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391.
Joseph M. K. Mulema Joana G. Vicente David A. C. Pink Alison Jackson Duncan O. Chacha Lusike Wasilwa Zakary M. Kinyua Daniel K. Karanja Eric B. Holub Paul Hand 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(2):427-438
A study was conducted in the East African countries of Kenya, Tanzania and Uganda in the months of July and August 2009 with
the objectives of assessing the status of black rot and race structure of Xanthomonas campestris pv. campestris in the three countries. Samples infected with black rot were collected from farmers’ fields mainly from Brassica oleracea crops (broccoli, cabbage, cauliflower and kales). A total of 399 farms were surveyed of which 260 were from Kenya, 91 from
Tanzania and 48 from Uganda. Following successful isolations, a total of 249 isolates of the causal agent, Xanthomonas campestris pv. campestris were recovered. Pathogenicity of all isolates was confirmed on B. oleracea susceptible cultivars Copenhagen Market F1 and Wirosa F1. Sixty of the 250 isolates were race-typed using a differential
set Brassica spp. Only two races, 1 (Kenya and Tanzania) and 4 (Kenya, Tanzania and Uganda) were observed however, another race (5) was
observed from one isolate recovered from a B. rapa sample obtained from Tanzania in 2003. Genomic fingerprinting with repetitive-PCR revealed clusters that did not depict significant
correlations between isolates and geographical location, isolates and host adaptation or isolates and race. However, it did
demonstrate existence of genetic differences within the East African X. campestris pv. campestris population indicating that it is not a similar clonal population of the same genetic background. 相似文献
392.
Peter W. Gous Anke Martin Wendy Lawson Alison Kelly Glen P. Fox Mark W. Sutherland 《Euphytica》2012,185(1):37-45
Barley (Hordeum vulgare) is a major feed source for the intensive livestock industry. Competitiveness against other cereal grains depends largely
on the price per unit of expressed feed quality. The traits which contribute to feed quality in barley are largely quantitative
in nature but little is known about their genetic control. A study to identify the quantitative trait loci (QTLs) associated
with feed quality was performed using a F6-derived recombinant inbred barley population. Samples from each line were incubated
in the rumen of fistulated cattle, recovered, washed and dried for determination of in situ dry matter digestibility. Additionally,
both pre- and post-digestion samples were analysed to quantify the content of key quality components relating to acid detergent
fibre, total starch and protein. The data was used to identify trait-associated QTLs. Genetic analysis identified significant
QTLs on chromosomes 2H, 5H and 7H. Genetic markers linked to these QTL should provide an effective tool for the selection
and improvement of feed barley in the future. 相似文献
393.
Katia T. Stefanova Alison B. Smith Brian R. Cullis 《Journal of Agricultural, Biological & Environmental Statistics》2009,14(4):392-410
We report an analysis of a series of uniformity field trials using the technique proposed by Gilmour, Cullis, and Verbyla.
In particular, we clarify the role of the sample variogram and present a range of enhanced graphical diagnostics to aid the
spatial modeling process. We highlight the implications of the presence of extraneous variation related to commonly used agronomic
practices, such as serpentine harvesting. 相似文献
394.
395.
Doust RT Clarke SP Hammond G Paterson C King A 《Journal of the American Veterinary Medical Association》2006,228(3):389-391
CASE DESCRIPTION: A 4-month-old Bernese Mountain Dog was examined because of shifting hind limb lameness and lethargy of 2 weeks' duration. CLINICAL FINDINGS: The lameness was attributed to hypertrophic osteodystrophy. Portosystemic shunting was suspected on the basis of low serum albumin concentration and high serum bile acids concentration, and an intrahepatic shunt was identified ultrasono-graphically. Celiotomy was performed, and the shunt was partially closed with a cellophane band. During follow-up ultrasonography 7 months later, dilation of the left renal pelvis and proximal portion of the left ureter was identified. During exploratory celiotomy, the left ureter was found to pass dorsal to the caudal vena cava, and circumcaval ureter was diagnosed. TREATMENT AND OUTCOME: The ureter was transected, repositioned ventral to the vena cava, and anastomosed. Follow-up ultrasonographic examinations revealed gradual resolution of the hydronephrosis and hydroureter. CLINICAL RELEVANCE: Findings suggest that circumcaval ureter should be considered in the differential diagnosis for hydronephrosis and hydroureter in dogs. Partial obstruction of the middle segment of the ureter on ultrasonograms or contrast radiographs should increase the index of suspicion for this condition. 相似文献
396.
