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1.
植物的抗旱性是植物在干旱环境下生存的基础,是植物适应不利环境的机制与策略。在黄土高原半干旱区3种主要草地类型(森林草原、典型草原和荒漠草原)的典型区域,选取4个具有明显地带性的本氏针茅(Stipa bungeana)种群,测定其若干抗旱性生理指标,分析其生理生化特性的差异及这些性状之间的相关性,并利用模糊数学中的隶属函数值法对这些指标及不同地理分布本氏针茅种群的抗旱性进行综合定量评价。结果表明:叶绿素和丙二醛能反映生境的干旱程度;保护酶活性在种群间的变化并不规律;渗透调节物质含量在同一种群内存在"互补"现象;Pearson相关分析发现多数指标间并不存在显著相关关系,且与生境的变化趋势不一致;利用UPGMA法对其构建的各种群间聚类关系图也不能反映种群间实际地理距离和生境的相似性;综合抗旱性强弱顺序为:内蒙古种群>甘肃种群>陕西种群>宁夏种群,总体趋势表现为水分条件越差抗旱性越强。 相似文献
2.
针对不同区域的鸭茅(Dactylis glmerata)对环境的适应性,选取天山北坡东段与西段鸭茅分布的典型区域,研究分析了鸭茅种群植株部分生理生化特征的差异以及这些性状之间的关联.结果表明:天山西段及东段野生鸭茅除叶片相对含水量、脯氨酸(Pro)含量及超氧化物歧化酶(SOD)活性差异不显著外,叶绿素含量、丙二醛(MDA)含量及过氧化物酶(POD)活性在种群间均成差异显著(P＜0.05);进一步分析表明,叶绿素含量、叶绿素a/b比值的大小与分布生境的海拔、年内降水量有关;MDA含量也反映出分布地段的生境差异性与当地降水量有很大关系a研究结果初步揭示了分布地段野生鸭茅居群在相异生境下适应环境的一些信息,可为该地区鸭茅种质资源的评价与新品种选育等提供部分参考数据. 相似文献
3.
在内蒙古锡林郭勒草原区选取5个克氏针茅分布的典型样地,并测定了这5个克氏针茅种群的若干抗旱生理指标.结果显示:(1)游离脯氨酸和可溶性糖含量在5个克氏针茅种群表现为中间低一两侧高的分布模式,而游离氨基酸则表现为中间高一两侧低的分布模式.(2)来源于生境条件最湿润的西乌珠穆沁旗种群克氏针茅的丙二醛含量最低,但来源于生境条件最干旱的苏尼特左旗种群的丙二醛含量并不是最高.(3)SOD、POD、CAT 三种保护酶活性在种群间的变化并无规律可循,但存阿巴嘎旗种群这三种酶活性都是最高的.(4)多数指标之间没有显著的相关关系,基于这些指标所得到的种群间的聚类关系不能反映克氏针茅所处生境相似性及种群间的地理距离. 相似文献
4.
植物种群化学计量内稳性特征反映植物种群在某一生态环境中的适应情况与生存策略,对于维持生态系统稳定性具有重要意义。以欧亚温带草原东缘生态样带上的大针茅植物种群为研究对象,采用单因素方差分析、回归分析与对应分析等方法,对大针茅叶片氮、磷含量和氮磷比的变化及大针茅叶片氮磷比与土壤全氮、全磷含量和氮磷比随着纬度梯度变化的相关性进行分析,探讨大针茅叶片氮磷化学计量内稳性。结果表明：(1)大针茅叶片氮含量、氮磷比与纬度梯度具有显著负相关关系(P<0.05),大针茅叶片磷含量与纬度梯度无显著关系;(2)大针茅叶片氮磷比受20～30 cm土层的全磷、10～20 cm土层的全氮和氮磷比影响较大,且存在明显的回归关系(P<0.15),中低纬度和高纬度的大针茅叶片氮磷比存在明显的分界;(3)大针茅叶片氮、磷和氮磷比的内稳性指数均属于绝对稳态型或弱稳态型,具有较强的内稳性。表明大针茅种群在欧亚温带草原东缘生态样带地区适应性较强,可以通过维持自身化学计量内稳性来适应土壤化学计量变化,在多变的环境中保持优势地位。 相似文献
5.
