Nucellar Embryony and Juvenile Characters in Clonal Varieties of Citrus*

Plant Architecture: A Dynamic, Multilevel and Comprehensive Approach to Plant Form, Structure and Ontogeny

“…The transition between these phases is currently referred to as phase change (Jones, 1999). In addition to reproductive function, ontogenetic changes in several other parameters and morphological, anatomical and/or functional features has long been described in plants (Koch, 1873;Carrière, 1880;Hochtetter, 1880;Beissner, 1888;Cockayne, 1912;Frost, 1938;Webber and Batchelor, 1948;Ashby, 1949;Doorenbos, 1954;Schaffalitzky de Muckadell, 1954Brink, 1962;Trippi, 1963;Wardle, 1963;Greenwood and Atkinson, 1977;Poethig, 1990Poethig, , 2003Jones, 1999;Kaplan, 2001) and these changes may be simultaneous with the appearance of reproductive capacity during development. At the whole individual level, plant development may thus be viewed as a succession of phases, each characterized by a set of several features or parameters.…”

Juvenile Stages in Woody Plants

“…Tbey (jnote Frost (194.' }) wben saying: the trunk of a tborny seedling and the proximal portion of Its main branches retain for a long time tbe ability to i)roduce tborny sboots.s When studying tlie tborny juvenile phase in Citrus, Frost (1938) even showed Ihat grafts from the thorny lower part of one unbranched shoot became thorny, wbereas grafts from the smooth distal part oi the same shoot became smooth. 'I'bis proves that stability in respect of the jjbase of development witbin tbe same shoot generation, even in tbe same sboot, was so great that transference by vegetative propagation was possible.…”

Diversity among nucellar-seedling lines of Satsuma mandarin and differences from the parental old line

“…Nucellar origin of citrus seedlings is ordinarily indicated by close resemblance to the seed parent and, after cross pollination, by absence of pollen-parent characters. Almost invariably, gametic seedlings, even from selfing, are readily distinguished from nucellar ones by fruit characters (Frost, 1926(Frost, , 1952. With our Satsumas, the only possibly questionable type is strain C, which is rather unlike the seed parent.…”

“…Evidence of the general behavior of several nucellar lines has been recently reported (Batchelor and Cameron, 1949;Frost, 1952;Cameron and Soost, 1952). Older evidence has been presented and hypotheses discussed by Hodgson and Cameron (1938) and Frost (1938;pp. 818-832 in Webber and Batchelor, 1943).…”