壶瓶山自然保护区华南虎野外调查及栖息地评价

湖南省壶瓶山是森林和野生动物类型的国家级自然保护区,是近几年发现华南虎Panthera tigris amoyensis证据较多的区域.中美华南虎联合调查队于2001年10～12月采用访问调查法、样带调查法、痕迹调查法和红外线自动照相技术等目前国际国内通用的方法和技术,对该保护区进行了调查.此次调查虽未得到华南虎存在的确切证据,但较系统地调查了该区域的生境状况,初步评价了华南虎的生存环境.该区域历史上是华南虎分布较多的区域.经分析,目前仍具备华南虎生存的基本条件,是以后实施华南虎重引入工程较为理想的试验基地.表2参13     

水稻品种光、温反应特性在杂种F_1的表现

本研究于1977年在雅安市本校农场,就五个光、温反应特性不同品种:DissiD52/37、矮脚南特、矮子占、71—56、IR_8作亲本,采用非限定半双列杂交获得10个杂种F_1,对其高温短日生育期、短日促进率(短日敏感性),高温促进率(感温性)进行了测定。结果(1)短的高温短日生育期在杂种F_1表现呈完全显性或超亲显性;(2)在适温条件下,短日促进率(短日敏感性)高的,在杂种F_1表现为完全显性或超亲显性。并观察到在适温以下低温条件,明显抑制了短日敏感性的表现;(3)在自然日照下,高温促进率低的特性,杂种F_1表现为完全显性,而在短日处理下结果恰相反,即高温促进率高的为完全显性或超亲显性。另外,讨论了水稻品种光、温特性之间的相互制约关系。     

家蚕新品种夏芳×秋白的试验与推广

经过小区试验,夏芳×秋白比(苏_3·秋_3)×(苏_4·苏_12)在结茧率、万头蚕产茧量、全茧量、茧层率等成绩方面略优于苏字号.夏芳×秋白与黄鹤×朝霞的试验成绩,经方差分析,其结茧率、克蚁产茧量、万头蚕收茧量在品种间差异极其显著,全茧量差异也达到了显著水平.中试成绩显示:无论是1994年秋还是1997年秋,夏芳×秋白的单产成绩大大优于(苏_3·秋_3)×(苏_1·苏_12),两年单产分别增产57.6%和46.1%.通过对中试控制点调查数据的方差分析,品种间和季节间的单产差异都达到了极显著水平,尤其是品种间的差异大大超过了极显著水平.干茧的缫丝成绩是:夏芳×秋白的光折比(苏_3·秋_3)×(苏_4·苏_12)少8.05公斤,出丝率高3.19%.     

竹类一新种及一些新组合和新分布

本文报道了竹亚科苦竹属一新种,它被命名为花石竹,产于中国湖南省。对一些栽培变种做了新组合,补充了新分布。     

Ability of chromosome 4H to compensate for 4D in response to drought stress in a newly developed and identified wheat–barley 4H(4D) disomic substitution line

A spontaneously developed wheat–barley 4H(4D) disomic substitution line was identified cytogenetically using genomic in situ hybridization (GISH), multicolour fluorescent in situ hybridization (FISH) and microsatellite markers. The ability of the barley 4H chromosome to compensate for wheat 4D in response to mild drought stress was also investigated. In the barley cv. 'Betzes' and the 4H(4D) substitution line, mild osmotic stress induced intensive stomatal closure, resulting in reduced water loss through transpiration and unchanged relative water content in the leaves. As the CO₂ assimilation rate remained relatively high, the water use efficiency, which is an important factor associated with drought tolerance, increased extensively under mild osmotic stress in these lines. In the case of the parental wheat genotypes, however, mild drought stress induced less intense stomatal closure and a greater decrease in the CO₂ assimilation rate than in barley or in the substitution line, resulting in unaugmented or reduced water use efficiency. The results demonstrate that genes localised on the 4H chromosome of barley were able to increase the water use efficiency of the wheat substitution line, which is suitable for improving wheat drought tolerance through intergeneric crossing.     

