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611.
612.
The effect of soybean cyst nematode (SCN) race 3 and strains of Bradyrhizobium japonkum interactions on nodulation and other agronomic characters of several soybean genotypes was investigated. Nodule weight was reduced in soybean cultivar Ogden treated with SCN plus Bradyrhizobia strains USDA 110 and 6 and on soybean cultivar Essex treated with SCN plus strain USDA 6. The result was reversed on soybean cultivar Essex treated with SCN plus strain USDA 110. The nodule number also decreased on soybean cultivars Ogden and Essex treated with SCN plus strains USDA 110 and 6. The fresh root weights of soybean cultivars Ogden and Essex treated with SCN plus strain USDA 110 were heavier than the fresh root weight of Essex treated with SCN plus strain USDA 6. Lower nitrogen content of stems and leaves was noted only in cultivar Essex treated with SCN plus strains USDA 110 and 6. Bradyrhizobia strain USDA 110 was more efficient in the initiation of nodules in cultivars Ogden and Essex than strain USDA 6. The nitrogen-fixing capacity of strain USDA 6 in Ogden was better than strain USDA 110. The differences in the agronomic performances of the various soybean genotypes were due to their degree of susceptibility to SCN and Bradyrhizobia strains and also to their genetic make-up. 相似文献
613.
614.
The epidemiology of disease of multiple aetiology: the avian respiratory disease complex 总被引:1,自引:0,他引:1
F T Jordan 《The Veterinary record》1972,90(20):556-562
615.
Background
Kinome profiling aims at the parallel analysis of kinase activities in a cell. Novel developed arrays containing consensus substrates for kinases are used to assess those kinase activities. The arrays described in this paper were already used to determine kinase activities in mammalian systems, but since substrates from many organisms are present we decided to test these arrays for the determination of kinase activities in the model plant species Arabidopsis thaliana. 相似文献616.
617.
618.
I Barja G Silván S Rosellini A Piñeiro MJ Illera JC Illera 《Reproduction in domestic animals》2008,43(6):701-707
The determination of gender in wild animals is essential for behavioural and ecological studies, and also for conservation. The objectives of this study were (i) the determination of gender in faecal samples of Iberian wolf based on the differential concentrations of sexual steroid hormones (SSH) and (ii) to analyse the profiles of SSH in males and females (considering the gender determination carried out previously) during the non‐reproductive and reproductive periods. The quantification of androgens (testosterone, T), progestin (progesterone, P) and oestrogen (oestradiol, E) was conducted by means of enzyme immunoassay. The k‐means conglomerate analysis showed that the 59 faecal samples grouped into three different conglomerates, considering SSH levels. Groups 1 and 2 showed higher levels of T than group 3. Therefore, the faecal samples included in groups 1 and 2 (17 samples) corresponded to males and those of group 3 (42 samples) to females. The levels of T + P + E and T/P were higher in the group of males than in the group of females. The results of this study also showed that levels of T in males were higher during the reproductive period than in the non‐reproductive period. However, the concentrations of P and E turned out to be higher during the non‐reproductive season. In females, the levels of the three hormones (T, P and E) were higher during the reproductive period. 相似文献
619.
620.
In the current study, we determined the seroprevalence of Toxoplasma gondii, Sarcocystis neurona, and Encephalitozoon cuniculi in three species of lemurs from St. Catherines Island, Georgia. Serum samples were tested from 52 ring-tailed lemurs (Lemur catta), six blue-eyed black lemurs (Eulemur macaco flavifrons), and four black and white ruffed lemurs (Varecia variegata variegata) using an agglutination assay. Three ring-tailed lemurs (5.8%) were positive for T. gondii (titer of 1:50); one ring-tailed lemur (1.9%) and one black and white ruffed lemur (25%) were positive for S. neurona (titers of 1:1000); and one ring-tailed lemur (1.9%) was positive for E. cuniculi (titer of 1:400). All blue-eyed black lemurs were negative for antibodies to T. gondii, S. neurona, and E. cuniculi. This is the first detection of antibodies to T. gondii in ring-tailed lemurs and antibodies to S. neurona and E. cuniculi in any species of prosimian. 相似文献