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采用疏芽、疏雄花、环剥倒贴皮等技术措施进行对比试验,结果表明:疏芽树比不疏芽的平均每一结果母枝抽生结果枝多0.6条,每一结果枝平均混合花序增加18.1%,每一混合花序上雌花簇增加8.6%;疏雄花比不疏雄花每667?平均产量提高27.4%;环剥倒贴皮比对照第2年每一结果母枝抽生结果枝多33.0%,每一结果母枝产量提高40.0%。 相似文献
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Branch scoring of ‘Rojo Brillante’ persimmon (Diospyros kaki) increased fruit size at harvest and caused a significant shift in the distribution of fruit diameters to the larger sizes, the response magnitude depending on the date of scoring. Scoring at the 75–77 growth stage of the BBCH-scale encouraged the development of fruit which grew faster, reached commercial colour, ripening and flesh softness earlier, and therefore was harvested earlier. Although fruit weight was significantly increased by scoring, the number of fruit was not modified and there was not a significant increase in yield. Fruit from trees scored at the onset of cell enlargement stage initiate ethylene production before fruit from unscored trees. Scoring did not modify following yield. 相似文献
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To investigate the climate impacts on the different components of ecosystem respiration, we combined soil efflux data from a tree-girdling experiment with eddy covariance CO2 fluxes in a Mediterranean maritime pine (Pinus pinaster) forest in Central Italy. 73 trees were stem girdled to stop the flux of photosynthates from the canopy to the roots, and weekly soil respiration surveys were carried out for one year. Heterotrophic respiration (RH) was estimated from the soil CO2 flux measured in girdled plots, and rhizosphere respiration (RAb) was calculated as the difference between respiration from controls (RS) and girdled plots (RH).Results show that the RS dynamics were clearly driven by RH (average RH/RS ratio 0.74). RH predictably responded to environmental variables, being predominantly controlled by soil water availability during the hot and dry growing season (May–October) and by soil temperature during the wetter and colder months (November–March). High RS and RH peaks were recorded after rain pulses greater than 10 mm on dry soil, indicating that large soil carbon emissions were driven by the rapid microbial oxidation of labile carbon compounds. We also observed a time-lag of one week between water pulses and RAb peaks, which might be due to the delay in the translocation of recently assimilated photosynthates from the canopy to the root system. At the ecosystem scale, total autotrophic respiration (RAt, i.e. the sum of carbon respired by the rhizosphere and aboveground biomass) amounted to 60% of ecosystem respiration. RAt was predominantly controlled by photosynthesis, and showed high temperature sensitivity (Q10) only during the wet periods. Despite the fact that the study coincided with an anomalous dry year and results might therefore not represent a general pattern, these data highlight the complex climatic control of the respiratory processes responsible for ecosystem CO2 emissions. 相似文献
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橙树枝条环剥促成花时使总核酸及RNA保持高水平,RNA/DNA比值升高,对DNA无明显影响;喷赤霉素抑成花时总核酸及RNA保持低水平,RNA/DNA比值下降。留叶促成花与去叶抑成花相对比中,去叶抑DNA合成反使RNA/DNA比值上升,对RNA无明显影响,成花茎端组织分化明显,细胞中核酸含量比不成花茎端高;辅原套(At)和周围分生区(PZ)棱酸的活化与成花的关系最密切。 相似文献
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Wi Young LeeJae Soon Lee Jae-Hyeon LeeEun Woon Noh Eung-Jun Park 《Forest Ecology and Management》2011,261(11):1957-1961
The demand for Japanese larch (Larix leptolepis) seeds has increased in Korea but their supply has been limited due to sporadic natural seed production. Among the various flower induction techniques, girdling woody stems has been recognized as a simple and efficient method to enhance seed production in a number of conifers. In this study, stem girdling was applied to 42-year-old Japanese larches, resulting in remarkable enhancement of seed cone production with no morphological changes in the seed characteristics. Metabolic alterations in needles of the girdled and the control trees were interrogated by using 23 individual metabolites including soluble sugars, polyamines and amino acids. In the girdled trees, the contents of both soluble sugars and polyamines were higher from June to July and then became similar to those in the control. The levels of amino acids were significantly increased only in August by girdling compared to the non-girdled trees. In control larch trees, the dominant amino acids were changed from Glu and Ala until July to Asp and Tyr in August. Interestingly, the concentrations of Asp-derived amino acids such as Lys, Met and Thr, were increased by girdling and they also showed significant correlations with the number of seed cones per trees, suggesting that the enhanced levels of three amino acids might positively influence on the development of seed cones in girdled larch trees. Although the role of Asp-derived amino acids on enhanced seed cone production remains unclear, the approach presented in this study might provide useful information in elucidating metabolic network modulation induced by girdling and will be further applied for enhanced seed cone production in Japanese larch trees. 相似文献
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[目的]该研究旨在探讨主干一次和二次环剥对葡萄树体营养及其分配规律的影响。[方法]以“玫瑰蜜”葡萄为试材,通过对主干进行一次和二次环剥后分析对剥痕上部的叶片、枝条和剥痕下部根系的碳氮营养、矿质营养及其分配规律的影响。[结果]环剥可显著提高剥痕上部的枝叶可溶性糖和淀粉等非结构碳含量,降低可溶性蛋白质和氮素营养含量,使碳氮比显著提高,其中一次环剥后叶的碳氮比峰值为9.04,二次环剥为5.35,而同一时期对照仅为4.89。环剥不仅显著降低了根系可溶性糖和淀粉等非结构碳含量,还显著降低了可溶性蛋白质和氮素营养含量,碳氮比也有不同程度的降低,其中一次环剥后其碳氮比的最低值仅为1.16,二次环剥为3.06,而同一时期对照为3.15。对碳氮营养的影响,一次环剥显著大于二次环剥。环剥还显著降低了叶片、枝条和根系中的磷、钾、铁、铜的含量。其中二次环剥对枝条、叶片中铁、铜元素的影响较大,且第一次采样的含量差异显著,叶片中的铁含量为75.05μg/g DW,而对照为85.29μg/g DW;枝条中的铁含量为76.45μg/g DW,铜含量为7.82μg/g DW,而对照分别为95.96μg/g DW 和10.74μg/g DW。[结论]该研究为树体营养调节和保障环剥技术在“玫瑰蜜”葡萄生产中安全有效的应用奠定基础。 相似文献
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