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The effects of sulphur dioxide (SO2) and nitrogen dioxide (NO2), singly and in combination, on the shoot and root growth of two potato cultivars sensitive to these pollutant gases were determined using rooted cuttings in controlled conditions. Plants were exposed to 0.11 ppm SO2 and/or 0.11 ppm NO2 for 24 hours a day for 7 or 14 days. Kennebec plants had significantly lower root fresh and dry weights after 7 days in the mixture treatments and lower root fresh weight in the NO2 treatment. Russet Burbank plants were more sensitive to SO2 and NO2 than Kennebec. Russet Burbank plants had significantly reduced leaf area, and leaf, stem, and root fresh and dry weights after 7 and 14 days of mixture treatment, and the leaf to root dry weight ratio was higher than in control plants. The combination treatment and SO2 alone resulted in visible injury on leaves of both cultivars. Changes in tissue water concentration, decreased specific leaf area and decreased root growth suggested that SO2 and NO2 altered plant water status and interfered with partitioning of dry matter from the leaves to other plant parts. 相似文献
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Thymus vulgaris L., known as common thyme, is a perennial subshrub native to the Mediterranean region. The use of the extracts and herb of thyme plants as antibacterial, antioxidant, natural food preservative and in cosmetic industry has increased the economic importance of this medicinal crop worldwide. Agricultural practices have an influence on growth and yield of thyme plants. Therefore, an experiment was undertaken to determine the effects of three intra-row spacing (15, 30 and 45 cm) and four harvesting times (vegetative, beginning of blooming, full blooming and fruit set) on plant growth and herbage biomass of thyme in 2007 in the research farm of Shoubak University College in the southern part of Jordan. The experiment was a split plot in randomized complete block design with four replicates. Apart from the experiment in 2007, measurements taken on the 15th of November in 2008 were treated as an independent experiment irrespective of harvesting stage. The effects of spacing were not significant for all the parameters measured in 2007. Intra-row spacing in 2008 had significant effects (P < 0.05) on plant height, canopy diameter, herbage fresh and dry weight and number of leaves on long shoots. Its effect on dry weight of shoots, fresh and dry weight of long shoots, number of long shoots, root depth, leaf area and specific leaf area was very significant (P < 0.01). Results of this study indicated that thyme plants grown using 15 cm planting space and harvested at the fruit set stage in 2007 had the highest fresh and dry weight of shoots. The highest dry weight of shoots, herbage fresh and dry weight was also obtained in 2008 in 15 cm spacing. Closer spacing resulted in significantly taller plants that exhibited higher shoot:root ratio and, therefore, plants grown using 15 cm intra-row spacing had a better use of light and accumulated more biomass compared to plants in wider spacing. The differentiation between long shoots and short shoots throughout plant development in 2007 suggests a specialization in carbon gain along different times in the growing season. Swings observed for shoot:root ratio, leaf area and specific leaf area were related to thyme growth. The decrease in specific leaf area between vegetative and full bloom stage indicated that leaves became thicker as part of an adaptive mechanism to the surrounding environment. Information obtained from growth parameters, leaf area and specific leaf area in particular, could be related to essential oil production in leaves of thyme plants. 相似文献
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《Plant Production Science》2013,16(3):155-159
SummaryA greenhouse experiment was conducted to compare root system development of two upland rice cultivars, IRAT 13 and Senshou, during recovery from drought stress and to identify the plant traits that confer drought resistance. From 62 days after sowing (62 DAS), drought stress was given for 6 d followed by rewatering for 14 d. Root length density (RLD) and root diameter (thickness) were measured at the end of the stress and rewatering periods. Control plants were well-watered throughout the study. Gultivar IRAT 13 had thicker roots and higher relative RLD (ratio of RLD in drought-stressed plants to that in control plants) than under drought stress, and significantly higher root growth recovery after rewatering cultivar Senshou. Related plant traits such as evapotranspiration (ET), leaf and stem dry weights and weight of senescent leaves (dead leaves) in IRAT 13 were significantly more favorable for drought resistance compared to Senshou. 相似文献
