杨树体细胞胚状体的诱导发生

胚状体是植物组织培养中起源于一个非合子细胞,经过胚胎发生和发育过程形成的胚状结构。它具有分化频率高、繁殖速度快的特点。自1958年 Steward 等人用胡萝卜细胞悬浮培养获得胚状体以来,在国际上引起了广泛的注意。近20年,用离体培养方法已经在34科、75属、117种植物中诱导产生了胚状体。1978年我国广西柳城甘蔗研究所又从单子叶植物甘蔗的体细胞中,诱导产生了胚性细胞团,它能连续继代增殖胚状体。但在     

香樟未成熟合子胚体胚发生及植株再生研究

以香樟的未成熟幼胚为外植体进行诱导体胚发生影响因素的研究.成功地从香樟幼胚中诱导出胚状体并获得再生植株,MS为基本培养基,蔗糖是最佳的碳源.经2年对初生胚的继代培养,获得胚性愈伤组织;胚性愈伤组织经体胚诱导、体胚成熟、体胚萌发3个过程的诱导后能够获得再生植株.     

三倍体毛白杨叶片培养和快速繁殖

采用三倍体毛白杨嫩叶进行组培快繁，以附加NAA的MS培养基诱导的愈伤组织，可产生大量胚状体细胞，转接培养后能形成组培苗。组培苗在MS＋IBA0.25mg/L 0.5%碳粉的培养基上20d左右开始生根，经过炼苗处理，即可移栽到大田定植。     

茶树子叶离体培养形成胚状体的研究

采用改良的ER培养基,附加不同种类的植物生长调节物质,使茶树接近成熟的种子的子叶基部及子叶柄形成胚状体。详细观察了胚状体形成过程中形态学上和细胞组织学上的变化。初步肯定了胚状体起源于子叶表皮细胞;胚状体在胚胎发生的最初分隔方式上与合子胚不同,发育过程与合子胚较一致。进一步观察到不同种类的植物生长调节物质的用量及配合用量影响胚状体的分化及小植株的形成。并详细介绍了茶树组培苗移栽成活的方法。     

丽江云杉体细胞胚胎发生

体细胞胚胎发生是细胞工程中植株再生的重要途径之一,可作为基因工程的受体系统,同时也是研究细胞全能性、细胞分化及其形态建成的理想试验体系.在应用上,体细胞胚胎发生是一种有效的大.规模无性繁殖方法(郭奕明等,2003;贾彩凤等,2006;Stasolla et al.,2003;Sutton,2002).在目前已成功诱导体胚形成的植物中,草本植物占了大多数.已有40多种木本植物获得了体细胞胚,尤其是用常规无性繁殖技术很难生根的针叶树的体胚发生研究取得了令人瞩目的进展,20多种不同的针叶树的外植体成功诱导出体细胞胚(施季森,2000).     

移植基质对枣组培苗移植成活率的影响

应用林木果树繁殖中心组培技术，获得的枣树试管组培苗，选择塑料大棚自动弥雾技术，给移植苗适宜的环境，采用不同的移植基质进行试验，成功地为生产应用获得大量大量枣无病毒苗。     

棕榈藤组培技术研究*

经对单叶省藤、黄藤和白藤组织培养系列试验证明：半成熟种胚是棕榈藤组织培养最佳外植体，在ＲＭ５－１和ＲＭ８－２培养基中，相继各培养５０ｄ，即形成完整的试管苗；外植体在总盐浓度为６８９９ｍｇ／Ｌ的培养基中，置于６９０ １ｘ光照度下每天照射１６ｈ诱导愈伤组织效果最好；ＲＭ６是丛芽诱导和继代培养最理想培养基。一个外殖体经一年的培养增殖，其理论繁殖系数为２．８×１０＾５／ａ。组培诱导分化的丛生苗切片显微观测     

百合的组织培养及在其育种中的应用

对百合组织培养的进展状况及组织培养在百合育种中的应用作了综述。着重介绍了百合组织培养中所选用的外植体类型和一些组培材料的最佳分化、继代、生根培养基配方；从远缘杂交中通过胚培养获得杂交种，通过花药和未授粉子房培养获得单倍体植株，离体条件下秋水仙素处理诱导产生多倍体百合。并论述了百合组织培养在其育种中的应用。     

