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1.
以两种不同稀释浓度的海水(3和6西门子/米)滴灌“PClll”蕃茄,分别在第一片真叶(早期)和第一个裂果出现(晚期)时进行。一般而言,盐分提高了风味、可溶性固形物及糖的浓度,减少了色斑。因而提高了果实的总体品质,货架寿命未受盐处理的影响。最重要的发现是:在植物发育后期,用低浓度盐水灌溉,其总产量与对照相比无实质性的差异、达出口质量的产量相同,而果食的品味远比对照好。沙漠地区温室栽培的蕃茄,采用盐水灌溉的方法提高果食品质是可行的。 相似文献
2.
Oxidative stress indicators, malondialdehyde (MDA) accumulation and chlorophyll retention, were tested as tools for salt‐tolerance screening in Chloris gayana (Kunth), a forage grass exhibiting inter‐ and intra‐cultivar variability in the response to salt stress. Three types of experimental system were compared, salt shock, gradual salt treatment and leaf segments floated on control and saline solutions. Results followed the same trend in the three systems, but leaf segments or gradually salinized plants are the most convenient. Lower mean MDA and higher mean chlorophyll content were found under salinity in cv. ‘Katambora’, which is considered, from previous field trials, to be more salt tolerant than cv. ‘Boma’. Nevertheless, chlorophyll content did not give consistent results in other tests and it is not recommended for selection purposes. Within cv. ‘Boma’, clones rating higher in a salt tolerance evaluation under greenhouse conditions had lower MDA content under salinity and lower mean MDA ratios between salt‐treated and control samples. The survival of 80‘Boma’ plants under increasing NaCl concentration was assessed and MDA was measured in the leaves of very plant before the final NaCl level was reached, to assess whether it was predictive of survival capability. MDA values were significantly lower in the group surviving longer, thus, a selection based on low MDA values would have enriched the original population with more tolerant individuals. 相似文献
3.
Summary Salt tolerance in Andean potatoes can be a source for this trait in cultivated potatoes or be exploited to expand potato cultivation
to more marginal areas. The purpose of this study was to determine salt tolerance in twelve Argentine Andean potato varieties
through the response of nodal segments cultured in vitro and to evaluate whether changes in Na+, K+ or proline accumulation associate with salt tolerance. Genotypes Bianca, Airampia, Sisa Sani and Cuarentilla were the most
tolerant. The most susceptible varieties were Balcacha, Runa Rosada, Collareja, Overa, Bianca Redonda and Papa Baya, while
Cuarentona and Colorado Ml comprised an intermediate group. These results indicate that variability for salt tolerance exists
in this germplasm, and highlights its potential use in breeding programmes. No association was found between the salt tolerance
rating and changes in K+, Na+ and proline accumulation in a salt gradient, thus precluding the use of these parameters as predictors for salt tolerance
of these species in in vitro studies. 相似文献
4.
Genetic variability for responses to short‐ and long‐term salt stress in vegetative sunflower plants
Dolores Bustos Leandro Ismael Ortega Alicia Córdoba Abelardo Vegetti Edith Taleisnik 《植物养料与土壤学杂志》2012,175(6):882-890
Sunflower (Helianthus annuus L.) has been rated as moderately salt‐resistant, and variability for salt resistance has been detected within this crop. However, variability in salt‐resistance mechanisms has not been assessed. Osmotic tolerance, the relation of salt resistance with whole‐plant Na+ and K+ distribution and tissue Na+ tolerance were investigated in several sunflower inbred lines. Plants were grown under controlled conditions, in pots with sand and perlite irrigated with salinized (NaCl, –0.65 MPa) nutrient solution. Osmotic tolerance was assessed from the initial effects of the salt treatment on plant elongation in eleven sunflower lines. Long‐term salinity responses were evaluated in four of those lines, by assessing whole‐plant growth. A principal components analysis (PCA) was run on relative‐to‐control growth data, and this information was used to establish a relative resistance ranking, which indicated lines HAR2 > HAR1 > HA64 > HAR5. Osmotic tolerance was observed in HA64 and HAR2. The lines showed different degrees of Na+ accumulation, it was very low in some of them, but relative salt resistance was not associated to this trait. Tissue Na+ tolerance was deduced by comparing the percentage of dead leaves as a function of leaf blade Na+ accumulation, and it was higher in HAR1 than in the rest. These results indicate that variability for salt‐resistance mechanisms exists in sunflower. Osmotic tolerance and tissue Na+ tolerance were detected in different lines, highlighting that such variability may be exploited for increasing salt resistance in this crop. 相似文献
5.
