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1.
Takahiro Ishii Tatsufumi Okino Yosuke Mino Hiroaki Tamiya Fuyuhiko Matsuda 《Plant Growth Regulation》2007,52(2):131-139
Starfish waste has been shown to be an effective compost material not only in the promotion of plant growth but also in terms
of having insecticidal activity. In the present study, plant growth regulation by chemicals from starfish was examined. The
aqueous fraction from a hot water extract of the starfish Asterias amurensis Lütken showed plant-growth activity, while the aqueous fraction from a methanol extract inhibited growth of Brassica campestris. The lipophilic fraction from the methanol extract also exhibited a plant growth-promoting effect. The active components
from each extract were identified. Asterubine from the hot water extract promoted plant growth. A ceramide from the lipophilic
fraction showed root growth promoting effect, and three glucocerebrosides had promotive effects on the entire plant. Asterosaponins
were identified as the main growth inhibitors in the aqueous fraction of the methanol extract. These active compounds from
starfish waste could be analyzed as potential plant growth regulators in agricultural applications in the future. 相似文献
2.
Abstract. The influences of hatchling character and rearing density on body colour at the last-nymphal stadium are investigated for the desert locust, Schistocerca gregaria . Hatchlings are divided into five groups based on the darkness of the body colour and reared either under isolated or crowded conditions. Two types of body colour variation at the last-nymphal stadium are separately analysed (i.e. the background colour and black patterns). Under isolated conditions, the background body colour is either greenish or brownish. Most individuals are greenish and the highest percentage of brownish insects is obtained from hatchlings with the darkest body colour. Under crowded conditions, the background colour is yellow or orange and the percentage of yellowish nymphs tends to decrease when they are darker at hatching. The intensity of black patterns differs depending on the body colour at hatching and subsequent rearing density. Most isolated-reared nymphs exhibit few or no black patterns but nymphs with some black patterns also appear, particularly among those that had been dark at hatching. Under crowded conditions, the black patterns become more intense when they are darker at hatching. Therefore, last-stadium nymphs with typical solitarious or gregarious body colouration appear when they have the phase-specific body colouration at hatching as well. The present results demonstrate that both body colour at hatching and rearing density during nymphal development influence body colouration at the last-nymphal stadium. 相似文献
3.
4.
SHOKO YASUKAWA HIDETOSHI KATO RYOHEI YAMAOKA HAJIME TANAKA HIROHITO ARAI SHOICHI KAWANO 《Plant Species Biology》1992,7(2-3):121-140
Abstract Volatile substances emitted from the flowers of eight Magnolia taxa ( M. sieboldii ssp. japonica, M. praecocissima var. praecocissima and var. borealis, M. tomentosa, M. salicifolia, M. obovata, M. denudata, and M. grandiflora ) and one Michelia species ( M. compressa ) (Magnoliaceae) were examined and identified using GC-MS. Volatile substances of these Magnolia and Michelia species consist primarily of monoterpenoids and sesquiterpenoids produced by the mevalonate pathway, acetogenins by the acetate-malonate pathway, and phenyl-propanoids by the shikimate pathway. These Magnolia and Michelia species all possessed various combinations of volatile monoterpenoids, acetogenins, and phenylpropanoids, except for Magnolia obovata , which emitted primarily sesquiterpenoids. Free amino acids in pollen of 12 Magnolia and one Liriodendron species were also analyzed, and their value as food sources for pollinators evaluated.
Pollinators visiting the flowers of five Magnolia species were collected in their native sites and identified. Their behaviors and roles as pollinating agents were assessed. 相似文献
Pollinators visiting the flowers of five Magnolia species were collected in their native sites and identified. Their behaviors and roles as pollinating agents were assessed. 相似文献
5.
SHIGENOBU TONÉ SHOJI TANAKA YOSHIHIRO KATO 《Development, growth & differentiation》1988,30(3):261-270
The cell cycle and cell population kinetics have been analyzed in the interdigital regions of chick limb-buds during the course of programmed cell death both in normal and the 5-bromodeoxyuridine (BrdU)-treated embryos. Our previous study has shown that a single administration of BrdU at day 6 1/3 inhibited the programmed cell death occurring in normal development of limb-buds.
Pulse- as well as continuous labelings with tritiated thymidine (3 H-TdR) were used. The results obtained from the analyses made on both normal and experimental embryos have demonstrated the presence of a particular DNA-synthetic period, around day 6 1/3, closely related to the programmed death occurring on day 7 1/3. In normal embryos, new cell populations, which did not belong to any phases of normal cell cycle, made their appearances in the process of programmed cell death. A possible correlation between programmed cell death and the cell cycle has been discussed in relation to the morphogenesis of limbs in both normal and BrdU-treated embryos. 相似文献
Pulse- as well as continuous labelings with tritiated thymidine (
6.
To elucidate the mechanism of the phosphorylation of myo-inositolin the process of phytate formation, feeding experiments oforthophosphate-32P and myo-inositol-3H in the ripening grainsof rice and wheat were performed. It was found that 32P and3H were incorporated into myo-inositol mono- and hexa-phosphates.The same results were obtained when a mixture of "cold" myo-inositolpolyphosphates was administered to the grains before feedingphosphate-32P. Based on these results it is concluded that phosphorylationof free myo-myo-inositol in the formation of phytate does nottake place in a stepwise fashion but may proceed through anunknown myo-inositol derivative. (Received August 2, 1967; ) 相似文献
7.
