The moth Omphisa fuscidentalis (Lepidoptera, Pyralidae) is a univoltine insect with a larval diapause period lasting up to 9 months. We studied changes in O(2) consumption in conjunction with cytochrome c oxidase activity and cytochrome c oxidase subunit I (cox1) gene expression. O(2) consumption changed within a day, showing a supradian rhythm with a ca.12-h cycle at 25 degrees C. During the first two-thirds of the diapause period, from October to March, O(2) consumption was constant until January and then increased by March. Topical application of methoprene, a juvenile hormone analog (JHA), to diapausing larvae terminated the diapause and was associated with an increase in O(2) consumption rate at diapause termination. In JHA-treated larvae, cytochrome c oxidase activity in fat bodies was high at the beginning of the prepupal period and highest at pupation. cox1 expression in fat bodies displayed a transient peak 8 days after JHA application and peaked in the prepupal period. Taken together, our results show that the break of diapause by JHA is associated with the activation of cox1, bringing about an increase in cytochrome c oxidase activity, followed by an increase in O(2) consumption rate. 相似文献
A complete protocol for large-scale propagation of Dendrocalamus strictus Nees by somatic embryogenesis has been developed. Seeds cultured on agar-solidified Murashige and Skoog (MS) medium supplemented
with 2,4-dichlorophenoxyacetic acid (2,4-D; 3×10–5
m) produced embryogenic callus from proliferation of the embryo. Somatic embryos formed in vitro multiplied rapidly (two- to
five fold every 5 weeks) on semi-solid MS medium containing 2,4-D (1×10–5
m), kinetin (Kn) (5×10–6
m), 1-indolebutyric acid (IBA) (2×10–6
m) and soluble polyvinylpyrrolidone (PVP) (250 mg l–1), or MS with 2,4-D (1×10–5
m), 6-benzylaminopurine (BAP) (1×10–5
m), and soluble PVP (250 mg l–1). Upon transfer to MS containing 1-naphthaleneacetic acid (NAA) (5×10–6
m), Kn (5×10–6
m) and soluble PVP (250 mg l–1), the dark-green embryos developed into healthy plantlets. Unrooted shoots, if any, obtained on the multiplication media
were rooted on MS major salts reduced to half strength supplemented with NAA (3×10–6
m) and IBA (2.5×10–6
m). The rooted plants were successfully transferred to soil in polythene bags with over 80% survival. Using this methodology,
more than 100,000 plants have been produced.
Received: 16 April 1998 / Revision received: 25 September 1998 / Accepted: 10 October 1998 相似文献
Two experiments were conducted to examine the effect of including charcoal and of different processing methods of foliage from Acacia mangium in the diet on intake and performance of goats. In experiment 1, four male goats were used in a Latin square arrangement. The treatments were: control, no bamboo charcoal, and 0.5, 1.0 or 1.5 g bamboo charcoal per kg body weight (BW). The diet consisted of 10 g/kg initial BW dry matter (DM) of concentrate and Para grass, respectively. Acacia was fed adlibitum at a level of 130% of the individual fresh intake the previous day. The time for each period was 21 days with the last seven days for data collection. Adding bamboo charcoal to the diet did not increase DM intake of Acacia, total DM intake or neutral detergent fiber or acid detergent fiber digestibilities, but had a significant effect on DM, organic matter (OM) and crude protein (CP) digestibilities and nitrogen (N) retention higher values being obtained in treatments 0.5 and 1.0, significantly higher than in the control or 1.5 treatments.
