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991.
Summary

Leaf fragments of fig (Ficus carica L. ‘Masui Dauphine’) regenerated from in vitro shoot culture were excised and inoculated on MS medium supplemented with different combinations of 2, 4-D, TDZ, and 0.5 mM phloroglucinol. Addition of 2, 4-D induced root formation directly on the explant, and the presence of phloroglucinol significantly increased root formation. When a combination of 2, 4-D and TDZ was added to MS medium containing phloroglucinol, the explants started to produce adventitious buds at the edges. The addition of phloroglucinol was effective in inducing adventitious bud formation. Excised shoots were rooted successfully in MS medium that was either hormone free or supplemented with 1.0 mg l–1 indolebutyric acid. Regenerated plantlets were successfully established in soil after a short period of acclimatization. This is the first protocol of organogenesis and plant regeneration from vegetative organs of Ficus carica L.  相似文献   
992.
We analysed the effect of three antioxidants that have different functional mechanisms on the in vitro maturation (IVM) of porcine oocytes. Single oocyte monoculture using the hanging drop (HD) system has some advantages such as improving analysis efficiency brought by the smaller number of samples than the number of oocytes cultured in one drop. Direct effects of ligands on single oocytes could also be detected without considering the effects of paracrine factors from other oocytes. After 22 h of pre‐culture, denuded oocytes were cultured for 22 h with 0.01 and 0.1 μg/ml of L‐carnitine (LC), lactoferrin (LF) or sulforaphane (SF) in the presence/non‐presence of oxidant stress induced by H2O2 supplementation to evaluate the reducing effects against oxidative stress on nuclear maturation. As a result, compared with LC and SF, LF showed effective reduction in oxidative stress at a lower concentration (0.01 μg/ml), suggesting that LF is a more effective antioxidant in porcine oocyte IVM. Additionally, LF also increased maturation rate even in culture without H2O2. Our results clearly suggest that the HD monoculture system is useful for screening the substances that affect porcine oocyte culture.  相似文献   
993.
Chickpea is a major crop grown for its nutritional value, and it is used for both food and feed. However, terminal drought greatly reduces grain yield in many chickpea producing areas. The impacts of drought could be mitigated by adapting chickpea genotypes with higher water‐use efficiency (WUE). To assess genetic variation for WUE, contrasting genotypes were sown in two moisture regimes (well‐watered and water‐limited) and two tillage regimes (tillage and no‐tillage) in north‐western NSW across two consecutive seasons. The well‐watered and no till treatments were higher yielding than their respective rainfed and tillage treatments. Genotypes did not differ (p < 0.05) in their water use but differed significantly in their WUE, and a significant genotype‐by‐moisture treatment effect was observed. The heritability of WUE was higher under tillage (71.3% for tillage under rainfed conditions and 73.0% for tillage and irrigated conditions) than no‐till (43.3% for no till under rainfed conditions and 36.4% for no‐till and irrigated conditions), and no significant genotype‐by‐tillage interaction was observed.  相似文献   
994.
J. Q. Yan    Q. Z. Xue  Y. X. Wang 《Plant Breeding》1996,115(5):301-304
Significant differences of callus induction, green plant regeneration and culture efficiency were observed among restorer lines and their hybrids in rice. Average callus induction percentage of F1, hybrids was about twice that of their parents. Twenty doubled haploid (DH) lines that showed normal fertility with both indica and japonica CMS lines, were selected as widely compatible restorers (WCRs). TG8 derived from CPSLO17/Minghui 63 not only showed normal fertility to both indica and japonica test varieties and CMS lines, but also exhibited superior agronomic traits, in particular short plant, desired plant type, high tillerability, large panicles, good grain quality and resistance to rice blast disease. Strong heterosis for yield was observed in crosses between indica or japonica CMS lines and TG8. TG8 possessed a dominant, widely compatible gene (WCG) that was inherited from the variety CPSLO17. Results confirmed that the anther culture technique is a quick and effective way of developing widely compatible restorers in rice and that it is applicable to the direct use of intersubspecific heterosis with the three-line method.  相似文献   
995.
A 14‐month‐old Japanese Black heifer was evaluated on Day 0 (D 0) for enlargement of the right ovary (RO). Transrectal ultrasonography (TRUS) revealed that the RO was markedly enlarged and multicystic, while the left ovary (LO) was small and inactive. The presumptive diagnosis was granulosa‐theca cell tumour (GTCT), which was confirmed by markedly elevated plasma anti‐Müllerian hormone (AMH) of 4.42 ng/ml. Therefore, ovariectomy of the RO was the treatment of choice. The heifer was checked by TRUS and blood sampling on D 42, D 63 and immediately before ovariectomy on D 85. On D 42, TRUS did not show marked changes in either ovary in comparison with D 0. However, on D 63, the RO had transformed into a single cyst, and on D 85, the LO had resumed cyclic activity. The RO was extracted on D 85 by hand‐assisted laparoscopic ovariectomy to allow better control. Unexpectedly, histopathology revealed the lesion to be a fluid‐filled cystic structure, with no neoplastic proliferation of follicular epithelium that would indicate GTCT. The wall of the cystic structure consisted of collagen fibres and a few degenerated granulosa cells. The retrospective hormonal analysis revealed that the AMH concentrations had markedly dropped on D 63 and 85, which coincided with resumption of cyclicity in the LO. These findings suggest that the GTCT had self‐cured and transformed into a cyst‐like structure. The heifer then received an oestrous synchronization regime on D 105, was artificially inseminated on D 115 and became pregnant.  相似文献   
996.
997.
Azpeitia  K.  Ríos  Y.  Garcia  I.  Pagaldai  J.  Mendiola  D. 《International Aquatic Research》2017,9(2):89-106

