对减少油松种子园球果败育和提高球果出籽率的研究

提高油松种子园的种子产量，关键在于减少球果败育和提高球果出籽率。本文的研究结果表明：球果败育与种子园的花粉产量无关；不同无性系球果败育率存在显著和极显著差异；树冠上部的球果败育率显著低于树冠下部；在种子园开花初期，辅助授粉能显著提高球果出籽率。１９８８年卢氏种子园实施辅助授粉后，使球果出籽率提高１．１４％，增产效益３３．９％。辅助授粉对不同无性系提高球果出籽率的作用差异明显。     

影响油松种子园胚珠败育的因素分析

提高球果出籽率是油松种子园种子产量的关键因素之一。在卢氏种子园结实初期胚珠败育率达到了70%,进入盛果期下降到45%。不同无性系间胚珠败育有很大差异,无性系间异交可配性、花期同步和自交是引起胚珠败育的主要因素。在结实初期辅助授粉可以显著提高种子产量,进入盛期后无效,但可以改善种子的遗传组成,增加种子的遗传多样性。     

我国油松种子园开花结实与经营管理技术的研究概况

对油松种子园无性系开花习性、雌雄球花产量及其空间分布规律、球果与种子的产量及性状变异以及施肥、病虫害防治、去劣疏伐和修剪等经营管理技术措施的研究结果进行了系统分析,研究了我国油松种子园开花结实与经营管理技术的研究现状,可为我国油松种子园深化研究与经营管理提供参考。     

马尾松二代无性系种子园的花期同步性

【目的】研究马尾松二代种子园无性系的开花物候特征、花期同步性、结实状况及气候影响因子,评价无性系花期同步性规律,指导种子园经营生产及提高种子遗传品质与产量。【方法】连续2年对浙江省淳安县姥山林场马尾松二代无性系矮化种子园的22个无性系进行花期、花量和结实性状调查,分析其开花物候与花期同步指数。【结果】各无性系雌雄球花整体花期持续时间为8～17天, 2014年始花期相对于2013年滞后约6天,且持续时间缩短约6天。整体水平上,年度内雌球花及雄球花的各花期时长差异较小;无性系的始花期和盛花期的物候特征年度间存在差异, 2014年无性系内雌雄球花开花的同步性更强。无性系的开花物候受气候因素影响较大,这使得无性系间开花同步程度降低,花期同步指数变异增加, 2013年和2014年花期同步指数变化范围分别为0.041～0.556和0.284～0.802,无性系的平均变异系数分别为32.3%和16.8%。各无性系分别作为父、母本时,年度内无性系花期整体同步性水平差异较小,表现出无性系作为父本时的散粉期整体的同步性要高于作为母本时的可授粉期的同步性。年度间无性系作为父、母本及自交的花期同步指数均有极显著差异, 2014年各无性系的花期同步指数在整体水平均高于2013年,但自交指数在年度间无显著差异。相关分析表明,雌球花越多的无性系的球果数越多;而雌球花花期持续时间越长的无性系座果率越高;不同年度的雌球花盛花期和花期的持续时间均与千粒质量指标呈显著或极显著正相关。【结论】浙江姥山林场马尾松二代无性系种子园雌、雄球花的花期具有较好的同步性,无性系间没有出现花期不遇现象。无性系交配组合的雌球花可授粉期和雄球花的散粉期影响了种子园无性系的种实品质及座果率。连续2年的观测表明无性系间花期整体同步性水平存在差异,且这种差异与二代种子园无性系的亲本遗传背景有关。各无性系分别作为父、母本时,表现出无性系作为父本时的散粉期整体的同步性要高于作为母本时的可授粉期的同步性,无性系作为父本和母本时花期同步指数呈负相关,且种子园内存在1/3无性系具有高于异交平均水平的自交可能性,是马尾松二代种子园管理和无性系再选择应综合考虑的因素。     

我国松树种子园开花习性研究概述

对国内松树种子园开花物候、雌雄球花产量及其空间分布规律、花粉密度与飞散规律、球花产量与生长性状间的关系等方面的研究结果进行了综述.并对今后的发展提出了展望.     

