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本文用水培方法研究了沙棘短茎段插穗生根的机理。结果表明,在用外源激素处理、控温控湿条件下,沙棘可以用极短的茎段(1~3芽段)插穗产生不定根,进而形成新的植物。沙棘插穗不定根形成有两种方式:一是茎段切面先产生愈伤组织,然后再分化为不定根;二是直接由茎皮层内分生组织产生不定根;且不定根产生具"茎多部位生根效应"。沙棘插穗不定根形成属于"温度敏感型",最适温度为16℃~26℃。外源激素对沙棘短茎段插穗生根表现出良好的诱导效应,而且对插穗苗的生长发育一定的影响,ABT优于GGR;"壮根素"效果优于生根粉,不仅促进发根,而且促进成熟不定根的早期结瘤。 相似文献
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不同生根处理及不同扦插基质对土沉香苗木生根的影响 总被引:1,自引:0,他引:1
通过3因素3水平正交试验设计L9(34)研究了不同生根促进剂(R)、不同生根促进剂浓度(T)及插穗不同基部下切口型(Y)对土沉香扦插育苗生根率、生根数的影响差异,研究了不同基质(E)对土沉香扦插育苗的影响差异。结果表明:使用ABT-1#(R1)+750×10-6(T3)+双削面(Y3),即R1T3Y3组合效果最佳,平均成活率达89.1%、平均单株生根数达9.9条;4种不同基质扦插对比试验中以红壤:珍珠岩=1∶1(E4)最佳,平均生根率达到90.3%。 相似文献
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This study evaluated methods to release from suppression both short shoots on lower stems and developing buds on leaders of western larch (Larix occidentalis Nutt.) seedlings, in order to increase the number of long shoots suitable for stem-tip cuttings. Treatments included application of the cytokinin N-6-benzyladenine (BA), horizontal stem bending, and decapitation on container-grown 1.5-year-old seedling ortets. The rate of release of suppressed growth of short shoots on the basal stem segments increased from 15% to 83% after spraying with 200 ppm BA and doubled on unsprayed horizontally-bent stems. Syllepsis on the upper stems increased by 19% following decapitation and by 32% after a combination of decapitation and BA treatments. Although these treatments resulted in large increases in the numbers of long shoots available for stem cuttings, the rootability of BA-treated shoots needs assessing before use in operational programs. 相似文献
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为了探索影响勃氏甜龙竹扦插生根的因素,为其快繁提供试验依据,通过正交试验,探讨勃氏甜龙竹扦插生根的适宜条件,如杀菌剂处理时间(A)、插穗年龄(B)及不同植物生长调节剂(C)。结果表明:对勃氏甜龙竹扦插生根率影响的主次关系是C>A>B,杀菌剂处理时间和不同植物生长调节剂对勃氏甜龙竹扦插生根率影响差异均达极显著水平,以多菌灵800倍液杀菌浸泡6分钟(A2)+插穗年龄18个月(B2)+ABT1号生根促进剂(C3)组合为促进勃氏甜龙竹扦插生根率的适宜条件。人为创造适宜的外界条件有利于工厂化快繁扦插育苗。 相似文献
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以北美香柏嫩枝插穗为材料,用ABT2和GGR6处理插穗,以清水处理为对照,研究扦插生根过程中营养物质的变化。结果表明:各处理的插穗,在其生根过程中可溶性总糖含量变化趋势较为相似,在根诱导期和伸长期出现峰值。ABT2处理的插穗可溶性总糖含量较高,对照的含量相对较低,推测可溶性总糖对生根起促进作用。插穗氮含量在生根过程中整体呈下降趋势,对照的氮含量高于其他处理,可能是低氮的条件更有利于生根。C/N值的变化趋势与可溶性总糖一致。可溶性总糖、C/N值与生根率的灰色关联度分析表明,可溶性总糖和C/N值可能是调控插穗生根的主要因子,且在根诱导期和伸长期作用明显。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):27-36
Leader shoots from juvenile succulent Norway spruce seedlings were used as cuttings 11 weeks after sowing. The seedlings were grown for 6 additional weeks and then apically dominant and lateral shoots were also used as cuttings. These three cutting categories, leaders, dominants and laterals, rooted 99.4, 99.0 and 97.5 % respectively and performed differently with respect to rooting development, number of roots per cutting and response to IBA and PIBA treatments (synthetic auxins). A large individual variation in number of roots per cutting, which auxin treatments did not reduce, was present within each cutting categoty. Laterals from the three different families included in the study showed a different variation than did leaders and dominants. Generally, the juvenile succulent cuttings were easy to root. Seedlings grown at a rather high light intensity (62 W/m2) had the potential to give good rooting even without hormonal treatments. 相似文献
19.
In India, mangroves occupy 6740 km2 of which the Mahanadi delta andBhitarkanika mangrove forests of Orissa cover 191.44 km2, most of whichhas been severely overexploited. World wide concern to conserve mangrovesnecessitated propagation of mangroves to re-establish them on barren andswampy land along tidal creeks around Paradeep port of Orissa. Avicenniaofficinalis, Aegiceras corniculatum, Bruguiera parviflora, B. sexangula,Ceriops decandra, Excoecaria agallocha, Heritiera fomes, Kandelia candel,Rhizophora mucronata, Sonneratia apetala were vegetatively propagated andplanted over 10 ha of degraded salt-marshy wetlands of Mahanadi delta inpure and mixed stands depending on the intensity and the frequency of tidalinundation at the experimental site. Survival was significantly higher(80%) in S. apetala followed by A. officinalis, R. mucronata, K.candel and H. fomes (70–75%). S. apetala recorded the maximumgrowth in height (3.0 m after 2 years) whereas C. decandra showed theminimum growth (0.5 m). Growth performance was better with plants in mixedstands than the plantation with single species. This gives us hope topropagate and re-establish mangroves for conservation in scientificallymanaged plantations in a physiologically arid environment. 相似文献
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