Mussel shell biometry, nutritional quality as well as consumer sensory evaluation of experimental open ocean cultured mussel Mytilus galloprovincialis (Lamarck 1819) were analyzed and compared to that of commercial mussels from Galician Rías available in the local market. Both mussel products were of the same commercial size. In this study, open ocean mussels were significantly higher and wider than those of Galician Rías. In addition, with the exception of ash content, both mussel products showed similar biochemical composition. Regarding fatty acid profiles, however, statistical differences were detected. These differences were not fully reflected in the sensory assessment. In terms of consumer acceptability, both mussel products were considered equally satisfactory.

  相似文献   
998.
Six isonitrogenous (390 g kg?1) and isoenergetic (16.2 kJ g?1) diets with varying carbohydrate : lipid (CHO : L) ratios (202.5–1.74), were fed to triplicate groups of 25 fish in indoor recirculation system. Over 8‐week‐growth trial, best weight gain (WG), specific growth rate, feed conversion ratio, protein efficiency ratio and protein production value (P < 0.05) were observed in fish‐fed diets with CHO : L ratio of 7.5. Fish fed either the lowest (1.7) or highest (202.5) CHO : L ratio tended to produce lower (P < 0.05) growth and feed conversion efficiencies. The values of viscerosomatic index, hepatosomatic index and intraperitoneal fat ratio increased as dietary CHO : L ratios decreased. There were no significant differences in whole body and liver crude protein among dietary treatments. Whole body and liver lipid increased as CHO : L ratios decreased. Plasma cholesterol and triacylglyceride levels increased linearly as dietary CHO : L ratios decreased. Activities of glucokinase and pyruvate kinase were stimulated by elevated levels of dietary carbohydrate; however, activities of lipase (LPS) and alkaline phosphatase were stimulated by elevated levels of dietary lipid. Based on a second‐order polynomial regression analysis of WG against dietary carbohydrate and lipid levels, 275 g kg?1 of carbohydrate and 59 g kg?1 of lipid, corresponding to a CHO : L ratio of 4.7, in a diet holding 390 g kg?1 of crude protein and 16.3 kJ g?1 of gross energy, proved to be optimal for grass carp. These results indicated that utilization of dietary lipid and carbohydrate was moderate in grass carp, but the fish were a little more capable of utilizing lipid compared with carbohydrate.  相似文献   
999.
A quaternary combinatorial masking strategy was used in conjunction with photolithography to generate compositionally diverse thin-film phosphor libraries containing 1024 different compositions on substrates 2.5 centimeters square. A parallel imaging system and scanning spectrophotometer were used to identify and characterize compositions in the library with interesting luminescent behavior. Optimal compositions were identified with the use of gradient libraries, in which the stoichiometry of a material was varied continuously. This process led to the identification of an efficient blue photoluminescent composite material, Gd3Ga5O12/SiO2. Experimental evidence suggests that luminescence in this material may arise from interfacial effects between SiO2 and Gd3Ga5O12.  相似文献   
1000.

Context

High-resolution animal movement data are becoming increasingly available, yet having a multitude of empirical trajectories alone does not allow us to easily predict animal movement. To answer ecological and evolutionary questions at a population level, quantitative estimates of a species’ potential to link patches or populations are of importance.

Objectives

We introduce an approach that combines movement-informed simulated trajectories with an environment-informed estimate of the trajectories’ plausibility to derive connectivity. Using the example of bar-headed geese we estimated migratory connectivity at a landscape level throughout the annual cycle in their native range.

Methods

We used tracking data of bar-headed geese to develop a multi-state movement model and to estimate temporally explicit habitat suitability within the species’ range. We simulated migratory movements between range fragments, and calculated a measure we called route viability. The results are compared to expectations derived from published literature.

Results

Simulated migrations matched empirical trajectories in key characteristics such as stopover duration. The viability of the simulated trajectories was similar to that of the empirical trajectories. We found that, overall, the migratory connectivity was higher within the breeding than in wintering areas, corroborating previous findings for this species.

Conclusions

We show how empirical tracking data and environmental information can be fused for meaningful predictions of animal movements throughout the year and even outside the spatial range of the available data. Beyond predicting migratory connectivity, our framework will prove useful for modelling ecological processes facilitated by animal movement, such as seed dispersal or disease ecology.
  相似文献   
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