Exploring within-tree architectural development of two apple tree cultivars over 6 years.

The present study addresses the prediction of apple tree development, taking into account both the number and within-tree position of tree components. The architectural development of two trees per scion cultivar, 'Fuji' and 'Braeburn', was studied by describing all shoots over 6 years. Flowering and fruiting were observed over 3 years. The description included different scales [entire trees, axes, growth units (GUs) and metamers], and the analysis compared all axes of the trees as a function of their branching order and age. Three main aspects of vegetative development were investigated: the quantity of primary growth; the number and nature of developing axillary shoots; and meristem death. Results confirm the existence of within-tree morphological gradients, and show that the decrease in growth was comparable in magnitude for all axes and GUs, irrespective of their position. This decrease results from a reduction in the number of metamers per GU, which was modelled by an exponential function. The decrease in growth involved changes in the number and nature of the axillary shoots, which could be described by simple functions. The probability of spur death was constant over the years but differed according to cultivar and type of bearing shoot. The within-tree probability of flowering and fruiting was predictable for 'Braeburn' because axes, regardless of their position and type, had a high probability of flowering and a low probability of fruit set which led to a regular bearing habit. In contrast, 'Fuji' had an alternating bearing behaviour that was more complex to predict. This appeared to result from a synchronized increase in the probability that all GUs at tree scale are floral, combined with a high probability of fruit set. The consequences of these results for both yield prediction and architectural simulations are discussed.

[1]  Brendan Lane,et al.  The use of positional information in the modeling of plants , 2001, SIGGRAPH.

[2]  James White,et al.  THE PLANT AS A METAPOPULATION , 1979 .

[3]  C. Atkinson,et al.  Wood and tree age as factors influencing the ability of apple flowers to set fruit , 1994 .

[4]  Y Guédon,et al.  Modelling branching patterns on 1-year-old trunks of six apple cultivars. , 2002, Annals of botany.

[5]  Philippe De Reffye,et al.  Growth units construction in trees: A stochastic approach , 1991 .

[6]  Christophe Godin,et al.  Exploring plant topological structure with the AMAPmod software: an outline. , 1997 .

[7]  E. W. Hewett,et al.  Wood age and leaf area influence fruit size and mineral composition of apple fruit , 1994 .

[8]  C. Huyghe,et al.  Analysis of Grain-Yield Components and Inflorescence Levels in Winter-Type White Lupin , 2000 .

[9]  C. V. Cutting,et al.  The Physiology of Tree Crops. , 1970 .

[10]  H. Jonkers Biennial bearing in apple and pear: A literature survey , 1979 .

[11]  H. Sinoquet,et al.  Assessment of the three-dimensional architecture of walnut trees using digitising , 1997 .

[12]  Bud Structure in Relation to Shoot Morphology and Position on the Vegetative Annual Shoots of Juglans regia L. (Juglandaceae) , 2001 .

[13]  Evelyne Costes,et al.  Quantitative analysis of shoot development and branching patterns in Actinidia. , 2002, Annals of botany.

[14]  Yves Caraglio,et al.  Architecture, gradients morphogénétiques et âge physiologique chez les végétaux , 1997 .

[15]  Y. Guédon,et al.  Pattern analysis in branching and axillary flowering sequences. , 2001, Journal of theoretical biology.

[16]  Harri Hakula,et al.  Components of functional-structural tree models , 2000 .

[17]  J. R. Porter A MODULAR APPROACH TO ANALYSIS OF PLANT GROWTH , 1983 .

[18]  Christophe Godin,et al.  A Method for Describing Plant Architecture which Integrates Topology and Geometry , 1999 .

[19]  P. D. Reffye,et al.  Modélisation et simulation de l'architecture des végétaux , 1997 .

[20]  Pierre-Eric Lauri,et al.  Shoot type demography and dry matter partitioning: a morphometric approach in apple (Malus ×domestica) , 2001 .

[21]  J. W. Palmer,et al.  Effects of Shade on the Growth and Cropping of Apple Trees. I. Experimental Détails and Effects on Vegetative Growth , 1977 .

[22]  Godin,et al.  A multiscale model of plant topological structures , 1998, Journal of theoretical biology.

[23]  D. Ferree,et al.  Chemical thinning 'Fuji' apple in the midwest. , 2000 .

[24]  R. Meilan Floral induction in woody angiosperms , 1997, New Forests.

[25]  Philippe De Reffye,et al.  Stochastic modelling of apricot growth units and branching. , 1992 .

[26]  Christophe Godin,et al.  Measuring and analysing plants with the AMAPmod software , 1997 .

[27]  O. Smirnova,et al.  Age states of plants of various growth forms: a review. , 1980 .

[28]  André Lacointe,et al.  Carbon allocation among tree organs: A review of basic processes and representation in functional-structural tree models , 2000 .

[29]  E. Costes,et al.  3D digitizing based on tree topology: application to study the variability of apple quality within the canopy , 1999 .

[30]  Laurent Gauthier,et al.  GPSF: a generic and object-oriented framework for crop simulation , 1999 .

[31]  Terence L. Robinson,et al.  The Bases of Productivity in Apple Production Systems: The Role of Light Interception by Different Shoot Types , 1996 .

[32]  Pierre-Eric Lauri,et al.  Relationship between the early development of apple fruiting branches and the regularity of bearing—An approach to the strategies of various cultivars , 1997 .

[33]  Christophe Godin,et al.  A distance measure between plant architectures , 2000 .

[34]  J. Fisher,et al.  How Predictive are Computer Simulations of Tree Architecture? , 1992, International Journal of Plant Sciences.

[35]  I. J. Warrington,et al.  Influence of Orientation and Position of Fruiting Laterals on Canopy Light Penetration, Yield, and Fruit Quality of ‘Granny Smith’ Apple , 1988, Journal of the American Society for Horticultural Science.

[36]  Evelyne Costes,et al.  A COMPARISON OF DIFFERENT FRUITING SHOOTS OF PEACH TREE , 1998 .

[37]  Przemyslaw Prusinkiewicz,et al.  The Algorithmic Beauty of Plants , 1990, The Virtual Laboratory.

[38]  Terence L. Robinson,et al.  Bases of Yield and Production Efficiency in Apple Orchard Systems , 1991 .

[39]  D. L. Abbott The Apple Tree: Physiology and Management , 1984 .