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911.
912.
To evaluate differences in growth and adaptability of maritime pine (Pinus pinaster Ait.), we studied growth, polycyclism, needle tissue carbon isotope composition (delta(13)C) as an estimate of water-use efficiency (WUE) and survival of seven populations at 10 years of age growing in a performance trial at a provenance test site in Escaroupim, Portugal. Six populations were from relatively high rainfall sites in Portugal and southwestern France (Atlantic group), and one population was from a more arid Mediterranean site in Spain. There were significant differences between some populations in total height, diameter at breast height, delta(13)C of bulk needle tissue, polycyclism and survival. A population from central Portugal (Leiria, on the Atlantic coast) was the tallest and had the lowest delta(13)C. Overall, the variation in delta(13)C was better explained by the mean minimum temperatures of the coldest month than by annual precipitation at the place of origin. Analyses of the relationships between delta(13)C and growth or survival revealed a distinct pattern for the Mediterranean population, with low delta(13)C (and WUE) associated with the lowest growth potential and reduced survival. There were significant negative correlations between delta(13)C and height or survival in the Atlantic group. Variation in polycyclism was correlated with annual precipitation at the place of origin. Some Atlantic populations maintained a high growth potential while experiencing moderate water stress. A detailed knowledge of the relationships between growth, survival and delta(13)C in contrasting environments will enhance our ability to select populations for forestry or conservation. 相似文献
913.
We quantified ascorbate, glutathione and alpha-tocopherol in fine roots of mature Fagus sylvatica L. under free-air canopy ozone (O(3)) exposure (twice ambient O(3) concentration, 2x[O(3)]) during two growing seasons that differed in the extent of summer drought (exceptional drought year 2003, average year 2004). This design allowed us to test whether O(3) exposure or drought, or both, affected root antioxidants during the growing season. In both years, root ascorbate and alpha-tocopherol showed a similar relationship with volumetric soil water content (SWC): ascorbate concentrations on a root dry mass basis increased from about 6 to 12 micromol g(-1) when SWC dropped from 25 to 20%, and a-tocopherol increased from 100 to 150 nmol g(-1) at SWC values below 20%. Root glutathione showed no relationship with SWC or differences between the dry and the average year, but it was significantly and consistently diminished by 2x[O(3)]. Our results were inconclusive as to whether shoot-root translocation of glutathione or glutathione production in the roots was diminished. Phloem glutathione concentrations in the canopy remained constant, but reduced transport velocity in the phloem and, as a consequence, reduced mass flow of glutathione cannot be ruled out. 相似文献
914.
Federico Tinivella Lucia M. Hirata Mikael A. Celan Sandra A. I. Wright Tahsein Amein Annegret Schmitt Eckhard Koch Jan M. van der Wolf Steven P. C. Groot Dietrich Stephan Angelo Garibaldi Maria Lodovica Gullino 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(2):139-151
Greenhouse trials were carried out in order to test the efficacy of different seed treatments as alternatives to chemicals
against Colletotrichum lindemuthianum cause of anthracnose on bean and Ascochyta spp. cause of Ascochyta blights on pea, respectively. Resistance inducers, commercially formulated microorganisms, non-formulated
selected strains of different microorganisms (fungi, bacteria and yeasts) and plant extracts were applied as dry or liquid
seed treatments on naturally infested seeds. Seedling emergence and disease incidence and/or severity were recorded. Almost
all seed treatments turned out to be ineffective in controlling the Ascochyta infections, which is in line with the literature
stating that these pathogens are difficult to control. The only alternative treatments that gave some control of Ascochyta spp. were thyme oil and a strain of Clonostachys rosea. The resistance inducers tested successfully controlled infections of bean by C. lindemuthianum. Among the formulated microorganisms, Bacillus subtilis-based formulations provided the best protection from anthracnose. Some strains of Pseudomonas putida, a disease-suppressive, saprophytic strain of Fusarium oxysporum and the mustard powder-based product Tillecur also proved to be effective against bean anthracnose. However, among the resistance
inducers as well as among the other groups, certain agents caused a significant reduction of plant emergence. Different alternative
seed treatments can therefore be used for the control of C. lindemuthianum on bean, while on pea only thyme oil and a strain of Clonostachys rosea showed some effectiveness against Ascochyta spp. 相似文献
915.
In our previous study, RAPD (Random Amplified Polymorphic DNA) analysis revealed species-specific markers for three medicinal Echinacea species (Asteraceae): E. angustifolia DC., E. pallida (Nutt.) Nutt. and E. purpurea (L.) Moench. In the present work, we have converted a RAPD marker (750 bp) for E. purpurea into a SCAR (Sequence Characterized Amplified Region) marker. SCAR-PCR, in fact, revealed the expected amplicon (330 bp) only in E. purpurea and not in the other two species, giving further evidence for differences in medicinal Echinacea spp. genome and confirming a greater similarity between E. pallida and angustifolia. 相似文献
916.
