Phytohormones effects

A representative of this type of compounds, 6,7-dihydro-57/-pyrrolo[l,2-a]purine-9-amine (3), was accessible by heating 5-amino-imidazole-4-carbonitrile (1) with 5-ethoxy-3,4-dihydro-2//-pyrrole (2) (88JCS(P 1)593). Compound 3 shows a phytohormone effect greater than that of benzyladenine (89JAP(K)1) (Scheme 1). 

Barlow PW, Macdonald PDM (1973) An analysis of the mitotic cell cycle in the root meristem of Zea mays. Proc Roy Soc Lond B 183 385-398 Basrur SV, Fletcher RA, Basrur PK (1976) In vitro effects of 2,4-dichlorophenoxy acetic acid (2,4-D) on bovine cells. Can J Comp Med 40 408-415 Batra MW, Edwards KL, Scott TK (1975) Auxin transport in roots Its characteristics and relationships to growth. In Torrey JG, Clarkson DT (eds) The development and function of roots. Academic Press, London New York, pp 299-325 Beasley CA, Ting IP (1973) The effects of plant growth substances on in vitro fiber development from fertilized cotton ovules. Am J Bot 60 130-139 Beasley CA, Ting IP (1974) Phytohormone effects on in vitro cotton seed development. 

Although plant cell culture is not as cost effective as plant cultivation in the open field, it will become an economical process if higher protein yields can be achieved [58]. The cultivation medium of plants is chemically defined, consisting of a carbon source, minerals, vitamins and phytohormones [69]. Furthermore, it is protein-free and relatively inexpensive. In contrast, animal cells often require complex supplements such as fetal calf serum and/or expensive growth factors, although serum-free cultivation is possible in case of Chinese hamster ovary (CHO) cells [70]. 

Thus, the presence of a silatrane group in the phytohormone molecule prolongs its effect or facilitates the auxin transport through the biomembranes. 

However, the evidence that phenolic acids and polyphenols cause their effect through action on phytohormones is not the complete picture. 

The addition of a single phytohormone or their combination to the hairy root cultures transformed with A. rhizogenes A4 reduced the alkaloid formation substantially (Fig. 8b). The inhibitory effect of phytohormones on alkaloid production was larger when these hairy roots were cultured in the light. 

Table 2. Effects of phytohormones and basal media on shoot multiplication of C. ipecacuanha after 8 weeks of culturing at 25 °C under 16 hr/day light (80 pEm S" )...

Effects of phytohormones on alkaloid production in ipecac roots cultured on MS solid media... 

An interesting effect of Aceria attack on the abscisic acid and ethylene content in the fruits was recorded. This stressor increased the highest values of stimulating phytohormones also. These substances can disturb the dormancy and cause the highest germinability (Fiserova et al., 1999). 

The biological activity of fusicoccin A appears to be associated with its effect on the plasma membrane, where it binds to a protein and interacts with the H" -ATPase. The binding to the protein leads to an opening of the stomata, a consequent high loss of water and the wilting of the leaves. The interaction of the fusicoccins and coylenins with the plasma H" -ATPase can also lead to some phytohormone-like effects. 

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