麻疯树不同种源的结实性差异与初期选择

采用随机完全区组设计对5年生麻疯树Jatropha curcas种源林进行结实性调查。结果表明,不同种源麻疯树单株产种量有不同程度的差异,云南元阳种源最高,达218.96 g,四川盐边种源最低,仅为48.42 g。不同种源麻疯树种子平均含油率也有所不同,广西隆林种源最高,达42.80%,贵州望谟种源最低,为37.23%。单株产种量与种源地纬度、年均气温显著相关,而与种源地无霜期极显著相关,其中与纬度为负相关,与年均气温、无霜期为正相关,说明纬度较低、气温较高和无霜期较长的种源在福建平和县的单株产种量高。而种子平均含油率与各地理气象因子之间没有显著相关性。根据单株产种量和种子平均含油率聚类分析,分别将9个种源分成优、良、中、差4个不同的类别,综合来看,云南东南部和广西西北部可能是麻疯树的优良种源区,该区域内的5个种源,单株产种量达147.43 g,种子平均含油率达41.07%。     

不同种源黄连木种子形态特征及脂肪油品质的差异性分析

对10个种源黄连木(Pistacia chinensis Bunge)种子的形态特征、果实含油率、籽油的理化性质和脂肪酸成分及其相对含量进行了测定分析.结果表明,不同种源黄连木种子的形态特征有显著差异(P<0.05),黄连木种子的千粒莺29.22～39.90 g,种子长度4.47～5.17 mm,种子宽度4.15～4.92 mm,长宽比为1.02～1.13.不同种源黄连木果实各部分的含油率均有极显著差异(P<0.01),果实、果肉和种仁的平均含油率分别为29.61%～38.61%、40.38%～64.54%和44.81%～55.97%,以江西彭泽、陕西商洛和云南石林种源的黄连木果实含油率较高.不同种源黄连木籽油的理化性质差异极显著(P<0.01),各种源黄连木籽油的折射率为1.469 6～1.475 1、碘值为748～924 g·kg-1、酸值为9.7～79.7 mg·g-1、水分含量为0.12%～1.40%.从黄连木籽油中共检测出棕榈油酸、油酸、亚油酸、亚麻酸、棕榈酸、硬脂酸和花生酸等7种脂肪酸成分,其中不饱和脂肪酸的总相对含量高达73.97%～87.41%.综合分析结果显示,江西彭泽的黄连木种子大而饱满且含油率高,可作为生物柴油油料资源的优良种源;云南石林、安徽滁州和陕西商洛的黄连木籽油的不饱和脂肪酸含量较高,可作为食用油原料资源的适合种源.     

香椿优树子代早期生长差异分析及初步选择

来自12个种源的70个香椿(Toona sinensis)优树子代在福建省永春县和华安县进行造林测定试验,调查2年生香椿优树子代测定林生长情况。结果表明,华安2年生香椿优树子代树高1.10～2.80 m,地径1.24～3.72 cm,永春2年生香椿优树子代树高0.91～2.71 m,地径1.18～3.68 cm,华安和永春两个试验点内不同香椿家系的树高和地径差异达到极显著水平(P<0.01)。华安试验点树高和地径的变异系数分别为20.22%和23.68%,初步选出6个早期生长表现优秀的家系,平均树高和地径分别为2.55 m和3.44 cm,平均遗传增益分别为23.70%和30.16%;永春试验点树高和地径的变异系数分别为26.44%和26.48%,初步选出19个早期生长表现优秀的家系,平均树高和地径分别为2.52 m和3.34 cm,平均遗传增益分别为25.07%和24.96%。通过树高和地径的聚类分析与生长比较,70个参试家系可分为优、良、中、差和极差5个类别。综合2个试验点生长表现,初步认定4号、23号、53号和65号等4个家系为优良家系。     