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选择长势稍有差异的两组糯米糍(Nuomici)荔枝树，探索测量荔枝(Litchi chinensis Sonn)树冠长势的简单和精确的方法，分别测量他们的末次秋梢枝条长度、枝条粗度、复叶数、小叶数、小叶长度、小叶宽度、叶片厚度、叶脉粗度、叶片鲜重、自然干燥叶片的重量、烘干至恒重的叶片重量等。结果表明：在两组长势稍有差异的同一个荔枝品种中，他们的枝条长度、枝条粗度、复叶数、小叶数、小叶长度、小叶宽度、叶片厚度、叶脉粗度等数据没有统计学上的显著差异，但叶片鲜重、自然干燥叶片的重量、烘干至恒重的叶片重量则差异显著。作者认为：通过测量叶片鲜重来定量判定荔枝果树树冠长势的方法是既简单又精确的办法之一。 相似文献
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早籼稻品种遗传改良进程中株型的演变特征 总被引：6，自引：1，他引：6
以不同年代育成的28个代表性早籼稻品种为材料,在同一生态条件下种植,系统研究了叶型、茎型、穗型若干株型性状的演变特征。结果表明,早籼稻品种改良进程中,上部3片功能叶均变短、变厚、变直、变挺;各节间变短、变粗,节间密度变大,尤以基部节间和穗下节间最为显著,而单位鞘重变化不显著;每穗粒数、二次枝梗数、着粒密度均变大。据此认为,早籼稻叶型改良应在保持现有叶片曲率的前提下增加叶长;茎型改良应增加基部节间的粗度和穗下节间的长度;穗型改良应增加每穗粒数和枝梗数。 相似文献
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Responses to shade and subsequent recovery of soya bean in maize-soya bean relay strip intercropping
Yushan Wu Wanzhuo Gong Feng Yang Xiaochun Wang Taiwen Yong 《Plant Production Science》2016,19(2):206-214
In relay intercropping systems, late-planted crops often grow under the shade of the canopy of early-planted tall crops and then transfer to full sunlight after the harvest of the early-planted crops. In order to know the effects of recovery growth of the late-planted soya bean in maize–soya bean relay intercropping, a field experiment was carried out to observe architectural, morphological, physiological and anatomical traits of soya bean plants related to shade and subsequent removal in intercropping before and after maize harvest, respectively. During shade period, soya bean biomass was severely reduced, and stem elongation was stimulated. Typical features of shade grown leaves were found, such as lower LMA (leaf mass per unit area), thinner thickness, higher chlorophyll content, lower chlorophyll a:b ratio. Whole-plant leaf area analysis found that soya bean increased leaf area ratio by adjusting leaf morphology rather than by dry mass allocation. After maize harvest, leaf area and leaf mass increased rapidly, contributing to compensation growth in intercropped soya bean. Meanwhile, physiological and anatomical traits of leaf went back to similar levels as grown in sole cropping. However, stem morphological traits were irreversible after removal of shade. Finally, no difference on seed weight per plant of soya bean was observed between relay intercropping and sole cropping. Based on these findings, we speculated the recovery growth might be the direct determining factor on pod formation in soya bean, and improvement on the capacity of recovery growth could increase yield of relay intercropped soya bean. 相似文献
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水稻不同叶位层物理结构与冠层反射光谱的定量研究 总被引：1，自引：0，他引：1
研究了不同土壤水分、施氮条件下水稻冠层反射光谱与冠层生长特征（叶面积指数、叶片干质量和鲜质量）的量化关系。结果表明，不同层次叶面积指数、叶片鲜质量和叶片干质量与冠层光谱的相关性大小均为：L12345>L1234>L123>L12>L1，而顶部5张叶片的面积和生物量（干、鲜质量）对冠层特征反射光谱的贡献大小顺序为：L2>L1>L3>L4>L5，顶部2张叶片对冠层光谱作用最大。发现比值指数R(760,710) 与水稻叶面积指数呈极显著线性相关；而比值指数R(1650,1100) 与水稻地上部鲜质量和干质量均呈极显著幂函数相关关系。因此，比值指数R(760,710) 和R(1650,1100) 可分别用来定量反演水稻叶面积信息和地上部生物量信息。 相似文献
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Physiology of the Potato: New Insights into Root System and Repercussions for Crop Management 总被引：2，自引：0，他引：2
K. Iwama 《Potato Research》2008,51(3-4):333-353
Potato roots are concentrated mostly in the plow layer up to 30 cm in soil depth. Some roots extend up to 100 cm depth and the total root length throughout the soil profile reaches about 10–20 km m?2 area. There are large differences in root mass (dry weight and length) in the plow layer between cultivars, breeding lines and wild relatives. The differences are generally stable across different environmental conditions, such as locations with different soil types, fertilizer rates and planting densities. Under favourable environmental conditions without severe shortage of water and nutrients, root mass differences between genotypes are related to maturity class: late genotypes continue root growth longer, and attain larger root mass and deeper rooting than early genotypes. Differences in root mass become clear at the start of flowering, much earlier than differences in shoot mass. Root mass is negatively correlated with early