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1.
Throughout the development of plants, certain biotic and abiotic phenomena can occur which reduce not only the photosynthetic area, but also the growth, depending on the stage of plant development. Responses by plants to defoliation depend on species, the timing of agricultural practices and the intensity level of defoliation. An experiment was carried out in Tunja, Colombia under greenhouse conditions, in order to evaluate the tolerance of faba bean plants (Vicia faba) to partial defoliation. Every week material was removed along each newly emerged leaflet to simulate 50% defoliation. Another group was grown with the entire leaf area to function as a control. As a result of partial defoliation, the specific leaf area, absolute growth rate, relative growth rate and total biomass were reduced, but the leaf weight ratio was increased. In addition, the pattern of dry matter partitioning was altered so that the amount of biomass accumulated was reduced in the roots, but increased in the leaves. Additionally, the partially defoliated plants showed the ability to partly restore the removed leaf area. In this way it could be inferred that the plants of Vicia faba present a moderate capacity to tolerate early defoliation during the vegetative phase.  相似文献   

2.
Gesunde Pflanzen - Humic acid comprises the major part of humic substances and the most important component of soil organic matter (humus) that increases crop yield and quality. This research aimed...  相似文献   

3.
Gesunde Pflanzen - High salinity in soil is probably one of the most significant abiotic factors limiting plant/crop growth and development in arid and semi-arid regions. The objective of this...  相似文献   

4.
对罗布泊人工生态示范区中20种主要引种植物的叶片生理生化指标进行了测定,运用相关性分析、主成分分析和聚类分析等方法分析其抗旱及耐高温能力。结果表明:(1)在罗布泊人工生态示范区的正常灌溉制度下,示范区内引种植物的光合色素和游离脯氨酸含量处于较高水平,且两者之间具有极显著相关性。(2)主成分分析将被测指标用4个主成分来表示,分别为反映植物叶片光合作用能力、植物叶片酶活性、植物的耐旱性和植物叶片内有机溶剂含量的综合指标。(3)聚类分析将引种植物分为4类:第Ⅰ类为生长状况一般的罗布麻(Apocynum venetum L.)、沙拐枣(Calligonum mongolicum Turcz.)等植物;第Ⅱ类是生长状况较好的黑果枸杞(Lycium barabrum L.);第Ⅲ类是作为优势物种的滨藜(Atriplex patens Iljin.)和苦马豆(Sphaerophysa salsula DC.);第Ⅳ类是长势优良的沙枣(Elaeagnus angustifolia L.)。  相似文献   

5.
黑果枸杞幼苗对干旱胁迫的生理响应   总被引:7,自引:0,他引:7  
以黑果枸杞(Lycium ruthenicum Murr.)幼苗为试验材料,采用称重控水的方法,设置4个水分处理水平(对照CK、轻度胁迫D1、中度胁迫D2、重度胁迫D3),研究黑果枸杞幼苗对不同程度干旱胁迫的生理生化响应。结果显示:① 随着干旱胁迫的加剧,黑果枸杞幼苗株高、基径生长量、生物量积累和叶重比在轻度胁迫下升高,中、重度胁迫下降低;根重比、根冠比在轻、中度胁迫下升高,重度胁迫下降低。② 随着胁迫时间的延长,各处理组脯氨酸(Pro)、可溶性糖含量逐渐升高,可溶性蛋白含量先降后升;丙二醛(MDA)含量先增后减再逐渐增加。③ 随胁迫时间的延长,各处理组超氧化物歧化酶(SOD)活性逐渐升高,过氧化物酶(POD)、过氧化氢酶(CAT)活性呈先升后降的趋势。综合分析认为,干旱胁迫下,黑果枸杞幼苗通过调整生长和生物量分配,减少地上部分水分散失,增加根系物质的积累,以吸收更多的水分,利用渗透调节物的积累来改变细胞渗透势,以便减少胞内水分流失。同时,通过提高保护酶活性来减弱膜脂过氧化对自身的伤害,表现出较强的耐旱性。  相似文献   