膏桐种子形态、粗脂肪含量与环境因子关系

对云南省两个不同地区膏桐（Jatropha curcas）种子形态特征,粗脂肪含量与环境因子关系开展研究,结果表明：湿热环境的景洪较干热环境的元谋膏桐种子成熟散布期提前,形态特征也优于元谋膏桐种子（P〈0．01）;土壤有机质是影响膏桐种子粗脂肪积累最重要的因子,对膏桐种子粗脂肪积累起显著正效应;干旱胁迫也是影响膏桐种子粗脂肪积累的一个重要的限制因子;景洪膏桐种子粗脂肪含量、含水量较元谋膏桐种子更高,但粗脂肪含量与含水量比率较低（P〈0．01）;具有较高粗脂肪含量的膏桐种子与其含水量的比率可能是植物对干旱胁迫适应的一种机制,其对物种的适应有着重要的生态学意义。     

梭梭不同种源间种子性状和幼苗生长性状与地理和气候因子的关系

对6个种源区梭梭[Haloxylon ammodendron(C.A.Mey.)Bunge]的种子性状和幼苗生长性状进行比较,并对这些性状与地理气候因子的相关性进行了分析,通过聚类分析方法对不同种源进行了评价.结果显示,不同种源间梭梭种子性状和幼苗生长性状存在显著差异,种子的果翅长度、种子千粒重、单株种子质量和种子发芽率的变化范围分别为5.13～7.14 mm、2.21～3.75 g、2.49～53.17 g和24.45%～75.00%,幼苗株高、新生枝长度、幼苗地径和幼苗成活率的变化范围分别为16.67～56.67 cm、14.33～29.34 cm、4.04～8.06 mm和42.56%～84.45%.不同种源梭梭的种子及幼苗生长性状与地理分布有关;单株种子质量、种子发芽率、幼苗株高和幼苗成活率与经度极显著正相关,果翅长度、种子千粒重和幼苗株高与纬度极显著负相关,海拔仪与果翅长度有显著相关关系;单株种子质量、种子发芽率和幼苗成活率的直接影响因子为经度,果翅长度、种子千粒重和新生枝长度的直接影响因子为纬度.气候因子与种子性状紧密相关,而与幼苗生长性状的相关性较差,仅幼苗成活率与1月气温和相对湿度存在极显著相关性;1月气温对果翅长度、单株种子质量、种子发芽率、幼苗株高和新牛枝长度的直接作用最大;年降雨量对地径的直接作用最大,相对湿度对幼苗成活率的直接作用最强.通过聚类分析将6个梭梭种源分为3类,其中内蒙古磴口种源为优良梭梭种源,新疆乌苏种源为较差种源.     

不同种源麻栎生长性状的地理变异

本研究在江西永丰、浙江开化和安徽滁州3个试验点,以32个种源的麻栎试验林为对象,分析了不同种源间林木生长变异、主要经济性状(地上单株生物量)随林龄的动态变化,并基于AMMI模型进行生长性状稳定性分析和优良种源选择。结果表明: 3个试验点麻栎不同种源间的树高、胸(地)径和地上单株生物量均具有显著差异。麻栎地上单株生物量受地点、种源、种源×地点交互作用的显著影响,其中地点对生长变异影响最大,其次为种源和种源×地点。不同地点麻栎苗期(1～3年生)和幼林期(4～11年生)优良种源的选择结果具有较大差异。根据第11年地上单株生物量分别筛选了在当地表现较好的种源,江西永丰试验点7个优良种源,高出试验点均值15.6%～57.8%;浙江开化试验点7个优良种源,高出试验点均值19.2%～45.2%;安徽滁州试验点8个优良种源,高出试验点均值24.9%～63.3%。综合生长量和稳定性表现,筛选出4个适于3个地理区域短轮伐期炭用林培育的优良种源,这些种源地上单株生物量均值为36.55 kg,稳定性参数均值为0.97。     