云南松、海岸松胚乳培养初报

1.在 H 培养基附加动力精6—8毫克/升,2、4—D4—6毫克/升,萘乙酸2—4毫克/升的变动范围内,仅20天左右的时间诱导出了云南松胚状体,45天诱导出海岸松胚状体。2.通常萘乙酸,2、4—D 不同时使用,而本试验是在二者兼用的情况下产生的胚状体,同时经过重复,所用动力精与生长素水平高于一般用量。3.这一培养基再加修改有诱导出苗的希望,同时可以探索一次成苗的途径。4.胚状体的分化与胚乳组织颜色的变化密切相关,有待研究。     

橡胶树胚珠离体培养与体胚植株再生的研究

对8个品种橡胶树未授精胚珠离体培养试验结果,8个品种都诱导出愈伤组织,其中6个品种诱导出胚状体,3个品种获得体胚植株。试验结果表明:不同品种橡胶树未授精胚珠在诱导愈伤组织、继代增殖、胚分化和植株再生培养存在很大差异,热研8-79、云研73-46愈伤组织的诱导率高,但未能分化出胚状体;云研73-477、RRII105等品种,愈伤组织的诱导率低,但继代增殖培养时能诱导出新鲜的胚性愈伤组织,获得体胚植株;云研77-2、云研77-4诱导出的是畸形胚,未获体胚植株,但其胚状体诱导率比用花药诱导的高,有希望通过进一步研究,优化培养方法、培养条件,最终构建出这两个抗寒高产优良品种的体胚植株再生体系。     

Rosmarinic acid content and RAPD analysis of in vitro regenerated basil (Ocimum americanum) plants

Various in vitro cultures were established from shoot tips of Ocimum americanum seedlings. Rosmarinic acid content of the in vitro produced plants as well as parent plant were determined by HPLC analysis and subjected to RAPD analysis. MS medium with BA at a concentration of 1 mg/l and 0.25 mg/l IAA supports maximum rosmarinic acid production in plants produced from cultures grown on that medium. RAPD analysis revealed 64 scorable bands from four primers, including six polymorphic bands. The band pattern revealed differences between the parent plant and the in vitro regenerated plants. Certain band changes were found in O. americanum plants regenerated in vitro, suggesting the existence of genetic variation that might affect the biochemical synthesis of plants derived from tissue culture.     

Micropropagation and tissue culture of Eucalyptus-a review

Micropropagation has the potential to provide very high multiplication rates of selected tree genotypes, with resulting short-term silvicultural gains. Aseptic cultures have been established from seeds, seedlings, shoots, flowers and lignotubers. Callus cultures have been established from a wide range of tissue sources for at least 30 species of Eucalyptus. Plant regeneration from callus was successful for 12 of these species. Micropropagation through axillary proliferation, or adventitious shoot proliferation on nodal explants, or both, has been successful. An agar-based medium of Murashige and Skoog with a low auxin/cytokinin ratio is most commonly used for shoot multiplication. Vitrification and shoot senescence remain problems. Gibberellic acid was added in some media to stimulate shoot elongation. Various media are used for in vitro root initiation. Suspension and protoplast cultures have been achieved and plants have been regenerated from protoplasts. In vitro techniques are presently being applied to Eucalyptus to achieve genetic transformations.     

