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1.
Foliar micromorphology of Hippobromus pauciflorus (L.f.) Radlk (Sapindaceae) was investigated by scanning electron microscope examination. The leaves were characterized by anisocytic stomata which were found only on the abaxial surface. The leaves have long unicellular non-glandular trichomes which were distributed over the mid rib and densely populated at the edges of the upper and lower surfaces. Crystal deposits were also observed on the abaxial surface of the leaves. Energy dispersive X-ray spectroscopy SEM of the crystals showed predominant mineral components of Na, Al, Si, K and Ca ions. These micro (Si, Na and Al) and macro (K and Ca) elements are very essential to plant growth. Their presence in the trichomes could contribute to the mechanical stability of the leaf appendages.  相似文献   

2.
不同株型玉米叶片形态结构的研究   总被引:5,自引:2,他引:5  
紧凑型玉米与平展型玉米叶片形态结构有一定差别。主要表现在紧凑型玉米叶表皮气孔数目多于平展型。上表皮多17.0%,下表皮多11.5%。紧凑型玉米叶片上、下表皮气孔密度差别比平展型小。紧凑型玉米下表皮比上表皮气孔多44%,而平展型多50%。两种株型玉米叶片维管束鞘中的叶绿体均位于细胞外方,呈半圆形排列。紧凑型玉米比平展型玉米叶片维管束鞘中叶绿体含量较多。两种株型玉米叶片中脉有一定差异,紧凑型玉米叶片中脉较宽且向叶正面凹陷较深。  相似文献   

3.
以玉米为试验材料,设置5个处理,盐胁迫下添加蚯蚓粪比例分别为0、10%、20%、40%,以不添加蚯蚓粪和NaCl溶液的处理为空白对照,分析盐胁迫下添加蚯蚓粪对玉米气孔特征和光合特性的影响。结果表明,添加蚯蚓粪能够显著增加盐胁迫下玉米叶片近轴面的气孔长度、气孔面积和气孔周长,远轴面气孔长度和气孔周长也随着蚯蚓粪的添加显著增加,玉米叶片近轴面和远轴面气孔空间分布在添加蚯蚓粪处理变得更加规则。添加蚯蚓粪处理后玉米幼苗的净光合速率、胞间二氧化碳浓度和气孔导度与盐胁迫处理相比显著升高,同时玉米幼苗的水分利用效率显著升高。添加蚯蚓粪能有效增大盐胁迫下玉米幼苗叶片的最大光化学转化效率,降低相对电导率,缓解盐胁迫对玉米的伤害。  相似文献   

4.
The aim of the present work was to study salt effect on the yield and composition of shoot essential oil (EO) and the structures responsible for its biosynthesis in Mentha pulegium L. Shoot EO was extracted by hydrodistillation and composition was determined by GC–MS method. Apical and basal leaves were taken for microscopy analyses; small fresh samples were observed directly without fixation or metallisation with environmental scanning electron microscope (ESEM) and stereomicroscope (SM). Fresh separate epidermis was used for light microscopy (LM). Salt stress enhanced EO yield by about 2.75 times and affected the percentage of menthone, which is the major compound (51%), increasing that of pulegone. Menthone, pulegone, and neomenthol constituting the monoterpene class were found to be the principal components. The anatomical study showed three types of trichomes: (i) non-glandular, multicellular, simple hairs; (ii) small, capitate glandular trichomes; (iii) and peltate glandular trichomes. In control plants, the density and size of trichomes varied with leaf side (abaxial or adaxial) and developmental stage. Salt stress results in significant modifications affecting trichome distribution and size on both sides.  相似文献   

5.
Water is becoming more and more limiting factor of sugar beet production and the productivity of the crop can be significantly improved by increased drought tolerance. It is therefore a great challenge to assess the degree of variability of anatomical and morphological traits of breeding material with respect to water use efficiency and drought, that can be used as potential markers for selection of sugar beet genotypes with better tolerance to water shortage. To achieve this, the first step is to assess the degree of genetic variability with respect to anatomical and histological features linked to water management in plants, under optimal water supply. Comparative histiological analysis of lamina and petiole was done on 12 sugar beet genotypes which previously showed divergent responses to lack of water in the field. The plants were grown in semi-controlled conditions of a glasshouse, and watered daily. Mircromorphological analyses were done to assess leaf epidermal characteristics, by both light and SEM, and lamina and petiole histological features. The measurements were used to calculate the percentage of individual tissues in relation to the thickness of the lamina, main vein area and petiole area. The general structure of sample variability was established by principal component analysis (PCA), based on correlation matrix. In majority of genotypes the ratio of the size of cells of spongy parenchyma and palisade cells in average was 80%. Low genotypic variability of the studied histological parameters of the lamina and petiole may reflect the narrow genetic base of tested breeding material. The most significant genotypic difference, considering leaf epidermal tissue, was in % of adaxial and abaxial epidermis. The highest found number of stomata per mm2 on both adaxial and abaxial epidermis was 40% higher than the lowest. During water stress, when stomata are closed, plant survival depends on the amount of water lost through the cuticle. SEM analysis of adaxial epidermis of the lamina show that cuticle varies in texture. Considering the observed genotypic variability in cuticle ornamentation and the fact that plants develop various strategies of adaptation to drought, finding genotypes with increased drought tolerance could be based on the characteristics of the cuticle and epidermis.  相似文献   

