The Influence of Shoot Growth on the Pattern of Axillary Development on the Long Shoots of Young Apple Trees (Malus domestica Borkh.)

Corner's rules as a framework for plant morphology, architecture and functioning – issues and steps forward

“…This is supported by findings on branch plagiotropy in Araucaria and Coffea likely resulting from an early SAM signal (see discussion in Chomicki et al ., ). However, results obtained on individual metamers of peach (Kervella et al ., ) and apple (Lauri & Térouanne, ) show that the growth dynamics of the leaf or of both the internode and the leaf, respectively, affect the axillary bud fate (namely, latent, vegetative, floral; Lauri & Normand, ). The challenge is now to better investigate when and how the phenotypic correlation space is built during plant development and growth and in particular to analyze whether organ size and shape, and axillary production size and fate, are fully pre‐determined in the SAM or depend on interactions among growing or mature organs at later stages.…”

Are the effects of winter temperatures on spring budburst mediated by the bud water status or related to a whole-shoot effect? Insights in the apple tree

“…A first explanation could be that the bud water status would evolve only a few days prior to budburst which depends not only on the plant material but also on the climatic conditions during this period leading to the quasi-impossibility to determine precisely, in our experiment, when to sample. However, our results strongly suggested that the growing potential of the bud depends both on an endogenous growing ability Table 1 Hydraulic conductance (K stem-bud ; mmol MPa -1 s -1 ), water potential (WP; MPa) and relative water content (RWC; %) before budburst (mid-March 2012), and proleptic lateral growth (PLG; %) on one-year-old wood (July 2012) in the distal third of parent shoots of four apple cultivars grown under contrasted winter temperature treatments, cold winter and mild winter, with 1,428 and 99 h below 7.2°C, respectively (Lauri and Térouanne 1998) in relation to the number of appendages in the bud positively related to K stem-bud (Lauri et al 2008) and on a whole-shoot effect. This latter effect is likely related to highly dynamic competitions among buds before budburst through a temporal (e.g., the first bud to burst has a higher growth potential, also called primigenic dominance) and/or a positional effect along the stem (Maguylo et al 2012), and between buds and the parent shoot (Champagnat 1983).…”

“…However, interactions between the bud endogenous potential and the parent stem are still not fully understood, and large buds with functional vascular connections may be fully dormant (Brewer et al 2009). It has been shown that branching on the one-yearold shoot is usually composed of consecutive zones each one characterized by a homogeneous composition of laterals of different types (Lauri and Térouanne 1998;Napoli et al 1999). The genetic variability of these branching patterns has been shown in the apple (Costes and Guédon 2002).…”

A Comparative Study on the Branching Pattern of Monocyclic and Bicyclic Shoots of Apple cv. “Fuji”

“…Although shoot growth and branching patterns have been studied for many species, including fruit trees ( Costes and Guédon, 2002 ; Renton et al, 2006 ; Negrón et al, 2013 ; Prats-Llinàs et al, 2019 ), their relationship is still not fully understood. Many studies have shown that the development of different types of lateral buds is related to their within-shoot location ( Lauri and Terouanne, 1998 ; Guédon et al, 2001 ; Costes and Guédon, 2002 ). In trees, usually the most distal lateral buds develop into long shoots, with a decrease in length from the top of the bearing shoots, a phenomenon known as acrotonic gradient ( Cook et al, 1998 ).…”

“…In trees, usually the most distal lateral buds develop into long shoots, with a decrease in length from the top of the bearing shoots, a phenomenon known as acrotonic gradient ( Cook et al, 1998 ). In apple trees ( Malus x domestica ), floral buds are located below the acrotonic zones ( Crabbé, 1984 ; Lauri and Terouanne, 1998 ). The floral bud develops into a short swollen axis, called bourse, with rosette leaves at the basal part and an inflorescence at the terminal part ( Pratt, 1988 ), and, therefore, corresponds to a mixed inflorescence.…”