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31.
V. M. Rodríguez P. Soengas E. Cartea T. Sotelo P. Velasco 《Journal of Agronomy and Crop Science》2014,200(3):183-190
Statistical models predict that global warming will have a negative impact in crop yields in the next decades. Especially vulnerable are winter crops such as kales or cabbages (Brassica oleracea L.). We evaluated the impact of high temperatures in morphological and biochemical traits of a B. oleracea core collection during early development. When grown at 30 °C, plants showed a reduction in chlorophyll content, early vigour and biomass compared with values observed on plants grown at 20 °C. Likewise, the total content of glucosinolates shows a reduction at high temperatures. The alboglabra group showed the best general performance at 30 °C for both morphological traits and glucosinolate content. Based on a cluster analysis, we selected four populations (MBG0072, MBG0464, MBG0535 and HRIGRU5555) as the most promising to be used in further breeding programs for heat tolerance. 相似文献
32.
Devkota B Sasaki M Matsui M Amaya Montoya C Miyake Y 《The Journal of reproduction and development》2006,52(3):329-334
Previously, we reported the normal postnatal developmental changes in immunohistochemical localization of alpha-smooth muscle actin (SMA) and vimentin in the bovine testis. In this study, we demonstrate the alterations of these cytoskeletal proteins in the bovine cryptorchid testis as compared to the contralateral scrotal testis during postnatal development. Seminiferous peritubular alpha-SMA did not appear in the cryptorchid testis until 8 months of age, except for very weak intermittent filaments in relatively larger seminiferous tubules. However, a similar peritubular pattern was observed in the 18-month-old cryptorchid and scrotal testes. Moreover, weak expression of alpha-SMA in the straight tubules and rete testes at 5 months of age did not improve until 18 months of age in the cryptorchid testes. The Sertoli cell vimentin in the cryptorchid testes revealed a highly immature pattern at 5 months of age, a pattern similar to a transforming pattern with infranuclear vimentin extensions at 8 months of age, and a pattern that was almost a transforming pattern, but with considerable weakening of the vimentin filaments, at 18 months of age. In conclusion, cryptorchidism may cause considerable delay in testicular myoid cell differentiation and in attainment of the transforming pattern of the Sertoli cell vimentin, which weakens and fails to attain the mature pattern in the cryptorchid testis. These alterations may be related to the structural immaturity and functional failure of postnatally developing bovine testes exposed continuously to body heat. 相似文献
33.
Alejandro Martínez-Bilbao Amaya Ortiz-Barredo Emilio Montesinos Jesús Murillo 《Euphytica》2012,188(2):273-283
Host resistance is a key method for the integrated management of apple scab caused by Venturia inaequalis, which is one of the most important diseases of apple. Artificial inoculation of 92 cider apple cultivars with a mixed inoculum of V. inaequalis identified 19 weakly resistant and 19 resistant cultivars. Twelve of these resistant cultivars were previously classified as having low susceptibility to fire blight, and four of them showed complete or weak resistance to races (1), (1, 6) and (6, 7, 13) of V. inaequalis. The analysis of a selection of 72 cultivars for 6 years under field conditions identified 14 cultivars that were classified as resistant to apple scab under high disease pressure involving one to six Mills periods of severe risk of infection each year. Eight out of these 14 cultivars previously showed high levels of resistance to fire blight, which would allow the incorporation of genetic resistance in the integrated production of cider apples in Spain through their use in breeding programs. 相似文献
34.
35.
Celia Martínez-Alonso Angelo Kidelman Isabel Feito Tania Velasco Ricardo Alía Maria Jo?o Gaspar Juan Majada 《New Forests》2012,43(5-6):651-663
Due to the high economic importance of Pinus pinaster Ait., there is considerable interest in developing, improving and extending the use of its families for mass clonal propagation and in breeding programmes. In the current study, we evaluated shoot growth, rooting ability and mini-cuttings production of P. pinaster in response to nitrogen fertilization and seasons. We compared eight half-sib families of P. pinaster from Asturias and Galicia (Northern Iberian Peninsula), searching for useful parameters and growing conditions to be included in a mass propagation program for clonal family forestry. We fertilized P. pinaster seedling mother plants kept in a greenhouse with three levels of nitrogen: high (HN), medium (MN) and low (LN) to evaluate rooting ability of mini-cuttings. In addition, we evaluated the maximal potential production of rooted mini-cuttings considering nine cycles of propagation over 1?year, also using three levels of nitrogen. The HN treatment significantly influenced the rooting process, with length, area and volume of roots all being positively affected. Spring was the most favourable season for mini-cuttings in the HN treatment. This study provides valuable new information to optimize the clonal propagation protocol for P. pinaster and shows that the mini-cuttings technique has great potential in mass scale cloning, providing high quality sprout production and well-formed new plants. 相似文献
36.
