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81.
[目的]了解欧李在成都地区的适应性。[方法]以引种欧李4号和欧李5号为材料,分别对其开花时间、花期长度、坐果率及植株的高度变化等进行观测,并对其物候期进行调查。[结果]成都地区欧李的开花时间较北方地区早,物候期较北方地区提前;欧李4号的开花期为8d,平均坐果率为19.48%,高度为44~60cm的植株坐果率较高;欧李5号的开花期为15d,平均坐果率为27.24%,最高植株与最低植株的坐果率相差11.91%;欧李5号的植株高度、开花量、最高坐果率、最低坐果率及平均坐果率等均优于欧李4号,但2品种在成都地区的生长状况均较好。[结论]欧李4号和欧李5号适宜在成都地区栽植。 相似文献
82.
梅花花朵香气成分时空动态变化的研究 总被引:7,自引:4,他引:3
为了研究梅花香气成分的时空动态变化,以‘三轮玉蝶’梅花朵为材料,采用顶空-固相微萃取与气相色谱-质谱联用技术,对5个阶段的花朵及不同花器官释放的香气成分进行了分析。结果表明:从梅花开花的5个阶段共鉴定出33种化合物,乙酸苯甲酯、丁子香酚和乙酸己酯是构成‘三轮玉蝶’梅花朵香气的重要成分。在梅花开花过程中,花香化合物释放存在4种趋势,乙酸苯甲酯呈现低—高—低的动态趋势,苯甲醛呈现高—低—高的趋势,α-蒎烯、莰烯、柠檬烯和樟脑4个单萜类化合物呈现高—低的趋势,丁子香酚呈现低—高的趋势,梅花复杂的花香调节模式致使不同开花时期的香气成分和含量产生变化。从梅花不同花器官中检测出27种化合物,不同的部位释放的化合物的种类和相对含量有很大的差异。花瓣主要释放芳香族化合物和脂肪酸衍生物,雄蕊主要释放芳香族化合物,花萼、花盘和雌蕊群释放的化合物类型较广,单萜化合物在此部位检测到。在开花的第4阶段,花萼、花盘和雌蕊群释放低含量的丁子香酚和高含量的乙酸己酯可能是引诱蜜蜂觅食的重要信号。 相似文献
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一氧化氮对采后李果实线粒体膜氧化损伤的影响 总被引:2,自引:1,他引:1
【目的】研究一氧化氮(NO)对采后李果实线粒体膜氧化伤害的影响。【方法】分别用0、10、15、30μL.L-1NO处理李果实,测定25℃贮藏13d内果实呼吸速率、活性氧(ROS)含量、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)的活性、线粒体通透性转换孔开放程度、膜电位、膜流动性、细胞色素(Cyt)c/a的变化。【结果】与对照和其它NO处理相比,15μL.L-1NO提高了果实中SOD、CAT和POD活性,有效减少了果实中氢过氧化物和超氧阴离子自由基等ROS的含量,抑制了线粒体通透性转换孔的开放,延缓了线粒体膜通透性的升高和Cytc的释放,维持了较高的膜电位。随着浓度升高,30μL.L-1NO对线粒体膜的保护作用降低。【结论】15μL.L-1NO有效减轻了ROS对李果实线粒体膜的氧化伤害,保护线粒体膜的完整性。 相似文献
85.
桃花粉活性检测和离体萌发特性的研究 总被引:2,自引:1,他引:1
果树花粉活力直接影响授粉、受精乃至座果。为了解果树品种的花粉生活力,给引种栽培和杂交育种工作创造有利条件,以桃花粉为试验材料,采用染色方法检测花粉的活性。试验结果表明,含有蓝墨水的花粉培养基,花粉萌发率可以达到64.67%,与对照相比差异不明显,因此该方法比较适合于快速检测花粉活性;固体培养基培养2个品种桃花粉,萌发率比液体培养基培养分别高25%和20%。另外温度、花粉密度、培养基中蔗糖及硼酸浓度都对花粉萌发率和花粉管长度有影响,在温度为24℃、1粒花药/100 μL、10%的蔗糖或100 mg/L的硼酸的条件下,均有利于花粉萌发和花粉管生长。 相似文献
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88.
