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571.
Shahram Shakiba Zadeh Che Roos Saad Annie Christianus Mohd Salleh Kamarudin Kamaruzaman Sijam Mariana Nor Shamsudin Vasantha Kumari Neela 《Aquaculture International》2010,18(6):1017-1026
To conquer disease problem in shrimp industries, probiotic biocontrol is a well-known remedy now. The antagonistic ability
of separated isolates from different parts of juvenile P. monodon was screened against shrimp Vibrio pathogens, V. parahaemolyticus and V. alginolyticus. The most antagonistic effect was observed for an isolate that primarily identified as Shewanella algae using conventional method followed by Biolog GN and GP microplates. Since adaptability to the host optimum cultural condition
of the target organism is of the great importance, response surface methodology, with central composite design, was applied
to assess log cell count response of S. algae in different incubation conditions. Therefore, four independent variables were assumed as: temperature (10–50°C), pH (6–10),
NaCl concentration (0–50‰) and time (12–60 h). The coefficients of multiple determinations (R
2) for the responses log cell count of S. algae being 0.827. Temperature was the merely significant independent variable that affected the log cell count of the candidate
probiotic. The candidate probiotic was revealed a reasonable growth response in quite wide range of temperature, pH and NaCl
concentration in which the maximum levels were in same range of optimum shrimp culture. 相似文献
572.
Fifteen accessions of Aegilops tauschii (DD), 10 of Ae. speltoides (SS) and 8 of the tetraploid Aegilops species sharing the U genome were used to study the influence of varied zinc (Zn) supply on development of Zn-deficiency symptoms, and on shoot dry weight and Zn concentration. Plants were grown in a Zn-deficient calcareous soil under greenhouse conditions with (+Zn = 5 mg kg—1 soil) and without (—Zn) Zn supply. Four accessions of wild tetraploid wheat, Triticum turgidum var. dicoccoides (BBAA), a group known for its high sensitivity to Zn-deficiency, were used in the experiments for comparison. As expected, the accessions of wild T. turgidum var. dicoccoides showed the highest sensitivity to Zn deficiency, and had more severe leaf symptoms of Zn deficiency (whitish-brown necrotic patches). Among the Aegilops species, leaf symptoms of Zn deficiency were, in general, more distinct in Ae. tauschii (DD) and least in Ae. speltoides (SS). Zinc efficiency, expressed as the percentage of shoot dry weight produced under conditions of Zn deficiency compared to Zn supply, averaged, 15% for T. turgidum, 32% for Ae. tauschii, 52% for Ae. speltoides and 61% for the tetraploid Aegilops species carrying the U genome. Differences in Zn efficiency among and within Aegilops species and T. turgidum were significantly correlated with the Zn amount per shoot, but not with the Zn amount per unit dry weight of shoots. The results show that Aegilops species can be exploited as an important genetic source for Zn efficiency genes, particularly Ae. speltoides var. ligustica (SS) and Ae. triuncialis (UUCC). Transfer of these genes to cultivated modern wheat may bring about a greater variation in Zn efficiency in wheat, and facilitate production of Zn-efficient modern wheat cultivars for Zn-deficient soil conditions. 相似文献
573.
Dynamics of glucose in the haemolymph of female giant freshwater prawn,Macrobrachium rosenbergii,influences reproductive and non‐reproductive moulting cycles 下载免费PDF全文
Noor Azlina Kamaruding Noraznawati Ismail Safiah Jasmani Marcy N Wilder Mhd Ikhwanuddin 《Aquaculture Research》2017,48(7):3505-3514
Glucose, when measured in haemolymph, has been found to reflect a useful predictor of energetic investment. This study evaluated the pattern of glucose in the haemolymph, with an attempt to gain a better insight into the role of glucose as nutritional source of ovarian development and energy reserves during reproductive and non‐reproductive moulting cycles. The haemolymph of female giant freshwater prawn, Macrobrachium rosenbergii, was obtained at eight different moulting stages, and levels of glucose were determined using an enzymatic colorimetric glucose‐oxidase method in parallel with a histological examination of ovarian development. Glucose levels were relatively low (0.15 ± 0.02 mg mL?1) at D0 stage, an abrupt increase (0.52 ± 0.13 mg mL?1) during premoult D1 stage and declined (0.32 ± 0.10 and 0.31 ± 0.09 mg mL?1) during premoult D2 and D3 stages, respectively; thereafter, a slight increase (0.43 ± 0.09 mg mL?1) occurred at post‐moult A stage. The progression of ovarian growth, marked by an increasing gonadosomatic index (GSI) pattern during the reproductive moulting cycle (C0–D3 stages), was directly proportionate to fluctuations in glucose levels. GSI was significantly positively correlated with glucose (R = 0.40; P < 0.05). In contrast, glucose was notably higher at post‐moult A and premoult D2 stages during non‐reproductive moulting cycle, the period during which glucose is crucial for exoskeletal chitin synthesis. At this particular stage, a negative correlation between body weight and glucose (R = ?0.36; P < 0.05) was observed. The dynamics of glucose in the haemolymph of female M. rosenbergii correlated with ovarian growth, which signify that glucose as nutritional source for vitellogenesis, and affects the body weight of this species. 相似文献
574.
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576.