tuber bulking. However, root mass generally shows positive correlations with shoot mass and final tuber yield. Differences in root mass also exist amongst genotypes of the same maturity class. Using root mass in the plow layer and tuber yield as selection criteria, Konyu cultivars were bred in Japan. They showed significantly less reduction of leaf conductance and photosynthesis, leaf area and tuber yield than commercial cultivars under dry soil conditions. To assist breeding for root characters, new methods have been developed to assess the ability of roots to penetrate into hard soil layers using pots with paraffin-vaseline discs and the ability to absorb under low water potential in vitro. Physiological research on root characteristics contributed in the past, and will continue to do so in the future, to the development of new cultivars with high drought tolerance and to the improvement of irrigation practice. 相似文献
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茶树鲜叶抗坏血酸过氧化物酶活性的变化规律及测定方法 总被引：3，自引：0，他引：3
探讨茶树鲜叶抗坏血酸过氧化物酶(APX)活性的测定条件,分析不同茶树品种以及茶树鲜叶不同叶位APX活性的变化.结果表明:聚乙烯聚吡咯烷酮(PVPP)加入量约为鲜叶重的1.5倍,酶提取液pH为7.8.反应液pH为7.O,抗坏血酸(AsA)浓度为0.50 mmol/L时茶树鲜叶APX活性最高;茶树鲜叶APX活性随冷藏时间的延长呈下降趋势;福建7个主要茶树品种以福鼎大白茶的APX活性最高,铁观音的APX活性最低;茶树鲜叶不同叶位APX活性变化趋势为:芽>第一叶>第二叶>第三叶>老叶>嫩茎. 相似文献
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《Field Crops Research》2001,72(1):51-66
Pearl millet (Pennisteum americanum L.) is an essential crop in farming systems of the dry areas of the semi-arid tropics and its tillering habit is an important adaptive feature. This is the first paper in a series aiming at developing and validating a pearl millet simulation model that recognises tillers as functional entities, analogous to intercrops. The objective of this paper is to quantify the effects of total leaf number per axis (TLN), cultivar, plant density and axis number on parameters that are used to simulate potential leaf area per plant. Four cultivars with different phenology and tillering habit were grown under well-watered and well-fertilised conditions at two locations in India, covering a range of daylengths and plant densities. For selected plants, the area of fully expanded leaves was measured non-destructively. A bell-shaped function adequately described the relationship between individual leaf area and leaf position on an axis. Its shape was determined by the position (X0) and area (Y0) of the largest leaf and by the breadth and skewness of the leaf area profile curve. TLN affected all four parameters, although the association with Y0 was weak. Cultivar only affected Y0, suggesting that parameterising new cultivars is straightforward. The observed density effect confirmed that competition for light between axes started during stem elongation. The results highlighted the consistent differences between leaf area profiles of main shoots and tillers. For a high-tillering crop like pearl millet, modelling leaf area dynamics through individual leaves is justified, as this approach can potentially deal with cultivar and environmental effects on tillering. 相似文献
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高温胁迫对玉米形态、叶片结构及其产量的影响 总被引：1，自引：0，他引：1
以郑单958(ZD958)和先玉335(XY335)为试验材料,模拟增温处理,探索营养生长和生殖生长并进时期(第9片叶完全展开至抽雄期)高温处理对玉米形态、叶片结构及其产量的影响。结果表明,高温处理后ZD958和XY335的产量分别比对照降低了11.14%和25.40%。高温处理促进株高增长,促使茎粗变细,降低叶面积指数、干物质重、成熟叶片和幼嫩叶片的比叶重。随生育进程,XY335的株高、茎粗、叶面积指数、干物质重和ZD958的干物质重变化幅度逐渐增大,2个玉米品种的幼嫩叶片比叶重降低幅度均要大于成熟叶片比叶重。叶片厚度和上下表皮细胞厚度变薄,叶绿体膜结构被破坏,抑制光合作用及光合产物的输出。对高温胁迫的敏感性而言,XY335大于ZD958,ZD958成熟叶大于幼嫩叶,XY335幼嫩叶大于成熟叶。 相似文献
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Irma Bernal-Lugo Carmen Parra Margarita Portilla Cecilia B. Peña-Valdivia Ernesto Moreno 《Plant foods for human nutrition (Dordrecht, Netherlands)》1997,50(2):141-150
The characteristic of proteins, starch and pectic substances in cotyledons of two bean cultivars varying in cooking time were
determined to investigate their possible contribution to bean cooking quality. Both cultivars showed the same enthalpies of
starch gelatinization but different protein denaturation enthalpies. The proportion of hot water soluble pectins was higher
in Michigan, the cultivar with the lower cooking time, than in Ojo de Cabra, the cultivar with the higher cooking time. These
results were not due to differences in pectin methylation or in the ratio of monovalent to divalent cations in the tissue,
suggesting that in fresh beans the β-elimination reaction is not the sole or predominant route of thermal pectin degradation.