不同种源木姜叶柯种子生物学性状变异及质量特征研究

为探讨不同种源木姜叶柯种子生物学性状变异规律和质量特征,该文以8个省份10个种源为对象,测定了种子4个生物学性状、4个营养成分及3个质量性状数值,开展了11个种子特征参数的相关性及聚类分析。结果表明:(1)种子单粒重、种子长、种子数/种序、种序长均值依次为1.82 g、14.57 mm、16.43个、11.78 cm,不同种源种子 4个生物学性状变异均达到极显著水平。(2)种子蛋白质、脂肪、还原糖和淀粉均值分别为4.75 g/100 g、0.97 g/100 g、1.13%、74.23 g/100 g,淀粉在4个营养成分指标中差异最小。(3)种子百粒重、含水率和生活力均值依次为172.92 g、42.05%、53.00%,不同种源种子3个质量性状差异较大。(4)种子4个生物学性状与淀粉、蛋白质分别正向、负向相关,种子长与脂肪及还原性总糖正相关。(5)种子生物学性状与生境因子相关性复杂,种序长与无霜期极显著相关,相关系数达到0.832,与海拔显著负相关,相关系数达到-0.698,随纬度递增种子品质略变差。(6)种子聚类为第Ⅰ类短种序高营养成分型,第Ⅱ类长种序高生活力型,第Ⅲ类种子繁多高淀粉型等3类,聚类不呈现地理效应。综上所述,不同种源种子生物学性状和质量变异丰富,说明不同种源在子代分化已有遗传基础,种源筛选还需结合田间试验。     

米老排种源家系生长性状变异分析及早期选择

为分析米老排生长性状在种源和家系间的变异规律,筛选出速生的米老排优良种源和家系。以来自8个米老排地理种源的116个家系为研究对象,对米老排生长性状进行种源间和家系间遗传变异分析和育种值综合评分。结果表明：不同米老排种源间和家系间生长性状的差异均达到极显著水平。生长量最高的GXPX种源的平均树高、胸径和单株材积分别为9.50 m、13.40 cm、0.079 9 m³,是最差种源GXFC的1.28、1.42和2.30倍;生长最快家系是PX01,其平均树高、胸径和单株材积分别为9.86 m、15.31 cm和0.101 6 m³,其株材积是最差家系FC01的4.01倍,是家系群体均值的1.94倍。通过单性状选择对种源进行选择,初步选出2个优良种源,其树高、胸径和单株材积的预期遗传增益分别达到8.87%、11.79%和34.70%;运用育种值综合评分法对家系进行选择,初步选出12个优良家系,其树高、胸径树高和材积的预期遗传增益分别达到11.57%、17.35%和52.06%。GXPX和GXLZ 2个种源,PX01、LZ03、PX02、DB08、PX10、PX04、PX09、DB07、DB16、LZ05、JX16和PX05等12个家系是选出的综合生长表现最好的优良种源和家系,可作为米老排良种材料进行申报并推广。     

喀斯特地区珍贵树种黄枝油杉的种子萌发特性

黄枝油杉为中亚热带喀斯特地区珍贵树种,该物种分布范围狭窄,野生种群幼苗数量少,严重限制了其自然更新。为探求该物种濒危的原因,同时为其保护和利用提供参考,该文对黄枝油杉的种实性状进行了测定,并研究了温度、光照、土壤含水量、基质、贮藏温度和时间、不同地理种源等因素对种子萌发的影响。结果表明:(1)黄枝油杉球果平均结种率为7.45%±6.54%,种子有较长种翅[(2.27±0.32)cm],种子平均长度为(1.55±0.15)cm(不含种翅),平均宽度为(0.62±0.05)cm,平均厚度为(0.46±0.04)cm,平均千粒重为(214.81±14.76)g,风干种子平均含水量为15.28%±1.66%。(2)黄枝油杉种子萌发的适宜温度为25 ℃,在20 ℃和30 ℃下萌发率显著降低(P<0.05); 种子萌发不需要光照,但周期性光照条件下的萌发率显著高于持续光照和持续黑暗条件(P<0.05); 种子在土壤含水量为10%～30%条件下均能萌发,且能耐一定程度的干旱; 适宜萌发基质为质地疏松、透气性好的泥炭土和珍珠岩; 种子不耐贮藏,采集后应及时播种; 3个不同地理种源中以桂林恭城县三江乡种群种子萌发率最高。黄枝油杉球果结种率较低,种子萌发对温度要求严格,且种子易失去活力,这可能与其濒危有很大关系。     