油松无性系种子园人工辅助授粉试验报告

在油松无性系种子园初果期,花粉量不能满足自然授粉需要的情况下,进行人工辅助授粉可使好果率提高15.9%,出籽率提高0.8%,即在种子园球果产量相同的情况下,可使种子产量提高26.7%,另外辅助授粉还可提高球果的饱粒率,降低败育粒和空粒的比率,使种子的播种品质有所提高。     

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。     

油松无性系开花物候特点的研究

在河南卢氏油松种子园对46个无性系结实初期和结实盛期开花物候作了观测，结果表明，一般雌球花可授期比授期比雄球花散粉期来得早，持续时间长，散粉期含在可授期内，散粉期和可授期同步性较好；在不同年份开花始期前后相差2-3d，开花始期早晚与当年≥10℃的活动积温有关，由于受花期温度和降雨等因素的影响，不同年份花期长短可相差10d左右，但不存在花期不遇，不同无性系在开花物候上存在很大差异，但在不同年份各无性系在始花时间上序次则相对稳定，无性系内分株间开花物候仅有1-2d的差异，位于树冠北向的雌雄球花各日期在开花频率上与其它3个方位有较大差异。始花期推后1d左右，此外，还研究了开花物候对同步指数的影响，以及不同物候类型授粉效率的差异。     

影响长白松无性系搜集圃初期球果,种子产量因子的探讨

１４年生长白松无性系搜集圃的球果、种子产量较低。本文从不同长白松无性系，以及其开花物候期、无性系内植株生长优劣和进行人工授粉四个方面对其球困种子产量进行探讨后，提出了选择优良无性系，培育整齐二菌，进行集约经营和进行人工辅助授粉等三项营建优质优势高产长白松无性系种子园的具体措施。     

湿地松种子园无性系种实性状遗传与变异研究

本文研究了湿地松种子园无性系种实性状的遗传与变异。结果表明:种子园无性系的平均种子潜能(SP)为182,平均种子效率(SE)为9.9%;球果长、宽在无性系内差异不显著,其重复力分别为0.886、0.912,这说明球果长、宽主要受遗传控制,种子千粒重、种子潜能在无性系间存在显著差异;球果饱满种子数、种子效率在无性系内存在显著差异;果长、果宽、球果饱满种子数、种子效率在无性系间存在极显著差异;种子千粒重年度重复力为0.704,说明其受环境的影响较大;球果饱满种子数、种子潜能、种子效率等性状主要受遗传控制,重复力分别为0.683、0.792、0.704,且这些性状与种子园种子产量的联系更密切,选择无性系嫁接建园及遗传疏伐时应充分重视,并根据这些性状,采取有效的经营管理技术提高种子园的种子产量。     

Are Phenological Observations Sufficient to Estimate the Quality of Seed Crops from a <Emphasis Type="Italic">Eucalyptus grandis</Emphasis> Open-pollinated Seed Orchard? Consequences for Seed Collections

Reproductive phenology was observed over three years in a Eucalyptus grandis seed orchard in Madagascar to determine the impact of geographic differences of parental selections on the expected genetic composition of seed crops. Pollen flow (observed pollen cloud) was deduced from a paternity assignment based on sampling from one year’s seed production. The two approaches were used to verify whether knowledge of phenology is sufficient to predict the genetic quality of the seeds collected. Despite the high flowering level, with a constant cycle over three years, the results demonstrated wide reproductive phenological differences associated with the parents’ origin, suggesting putative pollination disequilibrium. From both observed and expected pollen clouds, the results showed preferential mating among different provenances, which has consequences for seed crop composition. Phenological observations, which can be made inexpensively, can be used to promote methods of effective seed orchard management in order to improve the genetic quality of seeds.     