草类-小檗沙棘灌木林群丛不同树种更新效果评价

为研究草类-小檗沙棘灌木林群丛不同树种更新效果,选择草类-小檗沙棘灌木林群丛不同微环境,设更新幼苗树种(A因素)和更新幼苗与灌木之间的距离(B因素)两组水平搭配,A因素设计A1(山杨苗)和A2(青海云杉苗)2个水平;B因素设计B_1(0.25m~2)、B_2(1.0 2)、B_3(4.0m~2)、B_4(≥9.0m~2)等4个水平,调查更新成活率、生长量。试验结果表明:(1)山杨更新幼苗与灌木之间的距离对山杨更新幼苗生长的影响显著;在B3(更新幼苗在4.0m~2中央即2.0m×2.0m左右)山杨幼苗生长效果最好,成活率达到78.6%。(2)青海云杉更新幼苗与灌木之间距离对更新幼苗生长的影响显著。在B1(更新幼苗在0.25m~2左右中央即0.5m×0.5m)幼苗生长效果最好,成活率达到96.7%.(3)在草类—小檗沙棘群丛条件下,采用青海云杉更新比山杨效果好。     

From planting to 26 years of age – actual growth and estimated volume scenarios for spruces and pines

The objective of this study was to compare the survival and volume of conifer stands at 26 years of age with their status at planting. Survival, growth and damage were studied in eight clear felled stands regenerated in 1972. Five of the areas were planted with Norway spruce (Picea abies (L.) Karst.) and three with Scots pine (Pinus sylvestris L.). The plantings were examined in 1972 and 1974. In 1974, the number of living undamaged planted seedlings was low (10–15%). However, the number of undamaged seedlings was supplemented by naturally regenerated conifer and birch seedlings. The total number of undamaged seedling in 1974 was equivalent to 20–30% of the number of seedlings planted. In 1998, the main species in three stands had changed from Norway spruce to Scots pine, and in one stand from Norway spruce to birches. Actual volume in 1998 for the stands was compared to stand volume generate according to five scenarios based on recommended and actual seedling number in 1972 and 1974. The actual volume was 64% of that expected if the recommended number of trees had been planted. Naturally regenerated Scots pine and Norway spruce increased stand density in 1998. The actual volume was 37% higher than the average volume in the surrounding county. On average, 36% of the trees were damaged. More than 50% of the total damage was caused by moose (Alces alces L.). For Scots pine, moose or other browsing animals damaged 30% of the trees. The results of this study indicate that the 1998 volume was higher than expected, considering the low number of undamaged seedlings in 1974. This was mainly due to the large amount of naturally regenerated plants. In addition, the results indicate that the volume could have been higher if the initial conditions had been better. Despite the low number of undamaged seedlings in 1974, seven of the eight studied stands produced a higher volume than the average stand for the region. In practise, high numbers of seedlings should be planted on scarified areas. In most cases there will be a supply of naturally regenerated seedlings.     

Naturally established seedlings on an artificially regenerated area in Northern Sweden

A field experiment in northern Sweden was established to compare different regeneration methods. Pinus sylvestris (L.) seeds of various origins were used. On the plots on the clear‐felled area where local seed had been sown, the naturally established conifer regeneration was recorded. Eleven growing seasons after sowing, the total number of seedlings increased by 335% giving a total of 4 754 seedlings ha^‐1 when the number of naturally established conifers was added to the number of seedlings from the artificial regeneration. The number of main crop plants almost doubled. The number of naturally established seedlings decreased with increasing distance from the neighboring seed‐tree stand. Up to 110 m from the seed‐tree stand 50% of the sowed 2 × 2 m quadrats had at least one naturally regenerated seedling. The extent of natural regeneration found in this study suggest that it could contribute to a significant increase in stand density under appropriate management on suitable sites. Moreover, naturally established seedlings on artificially regenerated sites may serve as an insurance factor in future perturbations, lead to better tree form shaping conditions and maintain genetic diversity even if material from a narrow genetic base is used for planting or sowing.     

Field performance of Pinus contorta trees propagated vegetatively via adventitious buds

Abstract

Pinus contorta plants regenerated from adventitious buds induced on zygotic embryos were planted in a field trial where growth, straightness and flowering were followed over 7 years. Seedlings were taller than the plants derived from adventitious buds at the start of the field trial. Adventitious plants did not catch up with seedlings in height after 7 years in the field, but the relative height growth was equal. The higher frequency of plagiotropic growth that was displayed by adventitious plants the first year in the field was not reflected by differences in the frequency of basal sweeps 6 years later. However, the frequency of crooked stems was comparatively high but similar among the plant types. Flowering was more abundant for the seedlings than for adventitious plants. Taken together, the results show that P. contorta can be cloned via adventitious buds from zygotic embryos, and that the resulting plants show satisfactory growth for inclusion in breeding.     

