The Physiology of Growth in Apple Fruits I. Cell Size, Cell Number, and Fruit Development

Abstract

SummaryThe problem of fruit size in the Australian apple variety Granny Smith was examined in relation to mean cell size and mean cell number. Cell size gradients in the fruit and changes in cell shape and packing during development were noted.Observations of workers on other varieties that cell division ceased within four weeks of pollination were confirmed. Variation in size of fruits at maturity was shown to be due mostly to variation in cell number and only to a small extent to mean cell size. Cell enlargement was shown to continue throughout the life of the fruits on the tree.

Quantitative Analysis of Cell Organization in the External Region of the Olive Fruit

“…In contrast, other authors have used the strictly epidermal definition of the exocarp on the basis of either histological observations (King 1938;Bain and Robertson 1951) or a histogenic approach that treats the exocarp as the part of the fruit derived from the outer epidermis of the pollinated carpel (Bobrov et al 2005). In this case, the subepidermal layers are interpreted as being a part of the outer mesocarp or as a transitionary zone (King 1938;Bain and Robertson 1951;Roth 1977;Bobrov et al 2005). Similarly, even when the exocarp is considered to be multiseriate, different interpretations of the number of participating subepidermal layers can be made.…”

“…Multiseriate exocarp definitions are usually based on the interpretation of a morphologically distinct subepidermal tissue, sometimes called a hypodermis, that differs from the mesocarp in cell size (either larger or smaller), metabolism, and/or form (shape, cell wall characteristics; Sterling 1953;Considine and Knox 1981;Lavee 1986;Archibald and Melton 1987;King et al 1987;Yamaguchi et al 2003;Mintz-Oron et al 2008). In contrast, other authors have used the strictly epidermal definition of the exocarp on the basis of either histological observations (King 1938;Bain and Robertson 1951) or a histogenic approach that treats the exocarp as the part of the fruit derived from the outer epidermis of the pollinated carpel (Bobrov et al 2005). In this case, the subepidermal layers are interpreted as being a part of the outer mesocarp or as a transitionary zone (King 1938;Bain and Robertson 1951;Roth 1977;Bobrov et al 2005).…”

The Development of Bean Seeds (Phaseolus vulgaris L.).

“…Few cell divisions occurred in cotyledons older than three weeks after flowering; at this time the dry weight of the bean seeds was less than 1/6 of that finally reached. In apples (1,20), cucurbits (27, 28), and tomatoes (12) cell division also ceases long before the growth of the fruit stops.…”

“…It is unfortunate that so few cellular studies have been made, since they might indicate cell similarities that are not apparent at the organ level. The physiological investigations on the growth of plant cells that came to the author's attention include cowpea roots (22), corn roots (8, 11), onion roots (31), pea roots (2, 4), and apple fruit pulp (1,20,23); these papers are considered in the discussion of the results.The aim of this investigation was to describe the development of bean seeds in cellular terms and to compare the per cell values obtained with those of other plant cells. To this end, the fresh weight, dry weight, nitrogen (N) content, phosphorus (P) content, and the rate of oxygen uptake were measured and cell counts were made on maturing bean seeds.…”

“…It is unfortunate that so few cellular studies have been made, since they might indicate cell similarities that are not apparent at the organ level. The physiological investigations on the growth of plant cells that came to the author's attention include cowpea roots (22), corn roots (8, 11), onion roots (31), pea roots (2, 4), and apple fruit pulp (1,20,23); these papers are considered in the discussion of the results.…”