Shaked Y Ciarrocchi A Franco M Lee CR Man S Cheung AM Hicklin DJ Chaplin D Foster FS Benezra R Kerbel RS 《Science (New York, N.Y.)》2006,313(5794):1785-1787
The contribution of bone marrow-derived circulating endothelial progenitor cells (CEPs) to tumor angiogenesis has been controversial, primarily because of their low numbers in blood vessels of untreated tumors. We show that treatment of tumor-bearing mice with vascular disrupting agents (VDAs) leads to an acute mobilization of CEPs, which home to the viable tumor rim that characteristically remains after such therapy. Disruption of this CEP spike by antiangiogenic drugs or by genetic manipulation resulted in marked reductions in tumor rim size and blood flow as well as enhanced VDA antitumor activity. These findings also provide a mechanistic rationale for the enhanced efficacy of VDAs when combined with antiangiogenic drugs. 相似文献
397.
398.
399.
Haraguchi M Gorniak SL Ikeda K Minami Y Kato A Watson AA Nash RJ Molyneux RJ Asano N 《Journal of agricultural and food chemistry》2003,51(17):4995-5000
Natural intoxication of livestock by the ingestion of Ipomoea carnea (Convolvulaceae) sometimes occurs in tropical regions of the world. Polyhydroxylated alkaloids were isolated from the leaves, flowers, and seeds of the poisonous plant and characterized. Chromatographic separation of the leaf extract resulted in the isolation of swainsonine (1), 2-epi-lentiginosine (2), calystegines B(1) (3), B(2) (4), B(3) (5), and C(1) (6), and N-methyl-trans-4-hydroxy-l-proline (7). The contents of 1 in the fresh leaves and flowers were 0.0029 and 0.0028%, respectively, whereas the contents of 1, 3, and 4 in the seeds were approximately 10 times higher than those in the leaves and flowers. Alkaloids 3, 4, and 6 showed a potent inhibitory activity toward rat lysosomal beta-glucosidase, with IC(50) values of 2.1, 0.75, and 0.84 microM, respectively, and alkaloid 5 was a moderate inhibitor of alpha- and beta-mannosidases. Although alkaloid 1 is known as a powerful inhibitor of lysosomal alpha-mannosidase (IC(50) = 0.02 microM), alkaloid 2, which has been thought to be an intermediate in the biosynthesis of 1, was also a potent inhibitor of alpha-mannosidase with an IC(50) value of 4.6 microM. 相似文献
400.
Yushu Zhang Alison Carswell Rui Jiang Laura Cardenas Deli Chen 《Soil Science and Plant Nutrition》2020,66(3):481-488
ABSTRACT Biological nitrogen fixation (BNF) is an important nitrogen source for both N2-fixers and their neighboring plants in natural and managed ecosystems. Biological N fixation can vary considerably depending on soil conditions, yet there is a lack of knowledge on the impact of varying soils on the contribution of N from N2-fixers in mixed swards. In this study, the amount and proportion of BNF from red clover were assessed using three grassland soils. Three soil samples, Hallsworth (HH), Crediton (CN), and Halstow (HW) series, were collected from three grassland sites in Devon, UK. A pot experiment with 15N natural abundance was conducted to estimate BNF from red clover, and the proportion of N transferred from red clover to the non-N2 fixing grass in a grass-clover system. The results showed that BNF in red clover sourced from atmosphere in the HH soil was 2.92 mg N plant?1, which was significantly lower than that of the CN (6.18 mg N plant?1) and HW (8.01 mg N plant?1) soils. Nitrogen in grass sourced from BNF via belowground was 0.46 mg N plant?1 in the HH soil, which was significantly greater than that in CN and HW soils. However, proportionally there were no significant differences in the percentage N content of both red clover and grass sourced from BNF via belowground among soils, at 65%, 67%, 65% and 35%, 27%, 31% in HH, CN, and HW, respectively. Our observations indicate that the amount of BNF by red clover varies among grassland soils, as does the amount of N sourced from BNF that is transferred to neighboring plants, which is linked to biomass production. Proportionally there was no difference among soils in N sourced from BNF in both the red clover plants and transferred to neighboring plants. 相似文献