Branch development in custard apple (cherimoya Annona cherimola Miller × sugar apple A. squamosa L.) in relation to tip-pruning and flowering, including effects on production

Abstract

Custard apple has cryptic axillary buds, hidden from view by the base of the petiole. This has led to confusion about custard apple's flowering habit. Flowering only occurs during early branch development, and can be forced at any time of the growing season simply by removing leaves. Here, we show that flowering is terminal, not extra-axillary, and that the apparent continuation of the main stem beyond the flower is, instead, a sympodial branch. Secondary (including sympodial) branching only occurs during early branch development. Thereafter, axillary bud release is inhibited by the subtending leaf. Here, we show that summer tip-pruning of all branches arrests canopy development until the following spring owing to this inhibition. Although summer tip-pruning prevented new vegetative growth in the canopy, fruit size decreased relative to the control trees by ca. 23%. The reason for this decrease was probably related to increased carbon limitation to growth given that dawn water soluble and total nonstructural carbohydrate concentrations were lower in the tip-pruned trees. Thus, it appears that the reduced competition between fruit development and new vegetative growth in the tip-pruned trees was more than matched by lower photosynthetic capacity in the arrested canopy. Trees grown inside a shade-house were more vigorous than those grown outside. The difference in vigour had little effect on fruit size.

Transcriptome Analysis and Identification of Genes Associated with Floral Transition and Flower Development in Sugar Apple (Annona squamosa L.)

“…The axillary buds of sugar apple are cryptic, obscured by the base of the petiole, and released following leaf abscission. Summer defoliation promotes flowering by releasing dormant subpetiolar axillary buds and causes the resumption of flower development (Olesen and Muldoon, 2009). The flowers are born terminally on the new shoots.…”

Role of Cytokinin, Strigolactone, and Auxin Export on Outgrowth of Axillary Buds in Apple

“…The different stages in axillary bud development are generally existed, but there are no clear separated points among stages (Shimizu-Sato and Mori, 2001; Barbier et al, 2015). The axillary buds of apple, located in the leaf axil, are generally dormant due to the correlative inhibition exerted by apical buds (Cline, 1997; Olesen and Muldoon, 2009). Outgrowth of axillary buds (branching) in apple typically occurs during spring budburst following winter dormancy (Cook et al, 2001).…”

Crescimento, produção e qualidade de frutos de atemoieira ‘Gefner’ submetida a diferentes intensidades de poda

“…X pinha Annona squamosa L.) é uma planta semi-decídua de origem subtropical que, em geral, perde suas folhas progressivamente na primavera (OLESEN & MULDOON, 2009). O I Universidade Estadual de Montes Claros (UNIMONTES), Rua Reinaldo Viana, 2630, 39440-000, Janaúba, MG, Brasil.…”

“…II Departamento de Fitotecnia, Universidade Federal de Viçosa (UFV), Viçosa, MG, Brasil. alongamento dos brotos vegetativos é contínuo, iniciando-se na primavera até o próximo inverno. Em geral, o desenvolvimento dos ramos é linear e até o fi nal da estação podem atingir comprimento de 3m ou mais (OLESEN & MULDOON, 2009). O fl orescimento ocorre restritamente no estádio inicial de desenvolvimento dos brotos e opostos às folhas (GEORGE & NISSEN, 1991).…”