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1.
《Scandinavian Journal of Forest Research》2012,27(1-4):60-67
Two experiments (Expt 1, Expt 2) with supplemental mass pollination (SMP) were carried out in a seed orchard of Pinus sylvestris L. in order to assess the biological and operational prospects for SMP. The success of the SMP was studied by means of allozyme markers. In Expt 1 the pollen mix was applied very close to each female strobilus. The estimated success rates for treatments varied between 66% and 84%. When supplemental pollination was done at peak receptivity, one single pollination was enough to obtain high success rates. In Expt 2 the pollen mix was dusted over clusters of receptive strobili on whole‐trees. The estimated success rates for treatments varied between 10% and 23%. The success rates improved when the trees were pollinated on more than one occasion per day during the receptive period. The overall conclusion is that SMP is practical for P. sylvestris seed orchards. 相似文献
2.
思茅松无性系种子园雌雄球花分布特性及人工辅助授粉的研究 总被引：1，自引：0，他引：1
在云南省林业科学院普文试验林场思茅松种子园开展了 16个无性系的雌雄球花空间分布特性及人工辅助授粉的研究 ,结果表明 :各无性系间雌雄球花数量及雌雄比均差异极显著 ,存在偏雌偏雄的变异 ;雌雄球花数量的空间分布存在一定的规律性 ,在垂直方向上 ,79%以上的雌球花分布于树冠的中上部 ,80 %的雄花分布在树冠的中下部 ;在水平方向 ,东、西、南、北 4个方位球花数量的分布基本一致。种子园的落花现象比较严重 ,且不同无性系的落花率不同 ;人工辅助授粉有助于雌球花的保存和座果率的提高 相似文献
3.
《Scandinavian Journal of Forest Research》2012,27(2):111-117
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. 相似文献
4.
《Scandinavian Journal of Forest Research》2012,27(8):715-723
This study examined the differences in mating system between indoor versus outdoor Scots pine (Pinus sylvestris L.) seed orchard using DNA markers. By analyzing the paternities in seed crops from isolation tents, we found a significant reduction in contamination rate, from 23% in the outdoor open blocks to 0% inside the tents. Increase in selfing rate and a decrease in genetic diversity in the crops were also observed inside the tents. These undesirable effects can be mitigated to some extent by the supplementation of extra pollen genotypes, e.g. selfing rate decreased from 14.4% to 6.6% and the effective number of fathers increased from 6 to 11.4 in the tents without and with supplemental mass pollination, respectively. Our study showed that tent isolation may become an effective rescuer for seed orchards where pollen contamination is severe. 相似文献
5.
《Scandinavian Journal of Forest Research》2012,27(1-4):41-49
The joint levels of outcrossing and contamination in two young northern Swedish Scots pine (Pinus sylvestris L.) seed orchards were studied with the aid of allozyme markers. High levels of contamination (21–36%) were estimated and were attributed to the observed low within orchard pollen production. Outcrossing rate estimates were high (0.957–0.961), though they departed significantly from complete outcrossing (t= 1.0) in spite of the observed high contamination levels. These results confirmed reported relationships between outcrossing and contamination levels in open‐pollinated seed orchards. It was concluded that a crop management option relying on supplemental mass‐pollination would be effective in reducing both contamination and inbreeding levels. 相似文献
6.
《Scandinavian Journal of Forest Research》2012,27(4):280-289
Abstract Female fertility is the basis for the output of seeds from clonal orchards and its variation is of major interest for the economics and biology of seed orchards, especially for the efficiency and diversity of seed orchard crops. Assessments of female fertility variation in 10 mature (>15 years old) seed orchards of Scots pine (Pinus sylvestris L.) were evaluated and compared. Depending on the individual orchard, fertility variation for each clone was assessed in slightly different ways, e.g. number of strobili, cones, seeds or litre of cones per ramet. Assessments in five of the orchards were made over consecutive years. The main result was that the clonal variation in mean female fertility per surviving ramet was lower than expected from the literature; the Kang–Lindgren sibling coefficient (Ψ) within individual years averaged 1.35. The variation between ramets within clones and years was of similar magnitude as that between clones. Clone by year interactions were noticeable, but were slightly lower than the variation between as well as that within clones in individual years. There was considerable variation in the variance components between years. The limited variation in female fertility indicated that it should not be a selection criterion when selecting clones for a seed orchard. Furthermore, it will not result in large differences between clones in seed set or large reductions in gene diversity in productive Scots pine seed orchards. 相似文献
7.
