Am J Bot. 1997 Jul;84(7):873.
The response of axillary buds to floral stimulus activity in stem pieces was examined in two near-isogenic cultivars of tobacco that differ in the recessive maryland mammoth (mm) allele, which confers short-day behavior. All axillary buds from day-neutral plants assayed on six-internode stem pieces made few nodes (less than 20) before flowering, while axillary buds from plants homozygous for mm assayed on six-internode stem pieces either did not flower in noninductive conditions or made many nodes before flowering in inductive conditions. About 80% of day-neutral axillary buds grafted onto day-neutral stem pieces did not respond to floral stimulus in stem pieces, indicating that the floral stimulus in stem pieces is ephemeral. In other graft combinations, the proportion of axillary buds that did respond to floral stimulus in stem pieces was substantially reduced from the 20% of day-neutral buds on day-neutral stem pieces that responded. These results indicate that the mm allele probably reduces both the amount of floral stimulus activity in stem pieces and the competence of axillary buds to respond.
我们检测了两个近等基因烟草品种腋芽对茎段中花刺激活性的反应，这两个品种在隐性马里兰巨型（mm）等位基因上存在差异，该基因赋予短日行为。在六节间茎段上测定的来自非日中性植物的所有腋芽在开花前形成的节数很少（少于 20 个），而在六节间茎段上测定的 mm 纯合植株的腋芽要么在非诱导条件下不开花，要么在诱导条件下开花前形成许多节。大约 80%的非日中性腋芽嫁接到非日中性茎段上，对茎段中的花刺激没有反应，这表明茎段中的花刺激是短暂的。在其他嫁接组合中，对茎段中花刺激有反应的腋芽比例从非日中性茎段上 20%的非日中性芽中显著降低。这些结果表明，mm 等位基因可能降低了茎段中花刺激活性的数量和腋芽对其的反应能力。
