生物技术在竹类植物上的应用进展与前景

当前生物技术在竹子上的应用主要可归纳为竹子快繁、组织与细胞培养、开花人工诱导和遗传改良四个方面。竹子快繁技术集中于丛生竹幼枝的离体培养，已有4个竹种在生产上应用；组织与细胞培养在60多个竹种上获得成功；开花人工诱导对难开花的竹子来说是杂交育种和开花生理生化研究的理想研究系统，在10个竹种中诱导成功；运用生物技术进行竹子遗传改良尚待深入研究。生物技术在竹子上应用的重点应该是珍稀竹种或优良无性系快繁、生理和生化研究、竹子遗传改良。     

林木种子园生殖系统研究进展

本文对种子园生殖系统中亲本开花物候、配子产量、球果和种子败育、授粉机制、球花分布对种子园遗传效率的影响及其研究进展作了综述。论述了开花物候、球花产量与配子贡献以及种子园生殖系统遗传效率的关系。不同亲本开花物候及授粉机制的差异限制了亲本之间的基因交流 ,雌雄球花产量、球果败育及其雌雄球花空间分布的差异都会引起亲本配子贡献的变化 ,并最终影响种子园生殖系统的遗传效率。为提高种子园种子的遗传品质和遗传多样性 ,更系统深入地研究种子园生殖系统是必要的     

Control of the first flowering in forest trees 1

Precocious flowering provides opportunities to shorten a breeding cycle. A tree may flower for the first time when sufficient crown development has occurred and there are enough meristems to support both vegetative and reproductive buds. Precocious flowering can be promoted through the use of cultural techniques, such as photoperiod, accelerated growth, gibberellins and water stress. The length of the juvenile phase is dependent on genetic and environmental variables that affect achievement of a minimum size, and is positively correlated with the height of the plants within a family. Selection pressure can be applied successfully to the precocious flowering character, and crossed or inbred lines of precocious flowering progeny can be developed. Various levels and amounts of genetic control have been implicated in the control of precocious flowering.     

竹类植物基因组学研究进展

概述竹类植物基因组学研究进展,包括RAPD,RFLP,AFLP,ISSR等分子标记的开发与应用,开花、细胞壁生物合成、光合作用、抗逆等相关的重要功能基因研究,基因组测序与比较基因组学等;在分析和综述的基础上,提出竹类植物分子生物学研究基础薄弱、功能基因鉴定困难等不足,并明确遗传转化体系的建立、比较基因组学与功能基因组学研究、分子标记辅助育种是今后竹类植物基因组学研究的重点。     

竹子分子生物学研究进展

从分子生物学角度来探讨竹子问题是竹子研究的新趋势。目前,关于竹子出笋的基因调控机理研究很少,有关竹子开花方面的主要集中于MADS-BOX基因的研究。分子生物学应用最多的是在竹子分类领域,但大多采用分子标记技术,利用同源基因进化研究相对较少。竹子转基因的初步成功为竹子的遗传育种带来了新的希望。另外,分子生物学在竹子花叶病毒研究中发挥着极其重要的作用。在总结已有研究基础上,认为竹子开花分子机理研究是今后竹子分子生物学研究的重点。     

胡枝子属植物的遗传育种研究进展

从遗传资源研究、引种、地理变异及优良种源选择,开花繁殖生物学研究与杂交育种等方面论述了国内外胡枝子属植物遗传育种研究的现状。针对我国在胡枝子属植物研究工作中存在的问题,提出了4点建议。     

芍药周年供花技术研究综述

从温度、光照和植物生长调节剂3个方面综述了芍药(Paeonia lactiflora)促成栽培的关键技术、人为控制芍药花期以及实现周年供花的研究进展,从花芽分化、生理机制与遗传机制3个层面分析了芍药花期调控原理,并探讨了该领域今后的研究方向.     

Identification of ISSR markers linked to flowering traits in a representative sample of <Emphasis Type="Italic">Eucalyptus cladocalyx</Emphasis>

Early flowering and flower abundance have long been considered desirable traits in eucalypt breeding programs. In particular, flowers of Eucalyptus cladocalyx provide a nectar source for the production of honey in arid ecosystems. To identify inter-simple sequence repeat (ISSR) markers that are associated with early flowering and flower abundance in the southern Atacama Desert, we used a sample of 47 trees, representing five Australian provenances of E. cladocalyx. A unified mixed linear model (which considered the effect of genetic structure and the kinship relationship among trees) revealed that three loci were significantly associated with early flowering, which accounted for 10–16 % of the phenotypic variation, while two loci accounted for 11–13 % in flowering intensity. Locus ISO_{1–500 bp} was associated with both flowering traits. This result is consistent with our previous findings indicating that marker-assisted selection on early flowering should have significant and positive impact on flowering intensity. The application of marker-assisted selection to identify trees that flower early and intensively may increase honey production, a resource that generates additional income for the local farmers of the southern Atacama Desert.     

