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2.
Carotenoids are not only important to the plants themselves but also are beneficial to human health. Since citrus fruit is a good source of carotenoids for the human diet, it is important to study carotenoid profiles and the accumulation mechanism in citrus fruit. Thus, in the present paper, we describe the diversity in the carotenoid profiles of fruit among citrus genotypes. In regard to carotenoids, such as β-cryptoxanthin, violaxanthin, lycopene, and β-citraurin, the relationship between the carotenoid profile and the expression of carotenoid-biosynthetic genes is discussed. Finally, recent results of quantitative trait locus (QTL) analyses of carotenoid contents and expression levels of carotenoid-biosynthetic genes in citrus fruit are shown. 相似文献
3.
Zinnat A. Begum Ismail M. M. Rahman Hikaru Sawai Satoshi Mizutani Teruya Maki Hiroshi Hasegawa 《Water, air, and soil pollution》2013,224(3):1-21
Development of aminopolycarboxylate chelants (APCs) having enhanced biodegradability is gaining increasing focus to replace the EDTA and its homologs with those used widely for the ex situ treatment of contaminated soils and are potential eco-threats. The paper reports the chelant-assisted extraction of the toxic metals (Cd, Cu, Pb, and Zn) from the metal-spiked European reference soils (Eurosoil 1 and Eurosoil 4) using biodegradable APCs, namely EDDS, GLDA, and HIDS. The effects of chelant-to-metal molar ratio, solution pH, and metal/chelant stability constants were evaluated, and compared with that of EDTA. The selectivity aptitude of the biodegradable chelants towards the toxic metals was assumed from the speciation calculations, and a proportionate correlation was observed at neutral pH. Pre- and post-extractive solid phase distributions of the target metals were defined using the sequential extraction procedure and dissolution of metals from the theoretically immobilized fraction was witnessed. The effect of competing species (Al, Ca, Fe, Mg, and Mn) concentrations was proven to be minimized with an excess of chelant in solution. The highlight of the outcomes is the superior decontamination ability of GLDA, a biodegradable APC, at minimum chelant concentration in solution and applicability at a wide range of pH environments. 相似文献
4.
Sheikh Muhammad Masum Mohammad Amzad Hossain Hikaru Akamine Jun‐Ichi Sakagami Takahiro Ishii Ichiro Nakamura Md. Asaduzzaman Prasanta Chitta Bhowmik 《Weed Biology and Management》2019,19(2):39-50
This study aimed to identify the potential allelopathic indigenous rice (Oryza sativa L. ssp. indica) varieties from Bangladesh using a performance study in a weed‐infested field and to assess the extent of allelopathic interference relative to resource competition in a glasshouse experiment. Six varieties – namely, “Boterswar,” “Goria,” “Biron” and “Kartiksail” as the most allelopathic, “Hashikolmi” as weakly allelopathic and “Holoi” as nonallelopathic – were raised following a nonweed control method. The infestation levels of weed species were calculated using Simpson's Diversity Index (SDI), which ranged from 0.2 to 0.56. However, a significant correlation coefficient (0.87, P < 0.001) was obtained from these field data compared with the root inhibition percentage from the laboratory bioassay, and the “Boterswar” variety was the most allelopathic. The interactions between the allelopathic variety “Boterswar,” weakly allelopathic variety “Hashikolmi” and Echinochloa oryzicola via a target (rice)‐adjacent (E. oryzicola) cogrowth culture were determined in a hydroponic arrangement. The relative competitive intensity (RCI) and the relative neighbor effect (RNE) values showed that the crop–weed interaction was facilitation for “Boterswar” and competition for “Hashikolmi” and E. oryzicola in rice/E. oryzicola cogrowth cultures. The allelopathic effects of “Boterswar” were much higher than the resource competition in rice/E. oryzicola cogrowth cultures. The converse was observed for “Hashikolmi.” Moreover, the mineral content of E. oryzicola was severely affected by “Boterswar”/E. oryzicola cogrowth cultures’ exudate solution. Therefore, the allelopathic potential of “Boterswar” variety might be useful for developing the weed‐suppressing capacity of rice, which will likely have a significant influence on paddy weed control. 相似文献
5.
