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1.
Drought is one of the crucial factors limiting plant growth and is expected to become even more limiting in many regions as the effects of climate change increase. Knowledge of genetic adaptation to environmental factors can help develop strategies for successful reforestation in arid terrain. In this study, Austrian pine (Pinus nigra Arnold) seedlings grown from seed collected from 40 open-pollinated families from five Balkan Peninsula provenances were evaluated for survival and growth under imposed drought. Within each provenance, seed was collected from an extremely harsh habitat and from a favorable habitat. One-year-old seedlings, from each provenance, habitat type and open pollinated family were transplanted into three “stressbeds”, each designed to simulate different levels of water availability by filling with varying ratios of crushed stone and soil. Seedling height growth and survival were recorded every 20–30?days from April–September. In all provenances, seedlings grown from seed originating from the harsh habitats had lower survival regardless of stressbed treatment compared to those grown from seed collected from favorable habitats, with the exception of one population from the Vi?egrad provenance which had high survival rates throughout. Overall height growth was very low and did not follow consistent patterns among treatment groups. Cluster analyses of survival data showed that populations from a similar habitat generally grouped together, regardless of provenance. The lowest and highest survival values were found in seedlings from harsh habitats, while those from the favorable habitats clustered in the mid-range. These results suggest that higher seed quality from productive stands may be the most influential factor determining seedling vigor under drought stress and that genetic adaptation to drought was not detected in adjacent populations having different habitat conditions.  相似文献   

2.
对芳樟组培、扦插和嫁接苗的幼林生长节律和生物量的积累及分配格局进行了分析,结果表明:芳樟无性系6-11月生长较快,12月到翌年1月生长缓慢,2-3月又恢复高生长量.生长性状大小排序:组培苗>扦插苗>嫁接苗.生物量的分配各不一致,组培苗:枝>茎>叶>根;嫁接苗:枝>茎>根>叶;扦插苗:枝>茎>根>叶.不同类型幼树主要器官生物量的分布,根部:嫁接苗>扦插苗>组培苗;枝:组培苗>扦插苗>嫁接苗;叶:嫁接苗>扦插苗>组培苗.  相似文献   

3.
We have extracted total DNA from different fractions of fresh wood as well as from cold-stored and air-dried wood harvested from transgenic aspen grown in the field. The highest amounts of DNA were obtained from bark/cambium tissue; the DNA quality, however, was poor. Best results in PCR and Southern blot analyses were obtained from DNA extracted from early wood. Using appropriate primer pairs, amplification products were obtained from both the foreign gene (transgene) and aspen genomic sequences. In Southern blot analyses transgene-specific hybridisation signals were obtained. This is the first report on the detection of foreign genes in wood sampled from genetically modified trees.  相似文献   

4.
为了掌握不同产地‘澳洲青苹’的果实形态及品质特征,从而为‘澳洲青苹’生态区划研究奠定基础,分别从11个产地采集了‘澳洲青苹’果实样品,并就其横径、纵径、果形指数、单果质量、硬度、可滴定酸、可溶性固形物、糖酸比、维生素C含量和出汁率等形态与品质指标进行了测定与差异性分析。结果表明:不同产地‘澳洲青苹’的果实形态和品质特征间均存在一定的差异,其中,果实横径、纵径和果形指数间的差异均相对较小,各产地‘澳洲青苹’的果形指数普遍在0.8~0.9之间,其果实接近于圆形或近圆形;而其单果质量和果肉硬度间的差异均较大,其中,单果质量以辽宁绥中产地的为最大(221.0 g);果肉硬度和果实中可溶性固形物的含量,均以甘肃清水县产地的为最高,分别为10.8 kg·cm-2和12.95%;可滴定酸含量,宁夏银川产地的最高(0.9%),山东栖霞市产地的最低(0.63%);VC含量,甘肃清水县产地的最高(达157.1 mg·g-1),陕西眉县产地的最低(115.1 mg·g-1);各产地的‘澳洲青苹’其出汁率间的差异相对较小,其出汁率在68.9%~76.8%之间。  相似文献   

5.
Han KH  Shin DI  Keathley DE 《Tree physiology》1997,17(10):671-675
We studied the in vitro responses of cambial tissue and dormant vegetative buds obtained from top and epicormic branches of three mature black locust (Robinia pseudoacacia L.) trees. Cambial tissues isolated from epicormic branches produced more callus than cambial tissues isolated from top branches, whereas in vitro shoot cultures derived from buds excised from top branches grew faster than those derived from buds excised from epicormic branches. There were no significant differences between the two branch sources in in vitro bud break or shoot multiplication from bud explants or cambial-derived callus tissue, respectively. Furthermore, the top branches, generally considered to be the most mature in a tree, were not recalcitrant in terms of morphogenic capacity compared to epicormic branches.  相似文献   