不同种源麻栎种子形态特征和营养成分含量的差异及聚类分析

以27个种源的麻栎(Quercus acutissima Carr.)种子为实验材料,对不同种源间麻栎种子的形态特征和营养成分含量的筹异性进行分析比较.结果表明,不同种源间麻栎种子的长度、宽度和种子百粒重以及可溶性糖含量、淀粉含量和蛋白质含量差异极显著.麻栎种子的长度和宽度的变化幅度分别为1.69～2.26 cm和1.06～2.50 cm;种子百粒重的变化幅度为83.55～637.38 g;种子可溶性糖含量、淀粉含量和蛋白质含量的变化幅度分别为0.051～0.105 mg·g-1、0.278%～0.471%和21.502～34.696 mg·g-1.麻栎种子百粒重与种子的长度、宽度及可溶性糖含量间显著正相关,种子的长度与可溶性糖含量也显著正相关.主成分分析结果显示,影响麻栎种子品质的主要性状是种子的长度、宽度及种子百粒重.通过聚类分析,将27个麻栎种源划分为3组,其中第1组包括江苏下蜀、安徽太湖、安徽黄山、安徽休宁、安徽滁州、安徽潜山、浙江开化、浙江富阳和山东蒙阴等9个种源,种子品质较好,为优良种源.     

Estimates of broad-sense heritability for seed yield and yield components of safflower (Carthamus tinctorius L.)

This study was carried out to estimate the broad-sense heritability for seed yield and some yield components of safflower (Carthamus tinctorius L.) cultivars. The experimental design was a randomized complete block design with three replications in the 2004 growing season in the Middle Black Sea Region conditions of Turkey. Three safflower cultivars (5-154, Din?er and Yenice) were grown at five locations (Bafra, Ladik, Suluova, Gümü?hacik?y and Osmancik). The heritability for seed yield, plant height, first branch height, number of branch, head diameter, number of seed per head, 1000-seed weight and oil content were estimates as 35%, 93%, 99%, 45%, 21%, 69%, 81% and 59%, respectively. It was found that first branch height was the least affected trait over environments and followed plant height, thousand seed weight and number of seed per head. On the other hand, head diameter, seed yield, number of branch and oil content were the most affected traits versus environmental conditions. The first branch height, plant height and 1000-seed weight could be used to succeed in selection in early generation.     

孑遗树种钟萼木幼树生长特性探讨

研究了5 年生钟萼木幼树株高、地径连年生长、侧枝分生特性。结果表明,调查群体5 年生株高、地径平均值、最大值与最小值分别为2.0 m、3.4 m、0.5 m 和3.2 cm、9.5 cm、0.5 cm;群体幼树株高、地径生长分布遵循正态分布;幼树群体的株高、地径生长在早期表现显著的遗传分化。1～5 年生幼树的株高、地径年生长量表现为：株高在前3 年表现较低生长量,第4、5 年明显加快;地径在第1 年生长量占比较大。幼树株高小于2.0 m 的个体未发现分生侧枝,冠幅小且高生长较缓慢。     

塔里木河下游胡杨林胸径结构及林木分布特征

采用“面”上宏观调查与“点”上典型研究相结合, 集中对塔里木河下游阿拉干断面100 hm2的胡杨(Populus euphratica)林木分布与胸径结构进行了调查。结果发现, 在距河道0-20 m的范围内, 胸径为0-4 cm的幼龄胡杨占最多, 达到13.24%。以后随着离河道距离的增加, 幼龄胡杨所占比例逐渐减小。胸径分布范围简单, 胸径为16-36 cm的林木株数在胡杨林中所占的比例最多。另外, 随着离河道距离的增加, 胸径在48 cm以上的过熟林和衰老林的比例逐渐增多。距河道0-200 m的范围内, 胡杨分布占整个胡杨林的80%以上。其中以疏失度为0-50%的长势较好的胡杨为主。在200-400 m的范围内, 疏失度为50%-75%的长势较差的过熟林和衰老林的比例开始增多。距河道400 m以上, 胡杨密度开始急剧下降, 胡杨株数所占的比例几乎下降到5%以下。     