为了明确同一土壤类型不同地势天然草地主要牧草叶绿素含量与蛋白质含量的相关性,进一步准确反映草地的营养价值和载畜能力。测定了对赤峰市巴林左旗查干哈达苏木典型草原打草场的坡地、平地和洼地的羊草、大针茅、达乌里胡枝子3种主要牧草的叶绿素含量和蛋白质含量并进行了相关性分析。结果表明,平地羊草叶绿素含量与蛋白质含量最高,坡地和平地的大针茅叶绿素含量和蛋白质含量明显高于洼地;洼地的达乌里胡枝子叶绿素含量与蛋白质含量最高。同一土壤类型不同地势3种主要牧草中的蛋白质含量与叶绿素含量呈正相关,说明这3种牧草可以用叶绿素含量来估测其蛋白质含量。并且羊草生长在地势平坦的地方具有更高的营养价值;大针茅生长在坡地上具有较高营养价值;达乌里胡枝子生长在地势低洼的地方具有较高营养价值。 相似文献
6.
锡林郭勒草原克氏针茅抗旱生理变化的研究 总被引：10，自引：2，他引：8
为揭示不同生长时期、不同地区克氏针茅Stipa krylovii抗旱性,对内蒙古锡林郭勒草原5个地区克氏针茅的某些抗性生理指标:丙二醛(MDA)、超氧化物歧化酶(SOD)、过氧化物酶(POD)、脯氨酸(Pro)进行比较分析,结果表明:5月份(生长初期)克氏针茅MDA含量最高,POD、SOD活性最低;7月份(盛期)与9月份(末期)MDA含量降低,POD、SOD活性增加,而游离脯氨酸含量变化并不规律。综合分析表明,克氏针茅在分布区内,随着降水量的减少,游离Pro含量和保护酶活性增加,MDA减少,在生理方面表现出对环境较强的适应性。 相似文献
7.
植物功能性状是植物响应草地变化的主要指标,对于了解草地发展进程具有重要意义。本试验对牦牛、藏羊混合放牧（不同放牧方式）下对紫花针茅（Stipa purpurea）叶片元素含量（碳含量、氮含量、碳氮比）及种群表型性状指标（植株高度、单株重、叶厚、比叶面积）进行测定,旨在明确放牧方式对紫花针茅的影响。结果显示：不同放牧方式对紫花针茅碳含量、氮含量、碳氮比、叶厚无显著影响,对植株高度、单株重、比叶面积影响显著（P<0.05）,牦牛藏羊1∶4混牧处理下紫花针茅植株高度、单株重、比叶面积受放牧影响最显著（P<0.05）,与禁牧相比,分别降低了39.0%,59.70%,22.8%;相关性分析可知：植株高度、比叶面积、单株重存在极显著正相关关系（P<0.01）;单株重是紫花针茅响应放牧干扰的主要性状指标;综合分析可得牦牛藏羊1∶4混牧处理对紫花针茅功能性状影响最为显著。 相似文献
8.
内蒙古高原克氏针茅种群的生态分化 总被引：1，自引：1，他引：0
采用野外形态调查和DNA分子标记方法,对内蒙古高原7个不同地理分布的克氏针茅种群进行研究,结果表明:不同地理分布区克氏针茅种群的表型性状受环境影响改变程度的差异不同,其中营养枝高度、生殖枝高度、千粒重、颖果长、芒柱长具有随降水量递减而变小、变短的趋势;而颖果直径表现为随降水量的递减逐渐增加的趋势。随机扩增多态DNA(RAPD)分析表明,16个有效引物共扩增出129个位点,其中多态位点128个(99.22%)。AMOVA分析显示,克氏针茅种群64.95%的遗传变异发生在种群内,35.05%的遗传变异发生在种群间。种群遗传多样性与其所处生境的年均温呈显著相关关系(r=0.802,t=3.003t0.05=2.571)。聚类分析表明,7个种群一级聚类分为4个分支,有相似生态条件的种群具有优先聚类的趋势,种群间遗传距离与地理距离无明显的相关性。克氏针茅有较大的形态变化和丰富的遗传多样性,环境适应潜力大,可作为西部地区植被恢复及草地生态建设的首选植物之一。 相似文献
9.
