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401.
402.
杨树ARGONAUTE基因的克隆及序列分析 总被引:1,自引:0,他引:1
作为RNA诱导沉默复合体的核心元件,Argonaute(AGO)蛋白在植物生长发育过程中发挥着重要作用。以欧美杨和美洲黑杨不定根cDNA为模板,采用RT-PCR技术分离得到PeAGO5和PdAGO5基因的cDNA克隆,测序和序列分析结果表明2个目的cDNA片段均为2809bp,基因内部含有完整的开放阅读框,可编码907个氨基酸,预测蛋白质分子量分别为102.31ku和102.34ku,理论等电点(pI)分别为9.34和9.7。所推导的2个氨基酸序列之间仅有7个差异位点,含有3个保守的结构域,DUF1785、PAZ和Piwi结构域。它们与拟南芥AtAGO5蛋白的相似性分别为64.8%和64.3%,故将其命名为PeAGO5和PdAGO5。系统进化分析发现,PeAGO5和PdAGO5,与拟南芥AtAGO1,AtAGO5和AtAGO10蛋白同属一个进化分支。此外,采用实时定量PCR技术检测PeAGO5基因在杨树硬枝插穗不定根发育过程中的表达模式,推测该基因参与不定根发育调控。 相似文献
403.
404.
为进一步选择伊犁州适生杨树无性系,采用随机区组试验,对8个杨树无性系1年生扦插苗进行苗高和地径的生长节律研究。结果表明:各无性系苗高和地径生长均为“S”形生长曲线,各无性系之间差异不显著;171、LX-1和TL-3的苗高年生长量均高于对照,分别为362.90、305.79和303.94 cm,较对照增加21.27%、2.19%和1.56%,TL-3和LX-1达到了显著水平,171达到了极显著水平;171、DX-08-8和TL-3的地径年生长量均高于对照,分别为2.26、1.93和1.92 cm,较对照增加36.90%、16.73%和16.33%,均达到极显著水平。无性系171和TL-3苗期在本地表现出较好的适应性,1年生苗年生长量均优于本地良种日本白杨。 相似文献
405.
《Scandinavian Journal of Forest Research》2012,27(1-4):293-302
Twenty sets, each consisting of a tall, a medium, and a small plant, were selected from a 2 by 2‐year‐old nursery crop. Selection differential was measured. Cutting propagation was undertaken and the subsequent clones were tested in a field experiment. Differences between groups at age 1, 2, 3, 6, 8, and 10 were calculated, and ortet/ramet regressions and age‐to‐age correlations were conducted. Selection of the tall plants gave a response of approximately 17% at age 10. Accumulated genetic gain at this age by a specified stepwise selection procedure is estimated to 36%. Step one is the early selection in the nursery, step two is a later selection amongst the early selected clones and performed after 7 years’ field testing. Ageing of clones, selection for other traits and application of the clones over a variety of sites will reduce these gains. 相似文献
406.
《Scandinavian Journal of Forest Research》2012,27(6):484-490
Abstract A field trial of cuttings and seedlings of Scots pine (Pinus sylvestris L.) was measured after 1, 2, 9 and 10 years. Growth-related and stem form characteristics of rooted cuttings were compared with those of seedlings of the same origin. The cuttings were shorter than the seedlings throughout the experiment, but the difference became smaller with age. The ranking of cuttings and seedlings by average height was already the same after one growing season regardless of the differences in planting heights of the cuttings, indicating that the genetic origin affected the height more than the initial planting height. The growth patterns of the cuttings were similar to those of the seedlings. The bole straightness and stem taper after 10 years in the field were similar in both plant types, but not stable, indicating that the use of cuttings for stem quality selection at an early age has no advantages over the use of seedlings. In conclusion, the consistent performance of cuttings compared with seedlings of the same origin indicates that performance of cuttings is a valid measure of their genetic potential and that cuttings can be used to speed up selection in breeding programmes with Scots pine. 相似文献
407.
408.
马蹄荷容器扦插育苗技术试验研究 总被引:1,自引:0,他引:1
通过设置5种不同生根促进剂浓度(Q)、4种不同生根促进剂种类(G)对马蹄荷扦插生根率、生根数的影响差异进行研究;通过设置不同木质化程度的插穗(T)、不同长度插穗(M)对马蹄荷扦插生根率、生根数的影响差异进行研究。结果表明:浓度为650×10~(-6)(Q_4)生根促进剂ABT-1#(G_3)处理插穗,对马蹄荷扦插效果最好,平均生根率达70.6%,生根数达10.7条;长度为14cm(M_3)的半木质化绿枝(T_2),对马路蹄荷扦插效果最佳,平均生根率达78.7%,生根数达12.9条。 相似文献
409.
Catherine Ky-Dembele Jules Bayala Antoine Kalinganire Fatoumata Tata Traoré Bréhima Koné Alain Olivier 《Southern Forests》2016,78(3):193-199
Pterocarpus santalinoides is a multipurpose tree species, native to Africa and South America. However, excessive pruning for fodder is jeopardising its seed production leading to poor regeneration in the Sahel region. Efficient vegetative propagation techniques may overcome this concern. To address this issue, four experiments were conducted to determine the effects of substrate (Experiment 1), cutting type (Experiments 2 and 3), genotype (Experiment 4) and auxins (Experiments 1, 2, and 4) on rooting ability in a non-mist propagating unit in Mali. Among the four tested substrates, no significant differences were found in rooting parameters, including the percentage of rooted cuttings, the number of roots and secondary roots per rooted cutting, and the length of the longest root per rooted cutting. Semi-hardwood cuttings rooted significantly better than softwood cuttings with a higher percentage of rooted cuttings (31.7?±?6.5% vs. 9.2?±?2.7%), greater number of roots (8.2?±?4.8 vs 1.5?±?0.7), greater number of secondary roots (16.7?±?4.2 vs 4.6?±?1.8) and longer root length (17.8?±?12.0?cm vs 2.3?±?1.0?cm) per rooted cutting. In addition, one-node cuttings cut below the second and third nodes, respectively, had the highest rooting success (88% and 90%, respectively) followed by cuttings cut below the fourth node (68%) and the first node (62%). Significant differences in the percentage of rooted cuttings were found among 12 randomly selected genotypes with rooting varying from 2% to 75%.The results also showed that auxin application, especially IBA, had a significant effect on rooting success, the number of roots and secondary roots per rooted cutting. Single-node cuttings, and cuttings of 10?cm length with multiple softwood and semi-hardwood nodes, can be used with or without auxin treatment for successful clonal propagation of P. santalinoides. The results of the present study indicated that P. santalinoides is amenable to clonal propagation using low-cost propagators and sand-based rooting media. 相似文献
410.
杉木无性系扦插苗产量和质量的变异与相关分析 总被引:1,自引:1,他引:0
杉木无性系扦插试验结果表明,秋季扦插平均成活率83%;比春、夏、冬季扦插平均成活率分别高53%、69%和60%,102个无性系1年生秋插苗平均成苗率81%,苗高29.5%厘米,地径4.1毫米,直立率59.2%,反映秋插苗质量的苗高、地径、直立率等性状受较强的遗传控制且遗传变异幅度较大。秋插苗直立率与成苗率、同、地径之间存在极显著的遗传正相关,根据直立率进行间接选择,入选10个无性系的成活率,成苗率 相似文献