塔里木河下游胡杨林胸径结构及林木分布特征

采用“面”上宏观调查与“点”上典型研究相结合,集中对塔里木河下游阿拉干断面100hm^2的胡杨（Populus euphratica）林木分布与胸径结构进行了调查。结果发现,在距河道0—20m的范围内,胸径为0—4cm的幼龄胡杨占最多,达到13．24％。以后随着离河道距离的增加,幼龄胡杨所占比例逐渐减小。胸径分布范围简单,胸径为16—36cm的林木株数在胡杨林中所占的比例最多。另外,随着离河道距离的增加,胸径在48cm以上的过熟林和衰老林的比例逐渐增多。距河道0—200m的范围内,胡杨分布占整个胡杨林的80％以上。其中以疏失度为0—50％的长势较好的胡杨为主。在200—400m的范围内,疏失度为50％-75％的长势较差的过熟林和衰老林的比例开始增多。距河道400m以上,胡杨密度开始急剧下降,胡杨株数所占的比例几乎下降到5％以下。     

How do Araucaria angustifolia trees grow in overstocked stands?

The objective of this study was to evaluate growth along the stem of Araucaria angustifolia (Bertol.) Kuntze trees competing in overstocked stands, in order to identify periods when growth and trunk shape are differentiated during the trees' lifespan. The research was carried out in a planted forest of Araucaria angustifolia established in 1946 in the Açungui National Forest in Campo Largo, Paraná, Brazil, when these trees were 65 years old. One thinning was recorded, at some time between 1970 and 1980. Forty-six trees were selected and divided into three development classes (DC) at 65 years of age; these classes considered diameter at 1.30 m (breast height, dbh) with a range of 20 cm (from 10 cm to 70 cm). In addition to dbh, total tree height, and crown height and diameter were measured in the field. From each tree, 14 disks were removed to analyze growth rings and confirm the age of the stand. Some trees in the smallest DC (10 ≤ dbh < 30 cm) were the product of natural regeneration (younger trees that grew after the initial planting). In 63% of the trees, at least one growth ring was missing at breast height. Missing rings at breast height were more common in trees with smaller dbh and crown diameters. The need for more growing space was observed at different periods during the studied lifespan of the trees from three DCs. It resulted in changes in stems shape from conical to cylindrical. Different growth patterns could be observed during the lives of some trees as they outgrew their competition.     

四川理县杂谷脑干旱河谷岷江柏造林恢复效果评价

在岷江干旱河谷杂古脑河流域,选择岷江柏(Cupressus chengiana)5个不同年份的造林地,调查了岷江柏的生长情况、植物群落特征与土壤理化性质,总体评价干旱河谷乡土树种的造林成效及造林后的生态效果。结果表明:不同年份造林地岷江柏幼树生长状况良好,2003年造林地生长最好,基径、树高和冠径分别达到4.39cm、4.17m和1.01m,当年生长量超过43cm;2001年和2005年造林地次之,基径为4.19cm和4.52cm,冠径为0.55m和0.61m,当年生长量37cm左右,树高为2.50和2.17m;2007年和2009年造林地由于幼树生长时间较短,其基径、树高和冠径都较小,但当年生长量也都超过20cm。不同年份造林地的植被覆盖度变化相对复杂,除2001年造林地外,灌木层盖度随造林时间的增加而逐渐降低;草本层盖度变化较小,2005造林地最高,其他年份造林地没有显著差异。同时,不同年份造林地的群落结构都比较单一,随造林时间的增长,群落物种数量反而降低。在5个不同年份造林地,土壤pH、有机质和养分含量差异相对较小,土壤含水量尽管存在较大差异,但没有明显的变化趋势。综合分析认为,在杂谷脑干旱河谷中山区岷江柏作为造林树种具有一定的生长优势,但造林地的植被和土壤并没有得到改善,需要更加长期的观测评估。     

Genetic associations, variability and diversity in seed characters, growth, reproductive phenology and yield in Jatropha curcas (L.) accessions