The effect of light quality on in vitro rooting of cherry rootstock “Colt” was studied to evaluate adventitious root development, ex vitro acclimatization and plant growth performance. Adventitious rooting was dependent on the light quality to which the microcutting were exposed. Highest number of roots per microcuttings was recorded under dichromatic light (blue + red). This response could be ascribed to the control of a strong synergistic interaction between phytochromes and blue light photoreceptors. Red light was more effective on root elongation than blue light. In this response a strong synergistic interaction between phytochromes and blue light photoreceptors was suggested. The effect of light quality on the number of root/explant affected the plant during acclimation, scoring the highest level of plant survival in the blue-, red- and blue + red-exposed plantlets. The light quality effect was also observed under greenhouse culture conditions, as shown by growth parameters at the end of six months in plants growth. No specific role was observed for the photoequilibrium of phytochrome. The results reported in this work show that plantlets exposed to different light quality, during the in vitro rooting phase, retain the light quality effects in the subsequent plant acclimatization and greenhouse plant growth phase. 相似文献
89.
Canopy leaf to fruit ratio (L:F) of 6-year-old ‘Lapins’ sweet cherry trees on Gisela 5 rootstock was manipulated at the end of stage II (38 DAFB) of fruit development. While control trees showed a L:F ratio of 0.7:1 without alteration, on other trees young fruit were manually removed to yield L:F ratios of 2:1 and 3:1, respectively. All leaves and young fruit on trees were counted 30 DAFB. The effect of altering the source–sink ratio of whole trees on sweet cherry fruit quality parameters (fruit increment, fruit mass, color, total soluble solids content, contents of individual sugars and organic acids) was evaluated in the study. High leaf area to fruit (LA:F) ratios influenced significantly darkest fruit color, higher fruit mass, higher total soluble solids content and higher ratio between sugars and acids, which corresponded to better ripening stage. Contents of glucose, fructose and sorbitol, but not sucrose, sum of individual sugars, and the content of malic acid differed significantly among fruit of the different treatments. Fruit of the most advanced maturity stage (treatment 3:1) had the highest quality. Each day of improved L:F ratio counts towards better sweet cherry fruit quality. The results show that low L:F ratio influenced prolonged ripening process and delayed fruit maturity of ‘Lapins’ sweet cherry. 相似文献
90.
Effects of shading and thidiazuron + oil treatment on dormancy breaking,blooming and fruit set in apricot in a warm-winter climate 总被引:1,自引:0,他引:1
Overcoming dormancy represents one of the major limitations to fruit tree production in warm areas. High temperatures during the chilling period have a negative effect on breaking of dormancy. Shading of trees reduces the incidence of radiation and the temperature. Previous works on shading did not take into account the stage of dormancy. The aim of this work was to evaluate the effects of shading during different periods of endodormancy, in an area having relatively warm winters, and the effects of a treatment of thidiazuron ([TDZ] N-phenyl-N-1,2,3-thiodiazol-5-il-urea) and winter oil, on apricot blooming, fruit set and ripening. The study was carried out during three years which showed marked differences regarding chilling accumulation. Autumn shading did not affect blooming or harvesting. Regarding harvest date, 2–3 days of precocity were achieved by shading during endodormancy, relative to the control. The TDZ + oil treatment increased blooming percentage, made blooming more uniform and brought forward the blooming (by 7–14 days) and ripening (3–8 days) dates. However, pistil abortion percentage was strongly increased by using TDZ and winter oil when there was low chilling accumulation, which led to reduce fruit set percentage. Shading during late endodormancy produced 5 days precocity for the harvest date in the year with lower chill accumulation. Shading of trees during endodormancy and TDZ + oil treatment could be suitable for increasing precocity in warm-winter climates. Significant year-to-year variation has been shown for blooming, pistil abortion, fruit set and fruit/bud percentages. Correlations among these variables are also discussed. Under conditions of marginal chill accumulation, the distribution of chilling during autumn and winter had an important role in the overcoming of dormancy, blooming and fruit set. 相似文献