不同水分环境下玉米叶面积QTL定位及候选基因分析

玉米叶面积的大小及分布特征不仅影响其光合效率、蒸腾速率,而且与其耐旱性、耐密性、抗倒伏性及产量形成紧密相关。深入剖析不同水旱环境下玉米不同生育时期不同叶位叶面积的分子遗传机理对玉米耐旱高产新品种的选育具有重要意义。本研究以构建的2套F_2∶3群体为试材,在8种水分环境下,采用复合区间作图法（CIM）和基于混合线性模型的复合区间作图法（MCIM）对玉米相应叶（V₁₈时期第10片叶、R₁时期穗三叶）叶面积进行单环境和多环境联合QTL分析;参考玉米基因组B73 RefGen_v3挖掘稳定表达的QTLs （sQTLs）区间内的候选基因,并对其进行功能分析。结果表明,采用CIM法,单环境下2个生育时期2套F_2∶3群体间总共定位到了7个玉米相应叶叶面积QTLs,主要受显性（81.0%）、部分显性（14.3%）和超显性（4.7%）等遗传效应的调控,其中在干旱环境下定位到了5个QTLs。采用MCIM法,在2套F_2∶3群体间总共检测到6个相应叶叶面积的联合QTLs,其中1个表现为显著的QTL与环境的互作（QTL×E, Bin 2.08~2.09）,1对QTLs （Bin 1.08~1.10与 Bin 2.08~2.09）参与了显著的加性与加性（AA）上位性互作。结合CIM和MCIM法进一步分析在2套F_2∶3群体间检测到了6个sQTLs,其分别位于Bin 1.08~1.10、Bin 2.08~2.09、Bin 4.08~4.09、Bin 6.05、Bin 8.03和Bin 10.03处,并在这些sQTLs区间内确定了12个玉米叶发育相关候选基因。采用生物信息学,总共收集了75个玉米叶发育相关候选基因,通过系统进化树分析表明,这些候选基因划分为3大进化分支,且上述检测到的12个候选基因分布于这3大进化分支上。这些结果为系统地解析玉米不同生育时期不同水旱环境下相应叶叶面积的分子遗传机理提供理论依据,检测到的sQTLs可作为叶面积改良的重要染色体区段,检测到的候选基因为其进一步克隆、功能分析及育种应用提供了信息参考。     

高产棉花太阳辐射能利用率及干物质分配规律研究

通过对1988～1989年高产棉花栽培试验结果进行分析发现,棉花的太阳辐射利用率在叶面积系数小于2.0时随叶面积系数的增加而线性增加,大于2.0时增加变缓。从生育时间看,7月中旬前太阳辐射利用率指数上升,7月中旬至8月底相对稳定在1.2～1.4克/兆焦左右,9月以后又不同程度线性下降。生长季内子棉太阳辐射经济效率1988和1989年分别为0.14和0.15克/兆焦。收获指数与最大叶面积系数呈显著负相关;盛花期之前棉株各器官之间的同伸关系或明显,盛花期后器官的生长相互间无明显的确定性关系。如能调节密度与叶面积系数的关系,使得既提高5～6月的辐射能利用率,同时使7～8月叶面积系数维持在3.0～3.5的适宜范围内,9～10月群体又不早衰,则有利于获得高产。     

Evaluation of effects of olfactory and auditory stimulation on separation anxiety by salivary cortisol measurement in dogs

Separation anxiety (SA) is a serious behavioral problem in dogs. In this study, salivary cortisol was studied to determine if the owner''s odor or voice could reduce SA in dogs. Twenty-eight dogs with SA were divided into three groups: group 1 (control), group 2 (with owner''s clothes during the separation period; SP) and group 3 (a recording of the owner''s voice was played during SP). The dog''s saliva was collected after the owner and their dog were in the experimental room for 5 min (PRE). The dog was then separated from the owner for 20 min and saliva collected four times at intervals of 5 min (SP1–4). Finally, the owner was allowed back into the room to calm the dog for 5 min, after which saliva was collected (POST). Evaluation of salivary cortisol concentrations by ELISA revealed that the ratios of SP1 concentration to PRE or POST concentrations were significantly higher in group 1 than in group 2 or 3. Additionally, the concentrations of SP1–PRE and SP1–POST among groups differed significantly. These findings indicate that the owner''s odor or voice may be helpful to managing stress in dogs with SA.     

Physiological response of one of South Africa’s premier freshwater sport angling species,the Orange-Vaal smallmouth yellowfish Labeobarbus aeneus,to catch-and-release angling

The practice of catch-and-release fishing has been widely promoted by angling fraternities as a fisheries manage- ment tool. The aim of this investigation was to determine the physiological response of Orange-Vaal smallmouth yellowfish, Labeobarbus aeneus, to catch-and-release angling in the Vaal River, South Africa. Fish were collected using standard fly-fishing techniques, anaesthetised in clove oil and blood was drawn from the caudal vein; thereafter the fish were weighed, measured, revived and released. Blood plasma was analysed for concentra- tions of glucose, cortisol and lactate to determine the effects of angling duration, fish size and water tempera- ture. Larger fish were angled for a longer duration compared with smaller fish. Levels of glucose were affected by water temperature (influenced by time of year). Plasma glucose concentrations decreased with greater angling duration. Few individuals (n = 12) showed increased plasma cortisol concentrations. In extended-capture fish (angled for >1 min), lactate concentrations increased significantly above values for rapid-capture fish (angled for >30 s). These data suggest that catch-and-release causes physiological stress to fish, but nonetheless this practice can be a valuable fisheries management tool to ensure the sustainability of fish populations. Other factors beyond the ‘angling’ time are likely to contribute to physiological disruptions in homeostasis and therefore handling and air exposure of angled fish should be included in future catch-and–release angling studies. In addition, the longer-term impact of angling on fish health should also be determined.     