《Scandinavian Journal of Forest Research》2012,27(6):533-539
Abstract Reducing the generation turnover increases the genetic gain in a breeding programme. Topgrafting, new genetic material being grafted into the crown of ramets of reproductive mature trees, can deliver this aim since it is able to induce strobili production in young material of conifers. To this end, I studied the effect of scion age (seedlings of 4–6 years from seed) on topgraft vitality/survival, and female and male strobili production in Pinus sylvestris (L.) over 5 years. The seedlings' growing environment prior to topgrafting had a significant impact on topgraft vitality, with more vital topgrafts obtained from potted seedlings than from seedlings grown in raised nursery beds. However, the growth environment had no clear effect on female or male strobili production. In the second year, after grafting up to 76% of the topgrafted seedlings had female strobili. Vitality increased with age of the seedling from which the scions were collected, but differences in both female and male strobili production were only marginal. The position of the topgraft within the interstock crown influenced both vitality and strobili production, with higher vitality and greater male strobili production in low positions and greater female strobili production in high positions. Based on these results, breeders should perform topgrafting as soon as the seedlings have enough scions for planned crossing activities. 相似文献
8.
Vinod Prasad KHANDURI 《中国林学(英文版)》2012,14(1):20-29
Male components of the reproduction process in Pinus roxburghii were investigated for their variation in time and space as well as pollination,viz.flowering phenology,pollen production variability and pollen dispersal,for five successive years at two different locations (at the lower and higher elevations).The study reveals that elevation and the hour of the day are the main determinants of anthesis and microsporangium dehiscence,because both are related to temperature and humidity.The receptivity of ovulate cone strobili or female strobili occurred earlier at the lower elevation than at the higher elevation,with a longer receptivity period in the latter case.The phenology of male and female cones varied significantly between years and elevations.The determinations of pollen yield considered various sources of variability,i.e.,the number of pollen strobili per branch,strobili per tree,microsporangia per tree and pollen grains per tree.Each of these parameters revealed significant year-to-year and elevation effects.Year-to-year variation in the production of pollen cone and pollen grains with mass production after a three-year period revealed a three-year cycle of masting in pollen production in P.roxburghii.The pollen dispersal decreased quickly with distance from the pollen source.As a consequence,a distance of 600 m was proposed as a minimum to prevent contamination by pollen in the management of seed orchards.The results ultimately suggest that the ample production of pollen grains per tree along with flowering synchrony and long dispersal of pollen grains results in homogeneity in large populations. 相似文献
9.
华山松种子园无性系开花习性研究 总被引：2，自引：0，他引：2
云南楚雄华山松种子园的无性系,其雌球花着生在树冠外围枝条,而雄球花主要着生在树冠的内膛枝条。在水平方向上,雌球花多着生在树冠南部,雄球花的分布比较均衡;在垂直方向上,雄球花基本分布在树冠的中下部,雌球花则分布在树冠的中上部。大多数无性系的雄球花散粉期比雌花可授期早2~4 d;不同无性系间的雌雄花期具有一定的同步性。各无性系间雌、雄球花数量存在极显著差异,且有明显的偏雌或偏雄特性。雄球花量与无性系生长性状间存在显著正相关,雌球花量与树体生长相关性不显著。 相似文献
10.
Pollination dynamics in a Douglas-fir seed orchard as revealed by pedigree reconstruction 总被引：1，自引：0，他引：1
Ben Sk Lai Tomas Funda Cherdsak Liewlaksaneeyanawin Jaroslav Klápště Annette Van Niejenhuis Cathy Cook Michael U. Stoehr Jack Woods Yousry A. El-Kassaby 《Annals of Forest Science》2010,67(8):808-808
- ? Pollination dynamics was studied in a Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seed orchard using 8 nuclear microsatellite markers and pedigree reconstruction.
- ? The seed orchard consisted of 49 parents (clones). Cone-crop management included bloom delay and supplemental mass pollination (SMP) using 12 internal and 4 external pollen donors.
- ? A random sample of 801 bulk seeds was genotyped for both haploid megagametophyte and corresponding diploid embryo.
- ? Using the parental population’s multilocus genotypes, full pedigree reconstruction generated all the information needed to estimate the maternal, paternal, and parental reproductive success, selfing, pollen contamination, and pollination success of the 4 external pollen donors.
- ? Maternal, paternal, and parental reproductive success varied with 80% of gametes being produced by 23, 45, and 37% of the orchard’s parents, respectively, resulting in a drastically reduced effective population size as compared to the census number (14 vs. 53).
- ? Selfing, pollen contamination, and aggregate SMP success (internal and external) were estimated to be 15.2, 10.4, and 15.0%, respectively.
- ? Full pedigree reconstruction was effective in unraveling the orchard’s pollination dynamics and both female and male reproductive success.
11.
12.
《Scandinavian Journal of Forest Research》2012,27(1-4):513-520
The proportion of background pollen grains in the seed crops of two Pinus sylvestris seed orchards in Central Finland was estimated with the aid of multilocus allozyme markers. The orchards studied were more than 30 years old and in full pollen production. For the bulked seed crops of the seed orchard with southern clones the estimated average of background pollination over four years was 26%. There were statistically significant differences between years. No significant heterogeneity in the degree of background pollination between clones was found. Among single ramets there was significant heterogeneity in the estimated contamination rates, but the variation was not related to position in the orchard. For the seed orchard with northern clones the bulked seed crop was studied only for one year and the level of background pollination was found to be 33 %. These estimates are fairly high, but lower than for many other orchards. Background pollination at this level will cause losses in expected genetic gains. Part of the seeds from northern orchards will not be adapted to the intended area of use. 相似文献
13.
