动物生理学虚拟仿真实验在生物技术专业学生培养中的应用及其重要性

文章分析了动物生理学虚拟仿真实验在生物技术专业学生培养中的重要性。首先介绍了动物生理学虚拟仿真技术的特点及其优势；然后结合实例阐述了动物生理学虚拟仿真实验在生物技术专业学生培养中的应用，包括提高学生的实验操作能力、深化学生对生理过程的理解，以及培养学生的科学研究思维能力等；最后指出了动物生理学虚拟仿真实验在生物技术专业学生培养中存在的不足和未来的发展方向。文章为教育教学改革提供了思路和借鉴，同时为动物生理学虚拟仿真实验技术的发展进行了一个全面且深入的分析。     

中国生理学会比较生理学专业委员会召开2008年工作会议

2008年10月18日,中国生理学会比较生理学专业委员会在北京大学生命科学学院召开了2008年工作会议。会议由中国生理学会比较生理学专业委员会主任委员王世强教授主持,南京大学王建军教授、浙江大学陈学群教授、华中师范大学陈其才教授、兰州大学陈强教授、华南师范大学李东风教授、军事医学科学院基础所吴丽颖教授、辽宁师范大学邹伟教授等比较生理学专业委员会委员出席了会议,     

为农服务是植物生理学的重要任务

植物生理学是合理农业的基础,近数十年来,由于其他学科向植物生理学渗透,不断开拓新的研究领域,其理论意义及其应用范围已不限于农业。尽管如此,植物生理学为农服务,应是植物生理学的主要方向,也是植物生理学作为基础理论学科而存在的强大的生命力之所在。     

国外植物生理学及与其有关的主要期刊介绍

植物生理学文献源远流长,浩如烟海。随着植物生理学研究的发展和不断深入,其文献量更是与日俱增。植物生理学文献又具有离散的特点。据统计,它散见于综合性自然科学、化学、普通生物学、细胞学、遗传学、生物化学、生物物理学、植物学、植物生理学、微生物学、农学、林学和园艺学等多种学科的数以千计的期刊上。但是,大量的     

芝麻素研究进展

芝麻素是存在于芝麻种子和芝麻油中的木脂素类化合物中的一种,已从多种植物中分离出来。芝麻素具有较强的抗氧化活性,在生物体内具有降低血清胆固醇、调节脂质代谢、稳定血压和抗癌等多种生理学活性。本文综述了芝麻素的天然来源、分离检测方法及其生理学活性等方面的研究现状。     

植物生理学课程体系改革的初步尝试

1　改革的必要性植物生理学是研究植物生命活动规律的科学 ,是生命科学的重要组成部分。作为合理农业的基础 ,植物生理学为世界农业的发展做出了巨大的贡献。它一直是高等农林院校中 ,农学、林学、园艺、土化及植保等专业的重要专业基础课 ,处于生物系列课程的中心位置。但是 ,近年来植物生理学的发展出现了一些新趋势 ,其最显著的特点是分子生物学异军突起 ,并以其强大的生命力迅速渗透到生命科学的各个领域 ,而植物生理学首当其冲 ,对植物生理学的课程设置和教学内容产生了巨大的影响。此外 ,2 1世纪的农业将会以生命科学为基础 ,以产业化…     

《应用植物生理学》导论

1.植物生理学的历史及发展趋势“应用植物生理学”是植物生理学的分支学科,它是通向植物生产的“桥梁”,在讨论《应用植物生理学》前,回顾植物生理学的历史、现状和趋势是有必要的。一切知识都来自实践,远在科学的植物生理学诞生之前,人们通过农业生产实践,总结出有关环境对植物生命活动的影响及其控制的朴素经验,悠久农业历史的我国在这方面有其贡献。古籍中记载有用各种汁液和粪水处理种子“溲种法”和“粪种法”等,起到催芽、防虫、壮苗、抗寒和抗旱的效果。在改     

加强树木生理学研究 早日实现林业现代化

读了“通讯”上刊的“植物生理学如何为四化服务”的文章后,启发很大、深有感触。尤其读了吴克贤和龚垒两位同志有关树木生理学现状和发展的文章后,收获更大。和农作物相比,树木生理学的研究显得发展较慢,存在一定的差距。下面想谈谈对如何加强树木生理学研究的一些粗浅看法。     