Pérez Bravo Ongaro Castagnaro L. García Seffino & Taleisnik 《Grass and Forage Science》1999,54(4):289-296
Variability in the response to salinity within Chloris gayana (Rhodes grass) germplasm was evaluated under field conditions, and random amplified polymorphic DNA (RAPD) markers were used to assess genetic relatedness among cultivars/accessions. RAPD analysis showed a clustering of cultivars of known relatedness: cv. Pioneer and accessions Local and Trancas (derived from an old Pioneer pasture established in saline soil) belonged to the same cluster, Katambora to another and tetraploid Boma and Callide could be further separated, Boma belonging to a fourth, distant cluster. Field experiments were laid out in two types of plots: control [with electrical conductivity of the saturation extract (EC) = 3·64 dS m−1 ] and saline (EC=13·10 dS m−1 ) and two experiments were carried out: one to evaluate the effects of salinity on emergence and establishment, and the other, with a uniform number of plants per plot, to evaluate yield under saline conditions. All cultivars/accessions had salinity-associated decreases in dry-matter (DM) production during the establishment phase. After this stage, 1-year DM yield was similar in all cultivars within each salinity level and production in the saline plots was significantly lower than in controls only in cv. Callide and accession Trancas. Second-year production in the non-saline plots increased by 30% on average over the previous year, whereas an average 40% reduction was observed in the saline plots. Thus, salinity had a negative effect on Rhodes grass establishment and persistence. The cultivars could not be ranked unequivocally by production under saline conditions, but tetraploids Boma and Callide may be said to be less tolerant than the rest on the basis of an increased proportion of dead leaves and decreased number of stolons observed in the saline plot. 相似文献
6.
Characterization of the effect of high salinity on roots of Chloris gayana Kunth: carbohydrate and lipid accumulation and growth 总被引：1，自引：0，他引：1
A. Córdoba L. García Seffino H. Moreno C. Arias K. Grunberg A. Zenoff & E. Taleisnik 《Grass and Forage Science》2001,56(2):162-168
Branched nodal roots comprise the largest portion of the root system mass in Chloris gayana Kunth and the effects of high salinity on nodal root appearance and elongation rates were analysed in cv. Boma in greenhouse experiments. Roots from salt-treated plants (0·2 mol l–1 NaCl) were smaller than controls, and accumulated higher concentrations of soluble sugars and reserve lipids. The number of nodal roots was reduced by the saline treatment. Leaf, tiller and nodal root appearance were delayed by salinity but the correlation among these processes was maintained, indicating that the developmental pattern was not altered by this level of salinity, only its rate. Initial nodal root growth rates varied as a function of plant size and were decreased by salinity only after 2 weeks of treatment. When shoots of non-salinized plants were cut, a drastic reduction in nodal root appearance was observed, suggesting emerging leaves were stronger sinks than roots for available reserves. However, when the shoots of salt-treated plants were cut, the already depressed root appearance rate was not further reduced. This suggests that, under salinity, alterations in root ability to metabolize reserves could have been more significant than reserve availability for controlling elongation. 相似文献
7.
J. M. Zabala E. Taleisnik J. A. Giavedoni J. F. Pensiero G. E. Schrauf 《Grass and Forage Science》2011,66(1):109-122
Elymus scabrifolius is a native C3 South American grass species. It is valued as forage species adapted to various environments in Argentina and is also a potential source of traits for wheat‐breeding programmes. Efficient utilization of native genetic resources requires extensive collection and characterization of available material. The purpose of this study was to identify and characterize variability in salt tolerance within E. scabrifolius populations in Argentina. Specimens of E. scabrifolius were collected from a wide range of soils in Argentina, and most populations were found in saline environments with high sodium levels. Intraspecific variability in salt tolerance was estimated, and its relation to the salinity level of the populations’ natural environment was assessed. A principal component analysis based on growth data distinguished lines from saline and non‐saline habitats only under salt conditions. Results suggest that selecting under stressed environments is a reasonable strategy for breeding E. scabrifolius. Lines of saline origin had higher biomass under both control and saline conditions, suggesting that higher gains from selection would be obtained if germplasm from this origin was used, and tillering may be the most useful indirect selection criterion for improving salt tolerance. The association between salt tolerance, ion content and osmotic adjustment was also assessed. Salt‐sensitive lines accumulated high sodium levels in leaves. However, osmotic adjustment did not correlate with the maintenance of leaf elongation rates under salinity in the genotypes included in this study. 相似文献
8.
