Pattern of Variations in Abscisic Acid Content in Suspensors, Embryos, and Integuments of Developing Phaseolus coccineus Seeds

Abstract

Free abscisic acid (ABA) content in suspensors, embryos, and integuments was determined during seed development of Phaseolus coccineus. A highly specific and sensitive solid-phase radioimmunoassay based on a monoclonal antibody raised against free (S)-ABA was used for ABA quantification. Very small amounts of ABA were detected in the suspensor during initial stages of development; later two peaks of ABA occurred. Levels of ABA in the embryo and integument show a coincident triphasic distribution: two maxima in ABA content occurred when the embryo was 11 to 12 and 15 to 16 millimeters in length; later, when the embryo was 19 to 20 millimeters long, a further increase was observed. The role of ABA in runner bean seeds is discussed in relation to the development of the different seed tissues.

Level of Abscisic Acid in Integuments, Nucellus, Endosperm, and Embryo of Peach Seeds (Prunus persica L. cv Springcrest) during Development

“…However, these differences could derive from the use of different cultivars of peach. A noticeable increase in ABA levels during the last developmental stages was also observed in Phaseolus coccineus seeds ( 12).…”

“…In fact, ABA content in the various tissues during seed development has been thoroughly measured in recent investigations carried out on Sechium edule (15) and Phaseolus coccineus (12).…”

Embryogenesis in Angiosperms: Development of the Suspensor.

“…Thus, it appears that suspensors not only are rich sources of gibberellin but also are capable of synthesizing this growth regulator at critical stages of development. A greater diversity of gibberellins has recently been identified in Phaseolus suspensors by combined gas chromatography and m a s spectrometry (Piaggesi et al, 1989). Similar compounds have also been found in the suspensors of Tropaeolum (Picciarelli et al, 1984) and Cyfisus (Picciarelli et al, 1991).…”

“…In Phaseolus, gibberellins have been shown to promote the growth in vitro of isolated embryos (Cionini et al, 1976; Yeung and Sussex, 1979), increase translational activity in the embryo proper (Brady and Walthall, 1985; Walthall and Brady, 1986), and enhance transcription in polytene suspensor cells (Forino et al, 1992). Other growth regulators, such as auxins (Przybyllok and Nagl, 1977), cytokinins (Lorenzi et al, 1978), and abscisic acid (Perata et al, 1990), have also been detected in suspensors. These studies provide further evidence that the suspensor is an important source of growth regulators, but the results are not as convincing as with gibberellins.…”

Etude histologique des embryons avortés lors des croisements entre <i>Phaseolus vulgaris</i> L. et <i>Phaseolus coccineus</i> L.

“…Elles y assurent la synthèse et l'approvisionnement de l'embryon en éléments nutritifs. Il est cependant nécessaire d'identifier et d'apprécier la nature des nutriments qui transitent par ce canal en dehors des hormones de croissance car les molécules de masse légère (les glucides) n'ont pas la même facilité de transfert que les molécules lipidiques ou protidiques (Hsu, 1979;Yeung et Clutter, 1979;Picciarelli et Alpi, 1986;Piaggesi et al, 1989;Perata et al, 1990).…”