Subsurface drip irrigation and reclaimed water quality effects on phosphorus and salinity distribution and forage production

In the Canary Islands, water scarcity is one of the constraints for agricultural activity. Non-conventional water resources generally represent more water volume than conventional ones. The distribution of these resources frequently permits the possibility of a conjunctive use of desalinated (DW) water and reclaimed municipal wastewater (RW). Field testing with both water qualities and different irrigation systems is necessary for optimal site-specific management. The objective of this work was to evaluate soil salinity and phosphorus distribution, and alfalfa yield in a 20 month field experiment carried out in the island of Gran Canaria, using municipal RW and freshwater (FW) under subsurface drip irrigation (SDI). Phosphorus speciation was performed both in irrigation waters and in soils (Olsen's inorganic, organic, and microbial). RW had large EC values (2.4 dS m⁻¹) with a remarkable nutrient load contribution and an average total P around 3 mg L⁻¹, predominantly hydrolysable forms, while FW had very low salinity and negligible amounts of P. For the RW treatment a salt gradient was established, causing plant mortality between the irrigation lines. The study of P speciation allows describing P distribution and plant uptake in terms of P forms. Large values of microbial P were produced for the two irrigation waters around the emitters, especially for FW.A faster P-cycling could have contributed to the significantly larger inorganic P contents observed in FW irrigated soils, in spite no external sources were added by the irrigation water.     

高效液相色谱法测定油茶肉质果、肉质叶的维生素C

用高效液相色谱法测定油茶肉质果、肉质叶维生素C的含量.采用YWG-C18(10μm,4.6mm×250mm i.d.)色谱柱,以0.02 M醋酸钠缓冲液-甲醇为流动相,在254 nm波长下检测.回收率为:94.8%～101.2%.相对标准偏差小于2%.     

韭菜迟眼蕈蚊紫外敏感视蛋白基因的克隆及光强度对其表达量影响

为明确韭菜迟眼蕈蚊Bradysia odoriphaga紫外敏感视蛋白基因Bo-uv的作用及其与趋光性的关系,利用常规PCR方法克隆获得Bo-uv基因的全长cDNA序列,分析了其敏感视蛋白的氨基酸序列与其它12种昆虫同源蛋白氨基酸序列之间的系统进化关系,运用qPCR技术检测了不同发育阶段、不同组织及不同光强度下Bo-uv基因的相对表达量。结果表明,Bo-uv基因cDNA全长2 757 bp,开放阅读框1 542 bp,编码514个氨基酸。韭菜迟眼蕈蚊紫外敏感视蛋白的氨基酸序列与其它12种昆虫同源蛋白的氨基酸序列一致性为21.93%～43.00%,与橘小实蝇Bactrocera dorsalis的氨基酸序列同源性最高。Bo-uv基因在韭菜迟眼蕈蚊蛹末期、成虫期表达,在成虫头部的相对表达量较高。在0～10 000 lx光强范围内雌、雄成虫体内该基因的相对表达量均呈先增高后降低趋势。与对照相比,1 000 lx光强度下其相对表达量显著升高,10 000 lx时相对表达量显著降低。表明光强度能够有效地调控Bo-uv基因的表达,该基因在韭菜迟眼蕈蚊感知外界光刺激过程中具有重要作用。     

SPA的实验室制备及标记技术

ＳＰＡ具有与ＩｇＧＦＣ段非特异性结合的生物学特性，这一特性使其在免疫学研究中有重要的作用，根据应用目的不同，ＳＰＡ制剂分为三类：菌体试剂、ＩｇＧ－ＳＰＡ、可溶性纯化ＳＰＡ。本文将介绍这三种试剂的实验室制备方法及ＳＰＡ的ＦＩＴＣ、ＨＲＰ、１２５Ｉ的标记技术。     

运用PPR方法探讨星天牛与公园植物群落之间的关系

本研究运用投影寻踪回归（ＰＰＲ）方法对上海市７个样地的实际调查数据进行分析。结果表明：星天牛对寄主的危害率与寄主及周围植物的密度有密切关系。通过模拟试验，可寻求星天牛发生发展与植物群落之间的数量关系。从而为园林部门对星天牛进行综合治理，制定符合经济及生态规律的管理方案以及园林设计，提供了科学依据。