Morphological characterisation and agronomic evaluation was conducted on 12 transgenic broccolilines containing a tomato antisense1-aminocyclopropane-1-carboxylic
acid (ACC) oxidase gene. Plants of three cultivars: Shogun (Sh), Green Beauty (Gy) and Dominator (D), were regenerated from
hairy root cultures after co-cultivation with Agrobacterium rhizogenes strain A4T harbouring the binary vector pLN35. The T-DNA of pLN35 contains genes encoding a tomato antisense ACC oxidase
gene (35S-ACC-5′7′) and a neomycin phosphotransferase II gene (NOS-NPTII-NOS) for kanamycin resistance. The transgenic plants
were transferred to a greenhouse and fertile plants obtained. Integration of the foreign DNA into the broccoli genome was
confirmed by the polymerase chain reaction and Southern analyses. Transgenic plants showed evidence of hairy root (HR)-induced
morphological changes to varying degrees. Of the 12 characterised transgenic lines, three lines(Gy/7, D/1 and D/2) performed
within the limits of acceptability for all head quality parameters analysed (size, density, colour, shape and leafiness).
The ethylene production from stalks of four field-grown transgenic lines of Green Beauty broccoli showed significant reductions
in activity relative to the control 98 h after harvest. The Dominator transgenic lines D/1 and D/2 showed significant improvements
in head colour relative to the control from 48 h after harvest. These results are consistent with the ethylene production
patterns determined previously for these lines. The head colour results are consistent with previous results suggesting that
two enzyme systems may be involved in broccoli senescence, giving two bursts of ethylene production, with only the second
burst inhibited by the antisense ACC oxidase gene used.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
917.
The distribution pattern and diversity of Collembola communities in the soils of low and high intertidal saltmarshes were compared. The intertidal “mud” soils are colonized by Collembola to depth of 30 cm and at a distance of 10 m towards the sea from coastal edge. The communities of Collembola in low intertidal saltmarsh soils are dominated by a population of Archisotoma sp. The contents of organic matter in the intertidal saltmarsh soils influenced the distribution of Archisotoma sp. 相似文献
918.
Alvim Ferraz Maria C. M. Lourenço João C. Becker Senta 《Water, air, and soil pollution》2000,120(3-4):261-272
Gaseous effluent from the treatment of contaminated soils must becontrolled to avoid atmospheric emissions of volatile organiccompounds during remediation. The combination of carbonadsorption with catalytic deep oxidation for control ofcyclohexane emissions is analysed in this paper. The activitiesof activated carbons prepared with almond shells and impregnatedwith CoO, Co3O4 and CrO3 were compared, inrelation with carbon structure, catalyst content and catalystspecies. The microcatalytic-chromatographic technique developedwas very suitable for rapid comparison of the catalyticactivities. Carbons with a better development of surface areaand pore volumes showed higher catalytic activities. Theincreasing of catalyst content also increased catalyticactivity. Cobalt is better than chromium to catalyse the deepoxidation of cyclohexane, the oxidation state of cobalt inCo3O4 being better than in CoO. 相似文献
919.
Maria Eugenia Caceres Fulvio Pupilli Efisio Piano Sergio Arcioni 《Genetic Resources and Crop Evolution》2000,47(4):455-459
The potential use of RFLP molecular markers for the identification of four creeping bentgrass (Agrostis stolonifera L.) cultivars and one variety of A. tenuis Sibth. used as control, was investigated. Seven probes out of the total 44 screened were able to differentiate all five cultivars at once. On the basis of their genetic similarity the varieties bred at the Pennsylvania State University were grouped closely together, whereas the variety Prominent and the A. tenuis control were more distantly related. 相似文献
920.
Maria Charmela D Ates Gerald F Quinitio Emilia T Quinitio Roman C Sanares 《Aquaculture Research》2012,43(2):215-225
Morphological changes in the embryos, egg size and development, incubation period and morphological structures of newly hatched zoea of three mud crab Scylla species were determined. The three species exhibited similar embryonic development composed of 10 stages. The mean egg diameter of Scylla serrata was significantly larger (P<0.05) at the prehatch stage. The mean egg diameters of Scylla tranquebarica and Scylla olivacea were similar (P>0.05). The incubation period was the longest in S. serrata and the shortest in S. olivacea. There was a positive relationship between egg size and larval size, as S. serrata exhibited the largest egg size and first zoea. However, no correlation was detected between egg size at prehatch and lengths of the morphological structures of the newly hatched zoea. The three species exhibited similar lengths of cephalic structures, but S. olivacea had significantly shorter (P<0.05) abdominal structures. The duration of spawning from ablation was the shortest in S. tranquebarica and the longest in S. olivacea. The study is relevant to aquaculture and fisheries management of Scylla species. 相似文献