6.
以2种肉饼兜兰为试材,研究其叶片生长发育规律和解剖结构。结果表明:兜兰叶片生长动态呈现S型生长曲线,生长周期长,叶片寿命长。兜兰的叶片长度、宽度和叶面积随苗龄增大而增大,萌发新叶的间隔时间随苗龄增大而增长,新叶的发育周期随苗龄增大而增长。兜兰的表皮细胞厚,而叶肉细胞厚度低,叶片组织结构紧密度低,可能是导致兜兰虽为C_3植物但是营养生长速度慢的原因。兜兰的叶片厚、上表皮细胞巨大、角质层较厚、气孔下生型和龙骨状主叶脉发达,具有明显的旱生特点。  相似文献   

7.
Wastage of agricultural chemicals and ensuing environmental pollution is an issue, where ineffective spray deposition is a major concern with conventional pesticide application methods. Electrostatic spraying is known to be one of the most effective methods to improve leaf abaxial (underside) surface deposition, overall deposition, and distribution on the plant targets. Deposition of charged sprays on leaf abaxial and adaxial (upper) surfaces as influenced by the spray charging voltage (system), application speed (operational), target height and orientation (target) parameters was studied in the laboratory. An air-assisted electrostatic induction spray charging system attached to a moving carriage was used to apply charged spray at uniform application (ground) speeds. Spray deposition (101–71 μm NMD), determined using a fluorescent tracer technique increased with charging (0–5.5 mC kg−1) on leaf abaxial and decreased with charging on adaxial surface. The deposition was higher on abaxial (0.66–1.33 μg cm−2) at 30° below (horizontal plane) and on adaxial (0.78–1.79 μg cm−2) at 0° (horizontal) target orientation for lower (0.278 m s−1) application speed. At all target heights, abaxial deposition increased with charging voltage (0–4.0 kV) for medium application speed (0.417 m s−1) and adaxial deposition decreased with charging voltage for lower application speed (0.278 m s−1). The medium application speed with higher charging voltage was optimum for abaxial and adaxial deposition. The droplet velocity and charging voltage were the key factors for obtaining desired spray deposition on targets. All the selected factors including target orientation (O), application speed (S), target surface (L), and charging voltage (V), and their interactions except between O and S were significant at lower (0.35 m) and medium (0.65 m) target heights. All the factors and their interactions except between O and V were significant at higher (0.95 m) height. Electrostatically charged spray improved the underside (abaxial) and overall deposition. The deposition was substantially influenced by factors such as charging voltage, application speed, plant target height, and target orientation.  相似文献   

8.
In the present study, various explants of Murraya paniculata (Jack) Linn., such as cotyledons, shoots and young stems were cultured on MS medium supplemented with various concentrations of Benzyl Amino Purine (BAP) under 25 +/- 1 degree C with 16 h light and 8 h dark and also 8 h light and 16 h dark to obtain complete plant regeneration. In vitro flowering was observed from shoot explants cultured on MS supplemented with 0.5-2.0 mg L(-1) Naphthalene Acetic Acid (NAA) and also on MS basal medium under similar conditions. The leaves and flowers obtained from both in vivo and in vitro conditions were examined and compared. Morphological studies such as leaf clearing, epidermal peeling were studied using light and scanning electron microscope. Macromorphological studies of the flowers produced from in vivo and in vitro conditions were also examined. Morphologically, there were no differences between in vivo and in vitro flowers except the flowers produced from tissue culture systems were smaller in size with protruding stigmas. Differences were also found in the number of layers of palisade cells and the presence or absence of epicuticle layer of the leaves. Leaves produced from tissue culture system were smaller in size with membranous texture. Stomata were present only on the abaxial surfaces of both in vivo and in vitro leaves but the stomata were raised above the epidermis in the latter.  相似文献   

