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91.
92.
93.
A plant growth promoting rhizobacterium and temperature effects on performance of 18 clones of potato 总被引:1,自引:0,他引:1
A survey of genotypic responses to beneficial bacterium (Pseudomonas sp. strain PsJN) was conductedin vitro andex vitro, under two temperature conditions, using eighteen clones of potato of different heat stress tolerance: temperate adapted cultivars Kennebec and Russet Burbank; heat tolerant DTO-2, DTO-28, DTO-33, LT-1, LT-2, LT-5, LT-6, LT-7, LT-8, LT-9, Y84-02, NDD277-2, Désirée, and Maine-47; and heat sensitive abscissic acid (ABA)-deficient mutants 11401-01 and 9120-05. Nodal explants taken from 6-week-old bacterized and non-bacterized control plantlets were culturedin vitro on a hormone-free potato nodal cutting medium, and placed at either 20/15 C or 33/25 C day/night temperature, 12h photoperiod and 250 µE m?2 s?1 mixture of fluorescent and incandescent light, for six weeks. The tuberization response was studiedex vitro after two weeks acclimation of 2-week old plantlets at 33/25C. The acclimated plantlets were transplanted to 3L plastic nursery pots containing peat-based Pro-Mix growing medium and placed in growth chambers at either 20/15 or 33/25 C day/night temperature, 12 h photoperiod, 475 μE m?2 s?1 light and ≈80% RH, for 12 weeks. Compared to the non-bacterized controls, bacterization significantly increased stem length of 12, shoot biomass of 9, and root biomass of 2 clones at 20/15C; and stem length of 14, shoot biomass of 15, and root biomass of 13 clones at 33/25C. High temperature increased length of internodes and had either no effect or slightly decreased node number. Temperature increase had the most dramatic effect on root development. An average shoot to root ratio decreased from 3.7 at 20/15 C to 1.7 at 33/25 C for non-bacterized plantlets and, respectively, from 4.3 to 1.5 for bacterized. The beneficial effect of bacterization on root biomass was the most pronounced in LT-1 and Maine-47 at 20/15 C and LT-8, Maine 47, DTO-2, Kennebec, NDD277-2 and 11401-01 at 33/25C. The temperature elevation did not significantly affect root biomass of LT-6, DTO-28 and Désirée. Temperature stress caused severe reduction in tuber number and tuber fresh weight. ABA-deficient mutants did not produce any tubers and LT-8, LT-9, Y84-027 and DTO-28 tuberized very poorly at 33/25C. DTO-33, Désirée, LT-1 and Kennebec gave the highest number of tubers per pot and Kennebec, LT-1, Désirée and LT-7 the highest yields at this temperature. There was no significant effect of bacterization on tuberization at 20/15 C but at 33/25 C bacterization significantly enhanced tuber number and weight in LT-7 and reduced tuber weight in DTO-2. Although there was no clear link between thein vitro response of particular clones to bacterization and their heat stress tolerance, improvement ofex vitro performance of heat tolerant LT-7 indicates that rhizosphere bacteria may play a role in clonal adaptation of potato to heat stress. 相似文献
94.
Individual size, size variability, cannibalism, total mortality and biomass production were studied in Clarias gariepinus in two experiments. In the Experiment 1st (duration 7 weeks) larvae originated from three females 1, 2 and 4 years old (females A, B and C, respectively). Three sibling (AA, BB and CC) and three mixed (AB, AC and BC, 1:1) larval groups were reared at a 12L:12D, 50 lux light regime. Initial individual weight of larvae in the sibling groups was strongly positively related to female age, this was preserved during 7 weeks of rearing. Initial coefficient of variation for weight was moderate in the sibling groups from young females AA and BB (30-33%), whereas it was elevated in the mixed groups (48-79%), especially in the group AC. Cannibalism was the major component of total mortality. Cannibalism in progeny of young females AA, AB and BB was reduced compared to the groups BC, AC and CC. Final biomass of small larvae issued from young females was higher than the final biomass of large progeny of the oldest female because of reduced cannibalism in the former. In a 6 week Experiment 2nd progeny of one female was reared at three light regimes: L (continuous light, 400 lux), N (“normal” 12L:12D, 50 lux) and D (continuous darkness). The final individual weight of fish was the lowest in the L group, highest in the D group, and intermediate in the N group. Final coefficient of variation for weight, cannibalism and total mortality were significantly reduced by light restrictions. The resulting final biomass was the lowest in the L group, intermediate in the N group and the highest in the D group in which it was higher by a factor 3.8 compared to the L group. Based on the results of present work and on literature overview several pathways were identified along which biomass size may be modified in populations of young fish that exhibit cannibalistic propensity. Selection of young female spawners of uniform age, and light restrictions, are recommended to mitigate cannibalism. 相似文献
95.
The organic fraction of municipal wastes has been composted on the laboratory scale. In the obtained compost the content of cadmium, cobalt, copper, manganese, nickel, lead and zinc were determined, as well as the speciation i.e, the form of their occurrence, making use of Rudd's method of sequential extraction. The investigations also concerned the way of removing these metals from the compost by means of leaching with solutions of sulphuric and nitric acid, as well as by electrochemically separating the metals from the solution after the compost had been leached with sulphuric acid. It has been found that the application of the electrochemical method with varying pH values of the leaching solution within the range of 6.8–2.8 allows for the separation of 83.5% Cd, 55.0% Co, 65.4% Cu, 59.4% Mn, 70.3% Ni, 90.5% Pb and 56.2% Zn. 相似文献
96.
