不同产地南方红豆杉各家系幼苗生长、光合生理与株高生长节律的差异分析

为充分了解不同产地南方红豆杉也Taxus wallichiana var. mairei ( Lemée et H. Lév.) L. K. Fu et Nan Li页各家系幼苗生长、光合生理及株高生长节律的差异,以产自江西分宜( FY)、浙江龙泉( LQ)、福建建瓯( JO)和福建明溪( MX)的20个家系的2年生容器苗为研究对象,对幼苗的株高和地径以及叶片的净光合速率和叶绿素含量进行比较,并对各家系的株高生长进行Logistic拟合回归分析以及拟合曲线参数和株高生长节律参数的计算和分析;在此基础上,分析了不同指标间的相关性并对供试的20个家系进行聚类分析。结果显示：不同产地间南方红豆杉的株高、地径、叶绿素含量和净光合速率均无显著差异,但这些指标在不同家系间均有极显著差异(P<0.01);各家系的株高、地径、净光合速率( Pn)以及叶绿素a( Chla)、叶绿素b( Chlb)和总叶绿素( Chl)含量的最大值较最小值分别高52.99%、29.63%、115.65%、39.81%、30.95%和37.24%。4个产地的株高生长均呈明显的“S型”曲线;各家系的最大生长速率( MGR)、线性生长速率( LGR)、线性生长总量( TLG)和线性生长持续时间( LGD)的最大值较最小值分别高60.00%、61.54%、63.73%和22.73%;从线性生长始期(t1)和线性生长终期(t2)来看,各家系的速生期为5月中旬或下旬至8月上旬。幼苗的株高与MGR、TLG、LGR、地径、Pn、Chlb和Chl等指标均极显著正相关,并与Chla显著正相关,而地径与MGR、TLG、LGR、Pn和Chlb等指标显著正相关,但株高和地径与LGD均无显著相关性。聚类分析结果表明：在欧氏距离10处,供试的20个家系被分成4个类型,其中,第Ⅳ类的6个家系的幼苗生长最佳且生长潜力最高。研究结果表明：不同产地南方红豆杉各家系的遗传变异丰富,且株高和地径生长主要受生长速率的影响;总体来看,家系LQ09、LQ11、FY21、FY26、MX12和MX18的幼苗生长潜力较高,可作为南方红豆杉的优良家系进行推广。     

光皮桦优树子代性状遗传变异及选择

在福建省选择101株光皮桦(Betula luminifera H. Winkl.)优树,利用其中55株优树的种子在福建省邵武卫闽林场开展子代测定分析. 结果表明, 光皮桦种内存在丰富的遗传变异, 优树子代间差异显著, 这些差异主要由遗传因素控制; 3 a生树高家系遗传力、单株遗传力分别为0.446和0.327, 胸径的家系遗传力和单株遗传力分别为 0.431和0.291;各生长性状与冠幅间存在紧密的相关性;以3a生树高为主要指标,从参试的家系中初步选出12个优良家系和31株优良个体,优良家系的树高和胸径的平均遗传增益分别为7.95%和11.87%;优良个体的树高和胸径的平均遗传增益分别高达26.60%和40.37%,选择效果非常明显.这些优良家系和个体可用作种子园建园材料或无性繁殖材料.     

21个甘蔗品种对螟虫抗性鉴定与评价

【目的】明确甘蔗品种对甘蔗螟虫的抗性,以期为抗虫品种推广应用和抗性基因发掘奠定基础。【方法】通过自然种群接虫方法,研究不同甘蔗品种苗期和生长中后期螟害水平。运用聚类分析方法,综合评价不同甘蔗品种对螟虫的抗性。【结果】不同甘蔗品种对螟虫危害造成的螟害枯心率、螟害株(节)率和株虫孔数等存在显著差异。21个甘蔗品种分为4个抗性等级。第1级1个品种(ROC10),螟害枯心率、螟害株(节)率、株虫孔数低;第2级包括4个品种(粤糖60号、柳城05-136、桂糖29号、粤糖55号),表现为螟害枯心率低、螟害株(节)率中等、株虫孔数中等;第3级包括9个品种(福农38号、桂糖31号等),表现为螟害枯心率中等、螟害株(节)率中等、株虫孔数中等;第4级包括7个品种(福农39号、德蔗03-83等),表现为螟害枯心率、螟害株(节)率、株虫孔数高。【结论】甘蔗品种和生育期影响螟虫的发生,不同品种对甘蔗螟虫抗性水平存在差异。     

