共查询到19条相似文献，搜索用时 859 毫秒
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以一年生"红阳"猕猴桃嫁接苗为试材,以无遮荫覆盖为对照,研究一层膜遮荫(透光率约70%)、二层膜遮荫(透光率约45%)和三层膜遮荫(透光率约25%)对猕猴桃容器苗叶绿素含量、渗透调节物质、保护酶活性、叶绿素荧光参数及叶片细胞结构的影响。结果表明:一层、二层膜遮荫后猕猴桃苗生长健壮,主要表现为相对叶绿素含量、还原型谷胱甘肽酶(GSH)、过氧化物酶(POD)、过氧化氢酶(CAT)和超氧化物歧化酶(SOD)活性显著高于对照;丙二醛(MDA)含量显著低于对照;PSⅡ最大光化学效率(Fv/Fm)、PSⅡ潜在活性(Fv/Fo)、光化学电子传递效率(ETR)、光化学猝灭系数(qP)以及栅栏组织/海绵组织比均显著高于对照,而非光化学猝灭系数(qN)显著性低于对照;三层膜遮荫下猕猴桃苗的各项生理指标与对照无显著性差异。因此,适度遮荫可有效防止夏季强光对猕猴桃苗的损害。 相似文献
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不同遮荫度对观赏辣椒苗期形态和生理生化指标的影响 总被引：2，自引：1，他引：1
研究了遮荫度20%、40%、60%、80%,对照为正常光照下观赏辣椒苗期的形态和生理生化指标的变化。结果表明:在不同遮荫度下,观赏辣椒的株高、株幅、叶长、叶宽表现出显著或极显著差异,其中在遮荫度20%下,GS3-1和GS2品种的株高和株幅达到最大值;在遮荫度40%下,其叶长、叶宽达到最大值。随遮荫度增大,观赏辣椒和P101体内MDA含量呈现上升的趋势;生物量增量呈现完全降低趋势;叶绿素相对含量和POD酶活性呈现逐渐降低趋势;可溶性蛋白表现出不规律的变化。遮荫改变了观赏辣椒苗期的形态和生物量增量,同时生理生化指标也相应发生了变化,观赏辣椒在苗期对光环境具有一定的适应能力,严重遮荫不利于其后期正常生长发育。 相似文献
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黄瓜响应低温胁迫的生理及分子机制研究进展 总被引：2，自引：0，他引：2
低温是影响黄瓜生长发育的重要环境因子。本文首先从黄瓜的膜系统、保护酶系统、激素含量、渗透调节物质和光合特性等方面综述了国内外近年来关于黄瓜响应低温胁迫的生理生化基础及植物响应低温信号的分子转导机制的研究现状,然后从黄瓜的耐低温遗传规律和基因定位、耐低温相关基因的功能研究等方面论述了黄瓜耐低温胁迫的分子机制,并总结了提高黄瓜低温耐受性的有效措施,旨在为解决生产中的黄瓜低温冷害问题提供重要的理论依据。 相似文献
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以茶梅‘小玫瑰’、冠盖藤、聚花过路黄和兰花三七4种园林植物1年生苗为试验材料,遮荫处理4个月,研究不同遮荫处理(全光照、遮荫65%、遮荫80%和遮荫95%)对植株生长及生理生化指标的影响,并用隶属函数分析法对4种植物的耐荫性进行了综合评价。结果表明:茶梅‘小玫瑰’、兰花三七在4种遮荫处理下,4个月后株高均有所增长,但冠幅表现为在遮荫65%和遮荫80%条件下,均有一定的增长,在全光照和遮荫95%条件下为先增长后减小的趋势,冠盖藤覆盖度也出现此现象,聚花过路黄在4种条件下均能生长良好。随着遮荫度增加,4种植物叶片的叶绿素a、b以及叶绿素a+b含量均为先增后减,均高于对照,叶绿素a/b值总体呈现降低趋势;可溶性蛋白质含量均有所降低;相对电导率表现为冠盖藤为先降后增,其余3种植物均为增加的趋势;MDA含量表现为兰花三七为先降后增,其余3种植物均为降低的趋势;POD活性和SOD活性表现为先增后降,除冠盖藤SOD活性表现为先降后增。隶属函数分析法综合评价4种植物的耐荫性,耐荫性顺序为兰花三七>聚花过路黄>冠盖藤>茶梅‘小玫瑰’。 相似文献
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以萝卜芽苗菜为材料,在其生长期外施不同浓度EDTA,初步探讨了EDTA对铅胁迫下萝卜芽苗菜部分生理生化特性的影响.结果表明:在300 mg/L铅胁迫浓度下萝卜芽苗菜的膜透性明显增大,过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性、可溶性蛋白含量明显下降.随着外施EDTA浓度的增加,萝卜芽苗菜的膜透性先下降后升高,过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性、可溶性蛋白含量先升后降.就供试材料而言,在一定浓度范围内的EDTA对铅胁迫萝卜芽苗菜的伤害效应有缓解作用,其中以0.75 μmol/L EDTA处理效果最为明显. 相似文献
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以大花飞燕草幼苗为试材,研究了干旱胁迫及复水条件对大花飞燕草幼苗膜脂过氧化和保护酶活性、渗透物质等生理特性的影响。结果表明:随干旱胁迫时间的延长,细胞膜透性和丙二醛(MDA)含量不断增加,在干旱胁迫的第20天,细胞膜透性和MDA含量均达到最大,此时植物受害严重。叶片中脯氨酸(Pro)含量迅速增加,复水后又开始下降,膜透性得到了一定的恢复。可溶性蛋白质含量不断下降。复水后,植物的可溶性蛋白质含量有所升高。当胁迫20d时,其体内可溶性蛋白质含量最低。随着时间的推移,干旱胁迫下植株体内的过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性均呈先上升后下降的趋势,复水后,POD、SOD活性呈缓慢升高的趋势。第10天时,POD、SOD活性达到最大值,说明此时植物自身有较高的清除活性氧的能力。 相似文献
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以红叶小檗、水蜡、金叶女贞、连翘、北京丁香、小叶黄杨6种常见园林树种为试材,正常光照为对照,测定分析不同程度的遮荫方式对每种树种的苗高、新梢生长情况、叶绿素、叶片含水量、叶面积等生长生理指标的影响.结果表明:不同的园林树木在遮荫环境下生长和生理反应各不相同,其中在无遮荫条件下红叶小檗、小叶黄杨、北京丁香、金叶女贞的各项生长指标最高,水蜡在双层遮荫条件下生长指标最高,连翘的生长指标遮荫组和对照组无明显差异.遮荫条件对连翘、水蜡的生理指标无显著影响,红叶小檗、小叶黄杨、金叶女贞在遮荫条件下生理指标相比对照组较为显著,北京丁香的生理指标单层遮荫组相比对照组显著,双层遮荫组不显著. 相似文献
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从洛阳地区挖掘了做药用植物栽培的款冬,根据其生态习性,种植于不同的园林绿地环境中以观察其在洛阳的园林应用效果。结果表明:1 a基本恢复生长,2 a开花结果,观赏特性保持良好。款冬喜半阴半阳,通过不同的配置,发现款冬适应园林绿地中的多种种植环境,是具有良好开发利用前景的园林绿化观赏地被植物。 相似文献
