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1.
Fourteen taxa of the Triticum-Aegilops group have been investigated for their sieve-element plastids. At maturity they contain dense and thin crystalloid inclusions and are classified into the PIIc' plastid type; onlyAe. comosa var.biaristata lacked the thin crystalloids and thus conforms to the PII c type. The proteinaceous nature of the crystalloids was demonstrated by application of proteolytic enzymes. Ultrastructural evidence suggests that both kinds of crystalloid inclusions are involved in the sealing of sieve-plate pores of injured sieve tubes. Measurements and calculations of the spacings and angles carried out on crystalloid prints permitted the construction of a two- and three-dimensional pattern forT. aestivum thin crystalloids.  相似文献   

2.
The effect of potassium starvation on stomatal conductance was studied in olive trees and sunflower plants, two major crops with greatly differing botanical characteristics. In both species, K(+) starvation inhibited water-stress-induced stomatal closure. In olive trees, potassium starvation favoured stomatal conductance and transpiration, as well as inhibiting shoot growth, in the three cultivars studied: 'Lechín de Granada', 'Arbequina' and 'Chetoui'. However, 'Lechín de Granada' - generally considered more drought-tolerant than 'Arbequina' and 'Chetoui' - proved less susceptible to potassium starvation. Results for olive trees also suggest genetic variability in olive cultivars in relation to potassium requirements for stem growth and the regulation of water transpiration. The results obtained suggest that inhibition of the stomatal closure mechanism produced by moderate potassium starvation is a widespread plant physiological disorder, and may be the cause of tissue dehydration in many water-stressed crops.  相似文献   

3.
To assess the genetic diversity in Moroccan cultivated olive, Olea europaea L. subsp. europaea, we performed molecular analysis of olive trees sampled in four geographic zones representing all areas of traditional olive culture. The analysis of 215 trees using 15 simple sequence repeat (SSR) loci revealed 105 alleles distributed among 60 SSR profiles. The analysis of chloroplast deoxyribonucleic acid polymorphism for these 60 olive genotypes allowed to identify four chlorotypes: 42 CE1, one CE2, nine COM1 and eight CCK. Among the 60 SSR profiles, 52 corresponded to cultivated olive trees for which neither denomination nor characterisation is available. These local olive genotypes displayed a spatial genetic structuring over the four Moroccan geographic zones (northwest, north centre, Atlas and southwest), as pairwise Fst values ranged from 0.0394 to 0.1383 and varied according to geographic distance. As single alleles detected in local olive were also observed in Moroccan oleaster populations, results suggest that plant material was mainly selected from indigenous populations. The assumption that Picholine marocaine cultivar is a multi-clonal cultivar was not supported by our data because we found a single genotype for 112 olive trees representing 31 to 93% of the olives sampled locally in the 14 different areas. Picholine marocaine and the few other named cultivars do not seem to belong to the same gene pools as the unnamed genotypes cultivated only locally. The situation is paradoxical: a substantial genetic diversity in Moroccan olive germplasm, probably resulting from much local domestication, but a single cultivar is predominant.  相似文献   

4.
番茄种子及萌发过程中蛋白体超微结构的研究   总被引:3,自引:0,他引:3  
对番茄种子蛋白体的结构,类型及萌发过程中的变化进行了详细观察,未萌发种子蛋白体周围由一单层膜包裹,内部为蛋白质基质及分布其中的内含物3部分组成,根据内含物形态和性质上的不同可分为球状晶体,拟晶体和簇晶体3种形式,根据蛋白体所含内含物的不同,将蛋白体划分为5种基本类型:(1)基质蛋白体;(2)球状晶体蛋白体;(3)拟晶体蛋白体;(4)簇晶体蛋白体;(5)复合蛋白体。萌发过程中,蛋白体逐渐降解并液泡化  相似文献   