Effects of low night temperature and light on chlorophyll fluorescence of field-grown seedlings of Scots pine (Pinus sylvestris L.)

In vivo chlorophyll fluorescence kinetics was observed in naturally regenerated and planted Scots pine (Pinus sylvestris L.) seedlings growing at two adjacent sites in northern Sweden. Some seedlings were shaded from direct solar radiation and some were protected from frost at night. Air temperature and solar radiation were monitored. In vivo chlorophyll fluorescence kinetics of current-year needles was measured at both room temperature and 77 K. On clear days during August, variable fluorescence of photosystem II of needles from exposed, naturally regenerated seedlings was reduced by night frosts, whereas frost caused little change in fluorescence of needles from shaded seedlings. Overnight frost-protection reduced the inhibition of photosystem II by direct sunlight. Recovery from photoinhibitory damage occurred on cloudy days. In September, the decline of variable fluorescence of photosystem II was more pronounced in unshaded than in shaded seedlings, and coincided with frosts at night. In addition, the reduction in variable fluorescence was larger for planted seedlings than for naturally regenerated seedlings. It is suggested that the inhibition of photosystem II activity was caused by an interaction between low temperatures and light. Natural night frosts are proposed to increase the susceptibility to photoinhibition in the following day(s).     

间伐对川中丘陵区人工柏木林下天然更新的影响

以川中丘陵区"带状采伐+补阔"试验基地作为研究对象,调查其林下天然更新情况。结果表明:(1)采伐带、保留带天然更新的幼树幼苗明显高于对照样地(P<0.05)。10m、8 m、6 m、4m采伐带、保留带的天然更新幼树幼苗分别是对照的10.63倍、9.38倍、7.92倍、7.50倍和3.33倍、3.75倍、4.38倍、6.04倍。(2)采伐带、保留带、对照样地内的更新幼树幼苗的树高均显现为左偏单峰结构,且均以树高≤0.1m的幼苗数量最多。不同带宽采伐带和保留带内天然更新的幼树幼苗高度分级占比不尽相同。(3)所有处理下的天然更新的幼树幼苗均呈聚集状分布的状态,且聚集强度较大。(4)除柏木外,天然更新的树种种类多以香樟、香椿、乌桕等喜阳或半喜阳的为主。     

植物种子际微生物研究进展

很多林木种子存在难萌发、天然更新不良的现象，而种子际是直接影响种子萌发的土壤区域，种子际微生物会对天然更新的植物产生有益或有害的影响，并对解释根际微生物群落的建立具有重要的意义。文中主要从种子际微生物多样性、对种子和幼苗生长发育的影响、种子际微生物群落变化的影响因素以及种子际微生物的自身调节行为等4方面来概述种子际微生物研究现状，分析种子际微生物研究中存在的问题，提出未来林木种子际微生物的研究展望，旨在为林木种子建立共生萌发机制及为濒危物种野生居群的生态恢复提供参考。     

Agrobacterium tumefaciens-mediated GUS gene transformation of Robinia pseudoacacia ''''Idaho''''

Based on the plant regeneration system, a GUS gene transformation system to Idaho locust (Robinia pseudoacacia 'Idaho') mediated by Agrobacterium tumefaciens was established. The successful transformation was confirmed by regenerating the shoots from the infected leaves in the presence of hygromysin; by histochemical X-gluc assays ofβ-glucuronidase (GUS) and by PCR and PCR-Southern blotting analysis. The ratio of positive transgenic plants is 5.8% (5 out of 86 plants). With this system, the target gene DREB was introduced into the leaves of Idaho locust. The transgenic plants regenerated, which was verified by PCR-Southern blotting. It is suggested that the transformation system could be a new, simple, reliable and practical route to gene transformation of R. pseudoacacia 'Idaho' mediated with A. tumefaciens.