Evaluation of shrimp polyculture system in Thailand based on stable carbon and nitrogen isotope ratios 总被引:1,自引:0,他引:1
HISASHI YOKOYAMA JUNYA HIGANO a KUMIKO ADACHI YUKA ISHIHI YOSHIHIRO YAMADA b 《Fisheries Science》2002,68(4):745-750
ABSTRACT: To quantify the contribution by cocultured animals to waste assimilation in an intensive shrimp farm in Thailand, the food web structures of the macrobenthos in a reservoir pond, a shrimp culture pond and water treatment ponds were examined using the stable C and N isotope ratio technique. Seawater for aquaculture was drawn from a creek, and stored in a reservoir pond, used for farming the banana prawn Fenneropenaeus merguiensis in culture ponds, and then recycled through treatment ponds where the green mussel Perna viridis was cultured to remove organic wastes discharged from the farming. The clam worm Nereididae sp. and the mud creeper Cerithideopsilla cingulata in the culture pond had δ 13 C values of −21.0‰ and −18.4‰, respectively, suggesting that shrimp feed (mean δ 13 C = −20.7‰) was the main food source for these species. The δ 13 C analysis also suggested that sediments (−23.7‰) in the reservoir pond and particulate organic matter (POM) (−24.0‰) and/or sediments (−25.0‰) in the treatment pond supplied carbon for most macrobenthic animals. However, green mussels in the treatment pond had a mean δ 13 C value of −20.5‰, suggesting that shrimp feed was the main food source for this species. 相似文献
6.
Feeding habits of albacore Thunnus alalunga in the transition region of the central North Pacific 总被引:2,自引:0,他引:2
Hikaru WATANABE Tsunemi KUBODERA Suguru MASUDA Shigeyuki KAWAHARA 《Fisheries Science》2004,70(4):573-579
ABSTRACT: The feeding habits of albacore Thunnus alalunga (fork length: 48.9–76.2 cm, n = 132) were examined from late spring to early autumn in relation to its northward migration in the transition region between the subtropical and subarctic fronts in the central North Pacific. Samples were collected at night using surface gill nets or during daytime pole-and-line surveys in 2001 and 2002. During May and June, albacore fed mainly on Japanese anchovy Engraulis japonicus , which accounted for 27.2%, 67.0%, and 45.5% of the total stomach contents by number ( Cn ), wet weight ( WW ), and frequency of occurrence ( F ), respectively, and secondarily on the subarctic gonatid squid Gonatopsis borealis ( Cn , 15.8%; WW , 10.8%; F , 28.8%). From July to September, albacore continued to depend on Japanese anchovy ( Cn , 48.2–52.8%; WW , 79.9–95.2%; F , 27.8–85.4%). These results corresponded well with the remarkable rebound of the Japanese anchovy stock since the 1990s. Gonatopsis borealis , the main squid prey from May to June, almost disappeared from the stomachs of albacore from July to September, probably due to the northward migration of this squid to subarctic waters in summer. The feeding impact of albacore on the Japanese anchovy stock in the transition region was conservatively estimated to be from 1400 to 2100 tons per day from late spring to early autumn. 相似文献
7.
ABSTRACT: As a possible factor leading to the low recruitment level of sea urchins in kelp forests, the inhibitory effect of 2,4-dibromophenol (DBP) and 2,4,6-tribromophenol (TBP) released from the large perennial brown algae Ecklonia kurome and Eisenia bicyclis on survival and metamorphosis of eight-armed larvae of the sea urchin Strongylocentrotus nudus was examined. The percentage of larvae that underwent metamorphosis in filtered sea water after 1 h exposure to one-half dilution of saturated dibromomethane solution (∼60 ppm) as a chemical inducer reached approximately 100% after 1 h, while that in filtered sea water containing 1 ppm TBP was reduced to 73%. This was further reduced to less than 40% in the presence of 10 and 20 ppm TBP after 2 h. In filtered sea water containing 1 and 10 ppm DBP, the proportion of metamorphosed larvae was reduced markedly to 43 and 5% after 2 h, respectively. All larvae exposed to 50 ppm TBP and to 20 and 50 ppm DBP died after 1 h. These findings suggest that DBP is more toxic than TBP for sea urchin larvae, strongly inhibiting their metamorphosis. 相似文献
8.
