Christianson M L, Warnick D A
Dev Biol. 1983 Feb;95(2):288-93. doi: 10.1016/0012-1606(83)90029-5.
Leaf explants of Convolvulus arvensis produce shoots when cultured on Murashige and Skoog salts, sucrose, vitamins and 0.05 mg/liter IAA plus 7.0 mg/liter 2-isopentenyl adenine. Shoot-inducing, root-inducing, or callus-inducing medium (SIM, RIM, or CIM) will cause small amounts of callus to form at the cut edges of the explant. This first-formed callus is developmentally interchangeable: SIM induces shoots in callus formed on CIM or SIM with equal effect and efficiency. Once induction begins in competent callus, the callus is no longer interchangeable. Under the continued influence of SIM, cells, or groups of cells become determined for shoot formation. This determination is strongly canalized for shoot formation: subsequent transfer to root-inducing medium does not affect the formation of shoots by the explant. The control of organogenesis by the auxin/cytokinin balance must occur between the time the tissue becomes competent and the time it is determined for shoot (or root) development. It is not known whether this control is a single or multiple phenomenon.
田旋花的叶片外植体在添加了Murashige和Skoog盐类、蔗糖、维生素以及0.05毫克/升吲哚乙酸（IAA）和7.0毫克/升2-异戊烯基腺嘌呤的培养基上培养时会产生芽。芽诱导培养基、根诱导培养基或愈伤组织诱导培养基（SIM、RIM或CIM）会使外植体的切口边缘形成少量愈伤组织。这种最初形成的愈伤组织在发育上是可互换的：SIM在CIM或SIM上形成的愈伤组织中诱导芽的效果和效率相同。一旦在有能力的愈伤组织中开始诱导，愈伤组织就不再可互换。在SIM的持续影响下，细胞或细胞群开始确定形成芽。这种确定对于芽的形成具有很强的定向性：随后转移到根诱导培养基中不会影响外植体形成芽。生长素/细胞分裂素平衡对器官发生的控制必定发生在组织具备能力到确定进行芽（或根）发育的这段时间内。目前尚不清楚这种控制是单一现象还是多种现象。