6.
不同硼肥叶面喷施对油菜产量的影响   总被引:4,自引:0,他引:4  
油菜是喜硼作物,对硼极敏感.在缺硼土壤和潜在性缺硼的土壤中种植的油菜,其根、茎、叶、花、蕾、果都不能正常发育,且对硼的吸收量随生育进程而增加,叶面喷施硼肥是一种简便易行、投资少、见效快、收益大的施肥方式,既能增加农作物的产量、又能改善其品质.但现在硼肥种类繁多,其剂型,含量也有很大差异,在施用中存在很大的盲目性、施用效果不很理想.为增加油菜产量,本试验通过不同种类的硼肥在恩施州农科院进行了油菜叶面喷施试验,从中筛选适合恩施自治州油菜叶面喷施的硼肥品种,对提高油菜的产量和品质,增加农民的经济收入具有重要的意义.  相似文献   

7.
试验设正常灌水处理和干旱胁迫处理,讨论春玉米叶片的光合生理参数对土壤水分的阈值响应并进行生产力分级。结果表明:正常灌水处理的叶片光合速率(Pn)、蒸腾速率(Tr)和气孔导度(Gs)呈单峰曲线变化,胞间CO2浓度(Ci)和气孔限制值(Ls)对水分变化具有相反的响应变化。干旱胁迫处理下叶片的Pn、Tr在进行控水后明显下降,灌浆以前Pn下降主要是由气孔限制引起的。随着水分胁迫的加剧,光合结构受损,Pn下降,主要受非气孔因素限制。短期干旱胁迫会适当降低玉米的水分利用效率(WUE),但是下降程度不显著,WUE能达到中等水平。长期严重的水分胁迫后,WUE下降明显,与正常灌水处理相比差异极显著。以光合生理参数为指标对玉米土壤水分有效性及生产力进行分级与评价,确定当36.8%<土壤相对湿度(RWC)<42.7%时为低产低效水;42.7%相似文献   

8.
干旱胁迫对紫穗槐幼苗生理生化特性的影响   总被引:7,自引:0,他引:7  
为揭示紫穗槐幼苗在干旱胁迫下的生理生态特性和适应性,以盆栽当年生紫穗槐幼苗为材料,通过人为控制土壤含水量,研究干旱胁迫对其生理生化指标的影响.结果表明:随着干旱胁迫程度的加剧,幼苗的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)逐渐下降,水分饱和亏缺(WSD)、水分利用效率(WUE)、超氧化物歧化酶(SOD)活...  相似文献   

9.
10.
Arsenic is a non-essential and toxic heavy metal, which can cause physiological disorder in plants. The present study was undertaken to examine the possible roles of sodium nitroprusside (SNP, a donor of NO) in protection against oxidative damage due to arsenic (As) toxicity in faba bean (Vicia faba L.) plants. In this study, we measured physiochemical parameters (photosynthetic pigments, lipid peroxidation, endogenous hormones, minerals and phenolic contents) in faba bean plants exposed to AS (100, 200 and 400 µM) alone or combined with NO (100 µM). The results showed that application of all concentrations of arsenic (100, 200 and 400 µM) induced decrease on growth parameters, seed yield, photosynthetic pigments, phytohormones, minerals contents (N3?, P3?, K+, Ca2+?and Mg2+) as compared to control plants but increased lipid peroxidation, Na?+ and total phenolic compounds fraction. Foliar application of 100 µM NO reversed the inhibition induced by As treatment. In addition, arsenic was undetected in harvested seeds at all applied concentrations of arsenic. Therefore, it could be concluded that NO might account for the alleviating effect of As stress on Vicia faba plants.  相似文献   

11.
用0.15%、0.25%、0.35%的NaCl溶液分别对3份耐盐性不同的野生黄花苜蓿材料和中苜1号苜蓿(对照)的幼苗进行处理,通过测定其束缚水含量、自由水含量、组织水含量、束缚水/自由水、电导率、游离脯氨酸含量、可溶性糖含量、丙二醛含量研究黄花苜蓿种质材料的耐盐生理特性。结果表明:黄花苜蓿和紫花苜蓿对盐胁迫的生理响应有相同的变化规律,各项生理指标都与二者的耐盐性相关;灰色关联分析显示,各生理指标与耐盐性关联度大小依次为束缚水>束缚水/自由水>游离脯氨酸含量>可溶性糖含量>电导率>丙二醛含量>自由水含量。在0.35%NaCl溶液处理下,采用多项生理指标进行黄花苜蓿苗期耐盐性综合鉴定较为合理。  相似文献   