试谈国内现行植物生理学教材体系

文革后,我国相继出版了曹家巽、吴相钰合编的《植物生理学》,潘瑞炽、董愚得合编的《植物生理学》,北京农业大学主编的《植物生理学》,北京林学院主编的《植物生理学》,杨学荣主编的《植物生理学》等。这些教材在基础理论的阐述方面,在教材内容的更新和理论联系实际等方面都做的比较好。为恢复我国高等院校植物生理数学秩序,完成教学任务,提高教学质量等方面起到了积     

医学专科学校生理学教学发展浅析

教学方法是生理学教学质量和效果的直接影响因素,是教师实现生理学教学目标和目的的基本保证。文章从当前医学专科学校生理学教学现状出发,指出当前生理学教学中存在的问题,并提出解决问题的对策。     

Does hydraulic lift or nighttime transpiration facilitate nitrogen acquisition?

Water movement from roots to soil at night in the process of hydraulic lift (redistribution) rehydrates the rhizosphere and has been proposed to improve plant nutrient acquisition. Another process that has now been found in many plant species is nighttime transpiration and this could also affect nutrient relations by influencing supply of mobile nutrients to roots at night. The effects of these soil/root water relations interactions have not been adequately tested. We chose ten Sarcobatus vermiculatus (Hook.) Torrey shrubs with different magnitudes of hydraulic lift (i.e. diel range in soil water potential) to test the hypothesis that the magnitude of lift would be positively related to the amount of nitrogen (N) uptake over a period of days. A ¹⁵N tracer was injected in the 20–30 cm soil layer at locations with hydraulic lift to determine plant ¹⁵N acquisition by shallow roots conducting hydraulic lift. Half of the plants were also placed in large humidified tents (i.e. “bagged”), which suppressed nighttime transpiration, and thus were expected to have greater magnitudes of hydraulic lift, although they did not. All plants took up the ¹⁵N tracer, but contrary to our hypothesis the magnitude of hydraulic lift had no significant effect on the amount of ¹⁵N acquired over a 9-day period following labeling. However, plants that were bagged tended to have lower ¹⁵N acquisition (P = 0.07). These data indicate that decreased nighttime transpirational water loss or some other effect of bagging may decrease nutrient acquisition by these nutrient-limited phreatophytic shrubs and more generally suggests a possible nutritional benefit of nighttime transpiration by plants. This suggestion needs more thorough testing to elucidate an important potential link between plant water and nutrient relations.     

干旱区水力提升的生态作用

水力提升是某些植物通过深层根系从较湿的深层土壤中吸取水分再通过浅层根系在较干的浅层土壤中释出的过程。水力提升所释出水量及其释出过程具有积极的生态学意义,它不但为伴生植物提供新的水源、改善其邻近植物的蒸腾作用、缓解水分亏缺、提高水分利用效率．而且促进植物的养分吸收、促进上层干土中分解、硝化和矿化等生化过程．尤其是发生在克隆植物植株间的水分共享这种特殊的水力提升,还影响群落的形成。然而,对于一般的水力提升而言,水力提升所释出水量到底有多少。其生态学作用有多大．有待深入研究。结合研究实践认为．要研究水力提升具有多大的生态学作用．必须准确地区分水;勺提升的水量和毛管水的上升水量。还建议了研究水力提升新的研究方法。     

