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51.
52.
Morphology and rooting of shoots developing in response to decapitation and pruning of Caribbean pine 总被引:2,自引:0,他引:2
The effects of decapitation at various levels, combined with heavy pruning of remaining branches, were examined for Caribbean pine. This treatment stimulated the development of shoots with long primary needles at all levels in the crown of trees aged one, four and eight years. Although a significant positive relationship between primary needle length and rooting was demonstrated, the very juvenile appearance of these shoots was not a reliable guide to rooting. There was an over-riding effect on rooting of the ortet age × level in crown × decapitation height treatment. Decapitated trees provided shoots of higher rooting capacity than intact trees for the one and four, but not the eight year old trees. Shoots developing in the lower crown in response to decapitation and heavy pruning of four year old trees displayed a high level of rooting-equivalent to that of shoots from the decapitated and pruned one year old trees. 相似文献
53.
S. Hauser 《Agroforestry Systems》1993,24(2):111-121
Root observations were carried out on a typic Paleudult in the humid forest zone of south eastern Nigeria in an alley cropping trial usingDactyladenia (Acioa) barteri andSenna (Cassia) siamea as hedgerow trees and the interrow space planted to maize/cassava intercrop. Rooting depth ofD. barteri andS. siamea exceeded 1.6 m. Lateral root propagation ofS. siamea was 15 m, and ofD. barteri was 5 m from the hedgerows. The whole no-tree control plot was within the range of roots of the adjacent hedgerows. Rooting density and depth ofS. siamea in the no-tree control plot was generally higher than of cassava.S. siamea and cassava root density were inversely correlated. Assuming radial symmetry of root propagation, water and nutrients were available from an area 6.1 and 2.3 times larger than the allocated plot size ofS. siamea andD. barteri, respectively. Data obtained in alley cropping trials, not considering lateral root propagation, can be invalidated through exploitation of the no-tree control treatment and nutrient acquisition by hedgerow species from a larger area than allocated, thus underestimating and overestimating the performances of the respective treatments. Possible alternative measures for avoiding root interference are discussed but no good solution can be given. 相似文献
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Adventitious rooting in shoot cuttings of neem (Azadirachta indica) and karanj (Pongamia pinnata) was investigated in different seasons. The influence of auxins and B-vitamins (neem only) was evaluated. Maximum rhizogenesis coincided with the emergence of new sprouts i.e. February (neem) and March (karanj). Considering both rooting percentage and root biomass, IBA was the most effective auxin tested. Compared to auxin free controls, IBA (1000 ppm in neem and 800 ppm in karanj) significantly increased adventitious rooting percentage (80 to 100 % respectively), the numbers of roots and root biomass for both species. In neem, B-vitamin treatment yielded 40–50% rooting for cuttings. This was significantly greater than rooting for controls but equivalent to IAA treatments. In neem, some of the cuttings treated with 2000–3000 ppm IBA had well developed root systems without any sprouts. In karanj, all auxin treatments promoted sprouting. The level of total soluble sugars in the rooting zone of neem and karanj was higher in non-rooted than rooted cuttings. 相似文献
57.
榕属树种的扦插生根试验 总被引:1,自引:1,他引:1
对黄叶榕,花叶垂叶榕,垂叶榕和黄叶垂叶榕4年榕属树种进行扦插生根试验,结果表明;扦插所用的材料,处理的方法和扦插时间不同,其平均生根率也不同。这4个树种的扦插最好在秋季进行,选用经黄化处理的当年生半木质化枝条作插穗,其基部蘸生根粉后扦插,可提高生根率,缩短生根时间。 相似文献
58.
通过单因素试验设计研究了不同类别促生根剂(W)对枸杞插穗生根率高低、生根条数多少的影响;还通过正交试验设计L8(27)方法来研究了促生根剂浓度(E)、母株采穗部位(C)、不同木质化插条(P)及插条下部径粗(Y)对枸杞扦插生根率高低、生根数多少的影响。结果证明:使用促生根剂ABT-1#(W2)来处理插条时扦插效果最好,平均生根率高达89.7%、生根数多达11.2条;采用糊状的浓度为700ppm(E2)促生根剂ABT-1#来粘母株下部(C2)所剪下部径粗为0.8~1.2mm(Y1)的未木质化的插条(P1)时,即采用E2C2Y1P1组合时对枸杞扦插效果最佳,平均生根率多达95.3%、生根数高达15.6条。 相似文献
59.
Nothofagus leoni has a restricted distribution in Chilean forests. This work determines suitable culture conditions forin vitro multiplication and rooting through shoots obtained from seedlings. Broadleaved Tree Medium was suitable for shoot multiplication.
A medium with a pulse of 0.55 μM BA in the first subculture and two subcultures on BA-free medium resulted in a multiplication
rate at day 63 of × 5.7, without callus growth or shoot neoformation. Rooted shoots of good quality (number and length of
roots without callus growth) were obtained with 1.23 μM IBA (91.4% of rooting). The first roots appeared at day 11, reaching
a higher speed of rooting at day 15. 相似文献
60.
ABT生根粉新型试剂对中药材生长效果影响 总被引:2,自引:0,他引:2
以ABT生根粉新型试剂6号,7号,10号对金银花,甜味菊,土人参,黄栀子4种中药材生长效果的试验以及采用不同的施用方法对其生长效果的试验。 相似文献