37.
The orbital region of the cortex in the cat is essential to the occurrence of spontaneous spindle bursts and thalamically induced recruiting responses, observed in both cortex and thalamus. Ablations of the entire dorsal convexity, and of the mesial and cingulate regions of the cortex, failed to interfere with the spindle bursts and recruiting responses, whereas ablations confined to the orbital cortex alone abolished completely these potentials in the cortex and thalamus. Therefore, the orbital cortex appears to be the only region of the neocortex to play a crucial role in the regulation of thalamocortical synchronizing and integrating functions. These functions are believed to be associated with a nonspecific system governing internal inhibition which manifests itself in inattention, drowsiness, and sleep. 相似文献
38.
Structure of RNA in ribosomes 总被引:4,自引:0,他引:4
The 50S and 30S ribosomes and 23S and 16S RNA were hydrolyzed with ribonuclease A. The rate constants and number of fragments produced were determined for each reaction. The conformation of 23S RNA changes when the RNA is extracted from the ribosome. Specific regions of the RNA in 50S and 30S ribosomes are protected from hydrolysis by the ribosomal proteins. 相似文献
39.
Carmona M Zalacain A Pardo JE López E Alvarruiz A Alonso GL 《Journal of agricultural and food chemistry》2005,53(10):3974-3979
A dehydration postharvesting treatment is necessary to convert Crocus sativus L. stigmas into saffron spice. Three different dehydration treatments were evaluated: dehydration at room temperature; dehydration with hot air at different temperatures (70, 90, and 110 degrees C); and dehydration following traditional processing in Castille-La Mancha (Spain) with three different heating sources (vineshoot charcoal, gas cooker, and electric coil). The time (between 28 and 55 min) and mean temperature (between 54 and 83 degrees C) conditions for traditional dehydration were established for the first time. The highest coloring strength was obtained when saffron was submitted to higher temperatures and lower times. These findings may be supported by the fact that samples dehydrated at high temperature were more porous than those dehydrated at room temperature, as was observed by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The higher the temperature during the process, the higher the proportion of trans-crocetin di-(beta-D-gentibiosyl) ester, although trans-crocetin (beta-D-glucosyl)-(beta-D-gentibiosyl) and trans-crocetin di-(beta-D-glucosyl) ester decrease while cis-crocins did not change significantly. A thermal aging process reveals that the trans-crocetin di-(beta-D-gentibiosyl) ester increases when saffron is resubmitted to a heating treatment before it is decomposed by the extreme conditions. The picrocrocin extinction during the aging process does not imply a consistent generation of safranal. 相似文献
40.
Summary Seed colour is considered as an important breeding objective in Ethiopian mustard and other Brassica species, but its measurement is usually subjective rather than objective. For this reason we studied the potential of visible reflectance spectroscopy (VRS) combined with factorial analysis and multivariate calibration to predict seed colour in seeds of Ethiopian mustard. A total of 8331 samples were screened in the range 400–2500 nm with a near infra-red reflectance spectroscopy (NIRS) spectrophotometer. A common factor analysis was performed using 1148 samples and spectral data from 400 to 700 nm. It was found that four common factors explained 99.9% of the variance. Three of these factors were associated with colour characteristics of the seeds. Factor 1 separated yellow, yellow-brown and brown seeded samples, factor 3 separated brown from reddish-brown samples and factor 4 separated complete yellow from greenish-yellow samples. Calibration equations were developed for each factor, which allowed seed colour in those samples not included in factor analysis to be predicted. This study demonstrated that seed colour prediction can be incorporated into NIRS routine analysis with instruments that incorporate the visible spectral region. 相似文献