共查询到20条相似文献，搜索用时 203 毫秒
1.
根据群众习惯,油菜一向采用实生繁殖,由于其异花授粉性及环境的影响,亲子代间、子代单株间,表型性状均出现多种变异,在表型选优基础上,进行主要经济性的遗传鉴定,是预估良种在生产上遗 相似文献
2.
3.
4.
利用５年生１３９个马尾松天然林优树自由授粉家系的测定材料,研究生长性状和雌、雄球花量的遗传变异,估算家系和家系内个体的育种值。该子代测定林是实生种子园的一部分。研究结果高、径生长和雌、雄球花量在家系间存在着极显著的差异,多数家系的生长最都大于当地的试验对照。性状的家系遗传力较高,而单株遗传力较低、雌、雄球花量所受的遗传控制与生长性状相近,遗传相关分析表明,开花性状似独立于生长性状。利用最佳线性预测 相似文献
5.
6.
利用５年生１３９个马尾松天然林优树自由授粉家系的测定材料,研究生长性状和雌、雄球花量的遗传变异,估算家系和家系内个体的育种值。该子代测定林是实生种子园的一部分。研究结果表明,高、径生长和雌、雄球花量在家系间存在着极显著的差异,多数家系的生长量都大于当地的试验对照。性状的家系遗传力较高,而单株遗传力较低。雌、雄球花量所受的遗传控制与生长性状相近。遗传相关分析表明,开花性状似独立于生长性状。利用最佳线性预测给出了估算家系亲本和家系内个体育种值的指数方程,两者的预测精度分别为０．６５２２和０．４２１５。根据指数方程估算家系和家系内个体的育种值,以作为实生种子园疏伐去劣的依据。最后就实生种子园的疏伐去劣原则进行了论述。 相似文献
7.
研究了百山祖冷杉(Abies beshanzuensis)分布区适生立地表层土壤养分及其与百山祖冷杉枝叶营养元素含量的相关性.结果表明,土壤pH5.11～6.42,土壤有机质含量、全氮含量、速效磷含量、速效钾含量分别为119.075 0g/kg、2.196 2g/kg、15.016 3mg/kg、136.215 2mg/kg;百山祖冷杉对土壤N、P、K富集能力均较高,而对微量元素富集能力较弱,且枝部和针叶均未检出Na元素;较高的土壤N含量,可相应显著提高百山祖冷杉叶N、K含量水平,较高的土壤P含量,则显著抑制百山祖冷杉叶对K和枝对N的积累水平,较高的土壤Cu含量显著降低了Cu元素在叶器官中的积累,而显著增加了枝条中Cu和Zn的积累水平,较高的土壤Fe含量则显著促进了针叶中Fe元素和枝中Fe、Mn元素的积累水平. 相似文献
8.
白榆子代测验的十年结果 总被引：5，自引：1，他引：5
本文以河南省选出的白榆优树为材料,平行地进行的半同胞子代和无性系子代测验的结果,表明白榆优树半同胞子代间差异不显著,而且与对照也不显著,这可能是白榆生长条件复杂,选优准确性低和异花授粉又引起入选优树基因重组造成。同一批材料的无性系测验揭示优树的基因型间有极显著差异,因而对异花授粉树种进行无性系选择的育种效果要比现行的以混合选择为依据的种子园途径成本低,选种效率高。无性系测验的决选林龄也可以比家系选择提前。 相似文献
9.
湿地松种子园无性系开花习性遗传变异的研究 总被引：3，自引：1，他引：2
湿地松种子园无性系花期长短和早晚因无性系而异,且与花前的积温,特别是当年1-3月的积温,花期内温、湿度等主要气候因子有关。多数无性系散粉期比授粉期短而集中,且相互重叠。少数无性系花期部分不遇或完全不遇。不同无性系雌雄花的着生量极不平衡,1/4的无性系对子代的贡献率为45％以上,而另外的1/4则仅为15％左右。不同年度着花量也不一样,雄球花呈增长趋势,雌球花则明显受结实周期的影响。胸径生产对着花量影响较大,适当增加胸径生长对提高种子园着花量是行之有效的。 相似文献
10.
11.
Rong H. Ho 《Forest Ecology and Management》1991,40(3-4):261-269
Potted 3-year-old grafts of black spruce [Picea mariana (Mill.) B.S.P.] at different stages of lateral shoot elongation were sprayed with different concentrations of gibberellin A4/7 for a total of six weeks in a heated greenhouse to enhance seed-cone production. Grafts sprayed during the period of lateral shoot elongation produced significantly more seed cones but not pollen cones, while spraying initiated after the elongation did not promote any cone production. Increasing gibberellin did not increase production, but increased graft mortality when spraying was done during the period of rapid shoot elongation. Cone production was highest and mortality lowest with 200 mg l−1 gibberellin A4/7 spraying that was initiated in the middle of rapid shoot elongation. In a second experiment, potted 5-year-old grafts with or without root pruning were placed either outdoors or in a heated greenhouse during the period of lateral shoot elongation. Heat-treatment during the period of late show shoot elongation had a positive effect on pollen- and seed-cone production in 5-year-old grafts without root-pruning. A combination of heat-treatment and root-pruning appeared to have an adverse effect on cone production. Pollen viability was not affected by the treatments. 相似文献
12.
