The aim of this study was to investigate the effects of concentration of different growth regulators (auxins and cytokinins) on growth and development of banana shoot tips cultured in vitro. Explants were taken from y...The aim of this study was to investigate the effects of concentration of different growth regulators (auxins and cytokinins) on growth and development of banana shoot tips cultured in vitro. Explants were taken from young suckers of field grown plants of var. “Yangambi”. The shoot tips were cultured on MS media supplemented with different concentrations of BAP (0, 2, 4, 6 and 8 mg/l) with or without IAA at concentration of 0.34 mg/l. At the rooting phase, the media was supplemented with different concentrations of IBA (0.1, 0.5, 1.0, 1.5 and 2.0 mg/l) with or without BAP at concentration of 0.2 mg/l. The results indicated that 6.0 mg/l BAP significantly increased the number of shoots formed and the interaction of 6 mg/l BAP with 0.35 mg/l IAA significantly increased the fresh weight. For rooting, 2.0 mg/l IBA was more efficient in number and length of roots produced than all other treatments.展开更多
A study was done to produce a rapid in vitro propagation of three strawberry genotypes and tested in the field under Bangladeshi circumstances. Festival, RABI-3, and Neho strawberry genotypes’ runner tips were cultiv...A study was done to produce a rapid in vitro propagation of three strawberry genotypes and tested in the field under Bangladeshi circumstances. Festival, RABI-3, and Neho strawberry genotypes’ runner tips were cultivated in vitro to induce root induction and multiple shoot proliferation. MS (Murashige and Skoog) media that were basally containing three different concentrations at 1.0, 1.5, and 2.0 of BA (6-benzyl adenine), KIN (6-furfuryl amino purine), or GA<sub>3</sub> (gibberellic acid) at 0.5 mg/L increasing tips of the runner was attained. The culture grew on the medium provided with 1.5 mg/L 6-benzyl adenine and 0.5 mg/L 6-furfuryl amino acid to increase shoot at the best level. Micro-cuttings were rooted on MS media at half strength combined with 0.5 mg/L - 1.5 mg/L IBA (indole butyric acid) or IAA (indole acetic acid). IBA attained 4 - 9 roots and 91% - 96% rooting at 1.0 mg/L. The resulting plantlets grew into hardy plants and took root in the earth. The genotype festival had the highest response rate, followed by RABI-3 and Neho.展开更多
At the Genetics and Plant Breeding Laboratory of the Department of Agronomy and Agricultural Extension, University of Rajshahi, Bangladesh, strawberry in vitro propagation was done. Five Benzylaminopurine (BAP) concen...At the Genetics and Plant Breeding Laboratory of the Department of Agronomy and Agricultural Extension, University of Rajshahi, Bangladesh, strawberry in vitro propagation was done. Five Benzylaminopurine (BAP) concentrations were utilized for shoot induction—0.0 mg/L (Control), 0.5 mg/L, 1.0 mg/L, 1.5 mg/L, and 2.0 mg/L and five Indole Buteric Acid (IBA) concentrations—0.0 mg/L(Control), 0.5 mg/L, 1.0 mg/L, 1.5 mg/L, and 2.0 mg/l—were used for the induction of the root. The highest mean amount of shoots (eight) and length of the shoot (3.40 cm) were observed at a concentration of BAP of 0.5 mg/L. Festival also had the highest mean amount of leaves (6) when we used the identical concentration, while RABI-3 and Camarosa did the least well. The IBA of 0.5 mg/L concentration of rooting performed the best across all metrics tested among the five concentrations. The longest (3.3 cm) roots and most roots (7) were likewise obtained from this concentration in Festival. However, RABI-3 and Camarosa performed worse than Festival in the same concentration. Half-strength MS media without IBA concentration showed no response regarding root induction for each of the three cultivars.展开更多
