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Interactive effects of gibberellic acid, cytokinin-like compounds, sucrose and daylength on in vitro tuberization of potato (Solanum tuberosum L.) and influences of cytokinin-like compounds of invertase activity during microtuberization
Abstract
Factors controlling microtuberization were investigated using in vitro-derived plantlets of potato, Solanum tuberosum L. 'Atlantic'. Kinetin and/or gibberellic acid (GA$\sb3)$ at 0, 2 or 5 mg/l were tested in Murashige and Skoog (MS) medium containing 6% sucrose. GA$\sb3$ at 2 and 5 mg/l strongly inhibited stolon and tuber formation when used alone or with kinetin. Kinetin induced tuberization at all levels. Although tuberization was initiated in the absence of kinetin because of high concentration of sucrose and short photoperiod, the presence of kinetin accelerated microtuberization. The interactive effects of four cytokinin-like compounds and daylength were examined. Nodal segments were cultured on MS medium plus 6% sucrose and supplemented with either 2 mg kinetin /1, 0.1 mg thidiazuron (TDZ) /1, 1.0 mg AC 243,654 /1, 0.01 mg AC 239,604 /1, or zero-cytokinin, and under long or short days. Long days induced greater microtuberization in the cytokinin-free and AC 243,654 and AC 239,604-treated segments than those in kinetin or TDZ. Kinetin and TDZ stimulated tuberization under short days, whereas they inhibited it under long days. The role of sucrose alone and in combination with four cytokinin-like compounds on the microtuberization was investigated by using sucrose at three levels (3, 6 and 9%) and cytokinin-like compounds at five levels. Nearly all cytokinins failed to induce tuberization with 3% sucrose. Sucrose levels of 9% led to more tuber yield in the absence of cytokinin, whereas 6% sucrose was optimum for microtuber yield with cytokinins. The effects of cytokinin-like compounds on invertase activity were determined at three stages of tuberization: "hook" (stage 1), "swelling" (stage 2) and "tuber initials" (stage 3). The highest invertase activities were found at stage 1 with kinetin or TDZ treatments. While invertase activity decreased from stage 1 to 3 in all cytokinin treatments, it increased from stage 1 to 2 and then decreased for the control medium.
Subject Area
Plant propagation
Recommended Citation
Kefi, Servet, "Interactive effects of gibberellic acid, cytokinin-like compounds, sucrose and daylength on in vitro tuberization of potato (Solanum tuberosum L.) and influences of cytokinin-like compounds of invertase activity during microtuberization" (1995). ETD collection for University of Nebraska-Lincoln. AAI9611056.
https://digitalcommons.unl.edu/dissertations/AAI9611056