红豆树优树种子和幼苗性状的变异分析及优良家系的初选

以不同产地(包括江西资溪,浙江的龙泉和庆元,福建的泰宁、南平和柘荣及四川内江)的76株红豆树(Ormosia hosiei Hemsl.et E.H.Wilson)优树的种子为供试材料,采用随机区组设计进行大田育苗,对其种子性状以及各家系幼苗的生长性状、叶片性状、根系性状和苗高生长节律进行测量和计算,并进行了方差分析、遗传力估算和相关性分析;此外,对供试红豆树优树中的优良家系进行了初选。结果表明:红豆树优树间的种子性状和家系间的幼苗性状均存在显著(P0.05)或极显著(P0.01)差异。红豆树幼苗生长性状、叶片性状和根系性状的家系遗传力为0.479~0.854,显示家系遗传控制程度中等或较强。相关性分析结果显示:红豆树幼苗的苗高和地径与种厚、百粒质量均呈极显著正相关;地径与叶片性状和根系性状的表型相关系数和遗传相关系数均达到显著或极显著水平,而苗高仅与主根长和单株长度大于5 cm的一级侧根数呈显著或极显著正相关;苗高与其线性生长始期、最大线性生长速率、线性生长速率和线性生长总量总体上呈极显著正相关,而与其线型生长末期和线性生长期呈不显著相关。根据家系遗传力,选择苗高作为主要性状,同时兼顾地径,从76个优树家系中初选出19个优良家系,其中,63.2%的优良家系来自浙江龙泉,26.3%的优良家系来自福建柘荣,浙江龙泉12家系的苗高和地径均为最大,浙江龙泉11家系的苗高和浙江龙泉19家系的地径次之。此外,最大叶片的长度和宽度的家系遗传力较高,且与地径呈显著或极显著正相关,可作为红豆树优良家系初选的辅助指标。研究结果显示:苗高、地径和叶片大小可用于初步筛选红豆树优良家系,且初选的优良家系可作为红豆树育种和无性繁殖材料。     

白桦杂交子代家系生长变异及稳定性分析

在幼龄林时期开展早期稳定性选择研究,为各造林地点及环境条件相似的毗邻地区选择优树,是林木遗传改良的重要环节之一。本文以21个白桦家系为材料,分别在庆安、尚志、辉南、丹东等4个试验点营建子代测定林,对2年生白桦树高和地径等性状进行多地点联合分析,结果表明：树高与地径性状在各地点间和各家系间以及家系与地点的交互作用上均达到差异极显著水平（P＜0.01）。在庆安试验点生长较好的有：201、203等家系;在尚志试验点生长较好的有:203、206、201、312、316、205等家系;辉南试验点生长较好的有：203家系;在丹东试验点生长较好的有：325、203、310、204、201、316等家系。采用Tai模型对参试家系的地径性状进行稳定性评价,结果显示:203与201家系是生长表现优异、稳定性强的最优家系;309、308、205、316、302和206等6个家系生长表现较好,生长适应性较强,是较好家系;311家系受环境条件影响大,为敏感型家系;325家系生长表现在各点均不一致,为不稳定家系。研究结果不仅为白桦优良家系的评价选择提供理论依据,而且也为优良亲本选择提供参考。     

红松半同胞家系遗传变异分析及果材兼用优良家系选择

以临江林业局闹枝林场内48个红松半同胞家系为材料,连续3年对其生长性状进行测定分析。方差分析结果表明不同家系间各性状差异均达极显著水平（P<0.01）;家系间各指标表型变异系数变化范围为2.74%~51.39%;半同胞家系间各性状遗传力均超过0.97;48个半同胞家系树高、胸径和单株球果数量的一般配合力变化范围为（-1.82~1.70）、（-7.91~9.99）和（-14.85~15.15）;不同树龄树高间、胸径间的相关系数达极显著水平（0.993 < r < 0.999,0.995 < r < 0.998）;分别利用生长性状和结实性状对家系进行综合评价,以10%的入选率,初步选出5个生长性状优良的家系,入选家系树高和胸径平均值分别为8.02 m和21.95 cm,遗传增益分别为7.63%和46.29%。初步选出5个结实性状优良的家系,球果数量和千粒重平均值分别为30.26个和736.20 g,遗传增益分别为86.49%和1.46%。本研究中评价选出的优良家系可为红松良种登记提供材料,选择方法为其它果材兼用树种良种选育提供理论基础。     

