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Reproductive activities of salmonids are synchronized by changes in photoperiod, which control the endocrine system via the brain-pituitary-gonadal axis. Gonadotropin-releasing hormone (GnRH) in the brain regulates synthesis and release of the pituitary gonadotropins (GTHs; FSH and LH). FSH and LH in turn stimulate the production of sex steroids for oocyte growth and maturation-Inducing steroid hormones for oocyte maturation and ovulation, respectively, in female salmonids. To clarify effects of long-term photoperiod manipulations on the reproductive activity of salmonids from early recrudescence to ovulation, we Investigated the gene expression profiles of GnRH, GTHs, and vitellogenin (VTG), and plasma sex steroids in female rainbow trout (Oncorhynchus mykiss). In addition, the percentages of eyed embryos and hatched alevins were examined together with the number of ovulated eggs to evaluate the effects of photoperiod regimes on egg quality. During late summer, the mRNA levels of GnRHs, GTHalpha, and LHbeta, and the plasma level of a maturational steroid (17alpha,20beta-dihydroxy-4-pregnen-3-one; 17,20beta-P) were significantly elevated by a gradually shortened photoperiod under constant temperature, in accordance with accelerated sexual maturation. The percentages of eyed embryos and hatched alevins from fish ovulated in August were comparable to those of control fish observed in December. These results clearly indicate that syntheses of GnRHs, LH, VTG, and 17,20beta-P are effectively accelerated by a programmed long-short photoperiod regime in early recrudescent female rainbow trout, without a marked deterioration in egg quality.

We have carried out a morphological and anatomical study of the seeds of 19 taxa representing two subtribes and three genera of the tribe Oleeae (Fraxinus, Ligustrum, and Syringa) and two species of Forsythia (Forsythieae) using scanning electron and light microscopy to evaluate the usefulness of seed characteristics for the identification of systematic relationships. Considerable differences were found in seed coat morphology both among and within genera. Three types of seed coat pattern – reticulate, colliculate, and tuberculate – were recognized. The shape of the testa epidermal cells was either elongated rectangular or polygonal with smooth, striated, or infolded secondary ornamentations. The seed coat was thickest in Ligustrum spp. and thinnest in Syringa spp. The exotesta of Fraxinus species was discontinuous due to the presence of longitudinal grooves on its surface. Based on 22 seed morphological characters, cladistic analysis resolved three well‐supported clades that matched the three genera well, with Forsythia species considered as an outgroup. Ligustrum foliosum, with reticulate ornamentation, concave periclinal walls, and raised anticlinal walls, was the most distinct species within the genus, whereas the flat periclinal and sunken anticlinal walls in Syringa fauriei were unique in Syringa. Similarly, infolded secondary ornamentation was only observed in Fraxinus rhynchophylla var. densata. Although the investigated specimens represent a limited sample, the results provide valuable support for the characterization of several taxa, particularly at the species level. Moreover, surface ornamentation, epidermal cell shape, periclinal and anticlinal wall structure, and the nature and structure of the exotesta are shown to be potentially useful for cladistic analysis and for identification of species in this alliance.

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An efficient in vitro plant regeneration system was established from callus culture of Scopolia parviflora. Callus was induced from adventitious roots on B5 medium with 0.45-9.04 μM 2,4-dichlorophenoxyacetic acid (2, 4-D). In vitro plantlet regeneration was achieved on B5 medium supplemented with 44.38 μM benzyladenine (BA), 3% sucrose, and 0.38% gelrite. Plantlets were transplanted to artificial soil and grown to maturity successfully in a greenhouse. The tropane alkaloid contents in regenerated plants were analyzed using high-performance liquid chromatography (HPLC), and were found to be higher than those of adventitious roots, native growing plants, and acclimated plants. Regenerated plants from organogenic callus cultures produced a greater amount of tropane alkaloids.