5.
The orderCaryophyllales (Centrospermae) was found to contain specific P-type sieve-element plastids which are characterized by protein inclusions composed of ring-shaped bundles of filaments and of central crystalloids. The sieve-element plastids of 14 families (140 species investigated) fit into this overall characterization, and more specific details are used to delimit the families and arrange them within the order.Phytolaccaceae, the basic family of the order display much diversity: the crystalloids inside their plastids are either globular (most genera) or polygonal (Stegnosperma), starch may also be present (Phytolacca).Nyctaginaceae, with starch inBougainvillea sieve-element plastids, can be derived directly fromPhytolacca. Globular crystalloids are present in most of the families, as inDidiereaceae, Cactaceae, Aizoaceae-Tetragoniaceae, Portulacaceae-Basellaceae-Halophytaceae-Hectorellaceae. Caryophyllaceae andLimeum ofMolluginaceae contain polygonal crystalloids (otherMolluginaceae with globular crystalloids). Crystalloids are entirely absent fromChenopodiaceae (incl.Dysphaniaceae) andAmaranthaceae. The probable relationships between these families are presented diagrammatically in Fig. 13. Bataceae, Gyrostemonaceae, Vivianiaceae, Theligonaceae, Polygonaceae, Plumbaginaceae, Fouquieriaceae, Frankeniaceae, andRhabdodendraceae—all at some time included into theCaryophyllales (Centrospermae) or doubtfully referred to them—develop S-type (or different P-type) sieve-element plastids. Their direct connection to theCaryophyllales therefore is excluded. Finally, evolutionary trends of theCaryophyllales are discussed.Presented in the Symposium Evolution of Centrospermous Families, during the XIIth International Botanical Congress, Leningrad, July 8, 1975.  相似文献   

6.
Irrigation effects on whole-plant sap flow and leaf-level water relations were characterised throughout a growing season in an experimental olive (Olea europaea L.) orchard. Atmospheric evaporative demand and soil moisture conditions for irrigated and non-irrigated olive trees were also monitored. Whole-plant water use in field-grown irrigated and rain fed olive trees was determined using a xylem sap flow method (compensation heat-pulse velocity). Foliage gas exchange and water potentials were determined throughout the experimental period. Physiological parameters responded diurnally and seasonally to variations in tree water status, soil moisture conditions and atmospheric evaporative demand. There was a considerable degree of agreement between daily transpiration deduced from heat-pulse velocity and that determined by calibration using the Penman–Monteith equation in the field. Summer drought caused decreasing leaf gas exchange and water potentials, and a progressive increase in hydraulic conductance (stronger in non-irrigated than irrigated trees), probably attributable to modifications in hydraulic properties at the soil-root interface. Negligible hysteresis, attributable to low plant capacitance, was observed in the relationship between leaf water potential and sap flow. A proportional decrease in maximum daily leaf conductance with increasing vapour pressure deficit was observed, while mean daytime canopy stomatal conductance decreased with the season. As a result, plant water use was limited and excessive drought stress prevented. Non-irrigated olive trees recovered after the summer drought, showing a physiological behaviour similar to that of irrigated trees. In addition to physiological and environmental factors, there are endogenous keys (chemical signals) influencing leaf level parameters. Olive trees are confirmed to be economical and sparing users of soil water, with an efficient xylem sap transport, maintenance of significant gas exchange and transpiration, even during drought stress.  相似文献   

7.
Sandra D. Gomes 《Grana》2013,52(3):228-231
The possible impact of altitude and the related microclimatic conditions on the total production of fruiting branches, inflorescences, flowers and pollen grains of olive trees Olea europaea was analysed. A total of 90 Picual cultivar trees, the most extensive olive cultivar in the Iberian Peninsula, were studied for a three-year period (2007–2009). The study shows that production of flowers and pollen grains in a cultivar of the olive tree varies according to the microclimate. Our study also indicates that the olive trees frequently can have up to half a million flowers per tree. Moreover, the total flower production differs between years and study areas. In the Picual cultivar, the average production of pollen grains per anther is usually more than 60?000 grains. The total production of pollen per tree is around 72?000 million on average. The most favourable microclimatic conditions for reproduction in olive trees are found in years and olive growing areas with low temperature and high precipitation records during the months prior to flowering of the olive trees. We hypothesise that olive trees tend to increase their pollen production rate as altitude increases, which can be interpreted as a reproductive strategy to ensure fertilisation.  相似文献   

