A study by cryo‐scanning electron microscopy of the initiation and early development of an inflorescence in glasshouse celery (Apium graveolens L. var. dulce (Miller) Pers.) grown under inductive conditions

Abstract

Summary The morphology of flower initiation and early development in glasshouse celery (Apium graveolens L. var. dulce (Miller) Pers.) cv. Celebrity was studied by means of apical dissections and cryo‐scanning electron microscopy. Easily recognisable morphological features were used to define seven stages in the early development of the inflorescence. A highly significant linear regression was established between the logarithm of the apical diameter (measured diametrically across the apical dome between the two most recently initiated leaf or inflorescence primordia) and these discrete floral stages. There was no strong evidence that either the origin or the slope of the regression varied with different combinations of temperature (viz. 10°C or 14°C) and daylength (viz. natural, short or long) which were conducive for the initiation and development of an inflorescence. It is suggested that both apical diameter and floral stage may be used as parameters for assessing the influence of environmental factors such as temperature and daylength on the floral development of glasshouse celery.

A morphological study of flower initiation and development in strawberry (Fragaria x ananassa) using cryo‐scanning electron microscopy

“…This pattern of initial morphological change to the apical dome agrees with previous studies on strawberry (Guttridge, 1952;Jahn & Dana, 1970), as well as other species, e.g. celery (Roelofse, Atkey, Hand & Hall, 1994). Fig.…”

Early Field Detection of Bolting in Celery

“…In 2000, the main stem apex was dissected under a binocular microscope (magnification 40×) to determine the stage of early development of infl orescence, according to the scale previously defi ned by Roelofse et al (1989). The discrete developmental stages of celery infl orescence ranged from 0 (no evidence of infl orescence development) to 7 (complete transition from a vegetative meristem to an infl orescence) (Roelofse et al, 1989(Roelofse et al, , 1994. We considered stage 1 (initiation of infl orescence) of the main stem apex to be the microscopic criterion for celery fl oral induction.…”

“…As a result, the period between perception and the point when the stem is too long is critical for management decisions about time to harvest. The objective of this study was to determine whether celery infl orescence initiation observed either visually (Pressman and Sachs, 1985) or microscopically (Roelofse et al, 1989(Roelofse et al, , 1994) could be combined with growth data to determine the optimal time to harvest.…”