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排序方式: 共有825条查询结果,搜索用时 93 毫秒
821.
Jose Luis Sánchez‐Salgado Mohamed Alí Pereyra Concepción Agundis Oscar Vivanco‐Rojas Claudia Sierra‐Castillo Juan José Alpuche‐Osorno Edgar Zenteno 《Aquaculture Research》2017,48(8):4001-4011
Several lectins have been found in crustaceans, and it has been suggested that they play roles in cell signalling, cell–cell interaction, protein synthesis and pathogen recognition. These functions are performed through their specificity for carbohydrates. This review analyses the carbohydrate specificity, tissue distribution and participation in the immune responses of lectins in crustaceans. Furthermore, we explore some data showing that lectin expression seems to be stimulated by pathogens, favouring crustacean survival. 相似文献
822.
Effects of protein and carbohydrate levels on survival,consumption and gonad index in adult sea urchin Strongylocentrotus purpuratus (Stimpson 1857) from Baja California,Mexico
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A greater understanding of dietary protein and carbohydrate levels with regard to gonad production in Strongylocentrotus purpuratus would increase our nutritional knowledge of this sea urchin and guide the development of formulated diets for such aquaculture target species. A total of 255 purple sea urchins were captured from Ensenada Bay, Mexico, and maintained in 200‐L tanks for 9 weeks. Formulated diets that contained 30%, 26%, 23%, 20% and 17% of protein and 42%, 46%, 50%, 54% and 58% carbohydrates were offered ad libitum. Survival was affected by diets; urchins that were fed high‐protein–low‐carbohydrate diet experienced decreased survival. No significant differences were found in gonad index, but gonad production efficiency was lower in urchins that were fed a medium‐low‐protein–medium‐high‐carbohydrate diet. Urchins that were fed high carbohydrate levels utilized protein more efficiently and showed better digestibility of the diet and protein. These data suggest that all of our diets support gonad growth, but in terms of consumption, a diet that contains protein levels of 17% and 23% with carbohydrate levels of 50% and 58% are beneficial for S. purpuratus. 相似文献
823.
John Bamberg Charles Fernandez Alfonso del Rio 《American Journal of Potato Research》2017,94(6):583-587
Potato has about 100 wild species relatives that are multiplied in the form of botanical seed populations by genebanks, and distributed for use in research and breeding, so factors that affect long term seed germination are of interest. In 1987 the US Potato Genebank conducted routine seed multiplication on 127 populations of 31 species as greenhouse-grown potted plants. Half of the parent plants in each population were given two doses of liquid fertilizer in addition to the standard slow-release granular fertilizer which had been mixed into the medium for all plants. Plants with this extra liquid fertilizer application grew larger, and produced significantly more fruit and seeds. However, seeds from parents fertilized extra did not have improved seed weight or germination after 26 years of storage. We conclude that optimizing the fertilizer regime used on parent plants, while doubling the average seed yield, does not result in higher quality seeds. 相似文献
824.
Effectiveness of quantitative resistance conferred by the genetic background of pepper in the control of root‐knot nematodes and influence onto durability of Me1‐ and Me3‐resistant genes in greenhouse conditions
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Fulgencio Sánchez‐Solana Caridad Ros María del Mar Guerrero Victoriano Martínez Carmen María Lacasa Ana Hernández Alain Palloix Alfredo Lacasa 《Plant Breeding》2017,136(5):759-766
In pepper (Capsicum annuum), the major genes (R‐genes) Me1 and Me3 confer resistance against root‐knot nematodes (Meloidogyne spp.). The combination of R‐genes and quantitative resistance factors in the same genotype is considered a good breeding strategy for increasing the durability of R‐genes. To ascertain this hypothesis, five pepper inbred lines, differing in their quantitative resistance level, were combined with Me1 or Me3 genes in F1 hybrids. The resistance of inbred lines and F1 hybrids was evaluated in a greenhouse with soil naturally infected by M. incognita in two successive growing years. In both years, lines carrying Me3 were less infected by the nematode when combined with quantitative resistance. An increase in nematode infection was observed in the second growing year in lines carrying Me1 or Me3, independently of quantitative resistance. The infection level recorded in inbred lines without R‐genes was similar in both years. The effectiveness of quantitative resistance controlling M. incognita is confirmed in greenhouse conditions, although the durability of Me1 and Me3 when combined with quantitative resistance factors was not seen to increase. 相似文献
825.
Carmelo S del Castillo Md Iftekharul Wahid Takeshi Yoshikawa Taizo Sakaia 《Fisheries Science》2008,74(1):174-179
ABSTRACT: Among several marine antagonistic bacteria isolated from the sea water of Kagoshima Bay, Pseudoalteromonas sp. A1-J11 was found to produce anti- Vibrio substances. The anti- Vibrio substances were extracted from the culture supernatant of the strain with chloroform and isolated using reverse-phase (Cosmosil 75C18 -OPN) column chromatography followed by high-pressure liquid chromatography (Mightysil RP-18 GP Aqua). Purified substances, designated as AVS-03 a , c and d showed similar ultraviolet absorption spectra with λmax at 215, 235, 315 and 327 nm in methanol. AVS-03 d , the major anti- Vibrio substance, was thermostable up to 100°C and pH stable over a pH range higher than 4.0, and also showed strong inhibitory activities, specifically against Vibrio harveyi strains. 相似文献