8.
Lebanon, an East Mediterranean country, does not have a comprehensive reference national olive collection. A report published 30 years ago indicated the presence of four Lebanese varieties, but the confusion regarding these varieties was discussed then and is still prevalent today hindering prospects for conserving and exploring the national germplasm. This study assessed the existing in situ diversity of old Lebanese olive groves using simple sequence repeat (SSR) and amplified fragment length polymorphisms (AFLP). Trees (140) were collected from 14 groves located in the four traditional olive areas. Analysis was based on 22 polymorphic alleles produced from six SSR primers, and on 135 polymorphic AFLP fragments. SSR and AFLP did not yield consistent results in terms of level of polymorphism, with SSR detecting higher variation than AFLP. On the other hand, both clustered trees based on geographic provenance. AFLP coefficient of similarity between trees ranged between 0.70 and 0.99 indicating the possible presence of varieties since some values fall within reported intervarietal ranges of 0.65 to 0.84. SSR unveiled the presence of nine different genotypes: four corresponding each to a provenance and five consisting of single trees characterized by the presence of less frequent alleles with an average of 0.33. Results also revealed a high incidence of clones greater than 90% in three of the four provenances. The findings of this study point for the need to plan for a sampling strategy that takes into consideration geographic provenances.  相似文献   

9.
Abstract The method used most extensively in Europe to prevent damage due to browsing of woody plants consists of shelter pipes made of plastic material or net. This system, however, is not practical for plants such as olive trees where it is desirable for the branches to develop more than the trunk. For this reason, in an area with a high deer (Dama dama) population, three liquid repellents were tested for their ability to prevent damage by cervids to olive seedlings (Olea europaea). Tree Guard and Eutrofit reduced the percentage of plants browsed with respect to the control by a statistically significant extent through the third week (54.5 and 40.9% reduction, respectively), while for Hot Sauce, the differences did not reach significance after the first week. Tree Guard and Eutrofit were also able to reduce the level of damage for the entire eight week period of the test, while Hot Sauce did not differ from the control in a statistically significant manner. The use of repellent substances such as Tree Guard and Eutrofit to reduce the damage caused by cervids to olive groves therefore seems a possible strategy under conditions of medium and low density of animals. Eutrofit was the most economical product from the point of view of cost effectiveness.  相似文献   

10.
Summary High concentrations of proteinaceous crystalloids accumulate in vegetative cells of the red algaWrangelia plumosa Harvey but disappear prior to sporogenesis. The distinctly structured crystalloids lack a bounding membrane and appear to autopolymerize within the cytoplasm. Chemical analysis of isolated crystalloids showed the presence of all amino acids except cysteine and cysteic acid. Carbohydrate accounted for 7.5% of the preparation. The crystalloids appear to have a storage function during growth and development.  相似文献   

11.
In the present study, we proposed to determine the genetic diversity and relationships between local cultivars and wild olive trees from three important olive-growing regions, i.e., Marmara, Aegean, and Mediterranean, of Turkey. This is the first known large-scale molecular study to investigate the relationships between local cultivars and wild olives from the eastern Mediterranean basin. Two hundred and four oleaster trees and 27 cultivars were sampled to represent molecular diversity. We used 11 simple sequence repeat and 13 sequence-related amplified polymorphism markers to assess genetic variations and inter-relationships among the samples. The results of the analysis showed differences in the levels of allelic composition and heterozygosity between cultivated and wild olive trees. The observation of a high proportion of a certain wild-type genetic background in the cultivars may indicate the former use of local wild trees in olive domestication in Turkey, a possible autochthonal origin of cultivars. “Gemlik” was found to be the most common olive cultivar in the Marmara region and most of the wild olive samples from this region may be feral forms derived from cultivar seed spreading. The information obtained from this study can help to assist the management of an olive collection and sheds some light on the origin of Turkish olive cultivars.  相似文献   

12.
Floral phenology, as most of natural phenomena, shows, as an inherent feature, a high degree of spatial continuity. Geostatistics are a family of statistics that describe correlations through space/time and they can be used for both quantifying spatial correlation and interpolating no monitored sampling points. The combined use of Geographical Information Systems (GIS) and geostatistics can be an essential tool for spatial analysis in phenological and aerobiological studies. In the present work, Kriging interpolation by using linear geostatistic analysis has allow us to estimate phenological data of a wide olive crop area of the province of Cordoba (Andalusia, Southern Spain), on the basis of a limited number of␣phenology sampling points. The main a priori hypothesis was that 7 traditionally observed sampling points (with 10 olive trees in each site) uniformly distributed through the main olive crop areas could be enough for interpolating phenological information of the whole Cordoba olive area. Geostatistical results reject this hypothesis. The optimum/minimum number and location of sampling points was determined in 13 sites (including the original 7 sites and 6 new sites). The obtained phenological maps will improve␣olive pollen aerobiological information and forecasting in the area. The application of such new combined space analysis tools on floral phenology allows optimising human and economic resources on field phenology campaigns. Moreover, an appropriate use of GIS and geostatistic software to create phenological maps will be an essential complement in pollen aerobiological studies, given the increased interest in obtaining automatic aerobiological forecasting maps.  相似文献   