引种花卉紫串扦插苗对高温胁迫的生理响应 总被引：1，自引：0，他引：1
以引种植物紫串扦插苗为试验材料,研究其在高温胁迫环境下形态结构和生理指标的变化,其目的是探明紫串对高温胁迫的生理响应及适应机制。结果显示,高温胁迫对紫串的形态特征产生了一定的影响,随着胁迫温度升高或胁迫时间延长,紫串受害指数均逐渐增大,持续高温胁迫可导致紫串植株萎蔫甚至死亡,解除胁迫后多数植株能够进行自我恢复;高温胁迫过程中紫串的大多数生理指标均呈一定的规律性变化,随着胁迫温度升高或胁迫时间延长,叶绿素和类胡萝卜素含量均明显减少,丙二醛和脯氨酸含量基本呈现微增-剧增-微减的趋势,SOD活性持续缓慢升高,CAT活性先缓慢上升而后急剧下降;35℃和40℃高温胁迫对紫串扦插苗生长影响较小,受害指数和大部分生理生化指标均与对照差异不显著,45℃高温胁迫1～2 d后紫串会产生一定的热伤害,但可以通过自我调节进行恢复,45℃高温胁迫3 d后只有45%的植株可通过自身调节继续存活,55%植株萎蔫甚至死亡;高温环境下紫串扦插苗受害指数与叶绿素、丙二醛﹑脯氨酸、SOD和CAT等生理指标间均具有显著相关性,可以作为紫串的耐热性鉴定指标。 相似文献
10.
不同退化梯度克氏针茅种群形态及等位酶的分析 总被引：6，自引：2，他引：4
通过对克氏针茅Stipa krylovil退化系列种群分析表明,形态变异随退化程度而异.营养枝和生殖枝长度随退化的加重变短,中、小株丛减少,生殖分配减少,生殖枝数量减少.重度退化种群,植株小型化明显.等位酶分析表明,多态位点的百分率均在100%;平均每个位点的等位基因数(A)是2.25,有效等位基因数(Ae)和遗传多样度指数(He)在种群内的分布规律是中度退化种群》重度退化种群》无退化种群》轻度退化种群,当放牧压力达到一个阈值时,种群的遗传多样性有增加的趋势.克氏针茅种群间的分化系数GsT为0.236 4,退化系列克氏针茅种群间出现一定的分化.克氏针茅退化种群,生产力衰退明显但遗传多样性并未丧失,反而形成了一个相对稳定的遗传结构适应环境(放牧)的压力. 相似文献
11.
不同生境小花山桃草自然种群表型变异与协变 总被引：1，自引：0，他引：1
小花山桃草自然种群的表型特征是其对自然生境适应的结果,不同生境种群间表型特征的比较可为揭示其表型变异产生的原因及变异规律提供重要线索。本研究以分布于不同生境的5个小花山桃草自然种群为研究对象,研究了16个表型性状的变化特点。研究结果表明,小花山桃草表型多样性较为丰富,表型性状的平均变异系数为36.30%。表型分化系数在26.85%~96.98%之间,平均为73.03%,表明种群间变异是小花山桃草表型变异的主要来源。不同性状对环境变化的反应不同,其中株高、茎粗、单株果数和比叶面积在种群内的差异不显著,而在种群间的差异达到极显著水平,表型分化系数达82%以上;节间距、叶宽、主根长、分枝数、果长和果宽在种群间和种群内的差异均达极显著水平;单果种子数和单果重在种群内和种群间的差异均不显著。株高、茎粗、叶长、叶宽、茎重、叶重、主根重和单株果数表现出一致的协变格局,生理功能性状之间的这种整合特性有助于小花山桃草适应多样的生境。聚类分析显示,5个种群可按生境条件的好坏分为两大类,进一步表明小花山桃草的表型特征受种群间环境条件(水、肥)强烈影响。绝大多数表型性状与生境因子存在显著或极显著的相关关系,但果实性状(包括果宽、单果重和单果种子数)与生境因子相关性低,进一步表明繁殖性状不易受环境条件影响。 相似文献
12.
撒坝猪乳头数遗传力及其与繁殖性能关系的研究 总被引：4，自引：0，他引：4
本研究对 4个世代共 577头撒坝猪的乳头数进行了分析 ,并用HARVEY程序对乳头数的遗传力进行了估计 ,同时利用 1 2 8头有繁殖性能记录的母猪资料对乳头数与繁殖性状的关系进行了分析。结果表明 ,各世代的乳头数存在着显著差异 ,且逐代均有显著提高 ;乳头数的遗传力为 0 .331 ;乳头数与总产仔数和活产仔数间遗传相关和表型相关均为负值 ,与初生窝重、2 0日窝重、断奶仔数和断奶窝重间则存在着正的遗传相关和表型相关 ;乳头数与所有繁殖性状的环境相关都较弱 ( -0 .0 0 2～ 0 .0 94 ) 相似文献
13.