9.
ABSTRACT

Leaf erectness is an important agronomic trait for improving canopy photosynthesis in rice. It is well known that leaf inclination angle (LIA) decreases after expansion during ripening. However, the high-yielding indica cultivar ‘Takanari’ retains a greater LIA during ripening than the high-quality japonica cultivar ‘Koshihikari’. To clarify the cause of the cultivar difference in LIA, we investigated anatomical characteristics of the lamina joint of a flag leaf. We found a close linear correlation between LIA at the centre and at the base of the leaf blade in both cultivars during ripening. The length of the lamina joint increased significantly more on the adaxial side of a leaf (the margin of the collar) than on the abaxial side (the abaxial side of the central part of the collar) in ‘Koshihikari’ after leaf expansion, but there was no clear difference in ‘Takanari’. We found a close linear correlation between the ratio of lamina joint length on the adaxial to abaxial sides and LIA in ‘Koshihikari’ and ‘Takanari’ during ripening. In ‘Koshihikari’, the average length of cells on the adaxial side increased significantly after leaf expansion, with no significant increase in that on the abaxial side and no significant change in cell number on either side. In ‘Takanari’, cell length and cell number showed no significant changes on either side of the lamina joint. We conclude that the cultivar difference in LIA during ripening is caused mainly by cell elongation on the adaxial side of the lamina joint.

List of Abbreviations: k: light extinction coefficient; LIA: leaf inclination angle; QTL: quantitative trait locus  相似文献   

10.
为分析小麦不同器官表皮蜡质组分和晶体结构的差异,以表皮蜡质为绿色表型的小麦品种泰山4447和白霜状表型的济麦6097为供试材料,在抽穗期分别提取穗部、叶鞘、穗下茎、旗叶、倒二叶、倒三叶和倒四叶七个不同器官的表皮蜡质,利用气相-质谱联用(GC-MS)和气相色谱(GC-FID)对各器官表皮蜡质组分进行定性和定量分析,使用场发式扫描电子显微镜观察各器官表皮蜡质的晶体结构,并对小麦旗叶进行失水率检测。结果表明,两小麦品种各器官表皮蜡质的成分主要包含初级醇、二酮、烷烃、脂肪醛、脂肪酸、酯等脂肪族化合物。泰山4447和济麦6097的穗下茎、叶鞘和颖壳表皮蜡质中二酮的含量显著高于旗叶、倒二叶、倒三叶和倒四叶,济麦6097的旗叶、穗下茎、叶鞘和颖壳表皮蜡质中二酮的含量显著高于泰山4447各器官。扫描电镜观察表明,两个小麦品种的旗叶近轴面、倒二叶、倒三叶和倒四叶的蜡质晶体为片状结构,旗叶远轴面、穗下茎和叶鞘上的蜡质晶体呈管状结构,泰山4447的颖壳表皮蜡质中管状晶体和片状晶体共存,而济麦6097的颖壳表皮蜡质中晶体结构则完全为管状。泰山4447的旗叶水分非气孔性散失速率高于济麦6097。  相似文献   

11.
用LI—1600稳态气孔计测定16个大豆品种叶片蒸腾速率和气孔阻力的结果表明:大豆叶片背面的蒸腾速率大于腹面,植株中部叶片大于上下部叶片,花期高于结荚鼓粒期,晚熟品种高于早熟品种.  相似文献   

12.
为了解节节麦(Aegilops tauschii Coss.)不同生育期叶片表皮蜡质组成及晶体形态的变化,对节节麦叶片蜡质进行提取,利用气相色谱-质谱(GC-MS)联用仪和气相色谱-火焰离子化检测仪(GC-FID)对蜡质进行了定性和定量分析,并采用扫描电镜(SEM)对叶片表面蜡质晶体形态进行了观察。结果表明,节节麦叶表皮蜡质经GC-MS分析,共鉴定出化合物21种,主要以初级醇为主(苗期、抽穗期和灌浆期相对含量分别为85%、84%和70%),并含有少量的烷烃、醛、酮和脂肪酸;随着节节麦的生长发育,蜡质总量不断积累,烷烃含量极显著地升高,其中以C29烷烃的增加最明显,而初级醇含量显著降低,其中C26醇的相对含量降低最明显(苗期、抽穗期和灌浆期相对含量分别为80%、76%和63%),其他各类化合物组分变化不大。经扫描电镜观察,节节麦叶片近轴和远轴面的蜡质晶体形态无明显差别,苗期均为片状,抽穗期大部分仍以片状形态存在,并且蜡质晶体的密集程度比苗期稀疏,灌浆期蜡质晶体的密集程度变得更加稀疏。这些变化可能与抽穗期、灌浆期烷烃含量的增加和初级醇含量的减少有关。  相似文献   