Hydraulic lift: consequences of water efflux from the roots of plants

Hydraulic lift is the passive movement of water from roots into soil layers with lower water potential, while other parts of the root system in moister soil layers, usually at depth, are absorbing water. Here, we review the brief history of laboratory and field evidence supporting this phenomenon and discuss some of the consequences of this below-ground behavior for the ecology of plants. Hydraulic lift has been shown in a relatively small number of species (27 species of herbs, grasses, shrubs, and trees), but there is no fundamental reason why it should not be more common as long as active root systems are spanning a gradient in soil water potential (Ψ_s) and that the resistance to water loss from roots is low. While the majority of documented cases of hydraulic lift in the field are for semiarid and arid land species inhabiting desert and steppe environments, recent studies indicate that hydraulic lift is not restricted to these species or regions. Large quantities of water, amounting to an appreciable fraction of daily transpiration, are lifted at night. This temporary partial rehydration of upper soil layers provides a source of water, along with soil moisture deeper in the profile, for transpiration the following day and, under conditions of high atmospheric demand, can substantially facilitate water movement through the soil-plant-atmosphere system. Release of water into the upper soil layers has been shown to afford the opportunity for neighboring plants to utilize this source of water. Also, because soils tend to dry from the surface downward and nutrients are usually most plentiful in the upper soil layers, lifted water may provide moisture that facilitates favorable biogeochemical conditions for enhancing mineral nutrient availability, microbial processes, and the acquisition of nutrients by roots. Hydraulic lift may also prolong or enhance fine-root activity by keeping them hydrated. Such indirect benefits of hydraulic lift may have been the primary selective force in the evolution of this process. Alternatively, hydraulic lift may simply be the consequence of roots not possessing true rectifying properties (i.e., roots are leaky to water). Finally, the direction of water movement may also be downward or horizontal if the prevailing Ψ_s gradient so dictates, i.e., inverse, or lateral, hydraulic lift. Such downward movement through the root system may allow growth of roots in otherwise dry soil at depth, permitting the establishment of many phreatophytic species. Received: 2 June 1997 / Accepted: 24 September 1997     

An assessment of diurnal water uptake in a mesic prairie: evidence for hydraulic lift?

Hydraulic lift, the passive movement of water through plant roots from wet to dry soil, is an important ecohydrological process in a wide range of water-limited ecosystems. This phenomenon may also alter plant functioning, growth, and survival in mesic grasslands, where soil moisture is spatially and temporally variable. Here, we monitored diurnal changes in the isotopic signature of soil and plant xylem water to assess (1) whether hydraulic lift occurs in woody and herbaceous tallgrass prairie species (Rhus glabra, Amorpha canescens, Vernonia baldwinii, and Andropogon gerardii), (2) if nocturnal transpiration or grazing by large ungulates limits hydraulic lift, and (3) if a dominant grass, A. gerardii, utilizes water lifted by other tallgrass prairie species. Broadly, the results shown here suggest that hydraulic lift does not appear to be widespread or common in this system, but isolated instances suggest that this process does occur within tallgrass prairie. The isolated instance of hydraulic lift did not vary by grazing treatment, nor did they result in facilitation for neighboring grasses. We suggest that the topographic complexity of this tallgrass prairie and the high rates of nocturnal transpiration observed in this study likely limit the frequency and occurrence of hydraulic lift. These results suggest that hydraulic lift can be a patchy process, particularly in heterogeneous landscapes.     

Hydraulic lift among native plant species in the Mojave Desert

Hydraulic lift was investigated among native plants in the Mojave Desert using in situ thermocouple psychrometers. Night lighting and day shading experiments were used to verify the phenomenon. Hydraulic lift was detected for all species examined: five shrub species with different rooting depths and leaf phenologies and one perennial grass species. This study was the first to document hydraulic lift for a CAM species, Yucca schidigera. The pattern of diel flux in soil water potential for the CAM species was temporally opposite to that of C₃ species: for the CAM plant, soil water potential increased in shallow soils during the day when the plant was not transpiring and decreased at night when transpiration began. Because CAM plants transport water to shallow soils during the day when surrounding C₃ and C₄ plants transpire, CAM species that hydraulically lift water may influence water relations of surrounding species to a greater extent than hydraulically lifting C₃ or C₄ species. A strong, negative relationship between the percent sand in the study site soils at the 0.35 m soil depth and the frequency that hydraulic lift was observed at that depth suggests that the occurrence of hydraulic lift is negatively influenced by coarse-textured soils, perhaps due to less root–soil contact in sandy soils relative to finer-textured soils. Differences in soil texture among study sites may explain, in part, differences in the frequency that hydraulic lift was detected among these species. Further investigations are needed to elucidate species versus soil texture effects on hydraulic lift. This revised version was published online in June 2006 with corrections to the Cover Date.     