McManus C Castanheira M Paiva SR Louvandini H Fioravanti MC Paludo GR Bianchini E Corrêa PS 《Tropical animal health and production》2011,43(3):623-630
Adaptability can be evaluated by the ability of an animal to adjust to environmental conditions and is especially important
in extreme weather conditions such as that found in tropical Brazil. A multivariate analysis using physical and physiological
traits in exotic (Nellore and Holstein) and naturalized (Junqueira, Curraleira, Mocho Nacional, Crioula Lageana, and Pantaneira)
cattle breeds was carried out in the Federal District of Brazil to test and determine which traits are important in the adaptation
of animal to heat stress as well as the ability of these traits and statistical techniques to separate the breeds studied.
Both physical and physiological traits were measured on three occasions and included body measurements, skin and hair thickness,
hair number and length, pigmentation, sweat gland area as well as heart and breathing rates, rectal temperature, sweating
rate, and blood parameters. The data underwent multivariate statistical analyses, including cluster, discriminate, and canonical
procedures. The tree diagram showed clear distances between the groups studied, and canonical analysis was able to separate
individuals in groups. Coat traits explained little variation in physiological parameters. The traits which had higher discriminatory
power included packed cell volume, shoulder height, mean corpuscular volume, body length, and heart girth. Morphological and
physiological traits were able to discriminate between the breeds tested, with blood and size traits being the most important.
More than 80% of animals of all breeds were correctly classified in their genetic group. 相似文献
14.
Innate immune traits differ between Meishan and Large White pigs 总被引：1，自引：0，他引：1
A panel of innate immune traits were compared between Meishan and Large White pigs. These pigs were of similar age and kept under the same environmental conditions to reduce non-genetically derived variation in immune traits. The animals were all apparently healthy and were not experimentally challenged with any pathogen during the study. The measures only required a small blood sample. Total white cell counts were similar between the pig breeds. However, the numbers of lymphocytes, neutrophils and monocytes differed significantly, with Meishans having higher neutrophil and monocyte counts and lower lymphocyte counts. Flow cytometric methods were used to determine quantitatively the characteristics and function of neutrophils and monocytes. Meishan neutrophils were smaller and less complex than Large White neutrophils, and phagocytosis of Escherichia coli and the ensuing oxidative burst was lower in Meishan neutrophils compared to Large White neutrophils. Monocyte phagocytosis of E. coli was significantly less than that of neutrophils in both breeds but the function of Meishan monocytes as measured by phagocytosis and tumour necrosis factor alpha (TNFalpha) release did not differ from that of Large White monocytes. Levels of acute phase proteins also differed between the breeds with a significantly higher proportion of Meishans having elevated serum amyloid A levels. However, Meishans had lower alpha(1)-acid glycoprotein levels than Large Whites and haptoglobin levels were similar. Such differences in innate immune traits may have implications in the resistance to infection by a broad range of pathogens and subsequent disease effects in these breeds. Further studies are warranted to investigate the genes underlying these traits. 相似文献
15.
羊草是我国重要优良牧草之一，广泛分布于欧亚草原，由于资源环境的多样性和自然选择的复杂性，羊草种群发生了丰富的表型变异。以不同地理来源的66份羊草为试验材料，采用同质园试验方法，研究了羊草种群间表型和繁殖相关性状的变异情况，用曲线拟合和偏最小二乘回归分析研究了变量性状对羊草根茎克隆无性繁殖的影响。主要结论如下：1）不同地理来源羊草的表型和繁殖性状存在显著差异，原生境条件对羊草表型和繁殖产生了深刻而长久的影响。2）羊草不同性状的变异程度有所不同，叶片性状的变异最小，根茎子株相关性状的变异大于空间扩展相关性状。3）线性函数可较好地描述羊草根茎克隆生长力与主要变量性状间的关系。4）表型性状茎长、株高、叶宽和叶片大小，分蘖能力相关性状母株分蘖增加倍数对羊草根茎克隆生长力的解释作用强。总之，叶片宽大、茎长和株高方面有优势、分蘖能力强的羊草的根茎克隆无性繁殖能力相应也强。 相似文献
16.