Cytokinin and nitric oxide （NO） have been characterized as signaling molecules to trigger cell division in tissue culture. Here, we show that the hypocotyl and root explants of Arabidopsis NO-deficient mutant nosl/n...Cytokinin and nitric oxide （NO） have been characterized as signaling molecules to trigger cell division in tissue culture. Here, we show that the hypocotyl and root explants of Arabidopsis NO-deficient mutant nosl/noal exhibit severe defects in callus induction and shoot regeneration in response to cytokinin. Accordingly, depletion of NO caused by a NO scavenger leads to a severe inhibitory effect on callus induction. Moreover, cytokinin-induced NO production is impaired in nosl/noal in which cytokinin-triggered activation of cell cycle gene CYCD3;1 is inhibited, indicating that NO may act downstream of cytokinin in the control of cell proliferation through CYCD3;1. This hypothesis is further con- firmed by the genetic evidence that constitutive expression of CYCD3;1 complements the defects of nosl/noal mutant in meristematic activity in shoot, root, and floral tissues as well as in cytokinin-induced callus initiation and shoot regen- eration. Furthermore, we show that NO deficiency caused by loss of NOSl/NOA1 impairs cellular development such as the duration of the mitotic phase and timing of the transition to endocycles in nosl/noal mutant leaves, which can be reverted by constitutive expression of CYCD3;1. Taken together, these results demonstrate that NO mediates transcrip- tional activation of CYCD3,1 in regulating the mitotic cycles in response to cytokinins.展开更多
This research reports on an efficient shoot proliferation and callus regeneration system for bamboo.Young, semi-lignified branches with one lateral bud from Drepanostachyum luodianense(Yi et R. S. Wang) Keng f.were us...This research reports on an efficient shoot proliferation and callus regeneration system for bamboo.Young, semi-lignified branches with one lateral bud from Drepanostachyum luodianense(Yi et R. S. Wang) Keng f.were used as explants. Disinfection with 0.1% HgCl2 for 8 min was the optimum treatment and the best medium for bud initiation was Murashige and Skoog(MS) medium containing 3.0 mg L-16-benzyladenine(BA). Multiple shoots were induced from nodal shoot segments on MS medium containing 5.0 mg L-1 BA, 0.5 mg L-1 kinetin(Kin), and 1.0 mg L-1 naphthaleneacetic acid(NAA). The highest frequency of callus formation(65.6%) was on MS medium containing 4.0 mg L-12,4-dichlorophenoxyacetic acid(2, 4-D), 0.5 mg L-1 NAA, and 0.1 mg L-1 thidiazuron(TDZ). The optimum medium for callus proliferation was MS medium with 4 mg L-12,4-D, 0.5 mg L-1 TDZ and 0.5 mg L-1 NAA, and the optimum hormone combination was 4 mg L-1 BA ? 0.5 mg L-1 NAA for callus redifferentiation(up to 85.6%). A 100% rooting was achieved on MS medium supplemented with 2.0 mg L-1 NAA and 0.5 mg L-13-indole butyric acid(IBA). Rooted plantlets were acclimatized in a greenhouse in humus soil ? perlite(1:1) substrate. These micropropagated callus induction and regeneration systems for bamboo will be useful for genetic engineering and multiplication.展开更多
文摘The aim of this study was to investigate the effects of concentration of different growth regulators (auxins and cytokinins) on growth and development of banana shoot tips cultured in vitro. Explants were taken from young suckers of field grown plants of var. “Yangambi”. The shoot tips were cultured on MS media supplemented with different concentrations of BAP (0, 2, 4, 6 and 8 mg/l) with or without IAA at concentration of 0.34 mg/l. At the rooting phase, the media was supplemented with different concentrations of IBA (0.1, 0.5, 1.0, 1.5 and 2.0 mg/l) with or without BAP at concentration of 0.2 mg/l. The results indicated that 6.0 mg/l BAP significantly increased the number of shoots formed and the interaction of 6 mg/l BAP with 0.35 mg/l IAA significantly increased the fresh weight. For rooting, 2.0 mg/l IBA was more efficient in number and length of roots produced than all other treatments.
文摘A study was done to produce a rapid in vitro propagation of three strawberry genotypes and tested in the field under Bangladeshi circumstances. Festival, RABI-3, and Neho strawberry genotypes’ runner tips were cultivated in vitro to induce root induction and multiple shoot proliferation. MS (Murashige and Skoog) media that were basally containing three different concentrations at 1.0, 1.5, and 2.0 of BA (6-benzyl adenine), KIN (6-furfuryl amino purine), or GA<sub>3</sub> (gibberellic acid) at 0.5 mg/L increasing tips of the runner was attained. The culture grew on the medium provided with 1.5 mg/L 6-benzyl adenine and 0.5 mg/L 6-furfuryl amino acid to increase shoot at the best level. Micro-cuttings were rooted on MS media at half strength combined with 0.5 mg/L - 1.5 mg/L IBA (indole butyric acid) or IAA (indole acetic acid). IBA attained 4 - 9 roots and 91% - 96% rooting at 1.0 mg/L. The resulting plantlets grew into hardy plants and took root in the earth. The genotype festival had the highest response rate, followed by RABI-3 and Neho.