Overall, this study indicates that varietal differences in bean cooking quality may be reflections of the rate of pectin loss
during soaking/heating and that the thermal properties of starch and protein fractions seem to have a minor contribution.
Researchers involved in this study propose that in fresh beans, the thermal pectin loss results from a two step mechanism:
pectin enzymic breakdown during the bean soaking followed by thermal solubilization rather than β-elimination during the bean
heating. 相似文献
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H. J. Smit B. M. Tas† H. Z. Taweel† S. Tamminga† A. Elgersma‡ 《Grass and Forage Science》2005,60(3):297-309
Four perennial ryegrass (Lolium perenne L.) cultivars were compared for differences in herbage production, nutritive value and herbage intake of dry matter (DM) during the summers of 2002 and 2003. Two paddocks were sown with pure stands of four cultivars in a randomized block design with three replicates. Each plot was subdivided into fourteen subplots (22 m × 6 m) which were grazed by one cow during 24 h. Twelve lactating dairy cows were assigned to one cultivar for a period of 2 weeks in a 4 × 4 Latin square experimental design; the experiment lasted 8 weeks in each year. Sward structure (sward surface height, DM yield, green leaf mass, bulk density and tiller density) and morphological characteristics were measured. The ash, neutral‐detergent fibre, acid‐detergent lignin, crude protein and water‐soluble carbohydrate concentrations, and in vitro digestibility of the herbage were measured. The sward was also examined for infestation by crown rust (Puccinia coronata f. sp. lolii). Herbage intake of dairy cows was estimated using the n‐alkane technique. Cultivar differences for all sward structural characteristics were found except for bulk density and tiller density in 2003. Cultivars differed for proportions of pseudostem, stem (in 2003 only) and dead material. The chemical composition of the herbage was different among cultivars, with the water‐soluble carbohydrate concentration showing large variation (>0·35). Cultivars differed in susceptibility to crown rust. Herbage intake differed among cultivars in 2002 (>2 kg DM) but not in 2003. Herbage intake was positively associated with sward height, DM yield and green leaf mass. Canopy morphology did not affect herbage intake. Crown rust affected herbage intake negatively. It was concluded that options for breeders to select for higher intake were limited. High‐yielding cultivars and cultivars highly resistant to crown rust were positively related with a high herbage intake. 相似文献
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S. S. Deshpande S. K. Sathe D. K. Salunkhe 《Plant foods for human nutrition (Dordrecht, Netherlands)》1984,34(1):53-65
