The endogenous levels of auxin and cytokinin in teratoma and unorganized tobacco (Nicotiana tabacum L. var Wisconsin #38) crown gall tumor tissues were determined. Teratoma tissues contain levels of auxin and cytokinin favorable for shoot formation, whereas unorganized tumors contain levels of auxin that suppress shoot formation. This conclusion is based upon the observation that when levels of...

Regeneration, a remarkable example of developmental plasticity displayed by both plants and animals, involves successive developmental events driven in response to environmental cues. Despite decades of study on the ability of the plant tissues to regenerate a complete fertile shoot system after inductive cues, the mechanisms by which cells acquire pluripotency and subsequently regenerate compl...

Despite the wide use of plant regeneration for biotechnological purposes, the signals that allow cells to become competent to assume different fates remain largely unknown. Here, it is demonstrated that the Regeneration1 (Rg1) allele, a natural genetic variation from the tomato wild relative Solanum peruvianum, increases the capacity to form both roots and shoots in vitro; and that the gibberel...

Foliar NH4(+) exposure is linked to inhibition of lateral root (LR) formation. Here, the role of shoot ethylene in NH4(+)-induced inhibition of LR formation in Arabidopsis was investigated using wild-type and mutant lines that show either blocked ethylene signalling (etr1) or enhanced ethylene synthesis (eto1, xbat32). NH4(+) exposure of wild-type Arabidopsis led to pronounced inhibition of LR ...

This experiment was performed to optimize the medium for tissue culture of Taraxacum kok-saghyz Rodin. Different tissue culture approaches such as shoot regeneration from seed, callus formation from leaf explants and plant regeneration from callus were investigated in this study. All the explants were cultured on MS basal medium supplemented with 20g/l sucrose, 7g/l agar and different plant gro...

Different explants of Crocus sativus L. such as corm, style, ovary, petal, anther and leaf were cultured on LS and MS media supplemented with NAA and BAP or 2,4-D plus BAP at different combinations. Shoot and corm induction occurred in addition to the formation of other organs. Efficient plantlet regeneration with strong roots occurred at 1 mg 1-I of both NAA and BAP. An increase in 2,4-D l...

different explants of crocus sativus l. such as corm, style, ovary, petal, anther and leaf were cultured on ls and ms media supplemented with naa and bap or 2,4-d plus bap at different combinations. shoot and corm induction occurred in addition to the formation of other organs. efficient plantlet regeneration with strong roots occurred at 1 mg 1-i of both naa and bap. an increase in 2,4-d level...