紫花苜蓿和斜茎黄耆水力提升作用及其对伴生植物的效应

为探讨紫花苜蓿(Medicago sativa)及斜茎黄耆(沙打旺, Astragalus laxmannii)与禾本科牧草混播后的水力提升现象, 揭示深、浅根性牧草的种间关系, 为混播草地的建植提供理论依据, 该研究开展了室外“上下盆”分根盆栽试验、采用土壤水分测定及“重水” (D₂O, 氘(D)含量>99.9%)标记法估算了苜蓿及斜茎黄耆分别与‘冬牧70’黑麦(Secale cereal ‘Dongmu 70’)不同混播比例(豆科:禾本科分别为3:7、5:5、7:3)条件下水力提升的发生情况及其对伴生牧草生长生理性状的影响。结果表明: ‘冬牧70’黑麦与斜茎黄耆混播后的产量显著高于其与紫花苜蓿混播后的产量, 同一种禾豆牧草混播组合不同混播比例中, 以AC2 (紫花苜蓿:‘冬牧70’黑麦为5:5)和BC3 (斜茎黄耆:‘冬牧70’黑麦为7:3)混播组合的总产量最高。不同单混播组合的单株整个生育期内日均提水量存在显著差异, 两种豆科牧草在混播时日均提水量均高于单播时, 斜茎黄耆单混播时的日均提水量显著高于紫花苜蓿, BC2组合(斜茎黄耆:‘冬牧70’黑麦为5:5)的日均提水量高于其他混播组合。在用标记水处理下盆土壤后, 各组合上下盆土壤水氢稳定同位素比率(δD)值显著升高。不同禾豆牧草组合上盆土壤水δD及禾本科牧草茎秆水δD、整株碳同位素分辨率(Δ¹³C)和产量数据表明, 在斜茎黄耆与‘冬牧70’黑麦混播比例为3:7、紫花苜蓿与‘冬牧70’黑麦混播比例为5:5时, 禾本科牧草水分状况或产量好于其他混播比例。以上结果表明, 两种深浅根豆科牧草与浅根性禾本科牧草混播种植时发生了水力提升现象, 两种豆科牧草提升的水分可以被伴生的禾本科牧草所吸收利用。     

Hydraulic lift of Medicago sativa and Astragalus laxmannii and its effect on their neighborhood plants

为探讨紫花苜蓿(Medicago sativa)及斜茎黄耆(沙打旺, Astragalus laxmannii)与禾本科牧草混播后的水力提升现象, 揭示深、浅根性牧草的种间关系, 为混播草地的建植提供理论依据, 该研究开展了室外“上下盆”分根盆栽试验、采用土壤水分测定及“重水” (D₂O, 氘(D)含量>99.9%)标记法估算了苜蓿及斜茎黄耆分别与‘冬牧70’黑麦(Secale cereal ‘Dongmu 70’)不同混播比例(豆科:禾本科分别为3:7、5:5、7:3)条件下水力提升的发生情况及其对伴生牧草生长生理性状的影响。结果表明: ‘冬牧70’黑麦与斜茎黄耆混播后的产量显著高于其与紫花苜蓿混播后的产量, 同一种禾豆牧草混播组合不同混播比例中, 以AC2 (紫花苜蓿:‘冬牧70’黑麦为5:5)和BC3 (斜茎黄耆:‘冬牧70’黑麦为7:3)混播组合的总产量最高。不同单混播组合的单株整个生育期内日均提水量存在显著差异, 两种豆科牧草在混播时日均提水量均高于单播时, 斜茎黄耆单混播时的日均提水量显著高于紫花苜蓿, BC2组合(斜茎黄耆:‘冬牧70’黑麦为5:5)的日均提水量高于其他混播组合。在用标记水处理下盆土壤后, 各组合上下盆土壤水氢稳定同位素比率(δD)值显著升高。不同禾豆牧草组合上盆土壤水δD及禾本科牧草茎秆水δD、整株碳同位素分辨率(Δ¹³C)和产量数据表明, 在斜茎黄耆与‘冬牧70’黑麦混播比例为3:7、紫花苜蓿与‘冬牧70’黑麦混播比例为5:5时, 禾本科牧草水分状况或产量好于其他混播比例。以上结果表明, 两种深浅根豆科牧草与浅根性禾本科牧草混播种植时发生了水力提升现象, 两种豆科牧草提升的水分可以被伴生的禾本科牧草所吸收利用。     