Supplemental mass pollination (SMP) success in a grafted lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) seed orchard in southern British Columbia was studied by employing four chloroplast DNA (cpDNA) markers to determine
fertilization success of 10 pollen parents. SMP was conducted operationally with a bulked pollen mix twice during peak receptivity
in the seed orchard. Fertilization success of the 10 SMP parents averaged 16% greater than for wind-pollinated controls in
a different section of the orchard. SMP also increased the uniformity of the male contribution in treated seeds. 相似文献
14.
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。 相似文献
15.
A. R. Griffin Tran Duc Vuong J. L. Harbard C. Y. Wong C. Brooker R. E. Vaillancourt 《New Forests》2010,40(2):131-142
Acacia mangium is a major plantation species for the pulp and paper industry in south-east Asia and there are a number of active breeding
programs. The species is predominantly outcrossing, but with a demonstrated capacity to set selfed seed where outcross pollen
is limited, with consequent inbreeding depression in the progeny. Current controlled pollination methods therefore include
a time-consuming emasculation step. We used microsatellite genotyping of seedlings to determine the consequences of outcross
pollination with and without emasculation. Only 1 of 3 mother trees set a small amount (5%) of selfed seed. Using whole inflorescences
from the male parent as the pollen applicator rather than sieved pollen reduced outcross contamination rates from 19.1 to
8.7% and substantially increased worker productivity. Application of sugar solution to the female flowers immediately prior
to pollination increased yield of sound seeds per spike. Additional improvements to the pollination protocols are discussed. 相似文献
16.
高世代种子园营建研究的进展 总被引：12，自引：0，他引：12
作者综述了国际林木育种界近十多年就高世代种子园组建理论提出的第一代种子园发展有所不同的新见解，以及在若干重要树种改良项目中设计和采用的方法。其内容包括各种育种群体的优缺点评价，高世代种子园的类别，组成材料的来源和选择方法，种子园的组成成分和设计原则等。 相似文献
17.
Evaluation of seed production in a first-generation seed orchard of Chinese pine(Pinus tabuliformis)
《林业研究》2016,(5)
We evaluated seed production in a first-generation orchard of Chinese pine(Pinus tabuliformis) during the crucial transition period from first generation to advanced generations.Clones varied significantly in all traits related to seed production.Repeatability of these traits ranged from 0 to 0.96.Seed production per ramet(SPPR),seed producing index(SPI),the number of relative female strobili(RFS),the number of scales,and the number of ineffective scales had comparatively high repeatability at 0.86,0.87,0.89,0.96,and 0.91,respectively.Correlation analysis showed that SPPR was greatly influenced by RFS and by the number of full seeds per cone.Finally,we showed that SPI was the best predictor of the seed-producing ability of clones.Our findings will assist seed orchard managers in effectively predicting and improving seed production of Chinese pine seed orchards. 相似文献
18.
We evaluated seed production in a first-generation orchard of Chinese pine (Pinus tabuliformis) during the crucial transition period from first generation to advanced generations. Clones varied significantly in all traits related to seed production. Repeatability of these traits ranged from 0 to 0.96. Seed production per ramet (SPPR), seed producing index (SPI), the number of relative female strobili (RFS), the number of scales, and the number of ineffective scales had comparatively high repeatability at 0.86, 0.87, 0.89, 0.96, and 0.91, respectively. Correlation analysis showed that SPPR was greatly influenced by RFS and by the number of full seeds per cone. Finally, we showed that SPI was the best predictor of the seed-producing ability of clones. Our findings will assist seed orchard managers in effectively predicting and improving seed production of Chinese pine seed orchards. 相似文献
19.
英德火炬松改良种子园无性系开花的时空变化 总被引：1，自引：1，他引：1
对英德火炬松改良种子园建园无性系的开花习性进行了观察，发现大部分无性系雌、雄花发育良好。无性系开花时间大约在3月4～26日，大多数无性系雌花在3月7—8日开始开放，少数在3月4～6日开始开放，雄花大多数在3月9～10日开始开放。总体上雌花比雄花早2～3d开放，早1～2d结束。全园雌花盛花期为3月8～17日，雄花盛花期为3月12～19日，雌、雄花盛花期有一个星期的时间相遇，自然条件下可保证充分授粉。种子园嫁接后第2年到第3年，90％以上的无性系开花，平均开花株率略高于70％；从第3年到第4年，100％的无性系开花，开花株率接近95％。说明嫁接后第3～4年，是种子园进入盛产的关键时期，也是实施人工控制授粉的有利时期。 相似文献