A thorough and extensive wild germplasm exploration survey was undertaken and 32 high yielding candidate plus trees (CPTs) of Jatropha curcas from different locations from a latitudinal and longitudinal spread between 12°41′ and 22°′E longitude and 77° and 84°40′N latitude covering 11 locations in an area spread of 150,000 km² was collected for evaluating genetic association, and variability in seed and growth characters. Significant trait differences were observed in all the seed characters viz., seed morphology and oil content as were observed in growth characters viz., plant height, and female to male flower ratio and seed yield in the progeny trial. Broad sense heritability was high in general and exceeded 80% for all the seed traits studied. Female to male flower ratio showed near to 100% heritability followed by yield (83.61) and plant height (87.73). The path analysis revealed that female to male flower ratio had highest positive direct relationship with seed yield (0.789), followed by number of branches (0.612) and number of days from fruiting to maturity (0.431). Negative indirect effects were seen in number of days from flowering to fruiting which indirectly and negatively influenced yield through plant height and number of branches. Hierarchical clustering by Ward’s minimum variance cluster analysis showed phylogeographic patterns of genetic diversity. K-means clustering revealed that trees from different geographic regions were grouped together in a cluster and as were trees from the same geographical area placed in different clusters suggesting that geographical diversity did not go hand in hand with genetic diversity. In addition clustering identified promising accession with favourable traits for future establishment of elite seedling seed orchard and clonal seed orchard for varietal and hybridization programmes. For Genetical statistics please contact Arun K. Shanker (e-mail: arunshank@gmail.com).     

Genetic evaluation of Jatropha curcas: an important oilseed for biodiesel production

Jatropha curcas, internationally and locally known, respectively, as physic nut and pinh?o manso, is a highly promising species for biodiesel production in Brazil and other countries in the tropics. It is rustic, grows in warm regions and is easily cultivated. These characteristics and high-quality oil yields from the seeds have made this plant a priority for biodiesel programs in Brazil. Consequently, this species merits genetic investigations aimed at improving yields. Some studies have detected genetic variability in accessions in Africa and Asia. We have made the first genetic evaluation of J. curcas collected from Brazil. Our objective was to quantify genetic diversity and to estimate genetic parameters for growth and production traits and seed oil content. We evaluated 75 J. curcas progenies collected from Brazil and three from Cambodia. The mean oil content in the seeds was 31%, ranging from 16 to 45%. No genetic correlation between growth traits and seed oil content was found. However, high coefficients of genetic variation were found for plant height, number of branches, height of branches, and stem diameter. The highest individual narrow-sense heritabilities were found for leaf length (0.35) and width (0.34), stem diameter (0.24) and height of branches (0.21). We used a clustering algorithm to genetically identify the closest and most distant progenies, to assist in the development of new cultivars. Geographical diversity did not necessarily represent the genetic diversity among the accessions collected. These results are important for the continuity of breeding programs, aimed at obtaining cultivars with high grain yield and high oil content in seeds.     

Tree shape plasticity in relation to crown exposure

Trees outside closed forest stands differ in the relation between stem diameter, height and crown volume from trees that grew with neighbours close by. Whether this plasticity in tree shape varies between species in relation to their light requirement is unknown. We purposefully sampled 528 trees ranging 5–100?cm diameter at breast height growing in a range of light conditions. Across ten broad-leaved species observed in Sumatra or Kalimantan, a generic relationship was found between light exposure of the crown and a light-dependent a _l parameter that modifies the height–diameter allometric equation (H?=?a _l D ^b ) from those for closed stands. In our results, vertical stretching is well predicted by light availability. In fully open conditions, trees are on average 31% shorter for the same diameter than under (partial) shade. Most of the stretching response occurs in all species as soon as some degree of lateral shading occurs. The response, however, varies by species (8–44% reduction) in a way apparently unrelated to species’ successional status. Crown volume varied less than stem height in its relationship with stem diameter across all light conditions tested. The scaling of crown volume with stem diameter, however, differed markedly between tree species.