Fien Degryse Rodrigo C. da Silva Roslyn Baird Ismail Cakmak Mustafa Atilla Yazici Mike J. McLaughlin 《植物养料与土壤学杂志》2020,183(2):248-259
Total Zn in fertilizer is a poor predictor of Zn availability in granular fertilizers. In this study, we compared different extraction methods using Zn fertilizers for which the agronomic effectiveness had previously been determined. Sixteen fertilizers were extracted by eight different procedures using five extractant solutions: water, 1 M ammonium acetate (pH 7.0), 74 mM EDTA (pH 7.0), 5 mM DTPA + 0.1 M MES (pH 6.2), and 0.12 M bis‐tris (pH 6). Modelling of Zn solubility and speciation was carried out with a chemical speciation program (Visual Minteq). The predicted solubilities were in good agreement with the observations, indicating chemical equilibrium. The three methods using pure water were highly correlated with each other and showed the strongest correlation with agronomic effectiveness (r = 0.81–0.90). The methods using extractants with strong pH buffering or high chelating capacity showed no or weak correlation with the agronomic effectiveness. Thus, water‐only based methods give the best indication of the availability of Zn in granular fertilizers, and are best suited for regulation or labeling of available Zn in fertilizer. 相似文献
577.
Wendy Chui Phing Lau Mohd Y. Rafii Mohd Razi Ismail Adam Puteh Mohammad Abdul Latif Ramli Asfaliza Gous Miah 《Euphytica》2017,213(1):11
Fragrance in rice is an appealing attribute to consumers. The increasing demand for fragrant rice highlights the need to develop fragrant rice variety that suit the preference of local consumers in addition to reduce fragrant rice imports. Marker-assisted backcrossing (MABC) was employed to develop advanced fragrant rice lines from the cross between MR269 and Basmati 370. MR269 is a Malaysian high-yielding rice variety but non-fragrant and was used as recurrent parent whereas Basmati 370 is a well-known fragrant traditional rice variety and was used as donor parent for the fragrance gene. Two generations of backcrosses and a generation of selfing were conducted to introgress the fragrance gene and restore the recurrent parent genome in the backcross progenies. As a result, 14 advanced fragrant rice lines were developed. These advanced fragrant rice lines carried homozygous alleles for the fragrance gene, similar to Basmati 370. The average recovery of recurrent parent genome was 88.4%. Besides being fragrant, the advanced fragrant rice lines also had most of the morphological and agronomical traits similar to MR269. Grain quality of the advanced fragrant rice lines in terms of gelatinization temperature, amylose content and gel consistency are also similar to both parents. Besides, the advanced fragrant rice lines had 2-acetyl-1-pyrroline content similar to Basmati 370. MABC approach applied in this study has successfully introgressed the fragrance gene and accelerated the recovery of recurrent parent genome in advanced fragrant rice lines, therefore these lines can be delivered to the farmers and consumers for use in due time. 相似文献
578.
Aliza D Ismail IS Kuah MK Shu-Chien AC Tengku Muhammad TS 《Fish physiology and biochemistry》2008,34(2):129-138
Copper is one of the major heavy metal pollutants found in the aquatic environment. Therefore, it is important for determining
the genes that play a key role in copper metabolism in aquatic organisms. This study, thus, aimed to identify a new copper-inducible
gene in swordtail fish, Xiphophorus helleri. Using ACP-based RT-PCR coupled with RLM-RACE, we cloned Wap65, a mammalian homologue of hemopexin gene. The gene exhibits
high identity at amino acid levels with the Wap65 gene of other fish species (42–68%) and mammalian hemopexin gene (35–37%).
In addition, ten cysteine and two histidine residues are conserved in the swordtail fish Wap65 gene. These cysteine residues
are vital for structural integrity, and histidine residues provide high binding affinity towards heme. As revealed by RT-PCR,
the gene was upregulated in swordtail fish that were exposed to copper in a dose- and time-dependent manner. Therefore, the
identification of Wap65, a mammalian homologue of hemopexin, as a new copper-inducible gene will provide greater insight into
the role of this gene in copper metabolism. 相似文献
579.
Migena Gjoni Gündemir Tomasz Szara Constantin Spataru Ismail Demircioglu Bernard Turek Georgios Petrovas Mihaela Claudia Spataru 《Anatomia, histologia, embryologia》2023,52(2):190-196
The anatomy of the sternum in birds varies according to their habitats and type of locomotion. In particular, the carina sterni manifest different shape variations. In this study, the shape of the carina sterni was investigated by means of geometric morphometrics. Birds of different types of locomotion were used in the study: flying, swimming, and terrestrial. Ducks and chickens show a wider variety of shapes. Pigeons are the species with the least differences. The margo cranialis carinae in a turkey is the flattest compared to other species. In chickens, the apex carinae is more caudally than the base of the carina sterni. The margo cranialis of the carina sterni in ducks is concave. The differences in centroid size and shape differences between species collectively are statistically significant (p < 0.0001). The most distinct shape contrast is between the duck and turkey (p: 0.0003). Form differences between the ducks and geese as well as between the chicken and turkey are statistically insignificant. There is less variation in the shape of the carina sterni among avian species representing the same type of locomotion. Although there are many comparative morphological and morphometric studies of birds, shape analysis studies revealing the interspecific differences and similarities of the sternum are very limited. Morphology of the carina sterni can be useful in taxonomic investigations. 相似文献