竹子遗传改良技术研究进展

竹子生长快、周期短、用途广泛,具有重要的经济价值和生态效益。由于竹子的开花周期长、结实率低,新品种培育极为困难,极大地影响了竹产业的可持续发展,因此如何有效地开展竹子育种工作成为国内外研究者关注的焦点。文中在介绍竹子组织培养和遗传转化研究成果的基础上,重点综述近年来竹子再生过程中外植体的类型和发育阶段、培养基的选择、生长调节剂和添加物的使用以及遗传转化过程中农杆菌菌液浓度、培养条件等方面的研究现状,讨论了竹子遗传改良技术目前存在的问题,并对该技术未来研究方向进行展望,以期对今后该领域的研究工作提供借鉴。     

白桦转基因遗传改良研究进展

随着科学技术深入发展, 转基因技术已经成为林木定向遗传改良的重要途径之一, 林木基因工程也随着转基因技术的成熟而步入快速发展时期。目前国内对白桦(Betula platyphylla)的研究处于常规育种向分子育种的过渡阶段, 转基因技术在白桦定向培育过程中的应用才刚刚起步。文中从白桦开花、抗虫、木材改良、抗非生物胁迫等方面总结了国内外白桦转基因研究现状, 对转基因技术在白桦遗传改良种应用中存在的问题进行探讨, 展望了转基因技术在白桦遗传改良中的应用前景, 以期为白桦基因工程研究提供参考。     

马尾松二代种子园无性系开花物候观测

[目的]在用材林高世代种子园建园材料选择时,最初重点考虑的是其速生性,而对优树的开花物候关注较少。在高世代种子园营建时,无性系的配置常根据其种源在大范围内考虑其开花物候的遗传因素,但即使是小范围内相同种源的无性系,其开花物候也不可能绝对同步。因此,了解种子园无性系的开花物候,可为种子园的集约经营、产量预测、种子遗传品质调控等提供依据。[方法]于2012—2013年,在桂阳县苗圃马尾松二代种子园Ⅰ大区、Ⅴ大区分别随机选取不同类型的无性系10个和25个,对其开花物候进行观测。[结果]表明:不同无性系的雌、雄球花花期起止日期和持续时间均有差异,但无性系间雌、雄球花花期值差异均未达显著水平,35个无性系总体雌、雄球花花期具有一定的同步性;35个无性系雌、雄球花的初花期基本同步,雌、雄球花的盛花期和末花期同步。株间花期差异相对于无性间要大,但雄球花花期较早的植株,其雌球花花期也较早,同一株建园亲本的雌、雄球花花期有一定的同步性。除雌球花的末花期与雄球花的初花期呈微弱负相关外,雌、雄球花的初花期、盛花期、末花期间均呈极显著或显著正相关。各花期的相关性呈现初花期和盛花期的相关盛花期和末花期的相关初花期和末花期的相关,雌球花初花期与雄球花初花期的相关系数最大。坡位对母树的花期有极显著影响,生长在不同坡位的植株,其雌、雄球花花期值差异明显,其大小均为上坡中坡下坡。坡位对花期影响最大的是雌球花的初花期,其次是雄球花的初花期、雌球花的盛花期、雄球花的盛花期,而对雌、雄球花的末花期影响最小。偏北产地无性系的花期相对较早,不同的无性系类型,其雄球花的盛花期和雌球花的初花期的差异显著;雄球花的初花期、末花期以及雌球花的盛花期和末花期差异均不显著。不同的年份,雌、雄球花花期的早晚差异很大,2012年最早初花期较2013年最早初花期早25 d。[结论]桂阳马尾松二代种子园35个无性系总体雌、雄球花花期具有较好的同步性;从开花物候方面考虑,该种子园建园材料选择较合理,对种子园种子产量和遗传品质没有影响。     

竹类植物分子生物学研究进展及展望

概述了目前分子生物学方法在竹类植物上的应用,包括其核酸提取的方法、分子标记(RFLP、RAPD、SCAR s、AFLP及微卫星)等在分类上的应用,竹类开花基因等有用基因的分离、鉴定及其转化研究。针对竹类植物的分子生物学研究现状存在的问题包括生物技术育种和系统演化研究,提出了今后竹类植物研究的重点和发展方向。     

Prospects for Enhancing Flowering of Conifers and Broadleaves of Potential Silvicultural Importance in Britain

Research on enhancing coning in commercially important conifers(gymnosperms) is reviewed. The prospects for enhancing flowering,for the purposes of breeding and seed supply, appear good, particularlyfor members of the Pinaceae. The most successful techniquesinvolve the application of the gibberellin A₄ and A₇ mixturecombined with cultural treatments such as drought, root pruningor girdling. There is scope for these techniques to be usedin outdoor seed orchards but more particularly with container-grownplants in polythene houses. Less research has been publishedon enhancing flowering in broadleaves (angiosperms) though therehas been considerable attention to factors affecting blossomand fruit development. Techniques that encourage rapid vegetativegrowth so that plants quickly reach a certain minimum size maybe the most promising to promote flowering of broadleaves. Avenuesfor further research are considered.     