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Urban green spaces are an important component of the urban ecosystem of cities as they provide a range of ecosystem services that contribute to sustainability and livability of urban areas. The extent to which such services are provided is influenced by limitations on biological processes that underpin such ecosystem services. A poorly understood limitation in the urban environment is the effects of shade created by buildings on the adequacy of photosynthetically active radiation (PAR) for plant growth. We examined the effects of building shade in high-density, high-rise residential estates in Singapore on the level and distribution of PAR, and how PAR might in turn be correlated with growth of plants in community green spaces nested within these estates. Our estimates showed that high-rise and high-density buildings reduced daily PAR by almost 50% when compared to fully exposed conditions. The reduced PAR levels were correlated with lower vegetative and reproductive growth of several species of shrubs, and increased slenderness of two tree species. The shade environment created by buildings was differentiated from shade under vegetation canopies by longer periods of high instantaneous PAR during a diurnal cycle. There was also evidence of higher red to far-red ratio in the spectral composition of PAR. We suggest that an understanding of the spatial and temporal characteristics of PAR is necessary for appropriate selection of plants, particularly to match daily PAR received on site to daily light integral requirements of plants for improved delivery of ecosystem services. 相似文献
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Viburnum opulus L. ‘Nanum’ was grown under 100, 70, 53 and 37% of available sun. Heavy shade and full sun decreased foliar N content, while P and K contents were constant at all light levels. Plants receiving 70 and 53% of available sunlight grew significantly larger than plants in full sunlight or heavy shade. Heavy shade also decreased cold hardiness in late winter. 相似文献
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遮荫处理对金钱松幼苗生理特性的影响 总被引：1，自引：0，他引：1
以2、3a生金钱松小苗为试材,研究不同程度的遮荫(0%、30%、50%、70%、95%)对金钱松小苗生理特性的影响。结果表明:随着遮荫程度的加强,叶绿素a、叶绿素b、叶绿素(a+b)在遮荫70%处理上升到最大值,在遮荫95%处理下降,a/b整体呈现下降趋势,POD、叶片相对含水量、可溶性蛋白、脯氨酸含量均有不同程度的升高,得出金钱松幼苗在遮荫30%～50%对其生长良好,在遮荫95%处理下生长受到抑制。 相似文献
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J. I. Fahl M. L. C. Carelli J. Vega A. C. Magalhães 《The Journal of Horticultural Science and Biotechnology》2013,88(1):161-169
SummaryShoot growth attributes, leaf anatomical changes and net photosynthetic rates were determined in young coffee plants fertilized at high and low levels and subjected to shade or full sunlight. High nitrogen supply increased plant height irrespective of the light level imposed during growth, and promoted a larger leaf area in plants of the shade treatment. Specific leaf weight was 15% higher in plants grown in full sunlight than in shaded plants, at both nitrogen levels. The number of leaves developed on the orthotropic stem increased significantly under full irradiance and high nitrogen availability. Leaves