12.
ABSTRACT Components of resistance to the faba bean rust (Uromyces viciae-fabae) were studied at the histological level in seedlings and adult plants of nine faba bean (Vicia faba) lines differing in their level of resistance. Resistance of these lines was previously shown to be characterized macroscopically by an increased latent period, a decreased colony size, and a relatively decreased infection frequency. In some lines, the resistance also was associated with macroscopically visible necrosis. Histological investigations revealed few differences in spore germination and appressorium formation. Significant levels of aborted stomatal penetration by the rust fungus were found on all resistant lines. However, differences among lines were more evident once the stomata were penetrated by the infection structures. Resistance was mainly due to a restriction of haustorium formation with varying levels of early abortion of the colonies, a reduction in the number of haustoria per colony, and smaller colony size. In addition, necrosis of the host cells associated with infection hyphae was detectable in some lines from the beginning of colony development. This microscopically visible necrosis became stronger from 4 days after inoculation, resulting in a reduced growth of the colony. Differences in resistance levels were more marked in adult plants than in seedlings.  相似文献   

13.
Physiological, biochemical and molecular characteristics of Agrobacterium tumefaciens strains isolated in Italy from different host plants were analysed. Diseased plants were collected from several nurseries located in nine different regions. Out of 1293 strains isolated from 12 fruit tree and six ornamental plant species, a group of 120 strains was chosen as representative of the whole collection. The majority of the strains were biovar 2 (82.5%), agrocin 84 sensitive, and were isolated from stone fruit trees. Most of the strains identified as biovar 1 were isolated from ornamental plants and were insensitive to A. radiobacter antagonistic strain K84. Some strains that were isolated from Euonymus spp, Prunus GF 677 and Pyrus communis (pear) OHF tumours could not be allocated to any of the three Agrobacterium biovars. PCR-restriction fragment length polymorphism of the rrs gene plus the intergenic spacer was used for strain fingerprinting and characterisation. Results showed a wide genetic variability within the biovar 1 strains and homogeneity within the biovar 2 group. Biovar 2 strains from Sardinia were highly variable and differed from the biovar 2 strains isolated from the other regions of Italy.  相似文献   

14.
Ali  Nawab  Anjum  Muhammad Mehran  Khan  Gul Roz  Ali  Rovaid 《Gesunde Pflanzen》2022,74(1):41-52

Water resources are increasingly scarce, and in drought prone production systems, the capability of the plant to recover its adverse effects is important for yield stability. There is an urgent need to develop water-saving strategies for wheat production. Water stress at critical growth stages diminishes wheat production and has harmful effects on crop growth and development; however, regulated water deficit and potassium foliar application ameliorates its adverse effect up to a certain extent. Consequently, the water deficit effect at different growth stages of the crop with exogenous application of potassium was evaluated in a screenhouse experiment in a complete randomized design (CRD) having four repeats. Varieties of wheat, i.e. Lalma (drought resistant) and Pakhtunkhwa-2015 (drought susceptible), were sown. Water deficit, i.e. mild water stress (50% of water required for field capacity) and severe stress (no application of water), at different growth stages of the crop were imposed. Potassium (K) foliar spray (1%) from potassium sulfate (K2SO4) was applied at the respective stage subjected to water deficit levels. Internal water status, i.e. relative water content (RWC) and water retention capacity (WRC), were attained maximum at tillering stage under mild stress than the rest of the stages with maximum for Lalma. Conversely, water saturation deficit (WSD) and water uptake capacity (WUC) were higher under severe stress imposed at grain filling stage. Theses indices were maintained by foliar potassium application. Similarly, dry matter (DM) allocation varied for stress level imposition and translocation to other parts were improved under foliar K application. The chlorophyll indices, i.e., soil plant analysis development (SPAD) value, also decreased with the severity of water deficit. Grain yield was higher under stress imposition at grain filling stage than the rest of the stages, though severe water stress decreased yield significantly. The Potassium (K) foliar spray showed no prominent effect at grain filling. Canopy temperature increased with stress severity and was maintained under K foliar spray. Osmotic adjustment, water and turgor potential were affected by water stress and maintained with foliar K spray. Grain quality and biochemical traits of wheat were affected severely under water deficit. Potassium foliar spray was found to decrease the adverse effect of the water stress and hence maintained the quality and biochemical characters. It is concluded that application of foliar potassium decreases the adverse effects of water stress at any growth stage, minimises the stress indices drastic effect and maintains the internal water balance of the crop at different stages subjected to water deficit.