Krzysztof Kucypera Marcin Lipowczan Anna Piekarska-Stachowiak Jerzy Nakielski 《Plant methods》2017,13(1):110
Background
The development of cell pattern in the surface cell layer of the shoot apex can be investigated in vivo by use of a time-lapse confocal images, showing naked meristem in 3D in successive times. However, how this layer is originated from apical initials and develops as a result of growth and divisions of their descendants, remains unknown. This is an open area for computer modelling. A method to generate the surface cell layer is presented on the example of the 3D paraboloidal shoot apical dome. In the used model the layer originates from three apical initials that meet at the dome summit and develops through growth and cell divisions under the isotropic surface growth, defined by the growth tensor. The cells, which are described by polyhedrons, divide anticlinally with the smallest division plane that passes depending on the used mode through the cell center, or the point found randomly near this center. The formation of the surface cell pattern is described with the attention being paid to activity of the apical initials and fates of their descendants.Results
The computer generated surface layer that included about 350 cells required about 1200 divisions of the apical initials and their derivatives. The derivatives were arranged into three more or less equal clonal sectors composed of cellular clones at different age. Each apical initial renewed itself 7–8 times to produce the sector. In the shape and location and the cellular clones the following divisions of the initial were manifested. The application of the random factor resulted in more realistic cell pattern in comparison to the pure mode. The cell divisions were analyzed statistically on the top view. When all of the division walls were considered, their angular distribution was uniform, whereas in the distribution that was limited to apical initials only, some preferences related to their arrangement at the dome summit were observed.Conclusions
The realistic surface cell pattern was obtained. The present method is a useful tool to generate surface cell layer, study activity of initial cells and their derivatives, and how cell expansion and division are coordinated during growth. We expect its further application to clarify the question of a number and permanence or impermanence of initial cells, and possible relationship between their shape and oriented divisions, both on the ground of the growth tensor approach.97.
Summary Seedlings from Canadian alfalfa cultivars Algonquin and Apica were selected on the basis of ability to regenerate plants from hypocotyl callus. A total of eleven genotypes were selected, resulting in regeneration frequencies of 4.5 and 11.7% for Algonquin and Apica, respectively. Regeneration capacity within these cultivars was also compared with cultivars and breeding lines for which regeneration frequencies have previously been documented. Two genotypes (A1 93 and Ap 20) exhibited prolific embryogenesis from hypocotyl and petiole callus and also regenerated plants from suspension culture. Flowering and seed set have been observed for regenerated plants. 相似文献
98.
Jurgoński A Juśkiewicz J Zduńczyk Z 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(4):176-182
This report presents a complex analysis of changes proceeding in the gut, blood and internal organs of rats with induced oxidative
stress, glucose intolerance and hyperlipidemia after dietary supplementation with an extract from black chokeberry (Aronia melanocarpa) fruit, that is a condensed source of polyphenols (714 mg/g), especially anthocyanin glycosides (56.6%). The disturbances
mimicking those observed in metabolic syndrome were induced by a high-fructose diet and simultaneous single injection of streptozotocin
(20 mg/kg). Dietary supplementation with the chokeberry fruit extract (0.2%) decreased activity of maltase and sucrase as
well as increased activity of lactase in the mucosa of the small intestine. Its ingestion led also to the improvement of antioxidant
status, especially, the concentration of a lipid peroxidation indicator (TBARS) in organ tissues (liver, kidney and lung)
was normalized; some cholesterol-lowering and distinct hypoglycemic actions were also observed. The mechanism of glucose reduction
is likely to be multifactorial, and we suggest the factors related with the decreased activity of mucosal disaccharidases
important for further investigation. In conclusion, chokeberry fruit derivatives may act as a promising supplementary therapeutic
option in the prevention and treatment of disorders occurring in metabolic syndrome, as well as their complications. 相似文献
99.
Szwagrzyk Jerzy Gazda Anna Zwijacz-Kozica Tomasz Zięba Antoni Ciesielska Barbara Szewczyk Janusz Foremnik Kacper Muter Elżbieta Bodziarczyk Jan 《European Journal of Forest Research》2021,140(4):835-845
European Journal of Forest Research - The relative importance of environmental factors and species pool in natural regeneration processes is still intensively disputed. Is environmental filtering... 相似文献
100.
Kosmala M Kołodziejczyk K Zduńczyk Z Juśkiewicz J Boros D 《Journal of agricultural and food chemistry》2011,59(17):9177-9185
Unprocessed pomace containing 61% of dietary fiber (DF) and 0.23% of polyphenols (PP) and ethanol- or ethanol/acetone-extracted pomaces containing 66% DF and 0.10% PP and 67% DF and 0.01% PP, respectively, were subjected to a 4 week study in rats. The aim of the study was assessing the advantages of dietary supplementation with the above pomaces. To measure the animal response to dietary treatments, parameters describing cecal fermentation and lipoprotein profile were assessed. The dietary use of 5% unprocessed pomace caused an increase in cecal short-chain fatty acid (SCFA) production and a decrease in blood triacylglycerols, leading to a drop in serum atherogenic index. Ethanol-extracted pomace increased the glycolytic activity of cecal microbiota and decreased cecal branched-chain fatty acid production, whereas acetone extraction led to lower cecal ammonia concentration, decreased colonic pH value, and higher HDL/total cholesterol ratio. The variations in the atherogenic index indicate flavonoids as the key pomace component in relation to blood lipid profile benefits. 相似文献