6.
根据1999年和2008年公益林区两期的森林资源调查数据,采用对比分析和数理统计方法,从时间尺度上对公益林区的森林资源格局动态变化情况进行了研究,掌握了莲都区公益林在林龄、郁闭度、疏密度、森林类型等方面的变化情况。通过1999年到2008年的十年建设,幼、中龄林与近、成、过熟林面积比例由78:22演变到40:60,蓄积比由54:46演变到23:77;低郁闭度(郁闭度小于0.7)林分由76.57%下降到25.14%,高郁闭度林分则从23.43%上升到74.86%;阔叶林面积占比从11.43%增加到11.57%,针阔混交林面积从26.86%增加到40.29%;单位面积平均蓄积从25.65 m3·hm-2增长到37.95 m3·hm-2,年均净增率4.30%。  相似文献   

7.
This study aims to estimate stand density and stand volume in Cryptomeria japonica and Chamaecyparis obtusa stands from high-resolution satellite data and verify the reliability and uncertainty of the data. Sixty circular sample plots of 0.04 ha each were established. Their stand densities were estimated from the number of tree crowns derived from high-resolution satellite data using the watershed method. Stand densities derived from field surveys in the sample plots were compared with those obtained from high-resolution satellite data by stand age class. As a result, there was a positive correlation between them for sample plots of 41 years of age and over (R = 0.82); however, there was no correlation between them for sample plots of 40 years and under. Individual diameters at breast height (DBH) were estimated from crown areas obtained from high-resolution satellite data for the two species. Using the estimated DBH, individual tree heights were predicted from the height–diameter curves. Stand volumes were estimated from the sum of individual volumes, which were derived from volume formulas having two variables, i.e., DBH and height. Stand volumes derived from the field survey were compared with those obtained from high-resolution satellite data. The correlation coefficient between them for stands of 41 years of age and over was 0.78.  相似文献   

8.
1992~1994年在玉溪市刺桐关林区对云南松纵坑切梢小蠹成虫进行了系统的调查。据系统观测,成虫梢转干历期约143天;干转梢历期约为129天;梢转干的高峰期为每年的1月24日~2月10日,计18天,期间累计成虫数占总虫数的66.65%;干转梢高峰为每年的5月5~25日,计21天,期间累计成虫数占总虫数的64.56%。为便于监测测报,对成虫梢转干、干转梢过程中当地林木相应的物候期进行了观察  相似文献   

9.
橡胶树品种及凝固工艺对天然橡胶性能的影响   总被引:1,自引:0,他引:1  
测定了天然橡胶不同品种和不同凝固工艺制得的生胶门尼粘度值、混炼胶的硫化特性和硫化胶的力学性能,结果表明:不同品种的生胶门尼粘度值存在差异,不同凝固工艺的生胶门尼粘度值差异更为明显,自然凝固的生胶比乙酸凝固的门尼粘度值高;不同品种的混炼胶的硫化特性存在差异,不同凝固工艺混炼胶的硫化特性差异更加显著,自然凝固的混炼胶正硫化时间明显比乙酸凝固的短,最大转矩也比乙酸凝固的混炼胶大;不同品种的硫化胶的力学性能存在差异,不同凝固工艺的硫化胶的力学性能差异更为显著,自然凝固的硫化胶的综合力学性能优于乙酸凝固的硫化胶。  相似文献   

10.
研究液化产物树脂化合成工艺,表征液化木基酚醛树脂的物化性质,评价树脂的胶合强度和木破率.结果表明,采用一次缩聚的投料方式能简化操作工艺,缩短合成时间.木材液化产物中残渣的过滤与否,对树脂性能有一定程度的影响:残渣含量高时,影响较大;残渣含量低时,影响较小.当甲醛与苯酚的量比为1.5和1.8时,利用含11.0%残渣的杉木液化产物和含16.5%残渣的杨木液化产物,制备了性能优良的酚醛树脂.  相似文献   