13.
为了解不同大麦品种(系)表皮蜡质组分及结构的差异,以7个大麦品种(系)开花期的倒二叶、穗下节及穗为材料,利用GC-MS和S-4800场发射扫描电子显微镜测定不同器官表皮蜡质组分,观察其晶体结构。结果表明,大麦不同器官表皮蜡质均是由烷烃、初级醇、醛、脂肪酸、二酮等20种物质组成,不同品种及不同器官表皮蜡质组分种类无明显差异,但组分含量差异显著;同一品种(系),表面有白霜覆盖器官蜡质总量明显高于无白霜覆盖器官。穗下节表皮蜡质及穗部白霜型品种(系)表皮蜡质的二酮含量最高,穗部无白霜品种(系)(QS、FR、SYR01)表皮蜡质以烷烃和初级醇为主,二酮含量显著低于白霜型品种;叶片表皮蜡质则以初级醇为主,含量明显高于其他组分,且品种(系)间差异显著。电镜观察结果表明,参试品种(系)倒二叶近轴面和远轴面表皮蜡质晶体均呈片状结构;穗下节表皮蜡质晶体结构均呈棒状,SYR01穗下节蜡质晶体附着密度远小于其余6个穗下节有白霜覆盖品种(系)。白霜型大麦品种(系)穗部表皮蜡质完全为棒状,非白霜型品种(系)穗部表面仅有少量片状蜡质晶体或无蜡质晶体附着。  相似文献   

14.
Quantification of the effects of adjuvants on droplet behaviour on plant surfaces is needed to improve pesticide spray application efficiency for soybeans. Dispersion and evaporation of single 300-μm diameter droplets amended with each of four spray adjuvants at five concentrations were investigated for four soybean plant surfaces (abaxial and adaxial leaflet surfaces, petiole, basal stem). The four adjuvants were a crop oil concentrate (COC), a modified seed oil (MSO), a non-ionic surfactant (NIS) and an oil surfactant blend (OSB). A single-droplet generator was used to produce and deposit 300-μm diameter droplets on target surfaces under controlled environmental conditions. Adjuvants significantly increased the dispersion (or wetted area) of droplets on plant surfaces. Droplet-wetted areas increased with increased adjuvant concentrations but not in direct proportion. The average increases of wetted areas across the four soybean plant surfaces were 443, 462, 416, or 343% when the spray mixture was amended with COC, MSO, NIS or OSB at the manufacturer-recommended concentrations, respectively. Among the four surfaces, the largest wetted area was on the abaxial surface, followed by the adaxial surface, the petiole and then the basal stem. Droplet evaporation times were inversely proportional to the wetted areas. The evaporation time of 300-μm diameter droplets ranged from 36 to 142 s on the four surfaces when the spray mixture was amended with an adjuvant, whereas the water-only droplets ranged from 161 to 190 s. The results demonstrated that use of adjuvants offers great potential to improve the homogeneity of sprayed pesticides, to increase spray coverage and to reduce pesticide application rates on soybean plants. These effects could benefit farmers economically and reduce environmental contamination by pesticides.  相似文献   

15.
拟南芥生物钟双突变体lhycca1营养生长时相转变   总被引:1,自引:0,他引:1  
傅钰  王苓  龙鸿 《热带作物学报》2019,40(6):1089-1094
高等植物生长发育阶段可分为营养生长和生殖生长2个阶段,其中营养生长阶段中只有通过营养生长时相转变方可进入生殖生长阶段。营养生长时相转变(vegetative phase change,VPC)是植物从幼龄期(juvenile stage)到成熟期(adult phase)的转变,受到基因表达的调控。生物钟(circadian clock)相关基因LHY和CCA1单独作用延迟VPC的发生,这2个基因的共同作用下VPC是否受到影响尚未见报道。本研究以拟南芥(Arabidopsisthaliana)为研究对象,通过形态和茎尖分生组织(shoot apical meristem,SAM)解剖结构观察及调控因子miR156和靶基因SPL3的表达变化,分析LHY和CCA12个基因在VPC过程中的作用。结果表明:双突变体lhycca1生长周期为15d,莲座叶第5片时(第10天)出现远轴面表皮毛,此时叶基角和叶长宽比增大且茎尖分生组织凸起明显,miR156和SPL3的表达水平在植物生长发育阶段呈负相关变化。而野生型生长周期为20 d,莲座叶第6片(第15天)时才出现远轴面表皮毛、叶长宽、叶基角、SAM、miR156和SPL3的变化。这些结果说明在LHY和CCA1的共同作用下,VPC提前发生,LHY和CCA1 2个基因参与VPC的调控。  相似文献   

