Free indole-3-acetic acid levels were measured by gas chromatography-mass spectrometry in three ultra-tall 'slender' Pisum sativum L. lines differing in gibberellin content. Measurements were made for apices and stem elongation zones of light-grown plants and values were compared with wild-type, dwarf, and nana phenotypes in which internode length is genetically regulated, purportedly via the g...

The research was conducted to evaluate Eleusine indica (L.) Gaertn. (goosegrass) phenotypic diversity in biotypes collected from managed turfgrass, noncrop, and row crop environments. A common-garden experiment quantify morphological characteristics. Biotypes were primarily distinguished along a single principal component that separated taller growing types with lower tiller numbers, larger lea...

Whereas gibberellin and ethylene may both hasten abscission development in explant tissues (6, 7), and may provoke simi,lar actions in releasing some dormant buds or seeds (11, 17) in several growth functions these 2 regulators may have opposing types of effects. For example, ethylene and gibberellin (GA) ihave opposite effects in senescence development (3, 13). The reports that gibberellin can...

The Arabidopsis basic helix-loop-helix (bHLH) proteins INDEHISCENT (IND) and ALCATRAZ (ALC) specify tissues required for fruit opening that have major roles in seed dispersal and plant domestication. Here, we show that synthesis of the phytohormone gibberellin is a direct and necessary target of IND, and that ALC interacts directly with DELLA repressors, which antagonize ALC function but are de...

Although phytohormones such as gibberellins are essential for many conserved aspects of plant physiology and development, plants vary greatly in their responses to these regulatory compounds. Here, we use genetic perturbation of endogenous gibberellin levels to probe the extent of intraspecific variation in gibberellin responses in natural accessions of Arabidopsis (Arabidopsis thaliana). We fi...

Gladiolus is an important marketable cut flower, especially valued for use in floral arrangements. We assessed the effects of two different methods of application (foliar spray and drench) and various concentrations of gibberellic acid (GA3), salicylic acid (SA), mival (MI) and krizatcin (KR) on vegetative and reproductive features of Gladiolus hybridus. The experiment was planned in a factoria...

Strigolactone (SL), auxin and cytokinin (CK) interact to regulate shoot branching. CK has long been considered to be the only key phytohormone to promote lateral bud outgrowth. Here we report that gibberellin also acts as a positive regulator in the control of shoot branching in the woody plant Jatropha curcas. We show that gibberellin and CK synergistically promote lateral bud outgrowth, and t...

Gibberellin influences the rest period or dormancy of seeds (4), shoots (1), and other plant parts (2, 5, 9). In potato, Solanum tuberosum, a condition of physiological rest prevails from the time of tuber initiation until 6 to 12 weeks after harvest depending on varietal characteristics (3). The rest period has been markedly curtailed by immersing freshly harvested potato tubers in gibberellin...

Research on the classical plant hormones continues to uncover fascinating interactions between these crucial regulatory compounds.Recent papers describe ‘crosstalk’ between the abscisic acid and ethylene signaling pathways in Arabidopsis, and how the nature of this interaction depends on organ type.Auxin has now been shown to promote the biosynthesis of active gibberellin in pea,by up-regulatin...

Two-dimensional gel electrophoresis was used to characterize the molecular mechanism of gibberellin-induced stem elongation in maize and pea. Dwarf mutants of maize (d-5) and pea (Progress No. 9) lack endogenous gibberellin (GA(1)) but become phenotypically normal with exogenous applications of this hormone. Sections from either etiolated maize or green pea seedlings were incubated in the prese...