C. Bruno A. Tomás D. Bustos M. Monteoliva L. Ortega E. Taleisnik 《Grass and Forage Science》2016,71(4):683-698
This work assessed intracultivar variability for salt tolerance within Panicum coloratum cv. Klein, explored some physiological parameters potentially associated with it and evaluated the contribution of cell division and expansion to the decreased leaf length observed under salinity. Individual plants that had survived severe stress environments in an established pasture were collected and clonal families were obtained by vegetative propagation. These were evaluated in a greenhouse, in pots with an inert substrate irrigated with nutrient solution containing 0, 200 or 400 mm NaCl. Salt tolerance was assessed from growth variables expressed as a percentage of non‐salinized controls. Changes induced by salinity in carbon fixation, soluble sugars and compatible solutes were also measured. The selected plants showed 33% higher salt tolerance than plants from the same cultivar obtained from seeds, and variability for salt tolerance was detected within the group, suggesting these plants could be valuable germplasm for breeding programmes for saline areas. All selected plants accumulated low leaf blade Na concentrations (< 0·1 mm g?1 dry weight on average), and K concentrations tended to remain high under salinity. A kinematic analysis indicated a reduction in the number of cells in the division‐only zone was the main cause of shorter leaves under stress. Although plants showed some differences in all these traits, they were not related to salt‐tolerance variability within this group of stress‐tolerant plants. 相似文献
9.
Salinity effects on the early development stages of Panicum coloratum: cultivar differences 总被引：2，自引：0，他引：2
Taleisnik Pérez Córdoba Moreno L. García Seffino Arias Grunberg Bravo & Zenoff 《Grass and Forage Science》1998,53(3):270-278
The Argentinean semiarid Chaco region is climatically suitable for cattle raising and has an average annual rainfall of 550 mm, concentrated from November to February. There, large areas are affected by high salinity; thus, perennial forages suitable for this region must combine adequate salt and drought tolerance. Panicum coloratum is a C4 perennial grass adapted over a wide range of soil and rainfall conditions, and the purpose of this study was to evaluate the response of two cultivars (Klein Verde and Bambatsi) to salinity. Under controlled conditions, 100 and 200 mmol l−1 NaCl delayed germination and significantly reduced germination percentages and seedling survival in both cultivars. However, in the field, factors other than salinity (possibly drought) had a large impact on plant survival. In short-term experiments under controlled environmental conditions, the vegetative growth of cultivar Klein Verde was less affected by salinity than Bambatsi. The cumulative growth over one year in a saline plot was also higher in cultivar Klein Verde. This cultivar also had higher shoot K+ /Na+ ratios under salinity, as a result of higher K+ concentrations, and accumulated more triglycerides in roots. These features have been associated with salt tolerance in other species. 相似文献
10.
Nutrient deficiency and hypoxia as constraints to Panicum coloratum growth in alkaline soils 
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下载免费PDF全文 D. F. Luna A. Aguirre G. Pittaro D. Bustos B. Ciacci E. Taleisnik 《Grass and Forage Science》2017,72(4):640-653
Alkaline and saline–alkaline soils impose severe restrictions on plant growth. Panicum coloratum var. coloratum is a perennial C4 forage grass widely used in tropical and subtropical environments. Published information on its responses to alkaline soil conditions is scarce. The objectives of this study were (i) to characterize the effects of alkaline substrates on germination and initial growth in this species, (ii) to assess the influence of high pH in combination with reduced availability of either nutrients or oxygen and salinity, on plant growth and (iii) to evaluate some physiological traits potentially responsible for growth restrictions under alkaline soil conditions. Trials were conducted in a greenhouse. Germination and early plant survival were not affected by alkalinity. To isolate the effects of high pH, reduced nutrient and oxygen availability on growth, plants were grown either in neutral or alkaline soil, in hydroponics, in neutralized alkaline soil (with or without supplementary fertilization), or were flooded to induce hypoxia. Alkalinity effects on growth in hydroponics were milder than in soil. Growth in alkaline soil with nutrient supplement was still significantly lower (by 40%) than in neutral soil. Both alkalinity and hypoxia reduced growth non‐synergistically. These results show that studies of plant response to alkaline substrates carried out in aerated nutrient solutions can only partially address the complexity of this stress. Photosynthesis and PSII activity were among the physiological mechanisms negatively affected by alkalinity and may be partially responsible for the growth limitations observed in P. coloratum under alkaline conditions. 相似文献