Hydraulic lift in drought-tolerant and -susceptible maize hybrids

Hydraulic lift was investigated in a greenhouse study involving two drought-tolerant maize (Zea mays L.) hybrids (TAES176 and P3223) and a drought-susceptible hybrid (P3225) during the flowering stage. Root systems were grown in two soil compartments – a drier upper soil and a wetter deep soil. The plants were shaded for 3 h during the daytime. Soil volumetric water content (Ø_v) in the upper pots was measured with time domain reflectometry (TDR) before and after shading. An increase in Ø_v in the upper pot was detected with TDR in the drought-tolerant hybrids following 3 h of shading, but not in the drought-susceptible hybrid. Furthermore, water exuded from roots in the top soil layers was greater in the more drought-tolerant TAES176 than in P3223 (489 vs. 288 g per pot in 3 h, P<0.005). The sizable amount of water from hydraulic lift allowed TAES176 to reach a peak transpiration rate 27–42% higher than the drought-susceptible hybrid P3225 on the days when the evaporative demand was high. To our knowledge, this is the first experiment that reveals a significant surge of transpiration due to hydraulic lift following midday shading. Hydraulic lift also prevented soil moisture depletion in the upper pots with TAES176, but not with P3223 or P3225. Root characteristics may be responsible for differences in hydraulic lift of the three maize hybrids. There were 2.3–3.3-fold more primary roots in the deep moist soil in P3223 and TAES176 than in P3225 that may enable these hybrids to absorb and transport water at faster rates. Therefore, more water can be exuded into the upper drier soil when transpiration is suppressed by shading. Larger primary roots (20–28% larger diameter) and a higher root volume in the upper soil in TAES176 and P3223 than in P3225 may contribute to higher root hydraulic conductance and greater water efflux from the roots. The negligible hydraulic lift in P3225 may also relate to higher night-time transpiration of the hybrid. This report has documented, for the first time, the existence of genetic variations in hydraulic lift among maize hybrids and links between hydraulic lift and drought tolerance within maize plants. It appears that one of drought tolerance mechanisms in maize may lie in the extent of hydraulic lift.     

Does hydraulic lift exist in shallow-rooted species? A quantitative examination with a half-shrub Gutierrezia sarothrae

Hydraulic lift occurs in some deep-rooted shrub and herbaceous species. In this process, water taken up by deep roots from the moist subsoil is delivered to the drier topsoil where it is later reabsorbed by shallow roots. However, little is known about the existence of hydraulic lift in shallow-rooted xeric species. The objectives of this study were 1) to ascertain whether hydraulic lift exists in Gutierrezia sarothrae (broom snakeweed), a widespread North American desert species with a shallow root system, grown in pot and field conditions and 2) if it does, how much water can be transferred from the subsoil to the 30 cm topsoil during the night. Snakeweed seedlings were transplanted in buried pots allowing the deeper roots to grow into the subsoil 30 cm below the surface. Soil water content inside and outside of the pot was measured seasonally and diurnally with time domain reflectometry technique (TDR). An increase in water content was detected in the pot after the plant was covered for 3 h by an opaque plastic bag during the day, suggesting hydraulic lift from deeper depths and exudation of water into the drier topsoil. Root exudation was also observed on native range sites dominated by snakeweed. Water efflux in the pot was 271 g per plant per night. which was equivalent to 15.3% of the extrapolated, porometer-derived whole-plant daily transpiration. Hydraulic lift observed in Gutierrezia improved water uptake during the day when evaporative demand is high and less water is available in the topsoil. We concluded that hydraulic lift might help snakeweed to alleviate the effect of water stress.     

施肥对沙打旺根系提水及土壤养分活性的影响

采用上下桶分根法,通过下桶施肥研究施肥对沙打旺根系提水作用能力及上桶土壤养分活性的影响.结果发现：沙打旺根系提水量随施肥量的增加而增加;在上桶不浇水的情况下,高肥处理组上桶伴生的浅根植物早熟禾在干旱胁迫时间较短时较对照组生长正常;根系提水量最大时,高肥和低肥处理的上桶土壤呼吸速率分别比对照增加14.9%和51.4%,有机质含量分别下降17.8%、19.6%,速效磷分别增加13.9%、33.2%,速效钾分别增加20.4%和22.8%.研究表明,施肥促进了沙打旺根系的生长发育,增加了下桶根系吸水和上桶释水量,有效地缓解了上桶土壤的旱情,显著提高了上桶土壤养分的活化程度和有效养分含量.