文摘At the Genetics and Plant Breeding Laboratory of the Department of Agronomy and Agricultural Extension, University of Rajshahi, Bangladesh, strawberry in vitro propagation was done. Five Benzylaminopurine (BAP) concentrations were utilized for shoot induction—0.0 mg/L (Control), 0.5 mg/L, 1.0 mg/L, 1.5 mg/L, and 2.0 mg/L and five Indole Buteric Acid (IBA) concentrations—0.0 mg/L(Control), 0.5 mg/L, 1.0 mg/L, 1.5 mg/L, and 2.0 mg/l—were used for the induction of the root. The highest mean amount of shoots (eight) and length of the shoot (3.40 cm) were observed at a concentration of BAP of 0.5 mg/L. Festival also had the highest mean amount of leaves (6) when we used the identical concentration, while RABI-3 and Camarosa did the least well. The IBA of 0.5 mg/L concentration of rooting performed the best across all metrics tested among the five concentrations. The longest (3.3 cm) roots and most roots (7) were likewise obtained from this concentration in Festival. However, RABI-3 and Camarosa performed worse than Festival in the same concentration. Half-strength MS media without IBA concentration showed no response regarding root induction for each of the three cultivars.
基金This research was supported in parts by the Ministry of Science and Technology of China，the Ministry of Agriculture of China，the National Natural Science Foundation of China，the CAS/SAFEA International Partnership Program for Creative Research Teams
文摘Cytokinin and nitric oxide （NO） have been characterized as signaling molecules to trigger cell division in tissue culture. Here, we show that the hypocotyl and root explants of Arabidopsis NO-deficient mutant nosl/noal exhibit severe defects in callus induction and shoot regeneration in response to cytokinin. Accordingly, depletion of NO caused by a NO scavenger leads to a severe inhibitory effect on callus induction. Moreover, cytokinin-induced NO production is impaired in nosl/noal in which cytokinin-triggered activation of cell cycle gene CYCD3;1 is inhibited, indicating that NO may act downstream of cytokinin in the control of cell proliferation through CYCD3;1. This hypothesis is further con- firmed by the genetic evidence that constitutive expression of CYCD3;1 complements the defects of nosl/noal mutant in meristematic activity in shoot, root, and floral tissues as well as in cytokinin-induced callus initiation and shoot regen- eration. Furthermore, we show that NO deficiency caused by loss of NOSl/NOA1 impairs cellular development such as the duration of the mitotic phase and timing of the transition to endocycles in nosl/noal mutant leaves, which can be reverted by constitutive expression of CYCD3;1. Taken together, these results demonstrate that NO mediates transcrip- tional activation of CYCD3,1 in regulating the mitotic cycles in response to cytokinins.
基金supported by the National Key Research and Development Program of China under Grant2016YFD0600901Jiangsu Province ‘‘SANXIN’’ Support Project under Grant LYSX [2016]04+1 种基金National Natural Science Foundation for Young Scholars of China under Grant 31000294Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘This research reports on an efficient shoot proliferation and callus regeneration system for bamboo.Young, semi-lignified branches with one lateral bud from Drepanostachyum luodianense(Yi et R. S. Wang) Keng f.were used as explants. Disinfection with 0.1% HgCl2 for 8 min was the optimum treatment and the best medium for bud initiation was Murashige and Skoog(MS) medium containing 3.0 mg L-16-benzyladenine(BA). Multiple shoots were induced from nodal shoot segments on MS medium containing 5.0 mg L-1 BA, 0.5 mg L-1 kinetin(Kin), and 1.0 mg L-1 naphthaleneacetic acid(NAA). The highest frequency of callus formation(65.6%) was on MS medium containing 4.0 mg L-12,4-dichlorophenoxyacetic acid(2, 4-D), 0.5 mg L-1 NAA, and 0.1 mg L-1 thidiazuron(TDZ). The optimum medium for callus proliferation was MS medium with 4 mg L-12,4-D, 0.5 mg L-1 TDZ and 0.5 mg L-1 NAA, and the optimum hormone combination was 4 mg L-1 BA ? 0.5 mg L-1 NAA for callus redifferentiation(up to 85.6%). A 100% rooting was achieved on MS medium supplemented with 2.0 mg L-1 NAA and 0.5 mg L-13-indole butyric acid(IBA). Rooted plantlets were acclimatized in a greenhouse in humus soil ? perlite(1:1) substrate. These micropropagated callus induction and regeneration systems for bamboo will be useful for genetic engineering and multiplication.
