CIRAD, UMR AGAP and Inria, Virtual Plants, 34095, Montpellier, France.
Université de Montpellier, Institut Montpelliérain Alexander Grothendieck, 34095, Montpellier, France.
New Phytol. 2017 Dec;216(4):1291-1304. doi: 10.1111/nph.14742. Epub 2017 Sep 11.
Plants exhibit dependences between shoot growth and branching that generate highly structured patterns. The characterization of the patterning mechanism is still an open issue because of the developmental processes involved with both succession of events (e.g. internode elongation, axillary shoot initiation and elongation) and complex dependences among neighbouring positions along the parent shoot. Statistical models called semi-Markov switching partitioned conditional generalized linear models were built on the basis of apple and pear tree datasets. In these models, the semi-Markov chain represents both the succession and lengths of branching zones, whereas the partitioned conditional generalized linear models represent the influence of parent shoot growth variables on axillary productions within each branching zone. Parent shoot growth variables were shown to influence specific developmental events. On this basis, the growth and branching patterns of two apple tree (Malus domestica) cultivars, as well as of pear trees (Pyrus spinosa) between two successive growing cycles, were compared. The proposed integrative statistical models were able to decipher the roles of successive developmental events in the growth and branching patterning mechanisms. These models could incorporate other parent shoot explanatory variables, such as the local curvature or the maximum growth rate of the leaf.
植物表现出与分枝相关的生长依赖性，从而产生高度结构化的模式。由于涉及到事件的顺序（例如节间伸长、腋芽的发生和伸长）以及亲本枝条上相邻位置之间的复杂依赖性，因此，模式形成机制的特征描述仍然是一个悬而未决的问题。基于苹果和梨树数据集，构建了称为半马尔可夫切换分区条件广义线性模型的统计模型。在这些模型中，半马尔可夫链既代表了分枝区的顺序和长度，也代表了亲本枝条生长变量对每个分枝区内腋芽发生的影响。结果表明，亲本枝条生长变量会影响特定的发育事件。在此基础上，比较了两个苹果品种（Malus domestica）以及两个连续生长周期之间的梨（Pyrus spinosa）的枝条生长和分枝模式。所提出的综合统计模型能够解析连续发育事件在生长和分枝模式形成机制中的作用。这些模型可以包含其他亲本枝条解释变量，例如局部曲率或叶片的最大生长速率。