11.
在全光下应用双长臂旋转扫描喷雾装置进行水曲柳(Fraxinusmandshurica)扦插试验,通过对插穗的母树年龄、伐根萌条的枝条部位、切口形状、ABT生根粉配置浓度等指标的研究,结果显示,从10、15年生树冠上剪取1、2、3年生枝条,40年生树冠上剪取2、3年生枝条,40年生伐根上剪取1年生枝条做插穗,对生根率的影响差异达到了极显著水平,按生根率高低排序:伐根当年萌生枝条84.76%>10年树的1年枝条82.5%>15年生树的1年枝条79.68%>10年生树的2年枝条56.21%>15年生树的2年枝条55.63%>10年生树3年枝条52.46%>15年生树3年枝条50.62%>40年生树冠的2年生枝条48.36%>40年生树冠的3年生枝条45.59%,切口形状、ABT生根粉浓度和浸泡插穗基部时间对生根率的影响差异极显著,插穗以斜切口,ABT生根粉浓度用质量分数为2.0×10-4的溶液,浸泡插穗基部根时间以4 h为最佳组合,平均生根率为84.76%,最高为93.14%,伐根萌生枝条部位对生根率的影响差异不显著。  相似文献   

12.
4个银杏主要产区的银杏花粉营养成分比较研究   总被引:2,自引:0,他引:2  
以4个银杏主产区百年银杏雄树花粉为材料,分别测定了花粉中黄酮、内酯、VC、VB1、VB2、氨基酸的含量,结果表明:四大产区的银杏花粉营养成分存在显著差异,总黄酮、内酯、VC、VB1、VB2、氨基酸平均含量分别为18.760 1 mg/g、5.159 6 mg/g、14.955 6 mg/100g、12.948 3 mg/100g、65.071 5 mg/100g、23.649 4 g/100g,泰兴和南雄的总黄酮含量较高,分别为20.446 5 mg/g和19.579 9 mg/g;南雄地区的内酯含量最高,为7.822 0 mg/g,郯城地区的最少,为2.899 5 mg/g;泰兴的花粉VC含量最高,为27.219 8 mg/100g,桂林地区的含量最少,为6.365 4 mg/100g;桂林地区的VB1含量最多,为22.391 9 mg/100g,泰兴地区的最少,为7.234 7 mg/100g;桂林地区的花粉VB2含量最多,为93.6442 mg/100g,郯城地区的最少,为49.655 0 mg/100g。总体来看,银杏花粉的品质比较优秀,但开发应因地而异,结合营养元素含量有针对性地进行开发。  相似文献   

13.
Root morphology, biomass, and (14)C distribution were studied in two 2-year-old Populus trichocarpa x P. deltoides hybrids, which originated from hardwood cuttings, to determine the pattern of root distribution in a plantation and to refine methods for root recovery. The trees were labeled with (14)CO(2) and harvested after a 72-hour chase period. Roots attached to each labeled tree were analyzed for morphological traits at the time of harvest. Detached roots from within a 1-m(3) volume of soil surrounding each tree were separated from the soil and sorted on the basis of rooting depth and root diameter. Lateral roots > 2 mm in diameter had a largely horizontal orientation at their point of origin from the cutting and extended horizontally up to 4 m from the cutting. This resulted in considerable overlap of root systems in the plantation. Results from (14)C labeling indicated that 24 +/- 4% (+/- SD) of the carbon exported from branches-labeled within two weeks after branch budset-was translocated to the root system. Dilution of the root (14)C label indicated that from 0 (> 5 mm diameter roots) to 75% (< 2 mm diameter roots) of the roots recovered from within the 1-m(3) volume of soil surrounding a harvested tree originated from other trees. Total root biomass was 6 +/- 1 Mg ha(-1) for both hybrids. Sixty percent of the root biomass was recovered directly from excavation, 16% from coarse-sieving excavated soil, and 24% from re-sorting sieved soil. The study indicated that root growth of hybrid poplars may be rapid and extensive and that detailed sorting of soil subsamples substantially improves the recovery of fine roots < 2 mm in diameter.  相似文献   

14.
以3个非洲菊品种的叶柄为材料,研究了不同激素及其浓度对非洲菊离体培养再生的影响。结果表明:3个品种的叶柄在含单一细胞分裂素6-BA的培养基上培养时都不能被诱导出愈伤组织;而在仅含生长素NAA的培养基上培养时均可被诱导出愈伤组织,并且在其愈伤组织发生部位都有不定根发生,但只有品种6267能从不定根发生部位直接分化出不定芽;当在含NAA的培养基上再附加6-BA时也可被诱导出愈伤组织,但无不定根发生。所产生的愈伤组织在分化培养基上培养时只有由品种Ⅱ叶柄在同时含有NAA和6-BA的诱导培养基上产生的愈伤组织才可以分化出不定芽。表明愈伤组织的诱导与分化、不定芽和不定根的发生与品种及培养基中的激素种类有关。  相似文献   