16.
为了解冬小麦叶片显微结构和光合特性与产量的关系,采用大田跟踪对比调查方法,对8个高产冬小麦品种的叶片显微结构、光合特征及产量性状进行分析。结果表明,小麦不同叶位叶片主要由规则环状细胞组成,各叶位叶片规则细胞的平均环数为1.7~4.5环。随叶位升高,叶肉细胞平均环数及上表皮和下表皮气孔密度均有增加的趋势。各品种旗叶叶绿素含量最大峰值出现在5月10日前后;旗叶可溶性蛋白含量变化与叶绿素含量变化相似,最大值陆续出现在5月7-20日。各品种叶片叶肉细胞平均环数和平均光合速率均以旗叶最高。但品种间光合势、叶源量的差异与叶肉细胞和叶绿素含量并不完全一致。品种间产量性状的差异主要表现在生物产量与经济系数上。生物产量与倒2叶光合势呈显著正相关,与倒3叶光合势呈极显著正相关。综上可见,光合性能好且光合产物能够有效转运进入籽粒,是小麦品种获取高产的必要特征。  相似文献   

17.
采用水培研究法,探讨钙处理对2种基因型花生苗期生物量和叶片气孔数目的影响。结果表明:供试2种花生荚果和种子性状差异显著;缺钙处理对HL和HW生物量的影响不同,缺钙处理下HW的单株叶片鲜重显著低于加钙处理下的单株叶片鲜重,而HL的单株干重显著低于加钙处理下的单株干重;缺钙处理下HL的上部叶下表皮气孔数目显著低于加钙处理下的上部叶下表皮气孔数目。  相似文献   

18.
Breeding cotton, Gossypium spp., for resistance to leafhoppers of the genus Empoasca and to sweetpotato whitefly, Bemisia tabaci (Gennadius), poses a dilemma. Glabrous (smooth-leaved) cotton plants have higher leafhopper populations but fewer whiteflies and less leaf and bract trash in mechanically harvested seedcotton than plants with pubescent leaves. In this study, both leafhopper and whitefly populations were observed in 31 cotton entries planted at Bet She'an, Israel, in 1987. Leafhopper populations decreased but the whitefly populations increased as the number of trichomes increased. At the end of June, plants with 40 trichomes per 13.7 mm2 supported relatively low populations of both leafhoppers and whiteflies. However, the whitefly populations increased later in the season to 43 times the earlier population levels. Whitefly populations increased as the number of trichomes increased up to 70 trichomes per 13.7 mm2 and then decreased as the trichomes became more dense. Various control measures and breeding schemes that might interact to provide an answer to the control of these pests are discussed.  相似文献   

19.
Mature leaves of field-grown eddo plants were used for observing hydathode morphology by light and scanning electron microscopies. There were approximately five hydathode pores on the adaxial surface of each leaf tip. A ring structure with two borders around the pore was detected in this study. Further observations revealed a large cavity underneath the pores. The cavity was directly connected to vascular bundles that lacked a bundle sheath, via intercellular spaces among loosely organized parenchyma cells. Many crystal cells were present around the cavity and vascular bundles. To evaluate the role of guttation in sodium excretion under salinity stress, eddo plants were grown in hydroponic solutions containing 0, 1, 4, 8, and 12 mM sodium chloride (NaCl) for 7 d. As the NaCl concentration in the hydroponic solution increased, the sodium contents increased in leaf blades, petioles, and roots but remained unchanged in corms. The sodium concentration in the guttation fluid increased; however, the volume of guttation fluid decreased with increasing NaCl concentrations. Therefore, sodium elimination via guttation decreased with increasing NaCl concentrations. The ratios of the sodium content in guttation fluid to that of leaf blades, leaves, and whole plants decreased with increasing NaCl concentrations. The ratios of potassium to sodium contents in leaves, roots, and guttation fluid also decreased as the NaCl concentration increased. These results indicate that guttation did not eliminate sufficient sodium to play a role in adjusting sodium homeostasis and the ratios of potassium to sodium contents in eddo plants under saline conditions.  相似文献   

20.
干旱胁迫下不同苎麻品种的形态解剖特征研究   总被引:3,自引:0,他引:3  
抗旱性强的苎麻品种,在正常水分条件下叶面茸毛多、叶着生角度小、比叶重大,而在干旱胁迫下叶片衰老慢,根冠比大、根活跃吸收面积大、萝卜根数量多且直径大,纤维细胞直径和胞壁厚度降低幅度小。抗旱性强的苎麻品种正常水分及干旱条件下叶片气孔密度以及茎导管和根系维管束均较大。  相似文献   

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