5个黄颡鱼家系组幼鱼生长、体组成和消化酶活力的比较

选取滆湖、石臼湖和太湖野生黄颡鱼亲本,设计建立5个繁育家系组,分别为自交组Ⅰ(G♂×G♀)、Ⅱ(S♂×S♀)和Ⅲ(T♂×T♀),杂交组Ⅳ(G♂×S♀)和Ⅴ(S♂×T♀)。家系组苗种培育至70 d时,每个家系组取鱼600尾,设3个平行,开展养殖试验,试验时间60 d,试验结束时测量各家系组黄颡鱼体重,计算体重绝对增长率(AGRW)、增重率(WGR)、饲料系数(FCR)、存活率(SR)等,并测定胃肠道消化酶生化指标。试验表明:各家系组间AGRW、WGR、FCR及存活率指标均差异显著(p0.05)。家系组Ⅳ的AGRW和WGR最高,分别为0.126±0.005、316.11±15.67,与其母本群体自交繁育家系组Ⅱ比较,在两个指标上均差异显著(p0.05)。家系组Ⅳ胃、肠蛋白酶活力均显著高于其他各组(p0.05),各家系组淀粉酶活力、脂肪酶活力差异不显著(p0.05)。研究得出,家系组Ⅳ(G♂×S♀),在饲料蛋白利用方面优于其他各组,促进了饲料利用和鱼体生长速度的提高,具有较好的生长表型,是具有开发潜力的优势繁育组合。     

白刺不同自由授粉家系的生长变异性研究

反映甘肃民勤县白刺分布区生态变化特征信息的55个白刺自由授粉家系,一、二、三年生植株的生长均存在极显著差异,说明这些家系可能属于不同的遗传变异群体。白刺生长的家系间变异较大,且变异性有逐年增大的趋势;不同生长指标间的同一指标上下年度间的生长变异有很大相关性。家系内变异与家系的个体生长状态呈极显著的负相关,生长越好的家系,变异越小,且变异与母株果实和种子特征无关。研究结果为优良生长家系选择奠定了基础。     

小麦品种(系)对不同地理种群荻草谷网蚜的抗性

采用田间成株期自然感蚜法和室内苗期接虫法,鉴定12个小麦品种(系)对5个不同地区荻草谷网蚜Sitobion miscanthi(Takahashi)种群的抗性。结果表明,小麦品种(系)室内苗期的抗性表现与田间成株期基本一致;Amigo、KOK、北京837、铭贤169和红芒红对5个地理种群荻草谷网蚜的抗性表现相同,丰产3、中4无芒、JP①、晋麦31、L1、885479-2和小白冬麦对5个地理种群荻草谷网蚜种群的抗性表现则存在差异。研究表明我国荻草谷网蚜对抗蚜作物品种具有致害性分化。     

顶果木优良家系和优良单株的选择研究

以广西壮族自治区范围内顶果木17个家系的实生苗为材料,探讨了顶果木优良家系和优良单株苗期选择的一些关键问题。结果表明:(1)不同家系间的苗高、地径生长量存在极显著差异。(2)通过苗高、地径两指标综合选择,选出苗期生长较快的优良家系5个,入选率为29.41%。(3)采用标准差选择法,选出155株超级苗,入选率为17.2%。     

Chicken intestine microbiota following the administration of lupulone, a hop-based antimicrobial

The use of antibiotic growth promotants in poultry rearing is a public health concern due to antibiotic resistance in bacteria and the harborage of resistance genes. Lupulone, a hop β-acid from Humulus lupulus, has been considered as a potential feed additive growth promotant. Here, the effect of lupulone was evaluated for its effect on the microbiota of the chicken intestine. The intestinal microbiota of broilers was quantified after the addition of 125 mg L(-1) lupulone to water and challenge with Clostridium perfringens. Microbial DNA was extracted from the broiler midgut and cecal sections and bacterial groups were quantified using real-time PCR. The predominant cecal bacterial groups were Clostridium leptum subgroup 16S rRNA gene Cluster IV, Clostridium coccoides subgroup 16S rRNA gene Clusters XIVa and XIVb and Bacteroides, whereas Lactobacillus, the Enterobacteriaceae family and Enterococcus dominated the midgut. Lupulone at 125 mg L(-1) significantly decreased the C. perfringens subgroup 16S rRNA gene Cluster I, which contains several pathogenic species, in both the midgut and the cecum and Lactobacillus in the midgut. No significant changes were noted in the overall microbiota for the cecum or the midgut. Lupulone warrants further evaluation as a botanical agent to mitigate C. perfringens overgrowth in antibiotic-free reared poultry.     

