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Four separate experiments were carried out in greenhouse conditions from spring of 2001 to summer of 2003. The aim of this research was to study the effect of factors such as leaf age, salt type and concentration, number of foliar applications, and the nutritional status on the efficiency of foliar applications of potassium (K) in olive plants. In all experiments, mist-rooted ‘Picual’ olive plants growing in 2 L pots containing perlite were fertigated with a complete nutrient solution containing 0.05 mM or 2.5 mM potassium chloride (KCl). In one experiment, plants received two foliar applications with five concentrations of KCl (0%, 2%, 4%, 6%, or 8%) at 63 and 84 days after transplanting. Foliar KCl applications at 2% or 4% increased shoot lengths and the K content of plants fertigated with 0.05 mM KCl (poor K nourished), while foliar KCl application did not have any influence on the growth or K content of plants fertigated with 2.5 mM KCl (normal K nourished). When the number of foliar applications was increased, the results showed that two foliar applications were enough to increase leaf K concentration in olive plants above the sufficiency level. Leaf age could influence the efficiency of foliar K application. Leaf K concentration were higher in young leaves than in mature ones. All K-salts studied as foliar sprays [KCl, potassium sulfate (K2SO4), potassium nitrate (KNO3), potassium carbonate (K2CO3), and potassium phosphate (KH2PO4)] were effective in increasing leaf K concentration. The results obtained in the present study indicate that foliar applications of K effectively increase K content in K-deficient olive plants, and that foliar applications might be more effective on young leaves. Two foliar applications of 4% KCl or the equivalent for other salts are enough to increase leaf K concentration. 相似文献
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通过GC-MS分析,确定了油橄榄(Olea europaea)树叶挥发物的主要成分为:β-石竹烯(14.29%)、α-芹子烯(13.13%)、β-芹子烯(10.15%)、α-石竹烯(6.60%)、橙花叔醇(6.72%)、3-己烯-1-醇(5.03%)和苯乙醛(5.61%)等。利用"Y"型双向选择嗅觉仪进行的室内趋向反应试验发现,芳樟醇、β-石竹烯、α-石竹烯、α-芹子烯和β-芹子烯对陈齿爪鳃金龟(Holotrichia cheni)具有显著的引诱作用;3-己烯-1-醇和壬醛化合物对陈齿爪鳃金龟雌虫具有明显的驱避作用,苯乙醛具有明显的引诱活性;橙花叔醇对雌虫具有驱避作用,而对雄虫则表现引诱活性。 相似文献
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Shinpei Ohki Yuuta Kasahara Yukiharu Sato Ko Wakabayashi Yoshiko Miyamoto Johannes W Vonk 《Pest management science》1999,55(6):674-675
Nitrification inhibitory activity of halomethyl-1,3,5-triazines was determined by measuring the inhibitory activities on ammonia-oxidation to nitrate (NO3−-N) in an upland soil and on ammonia-oxidation to nitrite (NO2−-N) by Nitrosomonas europaea ATCC 25978 (ATCC) and Nitrosomonas sp TK 794 (TK). Within the chlorinated trimethyl-1,3,5-triazines, those bearing at least one trichloromethyl group inhibited nitrification more strongly, both in soil and in cell suspension of ATCC, than other mono- or dichlorinated methyl-1,3,5-triazines. Introduction of an amino group to 2,4,6-tris(trichloromethyl)-1,3,5-triazine gave 10- and 100-fold increases of nitrification inhibitory activity in soil and ATCC cell culture, respectively. Within the trihalomethyl-1,3,5-triazines, those having tribromomethyl group(s) exhibited rather weaker nitrification inhibition in soil than the corresponding trichloromethyl-1,3,5-triazines, although they showed a strong inhibition in cell suspension. Ammonium oxidation in ATCC was inhibited more strongly than that in TK. In QSAR studies, the optimum log P values were calculated as c 4.30. By using this value it will become possible to design highly active trichloromethyl-1,3,5-triazine nitrification inhibitors. 相似文献
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盐角草(Salicornia europaea)为藜科(Chenopodiaceae)盐角草属(Salieornia)植物。本研究以吐鲁番艾丁湖盐角草种子为对象,通过野外采集,室内试验的方法,对种子形态、散布方式、变温萌发特征进行研究。结果表明,盐角草存在3种类型的种子(简称A型、B型和C型);A型种子主要分布于穗状花序的中央花位上,有翅状附属物,直径为(2.496±0.264) mm,种子容易从母体上脱离,可随风传播到较远的距离,具有相对较宽范围的萌发温度,萌发率高(超过80%);B型种子分布于穗状花序的边花位上,有翅状附属物但较为短小,直径为(1.709±0.181) mm,种子较易从母体上脱离,脱落后散布于母体附近或可随风传播至较远的距离,萌发率和萌发速度略低于A型种子;C型种子随机分布于植株中下部穗状花序的边花位上,直径仅为(1.115±0.085) mm;C型种子不易脱落,只能散落在母体底部或是附近,萌发率低(低于10%),种子休眠率高。 相似文献
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以昆明市海口林场油橄榄种植园51年生油橄榄为研究对象,采用水肥调控处理,对比分析始花期、盛花期、幼果期、熟果期叶片的叶绿素相对含量、净光合速率、蒸腾速率、气孔导度、水分利用效率的差异,建立净光合速率与果实产量及品质的关联性。结果表明:水肥调控显著提高了油橄榄物候期的叶绿素相对含量、净光合速率和水分利用效率,显著提高了始花期和幼果期的气孔导度,但对油橄榄生理期光合指标的变化趋势影响较小。油橄榄物候期的叶绿素相对含量、净光合速率呈直线上升的趋势,气孔导度呈下降升高再降低的波状曲线,蒸腾速率先升高后降低的趋势,水分利用效率先降低后升高的趋势。此外,油橄榄物候期的净光合速率与饱和脂肪酸呈显著正相关,与亚油酸含量呈显著负相关,而与果实产量、含油率、不饱和脂肪酸的相关性均不显著。由此可见,水肥调控能够提高油橄榄的光合特性,但不影响油橄榄物候期光合趋势,合理的水肥管理有益于促进油橄榄果实饱和脂肪酸的积累提升。 相似文献