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1.
R. F. Korcak 《Plant and Soil》1985,85(3):437-441
Summary Fluidized bed combustion represents a feasible technology for energy production utilizing high S fossil fuels. The process generates not only bed waste (FBM) (coal ash plus CaSO4 and unreacted CaO) but also flyash (FA). The later waste has not been evaluated for its effects on plants and soils. A greenhouse experiment, using apple seedlings, was carried out using FBM, FA and calcitic limestone applied at or up to twice the lime requirement on three soil materials. Seedling growth varied dependent upon the treatment-soil combination. Growth was reduced by 60% on the Manor soil from FA applied at twice the lime requirement and was attributed to the higher initial reactiveness of the FA compared to FBM or limestone. Leaf P, K, N, Cu and Al were not significantly affected by treatments over all soils while Ca, and N decreased and Mg varied depedent upon treatment. Soil pH was increased by all treatments. DTPA (diethylenetriaminepentaacetic acid) extractable Mn and Zn were good estimators of leaf Mn and Zn while DTPA Cu and Fe were not. 相似文献
2.
Adventitious root formation in vitro in 1-mm stem slices cut from microshoots of apple cv. Jork 9 was studied using light
and electron microscopy. When indole-3-butyric acid (IBA) had been added to the medium, starch grains accumulated during the
first 24 h of culture in cells of the cambial region and in cells in the vicinity of vascular tissue and in the primary rays.
This accumulation occurred only in the basal part of explants. After that, the nuclei in these cells were activated, and the
density of the cytoplasm and the number of cell organelles increased, whereas starch was broken down. Cambium cells started
to divide transversely and at 96 h, after several divisions, a continuous ring of isodiametric cytoplasmic cells had appeared
around the xylem near the basal cutting surface. The cells in this ring were rich in cell structures, and did not contain
large starch grains and a central vacuole. Root meristemoids regenerated from the portions of the ring that were localized
in the primary rays. From the other cells in the ring, callus developed. The meristemoids did not grow into the direction
of the epidermis as in shoots, but along the vascular bundles. After emergence from the cutting surface, the meristemoids
were transformed into small, dome-like primordia. They developed a typical root apex with root cap, root ground meristem and
tracheid connection with shoot vascular tissue.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
Effect of 1,2-benzisoxazole-3-acetic acid on adventitious shoot regeneration and in vitro rooting in apple 总被引:3,自引:0,他引:3
The effect of 1,2-benzisoxazole-3-acetic acid (BOA), compared to 1-naphthaleneacetic acid (NAA), on adventitious shoot formation
in leaf portions and compared to indolebutyric acid (IBA), on in vitro rooting in the apple (Malus domestica Borkh) cultivars McIntosh and Gala, and one rootstock, Jork 9, was investigated. BOA at 43.0 μm or 2.7 μm at NAA in combination
with 17.8 μm benzyladenine (BA), induced the highest number of explants to produce adventitious shoots in Jork 9. In Gala,
the combination of 21.5 μm BOA with 1.0 μm thidiazuron (TDZ) or with 22.0 μm BA induced the highest regeneration percentages,
58 and 54%, respectively, giving more satisfactory results than NAA (where only 42% of leaf explants exhibited shoot formation).
In McIntosh, the highest percentage of regeneration was obtained with 1.3 μm NAA and 22.0 μm BA, while 51% was the highest
response obtained with the BOA treatment. The combination of BOA with TDZ completely inhibited regeneration activity in leaf
portions of this cultivar. The shoots of all the genotypes obtained with the most morphogenetic NAA or BOA treatments were
excised, multiplied and successfully rooted and hardened. The results demonstrate that the synthetic auxin BOA is active in
inducing shoot regeneration from leaf explants of apple and that the activity of BOA in plant regeneration is genotype dependent.
When BOA was used to induce rooting in apple microcuttings, lower rooting percentages were obtained than with IBA, showing
that the effect of BOA in inducing root formation is very low and that it cannot be used routinely to replace IBA in the in
vitro rooting of microcuttings.
Received: 18 June 1998 / Revision received: 4 January 1999 / Accepted: 29 January 1999 相似文献
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Final fruit production is the result of a number of processes, over which several environmental circumstances interact. But it is often difficult to disentangle the part played by each of these factors in the final crop. The aim of this work is to evaluate the influence of the progamic phase for fruiting in the apple tree. For this purpose we track back the process that goes from flower to fruit, identifying the inflection points where the final crop is reduced. We evaluate early versus late fruit development, pollination versus non‐pollination, and the effect of the progamic phase that goes from pollination to fertilization. From flowers to fruits 15 weeks elapsed, but the final fruit set settled 8 weeks after flowering, and the main flower–fruit drop occurred 3–4 weeks after flowering. Differences between dropped fruits and those that remained in the tree emerged earlier, and the onset of fruiting started 7 days after pollination. This time was coincident with the time lapse of the progamic phase. These results show that fruiting gets established well ahead of cropping, but also that the progamic phase is the main determinant of the final fruit set in apple trees. 相似文献
9.
Andrew P. Dare Sumathi Tomes Midori Jones Tony K. McGhie David E. Stevenson Ross A. Johnson David R. Greenwood Roger P. Hellens 《The Plant journal : for cell and molecular biology》2013,74(3):398-410
We have identified in apple (Malus × domestica) three chalcone synthase (CHS) genes. In order to understand the functional redundancy of this gene family RNA interference knockout lines were generated where all three of these genes were down‐regulated. These lines had no detectable anthocyanins and radically reduced concentrations of dihydrochalcones and flavonoids. Surprisingly, down‐regulation of CHS also led to major changes in plant development, resulting in plants with shortened internode lengths, smaller leaves and a greatly reduced growth rate. Microscopic analysis revealed that these phenotypic changes extended down to the cellular level, with CHS‐silenced lines showing aberrant cellular organisation in the leaves. Fruit collected from one CHS‐silenced line was smaller than the ‘Royal Gala’ controls, lacked flavonoids in the skin and flesh and also had changes in cell morphology. Auxin transport experiments showed increased rates of auxin transport in a CHS‐silenced line compared with the ‘Royal Gala’ control. As flavonoids are well known to be key modulators of auxin transport, we hypothesise that the removal of almost all flavonoids from the plant by CHS silencing creates a vastly altered environment for auxin transport to occur and results in the observed changes in growth and development. 相似文献
10.
新疆野苹果是我国重要的野生果树资源,在栽培苹果起源研究和砧木利用方面有重要价值。本文在收集整理近年来有关新疆野苹果大量文献的基础上,从苹果砧木利用角度,就新疆野苹果对主要生物逆境、非生物逆境的抗性以及与主栽品种的嫁接亲和性进行了综述,以期为相关研究提供参考。 相似文献