Shunpei Uemoto

Micropropagation of a terrestrial Cymbidium species using rhizomes developed from seeds and pseudobulbs

Growth of Cymbidium kanran rhizome was enhanced by higher NAA:BAP ratios in modified Murashige & Skoog (MS) media. Only vegetative shoots resulted from rhizomes cultured in vitro when lower NAA:BAP ratios were used. The rhizomes were induced from the axils of leaves when shoots were explanted to medium containing higher concentrations of NAA. Root formation of C. kanran was inhibited by the addition of either auxin or cytokinin to the culture media. Differentiation of the rhizomes into plantlets occurred when the concentrations of ammonium nitrate and potassium nitrate in MS medium wewe reduced. The modified MS medium containing lesser amounts of potassium nitrate and ammonium nitrate than those of the original MS media, and was optimal for the production of plantlets from rhizomes of C. kanran without addition of auxin and cytokinin.

Rhizome induction and plantlet regeneration of Cymbidium goeringii from flower bud cultures in vitro

Apical flower buds of Cymbidium goeringli Reichenbach fil. (ca 2 mm long) exeised from infloreseences (ca 5 cm long) were explanted on modified Murashige & Skoog medium (=MS medium) supplemented with N6-benzyladenine (BA) and α-naphthaleneacetic acid (NAA). Within 107 days of culture, swelling growth, chlorophyll synthesis, and subsequent rhizome differentiation were observed. MS medium containing 0.1 mg l-1 BA and 10 mg l-1 NAA was found to be optimal for initiating rhizome development and subsequent plantlet regeneration.Explants cultured on MS medium supplemented with 1 mg l-1 NAA alone formed a mass of rhizome branches. Multiple shoots of rhizome branches were induced from apical segments when rhizomes were transferred to MS medium containing 0.1 mg l-1 BA and 10 mg l-1 NAA.

In vitro morphogenetic response and distribution of endogenous plant hormones in hypocotyl segments of snapdragon (Antirrhinum majus L.).

Snapdragon seedlings, 20 mm in length, were cut into 5 segments from the cotyledon to the root, which were cultured in vitro on hormone-free MS medium. Adventitious shoot formation was highest in the basal hypocotyl segments with stimulation by the addition of BA. Endogenous cytokinins were higher in the basal hypocotyl segments than in the two upper hypocotyl segments, whereas auxin content was higher in the two upper than in the basal hypocotyl segments. Ratios of cytokinins to auxin were also the highest in the basal hypocotyl segment. A general principle in in vitro culture that a high concentration of cytokinin and a low concentration of auxin promotes the induction of shoot morphogenesis was confirmed from measurements of endogenous growth regulator concentrations.

Importance of two scales in propagating Hippeastrum hybridum by twin scaling

Abstract In twin scaling of Hippeastrum hybridum the thickness and length of the outer scale affected the rate of bulblet formation and leaf development, while those of the inner scale did not. Protuberance initiation occurred on the abaxial surface of the inner scale. However, the vascular bundles of the protuberances became united with the vascular system of the outer scale, but not with those of the inner scale. The importance of two scales in propagating H. hybridum by twin scaling was demonstrated.

Anthocyanidin malonylglucosides in flowers of Hibiscus syriacus

Abstract The methanolic formic acid extraction of the petals of Hibiscus syriacus yielded 3- O -malonylglucosides of delphinidin, cyanidin, petunidin, pelargonidin, peonidin and malvidin. The structures were determined by hydrolytic studies and 1 H NMR and FABMS examination.

Biologically active phenolics from Lilium longiflorum

Abstract The new phenolics, the trans-p -coumaroyl and the feruloyl esters of 2,3-dihydroxy-1,2-propanedicarboxylic acid and itaconic acid, were isolated from Lilium longiflorum ; the cis-p -coumaroyl ester was also detected. The biological activities of the trans-p -coumaroyl ester are described.

Comparison of bulblet formation from twin scales and single scales in Hippeastrum hybridum cultured in vitro

Abstract Protocorm-like bodies were regenerated from single scales of Hippeastrum hybridum cultured in vitro, which ultimately formed bulblets. Bulblets were directly produced from twin scales. There were morphological and physiological similarities between the protocorm-like bodies and the protocorms of orchids. The possibility of a new method for multiplication of H. hybridum was suggested as multiplication of protocorms in liquid MS medium with 1.0 mg l −1 zeatin (Z), then bulblet and shoot formation from them in liquid MS medium with 1.0 mg l −1 IAA and 1.0 mg l −1 Z.

A new biologically active phenolic from Cattleya trianaei

Abstract A new phenolic, hydroxyeucomic acid, and dopamine were isolated from Cattleya trianaei and their biological activities examined.

Comparison of the anatomy and physiology of seeds of two varieties of winged bean (Psophocarpus tetragonolobus)

Seeds of winged bean (Psophocarpus tetragonolobus L. DC) cultivar ‘KUS-1’ are largely impermeable to water and showed a very low percentage of germination, whereas seed germination in ‘KUS-8’ was higher, presumably due to greater permeability. Scanning electron microscopy revealed more extensive surface deposition in the seed coat of ‘KUS-1’ than in that of ‘KUS-8’. The cell layers of the mature seed coat structures are more highly developed than those of the immature seed coat. The seed coat structure of ‘KUS-1’ showed a compact arrangement of cell layers and a thicker hilar region including seed coat in comparison to ‘KUS-8’. Gibberellin-like substances were higher in the embryo-cotyledon of 35-day-old seeds of ‘KUS-8’ than in those of ‘KUS-1’, and they declined with maturation. Indole-3-acetic acid increased with maturation. More abscisic acid (ABA) was found in the embryo-cotyledon of ‘KUS-1’ than in that of ‘KUS-8’. The impermeability of the ‘KUS-1’ seeds may be related to the dense surface deposits, thick hilum with highly developed sclereid cells, compact arrangement of cell layers, and a greater accumulation of gibberellic acid and ABA in the embryo-cotyledon of immature and mature seeds, respectively.

Effects of photoperiod and temperature on tuberous root formation in winged bean (Psophocarpus tetragonolobus)

Abstract Effects of photoperiod and temperature on tuberous root formation in some winged bean varieties were investigated. Tuberous root formation was induced by short days. Relatively low temperature (20°C) also caused formation of tuberous root even under long days, but both lower (15°C) and higher temperatures (25°C) did not. Plants must reach a certain age for tuberous root induction by temperature. The daylength requirement for tuberous root formation in photo-sensitive and insensitive varieties seems to closely parallel that for flowering.