《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
13.
《Forest Ecology and Management》1988,23(1):39-46
White spruce [Picea glauca (Moench) Voss] grafts growing in a seed orchard were sprayed with gibberellin A4/7 (GA4/7), either at different periods of time during the growing season or in different concentrations, for a 3-year period. Whole-tree spraying in May through July 1983 significantly increased cone production in 1984, while spraying in June through August of the same year was not effective. The best treatment in branch spraying was at the highest concentration (800 mg/L GA4/7). The spray was effective in a good, but not a poor, crop year. Vegetative budburst occurred in the first half of May and shoot elongation ended in late June. Needle primordia in a newly formed bud were not discernible until the end of June. Application of GA4/7 during the period of bud scale initiation and shoot elongation, and before needle primordial initiation, could have influenced the course of bud differentiation to increase the formation of reproductive buds. 相似文献
14.
15.
16.
以红松种子园中的生长形状相对一致的嫁接母树为试验材料,研究不同树冠修剪和切根方法对母树雌雄球花分化数量的影响。结果表明,不同处理均对母树雌雄球花分化数量有显著的促进作用,其中:剪去树冠第一层轮枝和顶梢部分,在第二层轮枝中选留3个生长健壮且分布均匀的侧枝,其余侧枝全部剪除的处理方法,对雌球花分化数量的增加作用最为明显,差异达到极显著水平;切断试验母树3/4环形沟中的根系和试验母树环形沟中全部根系的处理方法,对雌雄球花分化数量的增加作用最为明显,差异达到极显著水平。 相似文献
17.
Large numbers of cones (strobili) were induced in a 10-year-old plot of mature grafts of Picea sitchensis (Bong.) Carr. All trees injected with 20 mg GA(4 + 7) in June initiated female and male cones in the same year. This treatment increased the number of female cones per plant 12-fold above the controls, more than doubling the percentage of cones that were female. Complete bark-ringing (done in May of the previous year) showed an additive effect with GA on the number of female cones formed, but a negative interaction on the number of male cones induced. Ringing promoted male cone production most when used alone. Treatments, singly or combined, also increased the proportion of cones that were lateral, compared with the preponderance of terminal male cones in the controls. The effects were apparently not directly associated with alterations in vegetative vigor, although these occurred causing a reduction in the proportion of buds containing vegetative shoots the following year. The clones differed in most characteristics, but both sparse and prolific clones were induced to reproductive activity. Viable seed yields per tree, and notional production from seed-orchards were enhanced almost 10-fold by GA injection, and about 4-fold by bark-ringing and GA + bark-ringing. 相似文献
18.
The influence of injecting 38-year-old Larix occidentalis with gibberellin A4/7 (GA4/7) on seed and pollen cone production was studied in western Montana, U.S.A. Two natural stands thinned to several spacings in 1961 were chosen. The two widest spacings were used. In 1991, 60 trees selected for study at each site were randomly divided into two groups of similar DBH, half as controls and half injected in June 1991 with a solution of GA4/7 in ethyl alcohol. The volume injected was adjusted to the DBH of each tree (60 mg per 5 cm diameter). In June 1994, half the trees treated with GA4/7 in 1991 and half the untreated trees were injected with GA4/7 in the same manner as before. In 1992 and 1995, seed cone production increased on GA4/7-treated trees compared to the controls. Pollen cone production was significantly increased by GA4/7 treatment but only at one site. Delayed effects of GA4/7 on seed cone production was not evident in subsequent years after treatment. Foliar and shoot damage on treated trees was attributed to GA4/7 treatment but most trees recovered completely the following year. Finally, GA4/7 treatment did not affect cone length, potential seed per cone or filled seed per cone. 相似文献
19.
对所选择的12个红豆树优良单株进行苗期生长测定,结果表明:优良单株的子代生长效应能明显显示其母本的优良性状特征;其中,优良单株依次为优株4、优株3、优株6、优株8、优株12、优株10、优株2、优株7、优株5,增长率分别为62.1%、34.7%、30.7%、24.2%、20.7%、19.3%、16.9%、8.5%、7.0%.红豆树优良单株子代的地径、苗高、幅度宽度、枝角等性状的广义遗传力分别为8.9%、20.0%、34.9%、13.9%. 相似文献
20.
Keith E. Woeste 《林业研究》2011,22(3):353-359
Three kinds of plant growth regulators, gibberellinA 4/7 (GA 4/7 ), 6-benzylaminopurine (BA), and chlormequat chloride (CCC), were evaluated for their ability to promote strobilus and cone production in a Chinese pine (Pinus tabuliformis Carr.) clonal seed orchard. Treatments (0, 250, 500, or 1000 mg L -1 ) were applied during three periods (June- July, July-August and August-September) in 2005. Of the three plant growth regulators, GA 4/7 was the best for promoting flower and cone production. Trees sprayed... 相似文献