Wyniki wyszukiwania - Biblioteka Nauki

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Maize seed cryo-storage modifies chlorophyll, carotenoid, protein, aldehyde and phenolics levels during early stages of germination

100%

Arguedas M. , Gomez D. , Hernandez L. , Engelmann F. , Garramone R. , Cejas I. , Yabor L. , Martinez-Montero M. E. , Lorenzo J. C.

Acta Physiologiae Plantarum

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2018

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tom 40

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nr 06

2

Biochemical and physiological changes produced by Azotobacter chroococcum (INIFAT5 strain) on pineapple in vitro-plantlets during acclimatization

100%

Gonzalez-Rodriguez R. M. , Serrato R. , Molina J. , Aragon C. E. , Olalde V. , Pulido L. E. , Dibut B. , Lorenzo J. C.

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nr 12

EN

This study highlights some of the effects of the application of Azotobacter chroococcum (INIFAT5 strain) on in vitro-pineapple plantlets during acclimatization. The bacteria were sprayed immediately after transplanting to the ex vitro environment; the plants were then sprayed every 4 week. Subsequently (4 months) the evaluated variables included plantlet fresh and dry weights, leaf and root lengths, and composition of minerals, amino-acids, carbohydrates and proteins. Photosynthesis indicators were also evaluated. Significant effects of the application of Azotobacter over pineapple plantlets during acclimatization were observed in the mineral, amino-acid, carbohydrate and protein levels, as well as, in the photosynthesis indicators. Contrastingly, plant growth parameters showed modest increases caused by the bacteria, although they were statistically significant. Looking into specific minerals, the following significant effects of Azotobacter should be highlighted: increased levels of nitrogen, phosphorous, potassium, magnesium, copper and zinc. Moreover, contents of all amino-acids recorded showed significant increases in their levels in sprayed plantlets. Carbohydrates were also increased in leaves of plantlets bio-fertilized with the bacteria, mainly sucrose and fructose. Chlorophyll b levels were also significantly increased by Azotobacter. The biofertilizer did not modify levels of calcium, iron or manganese.

3

Sodium azide mutagenesis within temporary immersion bioreactors modifies sugarcane in vitro micropropagation rates and aldehyde, chlorophyll, carotenoid, and phenolic profiles

100%

Gomez D. , Hernandez L. , Martinez J. , Escalante D. , Zevallos B. E. , Yabor L. , Trethowan R. , Beemster G. T. S. , Sershen , Lorenzo J. C.

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2019

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tom 41

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nr 07

EN

Chemical mutagens such as sodium azide (NaN₃) have been widely used to increase genetic variability in crops, but the undirected mutations induced can have undesirable effects, which need to be characterized. This study investigated the effects of in vitro NaN₃ (0–0.45 mM) exposure (30 days) on the micropropagation of sugarcane within temporary immersion bioreactors (TIB). Shoot multiplication rate and cluster fresh weight, and aldehyde, phenolic, carotenoid, and chlorophyll levels were measured on in vitro produced shoots. The soluble phenolic content of the culture medium was also assessed. NaN₃ concentration was negatively correlated with sugarcane shoot multiplication rate and fresh weight; at 0.45 mM NaN₃, these parameters were only 20% and 39% that of the untreated control, respectively. Shoot multiplication rate and fresh weight, and chlorophyll a and b levels were negatively correlated with NaN₃ concentration. In contrast, malondialdehyde, other aldehyde, carotenoid, and exuded phenol levels were positively correlated with NaN₃ concentration. Statistical comparisons suggest that shoot multiplication rate and the biochemical parameters that were positively correlated with NaN₃ concentration may be the most suitable indicators of stress when optimizing the concentration of NaN₃ for sugarcane explants. An interpolated 50% reduction of multiplication rates at 0.23 mM NaN₃ suggests that this concentration to be suitable for TIB-based induction of mutagenesis in shoots and eventual production of agriculturally useful mutants.

4

Micropropagation of Hohenbergia penduliflora (A. Rich.) Mez. for sustainable production of plant proteases

80%

Perez A. , Laudat T. , Mora M. , Carvajal C. , Aragon C. , Gonzalez J. , Escalona M. , Daquinta M. , Trujillo R. , Hernandez M. , Lorenzo J. C.

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nr 08

EN

Hohenbergia penduliflora (A. Rich.) Mez. inhabits the protected ecological area of Cunagua Highland, Ciego de Ávila, Cuba. The availability of this plant for experimental purposes is exceedingly limited. Tissue cultured plants of this specie, would be useful for propagation purposes. Experiments were carried out to optimize the micropropagation process from the disinfection of fruits to ex vitro hardening of regenerated plantlets. The best results were obtained when seeds were disinfected with 2 % (v:v) sodium hypochlorite for 20 min and placed in vitro for 45 days for seed germination. Tissue cultured shoots (1 cm) with vertical wounds in the basal region (5 mm long) were placed in a medium containing Murashige and Skoog (MS) salts, 100 mg l-1 myo-inositol, 0.1 mg l-1 thiamine-HCl, 30 g l-1 sucrose, 8.8 lM 6-benzyladenine (BA) and 1.6 μM naphthalene acetic acid (NAA). Shoots were proliferated for 45 days to obtain 8.21 new shoots per explant; they were subsequently divided and rooted on a medium containing 1.6 μM NAA for 30 days. For ex vitro hardening, plastic trays containing 82 cm3 of filter-cake-sugarcane ashes were used; 100 % survival rate was recorded. After 6 months of hardening, plants were established ex vitro and ready for protease extraction. Comparisons between protein contents, proteolytic activities and specific proteolytic activities of extracts from stems of macro- and micropropagated plants were acquired. Tissue cultured stems showed statistically lower figures which is why Ethrel was tested here to increase proteolytic activity in micropropagated plant stems. After Ethrel applications, protein contents, proteolytic activities and specific proteolytic activities of extracts from stems were the three main indicators recorded. However, other biochemical effects of Ethrel were also evaluated, such as, levels of chlorophyll pigments, malondialdehyde and other aldehydes; and superoxide dismutase, and guaiacol peroxidase activities. Rising concentrations of Ethrel (0, 1.5, 3.0, 4.5 and 6.0 mg l-1) decreased protein contents at 72 h but increased proteolytic and specific proteolytic activities of stem extracts. Ethrel was effective in increasing proteolytic activity in in vitro culture-derived plant stems, at a level higher than in fieldgrown plant stems. Moreover, Ethrel increased superoxide dismutase and guaiacol peroxidase-specific activities in leaves; and decreased chlorophyll pigments. Ethrel did not affect levels of malondialdehyde and other aldehydes.

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Effects of Teramnus labialis (L.f.) Spreng seed cryopreservation on subsequent seed and seedling growth and biochemistry

80%

Acosta J. , Perez L. , Linares C. , Hernandez L. , Escalante D. , Perez A. , Zevallos B. E. , Yabor L. , Martinez-Montero M. E. , Cejas I. , Fontes D. , Sershen , Lorenzo J. C.

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tom 42

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nr 01