Effect of flowering phenology,date of cone collection,cone-storage treatment and seed pretreatment on yield and germination of seeds from a Douglas-Fir seed orchard

The effects of reproductive phenology, date of cone harvest, cone storage and seed pretreatment on yield and germination of seeds from a Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] seed orchard were studied. Flowering phenology (early, intermediate or late) had no discernible effect on seed maturation. Higher germination and yields of filled seeds were obtained from cones collected in mid-August, approximately 2 weeks prior to cone opening, than from cones collected just as they began to open. Seeds extracted immediately following harvest germinated better than those from cones stored for 2 months. Seeds from all treatments were dormant and responded to prechilling by exhibiting increased germination rates. The implications of these findings for cone-crop management are discussed.     

Genetic variation in fruitfulness in a hinoki (Chamaecyparis obtusa Endl.) seed orchard and its impact on the maintenance of genetic diversity in seedlots

Genetic variation in seed/cone production among clones was studied in a hinoki (Chamaecyparis obtusa Endl.) seed orchard containing 25 plus-trees by analyzing the number of cones, the yield of cones and seeds of individual ramets for 5 successive years (1982 to 1986). There was significant variation among clones each year and parental contribution in the seed orchard. Specifically, in the years 1982, 1983, 1984, 1985, and 1986, 20% of the clones produced 37.2, 60.6, 36.0, 44.3, and 44.8% of the total cones, respectively. The size of the crop greatly influenced the parental balance in the resulting seed/cone crops. The product moment correlation coefficients and Spearman’s coefficients of rank correlation were small and insignificant between consecutive years, but large and highly significant between alternate years, suggesting the presence of carry-over effects in seed/cone production. The broad-sense heritability on a clone mean basis was 0.74 ± 0.15 for the number of cones, 0.72 ± 0.14 for the yield of cones, and 0.68 ± 0.13 for the yield of seeds. The corresponding heritabilities from analyses combined over all years were 0.24, 0.558, and 0.724, respectively. These results indicate that seed/cone production in hinoki is under strong genetic control. Several managerial measures are discussed that maintain the genetic diversity in seedlots used for reforestation, by reducing the variation in seed/cone production among clones and producing seed crops with equal contributions from all parents.     

马尾松种子园无性系结实量、种实性状及遗传参数的分析

马尾松(Pinusmassoniana)是我国南方重要的用材树种。80年代初在马尾松主产区建立了一批初级无性系种子园,并开展了种子园有关营建技术的研究。反映种子园无性系繁育能力的种实性状包括了球果及种子性状,是林木种子园经营管理者所关注的重要内容,它涉及到种子园的产量和种子品质等问题。国外对火炬树(P .teada)、阿勒皮红松(P .abasica)、斑克松(P .banksiana)、白云杉(Piceaglaua)、北美黄杉(Pseudosugamenziesii)等树种(Matthewsetal.,1986 ;Matzirisetal.,1998;Todhunteretal.,1981;Horh ,1984 ;Clairetal .,1991) ,研究了花粉产量…     

Variation in reproductive phenology in a Pinus patula seed orchard and risk of genetic contamination from nearby natural stands

New Forests - Genetic variation in reproductive phenology among clones in a seed orchard affects the genetic efficiency of the orchard. Our objective was to evaluate genetic variation in...     

Flowering and Airborne Pollen Occurrence in a Pinus sylvestris Seed Orchard Consisting of Northern Clones

To explain the high background pollination rate detected in earlier studies, this study investigated the flowering phenology of a Scots pine seed orchard with respect to airborne pollen occurrence during 1992 and 1993. The receptive period of the female strobili and the shedding period of the male strobili were observed visually. Airborne pollen was monitored with Rotorod traps located inside and outside the seed orchard. There was no time gap in the onset of flowering between the earliest female and male strobili in 1992. Female flowering began 3 days earlier than male flowering in 1993, and the earliest strobili were probably pollinated by pollen transported long distance from more southerly areas. The almost simultaneous peak in pollen occurrence inside the seed orchard and in surrounding pine stands indicates that the seed orchard clones are not temporally isolated from sources of contamination. However, pollen concentrations inside the seed orchard were higher than those in the surrounding stands. Therefore, flowering phenology cannot sufficiently explain the observed pollen contamination rates in this seed orchard.