Gordon D, Damiano C, DeJong T M
Department of Plant Sciences, Mail Stop 2, University of California at Davis, One Shields Avenue, Davis, CA 95616-8780, USA.
Tree Physiol. 2006 Apr;26(4):537-44. doi: 10.1093/treephys/26.4.537.
We investigated the influence of bud position, cultivar, tree age, tree carbohydrate status, sampling date, drought and light exposure on the number of leaf primordia formed in dormant vegetative peach buds (Prunus persica (L.) Batsch) relative to the number of primordia formed after bud break (neoformed). During winter dormancy, vegetative peach buds from California and Italy were dissected and the number of leaf primordia recorded. Between leaf drop and bud break, the number of leaf primordia doubled from about five to about 10. Parent shoot length, number of nodes on the parent shoot, cross-sectional area of the parent shoot, bud position along the parent shoot and bud cross-sectional area were correlated with the number of leaf primordia. Previous season light exposure, drought and tree carbohydrate status did not affect the number of leaf primordia present. The number of leaf primordia differed significantly among peach varieties and tree ages at leaf drop, but not at bud break. Our results indicate that neoformation accounted for all shoot growth beyond about 10 nodes. The predominance of neoformed shoot growth in peach allows this species great plasticity in its response to current-season conditions.
我们研究了芽位、品种、树龄、树体碳水化合物状况、采样日期、干旱和光照对休眠营养桃芽（Prunus persica (L.) Batsch）中形成的叶原基数的影响，该叶原基数相对于芽萌发后形成的原基数（新形成的）。在冬季休眠期间，解剖了来自加利福尼亚州和意大利的营养桃芽，并记录了叶原基的数量。在落叶至芽萌发期间，叶原基的数量从约5个增加一倍至约10个。母枝长度、母枝上的节数、母枝的横截面积、沿母枝的芽位以及芽的横截面积与叶原基数量相关。上一季的光照、干旱和树体碳水化合物状况并未影响当时存在的叶原基数量。在落叶时，不同桃品种和树龄的叶原基数量存在显著差异，但在芽萌发时则无差异。我们的结果表明，新形成的芽生长占了超过约10个节的所有新梢生长。桃中新形成的新梢生长占优势，这使得该物种对当季条件的反应具有很大的可塑性。