13.
14.
A. Bosabalidis  I. Tsekos 《Planta》1982,156(6):496-504
Glandular scales of Origanum dictamnus L. originate from a single protodermal cell. They are composed of a 12-celled head and an unicellular stalk and foot. During the early stages of gland differentiation, the head cells possess a small number of plastids which contain globular inclusions. Similar inclusions are also observed in the plastids of the stalk and the foot cell. The lateral walls of the stalk cell progressively undergo cutinization which does not extend to the upper and lower periclinal walls. At the onset of secretion the electron density of the plasmalemma region lining the apical walls of the head cells remarkably increases. These walls are impregnated with an osmiophilic substance identical in appearance to the content of the subcuticular space. In a following stage of the secretory process osmiophilic droplets of various size arise in the cytoplasm of the secretory cells which undergoes simultaneously a reduction of its initial density. After secretion has been concluded the protoplast of the head cells becomes gradually degenerated. The chlorenchyma cells of the mesophyll possess numerous microbodies closely associated with various organelles. In the cytoplasm of these cells crystalloids occasionally occur.  相似文献   

15.
For thousands of years, olive trees (Olea europaea L.) have been a significant presence and a symbol in the Garden of Gethsemane, a place located at the foot of the Mount of Olives, Jerusalem, remembered for the agony of Jesus Christ before his arrest. This investigation comprises the first morphological and genetic characterization of eight olive trees in the Garden of Gethsemane. Pomological traits, morphometric, and ultrastructural observations as well as SSR (Simple Sequence Repeat) analysis were performed to identify the olive trees. Statistical analyses were conducted to evaluate their morphological variability. The study revealed a low morphological variability and minimal dissimilarity among the olive trees. According to molecular analysis, these trees showed the same allelic profile at all microsatellite loci analyzed. Combining the results of the different analyses carried out in the frame of the present work, we could conclude that the eight olive trees of the Gethsemane Garden have been propagated from a single genotype.  相似文献   

16.
Polymorphism in the lengths of restriction fragments of the whole cpDNA molecule was studied in cultivated olive and in oleaster (wild olive) over the whole Mediterranean Basin. Seventy two olive cultivars, 89 very old trees cultivated locally, and 101 oleasters were scored for ten endonucleases. Moreover, maternal inheritance of cpDNA in olive was shown by analysing the progeny of a controlled cross between two parents which differed in their cpDNA haplotypes. In the whole species, three site- and three length-mutations were observed, corresponding to five distinct chlorotypes. The same chlorotype (I) was predominant in both oleasters and cultivated olive trees, confirming that these are closely related maternally. Three other chlorotypes (II, III and IV) were observed exclusively in oleaster material and were restricted either to isolated forest populations or to a few individuals growing in mixture with olive trees possessing the majority chlorotype. An additional chlorotype (V) was characterised by three mutations located in distinct parts the cpDNA molecule but which were never observed to occur separately. This chlorotype, more widely distributed than the other three, in both cultivated and wild olive, and occurring even in distant populations, was observed exclusively in male-sterile trees showing the same specific pollen anomaly. However, in the present study, no evidence was provided for a direct relationship between the occurrence of the cpDNA mutations and male sterility. It is suggested that the large geographic distribution of chlorotype V may be related to the high fruit production usually observed on male-sterile trees. These may be very attractive for birds which are fond of olive fruit and spread the stones efficiently. Probably for the same reason, people preserved male-sterile oleasters for long periods and, in several places, used male-sterile cultivars over large areas. Received: 25 November 1998 / Accepted: 19 December 1998  相似文献   