were 11% thicker ih unshaded plants than in shaded ones, because of the increased size of the palisade and spongy parenchyma tissues. More thylakoids per granum and more grana per chloroplast were observed in shade-grown plants, mainly in those given high nitrogen treatment. Total nitrogen content expressed on a leaf-area basis was higher in sun plants supplemented with nitrogen, whereas chlorophyll a and b and protochlorophyll contents increased in shade-grown plants. Net photosynthetic rate in high nitrogen plants reached 7.19 µmol CO2 m?2 s?1 in the full irradiance treatment, and 5.46 µmol CO2 m?2 s?1 in shaded plants. Maximum net photosynthetic rates in the low nitrogen plants were 5.28 and 4.90 µmol CO2 m?2 s?1 in sun and shade plants, respectively. Increased photosynthetic light saturation was observed in high irradiance plants (628 µmol m?2 s?1) relative to shade plants (359 µmol m?2 s?1) in the high nitrogen treatment. The same pattern was observed in low nitrogen plants. The apparent quantum yield of shade acclimated plants was 14% higher than in those grown in full sunlight. Our results indicate that coffee may be classified as a facultative shade species, exhibiting features of sun adapted plants coupled with shade acclimation attributes, this fairly high adaptive capacity to shade:sun transition being strongly influenced by the level of nitrogen nutrition given to the plants. 相似文献
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研究了不同遮阴条件下滇山茶（Camellia reticulata Lindl.）花瓣中花青素苷组成和含量的变化。结果表明：滇山茶的花瓣中含有13种以上的花青素苷,其中主要成分矢车菊素–3–O–(2–O–β–木糖基)–β–葡萄糖苷（Cy3GX）与矢车菊素–3–O–[2–O–β–木糖基–6–O–(E)–p–香豆酰]–β–葡萄糖苷（Cy3GEpCX）的含量占总花青素苷含量的60.4% ~ 64.2%。在开花期,随着遮阴率的升高和遮阴时间的延长,花瓣中13种花青素苷的含量都同时呈现先升高后下降的变化趋势,但各组分占总花青素苷含量的百分比不变。用60% ~ 70%遮阳网遮阴,对提高滇山茶花瓣中Cy3GX、Cy3GEpCX以及总花青素苷含量的效果最明显,遮阴处理21 d时上述花青素苷含量皆达最大值。90%遮阳网遮阴,花青素苷含量低于不遮阴时的含量。在云南山茶花的种植中,根据实际环境条件适当遮阴,对增加花瓣各种花青素苷的含量,改善花色具有重要意义。 相似文献
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J. R. Kessler A. M. Armitage 《The Journal of Horticultural Science and Biotechnology》2013,88(6):849-854
Seedlings of Begonia x semperflorens-cultorum Hort. ‘Scarletta’ were grown under 0,45, or 57% of ambient light in a glass greenhouse. Shoot dry weight, lateral shoot leaf area, total leaf area, and node number decreased under increasing shade over time. Histological examination of shoot apices indicated that floral initiation occurred two to three weeks later in plants under 57% shade than those under ambient light or 45% shade. Plants under ambient light reached visible bud about five weeks before those under 57% shade and the time of floral development from visible bud to anthesis was also shorter for plants in ambient light compared with those grown under 45 and 57% shade. Staminate flower numbers on the first inflorescence increased under 45% shade compared with ambient light and 57% shade while pistillate flower numbers were unchanged. 相似文献
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以大叶芹为试验材料,根据其原生环境的特点,进行遮荫栽培。结果表明:遮荫能够降低叶片温度,但差别不明显;随着遮荫程度的增加,气孔阻力增加;适度遮荫使细胞间CO2浓度减少;不同遮荫处理下蒸腾速率的趋势基本相同,但各处理在同一时间蒸腾速率的值不同;遮荫可以使净光合速率增加;遮荫使叶绿素含量也显著高于对照。 相似文献