Characterising the effects of high ammonia emission on the growth of Norway spruce

This paper studies the effects of high ammonia emissions and nitrogen deposition on tree growth. Wood cores of 125 Norway spruces were analysed along a transect (800 m) from forest edge to forest interior. The forest edge was exposed to a strong ammonia emission source (poultry farm, less than 50 m). Atmospheric nitrogen bulk deposition, ammonia concentration, soil solution concentration, soil nutrient content, foliar N concentration and C/N ratio of the humus layer were measured at five plots along the transect. The tree growth increment of two clusters of trees close to the forest edge and forest interior was compared. The results indicate extremely high nitrogen load at the forest edge. All nitrogen variables show an `edge effect' with increasing values from forest interior to the forest edge. The growth of nitrogen-influenced spruce trees generally increases. Trees with excessive long-term nitrogen load appear to loose increment after a long-term nitrogen impact. The average gain of increment at the edge appears to be related to the amount of nitrogen emission.     

基于生态敏感性和生态系统服务价值的昌黎县生态廊道构建

生态廊道的作用在于提供生物迁徙的路径、促进不同栖息地之间的物种交流.廊道的构建能够减轻因城市化速度加快导致景观破碎化带来的危害,对生物多样性的保护具有十分重要的意义.本文以昌黎县为研究区,以2015年土地利用现状为基础,采用生态敏感性评价和生态系统服务价值分析的综合结果确定生态源地,然后基于最小累积阻力模型(MCR)和最小成本路径方法生成潜在廊道,根据重力模型对关键廊道进行识别,最终得到研究区包括4条重要廊道和2条一般廊道在内的生态廊道体系,旨在促进昌黎县生态廊道建设工程的科学实施和保护生物多样性.结果表明:研究区生态敏感性总体一般,生态系统服务价值总体较差,两者均呈现出四周高于中间的特点.生态源地主要分布在北部碣石山风景区、东部滨海国有林场和西部水源保护地这3个区域,与研究区生态环境建设与保护规划(2011-2030年)确定的自然保护区高度吻合.研究区生态廊道总长112.66 km,其中,重要廊道47.61 km,一般廊道65.05 km,廊道的最佳宽度范围为30～60 m,生态廊道与生态源地大致构成了一个环形闭合区域,能够有效促进生物物种的迁徙和物质能量的交流.     

亚热带山地森林附生地衣的移植生长及其对环境变化的响应

本研究选取云南哀牢山亚热带森林系统6种常见的附生大型地衣进行为期2年的移植实验,分析其在原生林林外、林缘以及林内3种生境下的生物量增长速率和健康率等的差异,并探讨其生长对环境因子变化的响应。结果显示,网肺衣Lobaria retigera和平滑牛皮叶Sticta nylanderiana在林缘处生物量增长最快;而槽枝Sulcaria sulcata、多花松萝Usnea florida、皮革肾岛衣Nephromopsis pallescens、针芽肺衣Lobaria isidiophora 4种地衣则都是在林外光照更强、湿度更低的条件下生长得最好,林内最差。除网肺衣外,所有地衣的健康率均在林外较好,林缘次之,林内最差。非参数相关分析表明,6种地衣的生长速率和光照以及温度呈正相关,与大气湿度呈负相关;温度和光照是影响地衣生长最主要的生境因子。     

Butterfly diversity and silvicultural practice in lowland rainforests of Cameroon

Butterfly diversity and abundance were sampled across eight 1-ha silvicultural treatment plots in southern Cameroon. The plotsincluded a cleared and unplanted farm fallow, cleared and replanted forestplots, and uncleared forest plots. The replanted plots were line-planted withTerminalia ivorensis, but differed in the degree and methodof clearance. A total of 205 species of butterflies were collected over twodifferent seasons. Several sampling methods were used, including hand collecting andbaited canopy traps. Sites with the greatest degree of disturbance andlowest level of tree cover had the lowest number of individuals and species ofbutterflies. The farm fallow had substantially fewer individuals and species ofbutterflies than the other plots. The replanted plots were intermediate betweenthe farm fallow and uncleared forest in terms of abundance, richness andcomposition. With all three forms of multivariate analysis (Morisita similarityindex clustering, detrended correspondence analysis and two-way indicatorspecies analysis) largest differences were found between the farm fallow anduncleared forest plots. The butterfly fauna of the uncleared forest more closelyapproximated that of the manually cleared plot than that of the mechanicallycleared plot. We found that although, in general, young replanted forest plotsare a poor substitute for native forest, they do provide habitat for some forestspecies and that this may increase over time as the plots mature.     

