Endogenous plant hormones

The generally recognised families of endogenous plant hormones comprise ... 

By the criteria listed, the evidence is consistent with brassinosteroids being a new family of endogenous plant hormones. However, when Jacobs rules (61) for determining the involvement of a hormone in a process (Presence, Excision, Substitution, Isolation, Generality, Specificity), are considered -... 

It has been demonstrated that the physiological function of BR is mediated through endogenous plant hormones (5). It has been also suggested that plant hormones were related to the photomorphogenic events caused by phytochrome (13). 

Acknowledgment. We wish to thank Dr. S. Watanabe, Institute of Agrobiological Resourses, for helpful discussions about the endogenous plant hormone analyses. 

Although quantitative analysis of endogenous plant hormones by traditional GC has serious limitations, isotopic dilution analysis by GC-SIM using a single internal standard labelled with a stable isotope, such as H, C or N, is a completely different proposition [3-6]. Because the cost of a simple, computer-controlled, quadrupole-mass spectrometer has fallen substantially, and many highly enriched, isotopically-labelled compounds suitable for use as internal standards in quantitative analysis, can be either synthesized (1) or purchased from commercial sources (see Table 1), capillary GC-SIM is now the quantitative assay of choice in the vast majority of laboratories in which endogenous plant hormones are analysed on a routine basis. 

As a first step in quantitative analysis of endogenous plant hormones, for each compound under-study, an isotopically-labelled analogue should be added as an internal standard to every extract that is processed, so the losses that invariably occur during purification can be properly assessed (Section 3). At the analytical stage, it is imperative for investigators to provide evidence to support the accuracy of the quantitative estimates that are obtained. As explained in Section 6.1, with GC-SIM this can be achieved routinely, with every sample that is analysed, simply by scrutinizing the m/z peak area ratios. 

Endogenous Plant Hormones in Rice in Relation to the Regulation of Its Life Cycle... 

It is very important to clarify the roles of endogenous plant hormones in the regulation of the life cycle of higher plants from the standpoint of not only plant physiology but agricultural application as well. 

Roles of Endogenous Plant Hormones in the Regulation of the Life Cycle of Rice... 

The loss of essential materials (metabolite, enzymes and hormones, etc.) from the seeds most probably is one of the chief causes of soaking in ury. In Imbibition of pea, growth hormones placed in solution under aeration during germination may partly replenish endogenous plant hormones lost in the soaking solution (Choe, 1972). 

Dathe W, Ronsch H, Preiss A, Schade W, Sembdner G, Schreiber K. Endogenous plant hormones of the broad bean, Vida faba L. (-)-jasmonic acid, a plant growth inhibitor in pericarp. Planta 1981 153 530-535. 

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