% to 0.14% in chemotype ‘B’. Essential oils of both chemotypes from different seasons were analysed by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). A total of fifty-eight constituents representing 93.7-98.8% of chemotype ‘A’ and fifty-six constituents forming 96.1-98.7% of the total composition of chemotype ‘B’ were identified. Chemotype ‘A’ was characterized by higher percentages of α-pinene (34.6-41.9%), sabinene (26.1-36.1%), (E)-caryophyllene (2.4-5.4%) and terpinen-4-ol (1.5-5.3%), whereas chemotype ‘B’ was dominated by higher amount of α-pinene (52.7-65.3%), β-pinene (10.7-12.9%), (E)-caryophyllene (3.1-10.3%) and limonene (5.1-7.8%). Comparative results showed considerable variations in the essential oil composition of both chemotypes due to season of collection. Present study concluded that the M. koenigii leaves of desired quality may be obtained by selecting suitable chemotype and season.     

Variations in the morphological characteristics of Stipa tenacissima fiber: The case of Tunisia

Esparto fibers are cellulose-based fibers extracted from esparto (Stipa tenacissima) leaves. Morphological characteristics (length, width, and coarseness) of esparto fibers are analyzed in relation to growing conditions and plant biology. Seven localized sites in Kasserine in central western Tunisia are examined. The analysis of variance showed that all investigated characteristics vary significantly with site, season, and leaf level. Leaves reach minimum level in winter and maximum level in fall. Fiber differentiation is closely related to the vegetative cycle. Fibers are short and wide at the leaf base (basal level) and grow longer and thinner above the leaf. Results on the raw material (esparto leaves) were confirmed by results on esparto pulp.     

EMS诱发大豆农艺性状的遗传变异

大豆EMS诱变群体M_2的生育期、株高变异系数大于M_2,而且世代间的相关显著。主茎节数、分枝数和产量性状M_2和M_3的变异系数大致相同。M_3M—M_4各性状的相关值大于M_2—M_3。M_3株系与M_4品系间各性状的相关值高于M_3单株与M_4株系间的相关值。一些性状M_2株系内变异大于株系间变异,另些性状则相反,但M_2株系内变异小于株系间的变异。     

大豆科丰14诱变系主要农艺性状和品质性状变异分析

大豆经过辐照诱变,后代性状会发生一定变异,本试验旨在解析辐照后大豆诱变后代的性状变异规律,为辐射育种的深入研究提供理论支撑;通过对大豆科丰14及其20个辐照诱变系主要农艺性状和品质性状进行测定和分析,结果表明,65%的诱变系生育期延迟7d以上,80%以上的诱变系在株高、主茎节数、茎粗、单株荚数、单荚粒数、百粒重和单株产量等性状上有显著变异,35%的诱变系底荚高度有显著变异,分别有20%、30%和15%的诱变系的蛋白质、脂肪和异黄酮含量变异显著。20个诱变系的农艺性状变异较大,品质性状变异较小;90%诱变系单株产量显著提高,生育期、株高、主茎节数、茎粗、单株荚数和百粒重的增加对产量提高有促进作用,而部分诱变系的单荚粒数和百粒重减少又会在一定程度上制约着产量提高;大部分诱变系蛋白质含量呈下降趋势,脂肪含量呈上升趋势,而异黄酮含量的变异与各性状之间无明显关系。