Shozo TOMONAGA Kenji NODA Rie SUENAGA Mari ASECHI Nami ADACHI Katsutoshi KINO Akihiro NAKAMURA D. Michael DENBOW Mitsuhiro FURUSE 《Animal Science Journal》2007,78(5):541-545
We reported that meat chicks have either a greater capability to acclimatize to novel environments, or a blunted hypothalamic‐pituitary‐adrenal response to novel environments compared with layer chicks in a commercial base. The present study compared the differences in behavior and plasma corticosterone concentrations under isolation‐induced stress between neonatal meat and layer Nagoya chicks which had been separated from the same population. Both types of neonatal chicks reared in groups were individually separated and their spontaneous activity and distress‐induced vocalizations were monitored for 10 min. The responses of the two types were remarkably different, with the meat chicks being less active than the layer chicks. Distress‐induced vocalizations were fewer in the meat than in the layer chicks. The meat chicks spent more time in a sleeping posture during isolation‐induced stress. Plasma corticosterone concentrations measured at the end of the test tended to be higher in the layer chicks than in meat ones, but not significantly. In conclusion, the selection of Nagoya chickens for meat and layer may have trends similar to those observed in commercial chickens in relation to stress susceptibility. 相似文献
9.
Katsuhiro OHKOSHI Seiya TAKAHASHI Shin-ichiro KOYAMA Satoshi AKAGI Noritaka ADACHI Tadashi FURUSAWA Jun-ichiro FUJIMOTO Yoshiaki IZAIKE Tomoyuki TOKUNAGA 《Animal Science Journal》2003,74(4):269-276
In vivo matured oocytes collected by laparoscopic follicular aspiration (LFA) from hormone treated female goats were used as recipient ooplasts for somatic cell nuclear transfer (SCNT). Japanese native (Shiba) goats were used as donor females and some donor females were used repeatedly (two or three times) at intervals of a few months. To induce synchronization of estrus, a sponge containing 0.5 g of progesterone was inserted into the vagina of each goat for 14 days. These animals were also treated with follicle stimulating hormone (FSH) in a series of 8 injections over 4 days. The first FSH injection was administered on the morning of day 9 of sponge insertion. On the morning of day 13, 50 µg of gonadotropin‐releasing hormone (GnRH) was injected into each animal. Twenty‐nine hours after GnRH injection, LFA was performed. After removal of cumulus cells, collected oocytes with the first polar body were selected and enucleated for nuclear transfer. Anterior pituitary cells isolated from an adult male Shiba goat were transfected with a DNA fragment containing the enhanced green flourescent protein gene and the puromycin resistance gene. A single donor cell was inserted into the perivitelline space of each enucleated oocyte and fusion was induced with one electric pulse of 20 V for 10 µs. The SCNT goat eggs were cultured in chemically defined medium at 38.5°C in 5% CO2, 5% O2, 90% N2 for 9 days. By LFA, 396 oocytes were collected from a total of 30 females. After removal of cumulus cells, 64% of them extruded the first polar body. The percentage of SCNT goat eggs produced using in vivo matured oocytes which developed to the blastocyst stage (20–21%) was significantly higher (P < 0.05) than that produced with in vitro matured oocytes (3–8%). 相似文献
10.
Summary For the preparation of specimens for testing the stress distribution with the photoelastic method, various techniques are applicable. In this paper the so-called glass-transition temperature method is tested on a specimen imitating the layered structure of wood. The observations made on this specimen are compared with those obtained from a specimen with isotropic properties.
Zusammenfassung Für die Herstellung von Modellen zur Untersuchung der Spannungsverteilung mit spannungsoptischen Verfahren gibt es verschiedene Techniken. In dieser Mitteilung wird das sogenannte Glas-Übergangstemperatur-Verfahren an einem Modell, das den Schichtaufbau des Holzes nachahmt, geprüft. Die Beobachtungen, die an diesem Modell gemacht wurden, werden mit jenen verglichen, die sich an einem Modell mit isotropen Eigenschaften ergaben.相似文献