15.
兴凯赤松与樟子松苗期生长性状对比分析   总被引:1,自引:0,他引:1  
在优异种质选择基础上,引进3个兴凯赤松、5个樟子松天然群体的种子,经有性繁殖获得植株,以此开展种质资源异地保存林营建技术的研究。结果表明:兴凯赤松苗期高生长节律与樟子松相近,且适应性较强,定植成活率较高;樟子松群体内生长性状变异较大,变异幅度30.11%~46.72%(苗高)、23.33%~35.98%(地径);群体内及群体间兴凯赤松生长性状变异较小,变异幅度在30.27%~31.47%(苗高)、24.81%~25.05%(地径)之间,并且,兴凯赤松苗高和地径生长量较樟子松分别提高30.23%、29.40%。  相似文献   

16.
研究分析了浙江宁波市象山松兰山景区松材线虫病发生规律与防治效果。结果表明:只采取“封锁”措施,会使松材线虫病迅速爆发毁灭全林。从1992年到1998年,松兰山枯死松树从6株增到5893l株,增长了9820.8倍;采用皆伐松林防治松材线虫病并改造成板栗、杨梅的方法,会导致逆向演替,使松林最后成为以疏花野青茅为主的荒山。而采取综合防治措施就可有效地控制松材线虫病的危害。从1998年到2002年,松兰山枯死松树下降到137株,缩小了430倍,使松兰山仍然保持着葱郁的松林群落。  相似文献   

17.
Ultrastructural abnormalities in phloem albuminous cells of needles of young pine seedlings from two Finnish nurseries suffering from the growth disturbances of conifer seedlings were studied. Needle samples were taken from growth disturbed seedlings and from healthy looking nursery seedlings as well as from naturally born forest seedlings. The results are discussed in relation to the possibility of virus disease in growth disturbed seedlings. The first trials to observe the viruslike particles from abnormal seedlings will be discussed, too.  相似文献   

18.
2000~2005年,每年春季分别在闽北7个国有林场用广西马尾松种子园和福建漳平五一国有林场马尾松种子园的种子育苗、造林,通过2005年的调查数据分析结果表明:广西马尾松良种在同一地点,树高、地径生长好于漳平马尾松良种,冠幅生长性状基本相等;广西马尾松良种在南平樟湖国有林场栽培效果最佳,漳平马尾松良种在浦城大庄国有林场栽培效果最佳,本地马尾松以建瓯水西国有林场生长最佳,广西马尾松良种更适合于纬度较低、积温较高的地区发展。  相似文献   

19.
新造毛竹种源竹鞭生长规律研究   总被引:1,自引:0,他引:1  
通过对 9个种源的竹鞭生长调查表明 ,各种源鞭径、鞭段长、鞭段数、总鞭长、鞭幅、鞭深等指标 ,都随造林年限的延长而增大 ,但鞭节长随时间没有呈明显的变化规律。鞭径以中带、北带为好 ;鞭段长以南带最大 ,总鞭长均为南带 >中带 >北带。从鞭幅看也为南带的最大 ,分布深度以北带为深。鞭节以北带和中带鞭节较长。从总体看 ,竹鞭生长各指标以福建武夷山较好 ,广东从化最差。研究结果为毛竹经营提供参考  相似文献   

20.
To investigate the taxonomy of Heterobasidion in Eurasia, 49 specimens belonging to H. annosum sensu lato from Asia were identified with the aid of mating tests. Most of the specimens originated from north‐eastern and south‐western China and from the Altai region in southern Siberia, but a few isolates from Kirghizia, Japan and India were also tested. In addition to mating tests, the material from China was investigated with DNA fingerprinting. Heterobasidion annosum sensu stricto was identified only from the Altai region. Homokaryotic isolates from other specimens, except the Indian ones, were sexually compatible with H. parviporum, but they also showed a high degree of compatibility with H. abietinum and with the North American S group. The isolates from SW China (eastern Himalayas) mated with about equal frequency with the European strains of H. parviporum and H. abietinum. However, the DNA fingerprinting showed that these isolates were more closely related to H. parviporum, and hence they were tentatively included in this species. The North American S group was more distant from these Eurasian taxa. Four old isolates from India mated only weakly with the members of the H. annosum s.lat. According to the species concept presented, the distribution of H. parviporum extends from western Europe through southern Siberia to northern China, Japan and the eastern Himalayas. H. annosum s.str. is so far identified only from the Altai region outside Europe, and H. abietinum only from Europe.  相似文献   

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