17.
Fine structural studies of the epididymis of mature mongrel dogs and of Sprague-Dawley rats were undertaken in conjunction with research dealing with the effects of vasectomy upon this organ. This paper reports the observation of crystalloid and lamellar inclusions present in these species following fixation of the epididymis in 5 % glutaraldehyde, post-fixation in osmium, and routine processing for electron microscopy. In the dog, crystalloid inclusions were observed within the cauda epididymidis of unoperated and vasectomized animals. They were found within the apical cytoplasm of principal cells in association with the Golgi apparatus and endoplasmic reticulum, and in some instances, in close proximity to the nucleus. These crystalloids exhibited a 12 nm periodicity and often measured over 3 μm in length. In the rat, two types of inclusions were found, one within mitochondria of clear cells from unoperated animals and another within membrane-bound bodies of principal cells from the caput epididymidis of unoperated and vasectomized animals. The mitochondria which contained inclusions were basally located and were observed in stacks of up to eight elongate mitochondria each. The mitochondrial inclusions exhibited a complex lamellar structure with an approximate periodicity of 36 nm. In contrast, the crystalloid inclusions found within principal cells were sequestered within supranuclear cytoplasmic bodies which increased in number with age. Such crystalloids exhibited a linear periodicity of 11–13.5 nm, but the precise lattice structure remains to be determined. Although certain aspects of the morphology of these bodies suggests a relationship to microbodies, we have been unable to demonstrate catalase activity within them. At present, neither the origin of crystalloid structures described, nor their relationship to epididymal physiology is clear.  相似文献   

18.
Cytoplasmic vacuoles seen in methanol-fixed, Giemsa's-stained ookinetes of Leucocytozoon simondi, Parahaemoproteus fringillae and Plasmodium gallinaceum, when studied with the electron microscope, were found to correspond with crystalloid inclusions of similar structure, particle size, and arrangement. Cytochemical examination of these “crystalloids” revealed their lipid-protein nature. Morphologically similar inclusions were found also in ookinetes of Leucocytozoon ziemanni and Parahaemoproteus velans. In L. simondi, crystalloid is formed rapidly after fertilization, from amorphous electron dense material seen in mature macrogametocytes. The arrangement and distribution of crystalloids in the zygote, ookinete, oocyst, and sporozoite are described. On the basis of differences in structure and particle size, it is proposed that the crystalloid inclusions in Haemosporina be divided into 2 types. Type I—lipid-protein in nature, characterized by electron dense irregularly spherical particles, 25–40 nm in diameter, with individual particles not invested by membrane. Type II—probably virus, characterized by electron dense, irregularly spherical, membrane-bounded particles, with a diameter usually greater than 40 nm.  相似文献   

19.
Animals may disperse cultivated trees outside the agricultural land, favoring the naturalization or, even, the invasiveness of domestic plants. However, the ecological and conservation implications of new or unexplored mutualisms between cultivated trees and wild animals are still far from clear. Here, we examine the possible role of an expanding and, locally, overabundant pigeon species (Columba palumbus) as an effective disperser of domestic olive trees (Olea europaea), a widespread cultivated tree, considered a naturalized and invasive species in many areas of the world. By analyzing crop and gizzard content we found that olive fruits were an important food item for pigeons in late winter and spring. A proportion of 40.3% pigeons consumed olive seeds, with an average consumption of 7.8 seeds per pigeon and day. Additionally, most seed sizes (up to 0.7 g) passed undamaged through the gut and were dispersed from cultivated olive orchards to areas covered by protected Mediterranean vegetation, recording minimal dispersal distances of 1.8–7.4 km. Greenhouse experiments showed that seeds dispersed by pigeons significantly favored the germination and establishment in comparison to non-ingested seeds. The ability of pigeons to effectively disperse domestic olive seeds may facilitate the introduction of cultivated olive trees into natural systems, including highly-protected wild olive woodlands. We recommend harvesting ornamental olive trees to reduce both pigeon overpopulation and the spread of artificially selected trees into the natural environment.  相似文献   

20.
The inheritance of mitochondrial and chloroplast genomes does not follow Mendelian laws, but proceeds by vegetative segregation. Most organisms show organelle homoplasmy, which is probably produced and maintained during sexual reproduction. We have tested the effect of prolonged vegetative multiplication in the maintenance of mitochondrial homoplasmy and the generation of heteroplasmy in cultivated olive trees, Olea europaea L. Seven trees, each representing a different variety of olive, were analysed by the study of an intergenic spacer region of the mitochondrial genome. A very high level of heteroplasmy was detected in all cases. We found multiple genome variants of the sequence analysed. The frequency of genomes with no changes in the spacer region was 11.5%. This means that 88.5% of genomes contain at least one change. The same spacer mitochondrial region was sequenced in several clones from four olive trees of a second generation of sexually reproduced trees. In these trees, many clones were identical and had no changes, which represents a clear reduction of the heteroplasmy (p < 0.001). Therefore, this work supports the relevance of the role of sexual reproduction in the maintenance of mitochondrial homoplasmy and also shows that mutations accumulate in a non-coding sequence of the mitochondrial genome when vegetative propagation is maintained for a long period of time.  相似文献   

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