榛子杂交育种中的平榛花粉制备关键技术的研究1）

平榛（ Corylus heterophylla Fisch 。）是东北地区的主要经济林树种,其坚果是食用榛子的主要来源。利用平榛进行榛子遗传改良,是培育新品种的重要方法。通过多年的研究总结出一套平榛花粉收集技术,为杂交育种提供了技术的保证。透光率对雄花序生长的影响呈负相关,透光率越低,雄花序开花时间延长,花序也伸的长,花粉产量少;而透光率对花粉产量则相反,透光率越高,雄花序开花时间越短,花粉产量多。雄花生长与花粉产量受种源、水培时间的影响,其差异性显著。     

林木成花分子基础研究进展

多数林木的幼年期长、始花期晚,为了探索林木早花的分子机制,克服经济林木育种周期长的难题,为进一步的林木童期调控和分子育种研究奠定基础,综述了高等植物的成花假说、成花诱导分子机理、林木成花相关基因的克隆及相关生理信号的研究进展．     

水竹开花的生物学特性研究

水竹,刚竹属散生竹种,为长江流域及其以南最常见的野生竹种之一,也是黄河和长江流域广为栽培的一个竹种。自2003年以来,中国四川雅安地区的水竹出现开花现象,到目前已成大范围开花枯死的趋势。对水竹的开花生物学特性进行了研究。结果显示,水竹开花在每个季节均有发生,但主要集中在12月至次年的5月份,开花以后整个植株枯死。水竹为穗状花序,每个佛焰苞(花序)有5～7个假小穗,每个假小穗有4～6朵小花;水竹花丝长约1.8cm,花药黄绿色,柱头三裂。水竹花药非常丰富,但雌蕊发育不良,因此,至今未发现水竹结实。对开花和未开花竹林环境因子进行调查和分析后发现,竹林内光照时数、气温以及湿度对开花有比较显著的影响。同时,开花和未开花水竹根、茎、叶的冷冻切片显示,开花水竹根、茎、叶的细胞结构和发育状况均差于未开花竹。由此看来,内部生理变化和外部环境影响是导致水竹开花的最终原因。     

生物技术在竹类植物研究中的应用及展望

概述了生物技术在竹类植物上的应用,包括组织培养和细胞工程、分子标记、竹子试管开花诱导、遗传转化与基因工程等方面,针对竹类植物的生物技术研究现状,提出了今后竹类植物研究的重点和发展方向。     

Regulation of early flowering in Pinus banksiana

Seedlings of three families of jack pine (Pinus banksiana Lamb.) were subjected to 16 combinations of photoperiod, growth environment (outdoors, greenhouse and biotron) and gibberellin (GA(4/7)) treatment. After 14 months, which included two dormancy induction periods, ovulate flowering was observed. There was a strong positive correlation between flowering and seedling height; female flower production was stimulated by both a declining photoperiod during bud development and GA(4/7) treatment; and there was an interaction between GA(4/7) treatment and family, such that the difference in flowering intensity between a late-flowering and an early-flowering family was eliminated by GA(4/7) treatment. The results suggest that the genetic control over the time of onset of flowering, and GA(4/7)-induction of flowering depend on a common mechanism.     

Somatic embryogenesis, micropropagation and plant regeneration of "Early Mature" walnut trees (Juglans regia) that flower in vitro

Some walnut trees (Juglans regia L.) originating from central Asia display an early flowering phenotype. These "Early Mature" (EM) trees may produce flowers within months of germination. Secondary flowering waves are also observed within a growing season. Inflorescences may carry male, female and hermaphrodite flowers. Progeny obtained from selected EM trees were cultured in vitro to initiate clonal propagation of these genotypes. Embryogenic lines were established through the culture of immature zygotic embryos. Microshoot lines were obtained from germinated somatic or zygotic embryos. Plants showing EM phenotypes were recovered through direct conversion of somatic embryos or adventitious rooting of microcuttings. During the in vitro propagation phase, flower buds were observed on microshoots after three to six subcultures. Histological analysis showed that most of these flowers were hermaphrodite. In vitro apical buds were used to clone the walnut orthologous cDNAs of the AGAMOUS and APETALA 3 MADS-box genes. Northern blots revealed a preferential expression of both of these homeotic genes in flowers. The results highlight the usefulness of EM lines to study the genetic cues controlling flowering and sexual maturity in woody perennials.     

嫁接繁殖研究进展及其在林木遗传改良中的应用前景

嫁接作为一种传统的无性繁殖方法,已广泛应用于农林领域中的良种扩繁保存、品种改良、新品种选育等方面,它能够有效提高作物产量、抗逆性,改变植物的开花结果习性及改良果实品质。文中介绍了嫁接繁殖的特性,并从嫁接愈合解剖学、生理生化、分子机理3个方面对国内外有关嫁接成活机理进行了系统综述;探讨了嫁接引起的遗传变异及其在林木遗传改良中的应用前景,以期为嫁接技术改进及林木遗传改良提供新思路。