In experiment 2, 42 goats were randomly allotted to 6 different treatment groups. The treatments were three different methods of processing Acacia: fresh foliage, wilted foliage or dried foliage. Each method was tested with or without adding bamboo charcoal (0.5 g charcoal/kg BW). The diet was the same as in Exp. 1. The experimental time was 12 weeks. The goats fed the diet with bamboo charcoal consumed similar amounts of total DM and DM of Acacia as the goats fed the diet without bamboo charcoal and grew significantly faster (53 and 44 g/day, respectively, with and without charcoal). The processing method of Acacia foliage had a significant effect on total DM intake and DM intake of Acacia. The highest total DM intake was obtained by goats fed wilted Acacia, significantly different from fresh and dried Acacia. The weight gain of goats fed wilted or dried Acacia was higher than that of goats fed fresh Acacia, but this difference was not significant. In conclusion, the value of Acacia mangium as a feed for goats can be improved by wilting the foliage and feeding 0.5 to 1 g/kg BW of bamboo charcoal per day 相似文献
Phenolic compounds were studied in the culms of five bamboo species collected in China: Yushania chungii, Fargesia robusta, Fargesia denudata, Fargesia rufa and Fargesia scabrida. All the species are eaten by giant panda (Ailuropoda melanoleuca). The culms contained phenolic acids and flavonoids in small concentrations, except for F. robusta, which did not contain flavonoids in detectable amounts. The species differed from each other in their phenolic composition. For example, F. rufa with the highest number of compounds clearly differed from other species. There were also differences among sampling sites, which reflect the differences among genotypes. Furthermore, there were clear ontogenetic differences in the culms: some compounds were present in mature culms but not in young (1–2 year old) culms, while the concentrations of other compounds decreased with increasing age. Over all, the composition and concentrations of soluble phenolic compounds in the bamboo culms were affected by species, age and site. 相似文献
Topical application of methoprene, a juvenile hormone analogue (JHA), induces pupation by activating the prothoracic glands (PGs) in diapausing larvae of the bamboo borer, Omphisa fuscidentalis. To determine the minimum stimulation period for PG activation, we transplanted PGs of JHA-treated larvae (donors) into non-treated larvae (recipients) on successive days after JHA treatment and observed the recipients for pupation. JHA stimulation for 1 day was sufficient to induce pupation. In recipient larvae, the hemolymph ecdysteroid titer increased transiently on day 18 after transplantation and significantly on days 24-28, prior to pupation. Secretory activity of recipient PGs increased transiently on day 16 and days 22-28. Because the recipient PG activity was too low to account for an increased ecdysteroid titer, the JHA-stimulated donor PGs must produce the major part of hemolymph ecdysteroids. In addition, the ecdysteroid produced by the donor PGs might have stimulated the recipient PGs. We examined the possible involvement of two ecdysone receptor (EcR) isoforms, OfEcR-A and OfEcR-B1, in PG activation by JHA, and found that although both isoforms were up-regulated, accompanied by an increased ecdysteroid titer in the hemolymph, the isoform mRNA levels were not altered at all before the increase in PG secretory activity. Thus, EcR expression might not be involved in feedback activation of PGs. 相似文献
Over the last decade, bamboo has emerged as an interesting plant for the treatment of various polluted waters using plant-based wastewater treatment systems. In these systems, nitrogen and phosphorous concentrations in wastewater can exceed plant requirements and potentially limit plant growth. The effects of two nutrient rates on the growth of seven bamboo species were assessed in a one-year experiment: Dendrocalamus strictus, Thyrsostachys siamensis, Bambusa tuldoides, Gigantochloa wrayi, Bambusa oldhamii, Bambusa multiplex and Bambusa vulgaris. Nutrient rates were applied with a 20:20:20 NPK fertilizer as 2.6 and 13.2 t.ha.yr?1NPK to three-year-old bamboo planted in 70 L containers. Morphological characters, photosynthetic responses, and NPK content in bamboo tissues were investigated. Under high-nutrient supply rate, the main trend observed was an increase of culm production but the culms’ diameters were reduced. For the seven species, the aboveground biomass yield tended to increase with high-nutrient rate. Increasing in nutrient rates also improved the photosynthetic activity which is consistent with the increase of nitrogen and phosphorus contents measured in plant tissues. All the bamboo species tested appears suitable for wastewater treatment purposes, but the species Bambusa oldhamii and Gigantochloa wrayi showed the higher biomass yield and nutrient removal. 相似文献