The interrelationships among certain physical and chemical properties of ten cultivars of dry beans (Phaseolus vulgaris L.) were investigated. The length/breadth ratio was similar (1.51–1.65) except for kidney beans (>2.0) and sanilac (1.37) cultivars. The breadth/thickness ratio ranged from 1.17–1.65. The 100-bean weight indicated a wide variation of 15.03–50.33 g. The density, bulk density, and porosity characteristics were within a narrow range of 1.18–1.36 g/cc, 68–75 g/100 cc, and 40.7–48.5%, respectively. Water uptake rates during the first 6 h of soaking at room temperature (21 °C) were characteristic of the cultivar. At the end of 24-h soaking, however, all cultivars had absorbed similar amounts of water (approximately 1 g/g bean). Leaching losses (g solids leached/100 g beans) had characteristic trends and ranged from 0.54 for cranberry to 3.46 for sanilac cultivars after 24-h soaking. Most correlations between selected chemical constituents and physical characteristics of the dry bean were relatively low.Journal Paper No. 2751 of Utah Agricultural Experiment Station and a contribution of Western Regional Project W-150. 相似文献
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兰属植物是市场上流行的观赏花卉,其中建兰具有极高的观赏价值。目前,因建兰叶片极易染病,导致其观赏价值大幅下降,因此,本研究对16个建兰（Cymbidium ensifolium）品种的叶片气孔和横切结构进行测定,探究叶片微观结构间的差异,以期为建兰叶片功能性状研究及病虫害防治提供参考依据。利用NIS-Elements D软件对叶片表皮气孔进行测量,观测指标包括气孔器的长轴、短轴、气孔面积和气孔密度,发现建兰的气孔主要集中在下表皮,16个品种中仅‘大青’‘锦旗’2个品种上表皮有少量的气孔分布;利用NIKON数码荧光显微镜、光学数码成像系统和NIS-Elments D软件在20倍镜下对叶片的中脉长轴、中脉短轴、上表皮厚、下表皮厚、叶片厚和叶肉厚进行观测,采用SPSS软件对实验数据进行方差分析和多重比较分析。结果表明：16个建兰品种的叶片微观结构之间存在显著差异,其中建兰‘大青’的气孔密度、中脉长轴和中脉短轴最大,分别为125.19个/mm2、439.14 μm和403.51 μm。气孔密度最小的是‘朝阳三星’‘玉女素’和‘八宝奇珍’,分别为52.70、60.48、61.54个/mm2。中脉长轴与中脉短轴最小的品种是‘十三太保’和‘大凤素’,分别为147.63 μm和125.93 μm。而‘复兴奇蝶’的叶片厚度最大,为528.29 μm,叶片厚度最小的品种是‘桃腮素’,为100.32 μm。通过对16个建兰品种叶片解剖结果的相关性分析发现,气孔面积与气孔其他参数均呈极显著正相关,叶片厚度与上表皮厚度以及叶肉厚度均呈极显著正相关,而叶肉厚度与气孔面积是研究建兰非生物胁迫的重要指标。本研究可为筛选优异的建兰种质资源、新品种选育及其非生物胁迫研究提供参考。 相似文献
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《Plant Production Science》2013,16(3):185-189
AbstractThe correlations of the reading of a portable chlorophyll meter (SPAD-502) with the chlorophyll and N contents of leaves of two faba bean (Vicia fabaL.) cultivars, Japanese (Ryousai-issun) and Egyptian (Cairo 241), were examined. The SPAD readings positively correlated (ρ<0.01) with the chlorophyll contents and the r2 values were 0.99 and 1.00 for Ryousai-issun and Cairo 241, respectively. A close linear relationship (ρ0.001) was observed between SPAD reading and total leaf N content at the pod development stage of faba bean plants with r2 = 0.88 and 0.99 for Ryousai-issun and Cairo 241, respectively. The SPAD reading was the highest in the 2nd to 4th leaves counted from the top (the youngest fully expanded leaves). The changes in leaf chlorophyll content of both cultivars from 3 weeks after transplanting to the ripening stage showed an incomplete “M” type curve. SPAD readings were significant¬ly higher in Ryousai-issun than in Cairo 241 throughout the growth season. Organic fertilizers application improved faba bean plant growth. These results suggest that the SPAD-502 chlorophyll meter can be used to measure chlorophyll and nitrogen contents of faba bean leaves for quick screening faba bean genotypes. 相似文献
20.
小贯小绿叶蝉在5个茶树品种（系）上的蜜露排泄量与茶树叶片结构比较 总被引：1，自引：0，他引：1
为明确茶树叶片组织结构与小贯小绿叶蝉抗性之间的相关性,在确定小贯小绿叶蝉不同龄期和虫态蜜露排泄量的基础上,比较研究了小贯小绿叶蝉雌成虫在不同茶树品种（系）上取食24 h后蜜露排泄量的差异,进而通过比较不同茶树品种（系）叶片的组织结构和色泽,分析了5个茶树品种（系）叶片的组织结构与茶树对小贯小绿叶蝉抗性能力强弱的关系。研究结果表明,小贯小绿叶蝉4龄若虫的蜜露排泄量显著高于1~3龄;雌、雄成虫的蜜露排泄量之间不具显著差异;取食中选10号的雌成虫蜜露排泄量显著低于取食其他品种;不同品种（系）茶树的叶面积、叶片总厚度、上表皮厚度、下表皮厚度以及色差等指标与雌成虫的蜜露排泄量之间无显著相关性,而叶片茸毛密度与雌成虫蜜露排泄量呈显著负相关,叶片茸毛长度与蜜露排泄量呈显著正相关。 相似文献