南京城市森林干扰及恢复自动制图

使用1987—2011年Landsat TM/ETM⁺稠密时间序列数据,以南京市老山林场和紫金山森林为研究对象,通过Ledaps预处理系统生成地表反射率数据集,采用植被变化追踪模型(VCT)得到南京城市森林的干扰及恢复历史数据库产品,并对产品进行验证.结果表明： 空间一致性为65.4%～95.0%,VCT产品监测森林干扰具有较高的空间一致性.2个研究区的森林干扰和恢复随着时间变化波动明显,干扰变化规律相似,但森林恢复规律明显不同.紫金山的森林覆盖率小于老山林场,但总体上,老山林场的森林干扰率和恢复率大于紫金山.     

SPATIAL AND AGE DEPENDENT PATTERNS OF GROWTH IN NEW ENGLAND BLACK BIRCH

Ring width chronologies from 127 black birch trees in the northeastern United States were used to study age dependent and spatial patterns in growth. The trees sampled show no evidence for increasing stability of growth with age, as measured by the year-to-year variance and autocorrelation. Large scale spatial patterns were studied using trees sampled from five localities separated by distances of 40 km to 325 km. Cluster analysis based on the last 30 years of growth is able to assign a tree to its locality of origin with approximately 80% accuracy. However, the degree of correlation between these chronologies does not decline as a function of the distance of separation of the localities. Fine scale patterns were studied using chronologies from 46 birches lying within a 50-m x 60-m plot. Strong neighborhood effects could not be detected in the rate of growth, the variance of growth, or the between-tree correlation. Dry-site trees, however, were found to be growing significantly faster and with less variability than wet-site trees. The results suggest that very local factors are important determinants of growth and dominate the environmental structure perceived by mesic forest trees.     

Butterfly community recovery in degraded rainforest habitats in the Upper Guinean Forest Zone (Kakum forest, Ghana)

Successful regeneration of secondary tropical forest might be crucial in the conservation of rainforests, since large areas of primary forest have been destroyed or degraded. Animal communities might play an important role in restoration of biological diversity in these secondary habitats, since some groups have high mobility and capacity for dispersal. Fruit-feeding butterflies were trapped to measure differences between butterfly communities in primary rainforest and disturbed forest habitats of different stage of regeneration including clear-cut, abandoned farmland, newly planted forest and middle-aged secondary growth. 3465 specimens representing 114 species were identified from 56 traps operated for 36 days. Extremely high values of rarefied species richness were estimated in the clear-cut habitat, due to the high number of singletons and doubletons. This was caused by a gap-effect that allowed penetration of canopy and open area species after disturbance. The differences between butterfly communities were best demonstrated through ecological composition, richness and abundance of indicator groups and habitat similarity based on Jaccard’s similarity index. The results show a clear ability of butterfly communities in degraded forest habitats to regenerate in 50–60 years after clearance.     

Forest cover mediates genetic connectivity of northwestern cougars

Population structure, connectivity, and dispersal success of individuals can be challenging to demonstrate for solitary carnivores with low population densities. Though the cougar (Puma concolor) is widely distributed throughout North America and is capable of dispersing long distances, populations can be geographically structured and genetic isolation has been documented in some small populations. We described genetic structure and explored the relationship between landscape resistance and genetic variation in cougars in Washington and southern British Columbia using allele frequencies of 17 microsatellite loci for felids. We evaluated population structure of cougars using the Geneland clustering algorithm and spatial principal components analysis. We then used Circuitscape to estimate the landscape resistance between pairs of individuals based on rescaled GIS layers for forest canopy cover, elevation, human population density and highways. We quantified the effect of landscape resistance on genetic distance using multiple regression on distance matrices and boosted regression tree analysis. Cluster analysis identified four populations in the study area. Multiple regression on distance matrices and boosted regression tree models indicated that only forest canopy cover and geographic distance between individuals had an effect on genetic distance. The boundaries between genetic clusters largely corresponded with breaks in forest cover, showing agreement between population structure and genetic gradient analyses. Our data indicate that forest cover promotes gene flow for cougars in the Pacific Northwest, which provides insight managers can use to preserve or enhance genetic connectivity.