R. Roehe N.P. Shrestha W. Mekkawy E.M. Baxter P.W. Knap K.M. Smurthwaite S. Jarvis A.B. Lawrence S.A. Edwards 《Livestock Science》2009,121(2-3):173-181
Genetic parameters of piglet survival traits and birth weight were estimated on the first generation data of a selection experiment aimed at improving piglet survival using a multiple trait linear and threshold model. Data on 5293 piglets for survival at birth, at day one after birth and during the entire nursing period, as well as individual birth weight and litter size, were recorded in an outdoor production system. Genetic effects of piglet survival traits and birth weight were estimated based on threshold and Gaussian models, respectively, using a Bayesian approach. The statistical model included as fixed effects selection group, parity, gender, fostering, gestation length and month of farrowing and, alternatively, an adjustment for litter size. Direct genetic effects (i.e. the piglet's genetic potential) for piglet survival and birth weight were estimated separately, whereas maternal genetic and environmental effects could only be estimated for the given data structure in a combined litter effect. Posterior means of heritabilities for direct genetic effects of survival at birth, at first day after birth and the entire nursing period, as well as birth weight, were 0.08, 0.07, 0.08 and 0.20, respectively. Genetic correlations among survival traits were in the range of 0.29 to 0.40 and indicate that these traits were mainly attributable to different genetic effects. Genetic correlations between direct effects of survival traits and birth weight ranged between 0.18 and 0.23 and were reduced when weights of stillborn piglets were omitted in the analysis or the traits were adjusted for litter size. The magnitudes of direct genetic effects of survival traits are substantially higher than estimates in the literature, which may indicate that these traits have a higher genetic influence under outdoor conditions. The use of birth weight in the multiple trait estimation provided important information for the estimation of survival traits due to its favourable genetic correlations with survival, its high heritability and its high information content as a continuously measured trait. 相似文献
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灰绿藜形态性状与繁殖性状的异速关系 总被引：1，自引：0，他引：1
通过对不同光照强度、营养和萌发时间处理条件下灰绿藜的形态指标和繁殖指标的测定,本研究探讨了灰绿藜形态性状和繁殖性状之间的异速关系及其异速生长对环境变化的响应。结果表明:灰绿藜形态性状与繁殖性状之间存在显著的异速生长关系,随着灰绿藜个体大小的增大,单个枝条的大小增速更快,并且将更多的资源分配到灰绿藜的繁殖生长。但灰绿藜的花序密度与个体大小之间具有显著的权衡关系:灰绿藜越小,花序密度越高。光照处理引起植物的繁殖性状发生了变化,但是这些变化主要是由在光照梯度下的个体大小不同造成的,繁殖策略(异速生长)未发生改变。而营养及萌发时间处理对灰绿藜的形态性状与繁殖性状间的异速关系产生了影响。营养变化对不同性状间的异速关系无一致影响,而萌发时间则具有显著的影响,晚萌发的灰绿藜将更多的资源投入到繁殖生长。 相似文献
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1. The objective of the study was to explore the genetic architecture of blood oxygen saturation (SaO) (an indicator trait, negatively correlated with ascites susceptibility), body weight (Weight) and fleshing score (Flesh, a measure of breast conformation) for 4 meat-type chicken lines reared in commercial conditions. 2. Genetic components, including heritabilities and genetic correlations, were estimated by Restricted Maximum likelihood for these traits measured at 6 weeks of age. 3. Data were collected over eight generations of selection and pedigrees comprised in excess of 130,000 birds. 4. Univariate analyses were performed to allow model definition and to obtain starting values for trivariate analyses. The basic model included a random animal effect and, in further models explored, a maternal environmental effect or a genetic maternal effect or both were fitted. Models were compared using likelihood ratio tests. 5. Estimated heritabilities for SaO ranged from 0.1 to 0.2, and there was no evidence of genetic maternal effects for SaO. The environmental maternal component was significant for one of the populations only. Estimated heritabilities for both Weight and Flesh were between 0.2 and 0.4, and there was evidence of environmental and genetic maternal effects for these traits in all populations. 6. Genetic correlations between SaO and Weight and between SaO and Flesh were low and negative. This suggests that, in principle, genetic selection to simultaneously increase SaO, and therefore decrease ascites susceptibility, and WEight and Flesh could be performed using traditional (marker-free) selection methods. We discuss how a putative interaction between ascites and production traits could jeopardise the success of such methods. 相似文献