Integration of Agrobacterium T-DNA into a tobacco chromosome: Possible involvement of DNA homology between T-DNA and plant DNA 总被引:13,自引:0,他引:13
Shogo Matsumoto Yukihiro Ito Tsuyoshi Hosoi Yosuke Takahashi Yasunori Machida 《Molecular & general genetics : MGG》1990,224(3):309-316
Summary We established tobacco tumour cell lines from crown galls induced by Agrobacterium. Restriction fragments containing T-DNA/plant DNA junctions were cloned from one of the cell lines, which has a single copy of the T-DNA in a unique region of its genome. We also isolated a DNA fragment that contained the integration target site from nontransformed tobacco cells. Nucleotide sequence analyses showed that the right and left breakpoints of the T-DNA mapped ca. 7.3 kb internal to the right 25 by border and ca. 350 by internal to the left border respectively. When the nucleotide sequences around these breakpoints were compared with the sequence of the target, significant homology was seen between the region adjacent to the integration target site and both external regions of the T-DNA breakpoints. In addition, a short stretch of plant DNA in the vicinity of the integration site was deleted. This deletion seems to have been promoted by homologous recombination between short repeated sequences that were present on both sides of the deleted stretch. Minor rearrangements, which included base substitutions, insertions and deletions, also took place around the integration site in the plant DNA. These results, together with previously reported results showing that in some cases sequences homologous to those in T-DNA are present in plant DNA regions adjacent to left recombinational junctions, indicate that sequence homology between the incoming T-DNA and the plant chromosomal DNA has an important function in T-DNA integration. The homology may promote close association of both termini of a T-DNA molecule on a target sequence; then TDNA may in some cases be integrated by a mechanism at least in part analogous to homologous recombination.Shogo Matsumoto is on leave from Biochemical Research Institute, Nippon Menard Cosmetic Co., Ltd, Ogaki, Gifu-ken 503, Japan 相似文献
8.
Ariyuki Kagaya Yosuke Uchitomi Akira Kugaya Minoru Takebayashi Ikuo Nagaoka Mitsutaro Muraoka Norio Yokota Shigeto Yamawaki 《Journal of neurochemistry》1996,66(4):1483-1488
Abstract: We investigated the rapid and slow effects of NaF on intracellular signaling systems such as Ca2+ homeostasis and cyclic GMP (cGMP) generation in rat glioma C6 cells, using the Ca2+ -sensitive dye fura-2 and cGMP enzyme immunoassay. We found that the following: (a) NaF enhanced cGMP generation in a concentration-dependent manner. This enhancement was abolished by pretreatment with 100 µ M BAPTA tetraacetoxymethyl ester or in the presence of W-7 in a concentration-dependent manner. N G -Monomethyl- l -arginine (NMMA), a competitive inhibitor of nitric oxide synthase (NOS), also inhibited the NaF-induced generation of cGMP. These results suggest that NaF-induced cGMP generation occurs via a calcium/calmodulin- and NOS-dependent pathway. (b) The basal intracellular Ca2+ concentration ([Ca2+ ]i ) was transiently greater at 1 and 3 h after pretreatment with NaF. W-7 and W-13 antagonized the increase in [Ca2+ ]i , whereas NMMA had little effect. This suggests that the NaF-induced change in basal [Ca2+ ]i was mediated by a calmodulin-dependent pathway but was independent of a NOS-sensitive pathway. (c) The serotonin (5-HT)-induced intracellular mobilization of Ca2+ was reduced by pretreating the cells with NaF. The reduction in Ca2+ mobilization was antagonized by genistein, a tyrosine kinase inhibitor. W-7, W-5, and H-8 had no effect. Results suggest that NaF differentially regulates the cGMP generation, basal [Ca2+ ]i , and 5-HT2A receptor function in C6 glioma cells. 相似文献
9.
SATOSHI TANAKA HIDEAKI TOJO KYOKO KASAI TORU SAWASAKI CHIKASHI TACHI 《Pigment cell & melanoma research》1994,7(3):152-157
Dominant black-eyed white phenotypes are one of the most commonly observed traits in domestic animals. Their genetic control mechanisms, however, have not been elucidated. As the first step to approach the problem, we examined histologically the patterns of the distribution of pigment cells in Shiba goats (two each of day-73-postcoitum and day-112-postcoitum fetuses, and a 15-week-old kid) with the dominant black-eyed white phenotype. Melanocytes were present and fully pigmented in the choroid and the sclera of eyes, as well as in dorsal skin epidermis of the fetuses and of the kid. Melanocytes were also found in approximately 6% of the hair bulbs in the fetal dorsal skin, while the rest (94%) lacked them. Hair follicles of the kid did not harbor melanocytes except for some in the early anagen stage. The results suggest that the survival of melanocytes was inhibited specifically in the hair follicles of the Shiba goat with the dominant black-eyed white phenotype and that the ostensibly similar phenotypes in the Shiba goat and in the SI or W mutants of the mouse, where melanocytes die en route to the hair bulbs, are regulated by different mechanisms. 相似文献
10.