  相似文献   

15.
科尔沁沙地植物演替的生理机制   总被引:11,自引:5,他引:11  
在科尔沁沙地选择处于不同演替阶段的几种优势植物,通过测定干旱高温处理下植物形态变化和生理反应,分析讨论了植物生理抗逆性差异及其与植物演替的关系。结果表明,固定沙地上的狗尾草、白草在胁迫过程中叶片萎蔫,复水后恢复生长,其保护酶对胁迫反应快,可溶性粮、游离脯氨氨酸含量增加,是一真正的生理抗逆植物,半固定沙地上的差巴嘎蒿在胁控过程中叶发黄,但在复水后能恢复生长,这与其在胁迫过程中游离脯氨酸含量增加,维持叶渗透压减少水分过度丧失有关,半固定沙地芒苇在胁迫过程中叶干枯死亡,原因是其细胞保护酶反应迟钝,积累的氧自由基引起膜脂过氧化作用伤害了膜系统,在干旱高温胁迫下,流动沙地上的沙米和欧亚旋覆花植株迅速脱水死亡,而细胞内膜脂过氧化作用强烈引起细胞膜严重受损是其死亡的主要原因,这说明,在生境从固这一沙地向流动沙地演变过程中,不同植物抗逆性的差异在植被演替序列中起重要作用,植物演替的生理机制是从较为抗旱到较为不抗旱,从生理抗旱向躲避干旱发展。  相似文献   

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A pre-flowering foliar spray of the plant activator acibenzolar-S-methyl at 50mg/La.i. combined with a fruit dip in guazatine at 500mg/La.i. at harvest substantially decreased disease in stored melons. Major diseases occurring on rock melons and Hami melons were caused by Fusarium spp., Alternaria spp., Rhizopus spp. and Trichothecium sp. The treatment with acibenzolar-S-methyl alone was significantly effective in reduction of the disease severity in many but not all situations. The fungicide guazatine alone significantly decreased infection by Fusarium spp. but had a lesser effect on that caused by Alternaria spp. and Rhizopus spp.  相似文献   

19.
研究绿盲蝽Apolygus lucorum(Meyer-Dür)对锦葵科植物挥发物的EAG和趋向行为反应,为研发绿盲蝽引诱剂或驱避剂策略提供科学依据。田间采用动态顶空采样方法收集了7种锦葵科植物的挥发物,通过室内气相-质谱联用系统(GC-MS)进行物质鉴定及定量分析,最终测定了雌、雄绿盲蝽成虫对11种候选特征挥发物的触角电位(EAG)反应和嗅觉趋向选择行为。结果表明,7种锦葵科植物的挥发物种类和含量有较大差异,而且4种棉花品种之间的挥发物差异也很显著。棉花石远321的挥发物总量最大,其中4,8-二甲基-1,3,7-壬三烯(DMNT)含量最高,壬醛和罗勒烯其次。蜀葵的挥发物种类和含量均最少。11种候选特征挥发物均能够引起绿盲蝽雌、雄成虫EAG反应,且雄性成虫的反应值大都高于雌性成虫。其中,绿盲蝽雌、雄成虫触角对反-2-己烯酸丁酯EAG反应值最大,芳樟醇、乙酸叶醇酯、甲基庚烯酮及DMNT也能够激发绿盲蝽较大的EAG反应。在趋向行为检测中发现,DMNT及柠檬烯等对雄性成虫具有吸引作用。对雌性成虫有吸引作用的物质有γ-萜品烯、DMNT、月桂烯、α-石竹烯、罗勒烯及乙酸叶醇酯等,其中γ-萜品烯和乙酸叶醇酯对雌性成虫具有极显著吸引效果。锦葵科候选植物挥发物对绿盲蝽雌、雄虫具有不同EAG和趋向行为反应影响,候选气味化合物可以作为设计绿盲蝽引诱剂组分进行害虫防控田间实践。  相似文献   

20.
10种藜科盐生植物的抗盐生理生化特征   总被引:21,自引:7,他引:21  
对新疆荒漠地区10种藜科盐生植物的抗盐生理生化特性进行了研究.结果表明:盐生植物组功能叶中的平均脯氨酸(Pro)含量、丙二醛(MDA)含量、有机酸含量、超氧化物歧化酶(SOD)及过氧化物酶(POD)活性明显高于非盐生植物对照组,可溶性糖含量和膜透性低于对照组,肉质性与对照相比有高有低.资料表明,盐生植物与非盐生植物在许多生理生化特性上存在较明显的差异.初步分析了这些指标间的相关性及其抗盐生理意义,研究结果可为盐生植物的抗盐机理提供一定的理论参考.  相似文献   

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