Comparison of tracheal aspirates before and after high-speed treadmill exercise in racehorses

OBJECTIVE: To determine whether percentages of neutrophils in tracheal aspirate (TA) samples collected from racehorses are increased after exercise and whether interpretation of results from TA samples taken before and after exercise agree. DESIGN: Case series of 40 young Thoroughbred and Standardbred racehorses in race training presented for evaluation of poor performance. PROCEDURE: TA samples were collected endoscopically from racehorses presented for poor performance 24 h before and 1 to 2 h after high speed treadmill exercise testing. Aliquots of the retrieved fluid were cytocentrifuged and smears were stained with Diff-Quik. Mean neutrophil counts were expressed as percentages of the total number of inflammatory cells counted and subsequently were categorised as either above or below an accepted cut-off of 20%. Comparisons between percentages of neutrophils before and after exercise were made. RESULTS: Percentage of neutrophils from TA samples obtained from racehorses after exercise was significantly higher than neutrophil percentages from TA samples collected from the same horse before exercise. In horses with TA specimens that were categorised as having < or = 20% neutrophils before treadmill exercise, the percentage of neutrophils in their TA specimens after exercise was, on average, significantly higher and was greater than the cut-off value of 20%. CONCLUSION: Recent strenuous exercise may change the proportion of neutrophils in lower airways of racehorses and practitioners should be aware of this when collecting and interpreting the results from TA samples. The most practical time for collection of a TA sample to obtain the most diagnostically useful information might be after a suitable washout period of at least 1 to 2 h post-exercise.     

灌木抗旱机理研究

从灌木生长性状、形态结构、细胞质膜透性、光合、渗透调节(可溶性糖、脯氨酸、甜菜碱和无机离子)、ABA和LEA蛋白变化及其与灌木抗旱性的关系方面,综述了灌木抗旱机理研究.     

TeMV与PWV侵染对西番莲代谢生理及组织微结构的影响

以西番莲品种‘台农1号’为实验材料,通过电镜扫描技术比较观测TeMV和PWV侵染与健康西番莲的叶片、幼嫩果实外果皮组织形态结构,分析测定其叶片生理生化变化,研究西番莲病毒侵染对西番莲叶片和幼嫩果实外果皮组织结构和生理生化的影响。结果表明：TeMV与PWV侵染后,西番莲植株叶片的海绵组织细胞间隙缩小,发生成团堆积状排列,栅栏组织细胞萎缩,呈不规则长条形;幼嫩果实外表皮组织中石细胞层发生严重断裂,排列松散,海绵层细胞变得松散,且发生较严重的木质化现象;叶片与幼嫩果实外表皮表面纹理粗糙、褶皱,气孔保卫细胞萎缩,气孔周围组织皱缩、粗燥;感病果实外果皮表面上的腺毛凸起无序。病毒侵染后,感病植株第1～3叶的蔗糖含量较第4～6叶的高23.11%;健康叶片则相对平衡,降低了淀粉积累、PG酶、纤维素酶与PPO酶活性,提高了感病植株第1～3叶的α-淀粉酶、GS酶与POD酶活性。西番莲受TeMV与PWV侵染后,植株叶片第1～6叶营养物质分配不平衡,相关物质的合成分解与抗氧化防御酶系统受伤害,叶片与果实组织形态结构受到不同程度的损坏,植株正常吸收功能遭到破坏。     

安徽药用牡丹炭疽病病原菌鉴定

<正>牡丹(Paeonia suffruticosa Andr.)是芍药科植物,为多年生落叶灌木,具有很高的观赏和药用价值。因其风姿华丽、色彩艳丽、品种繁多、深受大家喜爱,是中国传统名花和世界著名花卉之一。其根皮也被称为丹皮,具有抗炎、抑制血小板、止痛、清热等作用,是六味地黄丸等著名中成药的主要配方,也是饮片中的常用品[1-2]。近年来,随着牡丹种植面积的不断扩大,造成牡丹病害的大面积发生,已给牡丹生产带来严重影响。     

2019—2020年苏浙皖三省小麦叶锈菌群体的致病类型鉴定及毒性结构分析

为持续控制小麦叶锈病及促进小麦的抗叶锈病育种工作,2019—2020年自江苏、浙江和安徽3个省采集自然感叶锈病的小麦病叶,经分离获得小麦叶锈菌单孢分离物,利用43个小麦叶锈病鉴别寄主材料对其致病类型进行鉴定,并对其毒性结构进行分析。结果显示,从170份小麦叶锈菌单孢分离物中共鉴定出67个致病类型,主要致病类型为THS、SHJ、PHS和SHS,出现频率分别为8.8%、7.6%、5.9%和5.9%。江苏、浙江和安徽3个省的单孢分离物对携带抗叶锈基因Lr10、Lr12、Lr22a、Lr22b、Lr29、Lr33、Lr35和Lr36的鉴别寄主材料的苗期毒性频率均超过90.0%,而对携带抗叶锈基因Lr9、Lr24、Lr25、Lr28、Lr38、Lr40、Lr41、Lr42、Lr43和Lr13+3ka的鉴别寄主材料的苗期毒性频率均小于10.0%。卡方检验及Fisher精确检验显示,3个省小麦叶锈菌群体对抗叶锈基因Lr1、Lr2a、Lr3、Lr14b、Lr18、Lr21、Lr26、Lr27+31、Lr32和Lr37的毒力存在显著分化。浙江省小麦叶锈菌群体具有较少的毒性因子（4.73）和毒性值（600...