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61.
Oat β-glucan has been shown to have cholesterol, insulin and glucose lowering effects, which are related to increased viscosity of the intestinal contents. Some important factors influencing the viscosity are molecular weight, structure and concentration. To study the effect of variety and environment on β-glucan content and molecular weight of β-glucan, four oat varieties were grown in 11 different environments (location × year combinations) in a field experiment. The β-glucan content varied between 2.3 and 3.2% and the average molecular weight of β-glucan between 1.73 and 2.02 × 106 g mol−1. There was a significant difference between varieties and environments for both β-glucan content and molecular weight of β-glucan. The effect of environment was much greater on molecular weight (71%) than on β-glucan content (42%), while the effect of variety was greater on β-glucan content (23%) than on molecular weight (4%). There was also a positive significant correlation between β-glucan content and molecular weight of β-glucan (p < 0.001, r = 0.46). These results show that β-glucan content is a better target for plant breeding than molecular weight. However, both factors are important for the physiological effects of β-glucan, and selection for high β-glucan content will probably also give higher molecular weight. 相似文献
62.
63.
Fekadu Marame Chemeda Fininsa Harjit Singh Lemma Dessalegne Anhild Andersson Roland Sigvald 《Euphytica》2010,172(1):77-91
The productivity and marketable quality of hot pepper (Capsicum annuum var. annuum L.) are low in tropical regions mainly due to virus infections and lack of effective virus management strategies. The absence
of effective virus management strategies could be attributed to lack of information on virus vectors and host resistance.
Parental (P1 and P2) and progeny (F1, B1, B2 and F2) generations of five hot pepper crosses were grown in Ethiopia at three sites (Bako, Hawasa and Melkasa) to monitor number
and species of potential aphid vectors, disease incidence levels with regards to natural infections by Potato virus Y (PVY) and Ethiopian pepper mottle virus (EPMV) complex, and to determine genetic tolerance of the crop to the viruses. Disease incidence was assessed before the
flowering stage of the crop plants using visible disease symptoms due to infections by PVY and EPMV. The serological tests
revealed presence of symptomless genotypes of the crop to the virus infections. Aphid species potentially transmitting the
viruses, such as Acyrthosiphon pisum (Harris), Aphis fabae (Scopoli), and Myzus persicae (Sulzer), were identified from specimens caught by yellow water traps. The highest number of aphids from yellow water traps
was recorded at a dense foliage growth stage of the crop at Melkasa. Highly significant variation was observed among generations
of the five crosses in response to infections by PVY and EPMV complex. The most susceptible parents had the levels of disease
incidences ranging from 80 to 90%, whereas their progenies had only below 30% incidence levels. The most tolerant parent remained
symptomless to the natural infections of PVY- and EPMV-complex. Incidence levels in progenies of a cross from the most susceptible
and tolerant parents remained below 20%. Based on serological test, the proportion of PVY-positive plants ranged from 0 to
75% and of EPMV-positive plants from 0 to 25%, with 0 to 17% co-infection by the two viruses. Availability of virus sources
in the vicinity, efficiency of aphids in vectoring, weather conditions during the growth period, genetic tolerance and the
growth stage of the crop affected natural infection by PVY- and EPMV-complex. Exploitation of the genetic potential of introduced
elite genotypes and their progenies along with breeding elite local cultivars for resistance and excluding aphid vectors at
young (seedling) stage of the crop plants could be helpful for minimizing losses in yield and quality of hot pepper due to
infections by PVY- and EPMV-complex. 相似文献
64.
Dirk Jungmann Cornelia Bandow Thomas Gildemeister Roland Nagel Thomas G. Preuss Hans T. Ratte Cândida Shinn Lennart Weltje Hanna M. Maes 《Journal of Soils and Sediments》2009,9(2):94-102
Background, aim, and scope
Fenoxycarb is an insect growth regulator widely used to control a variety of pests. As a juvenile hormone analogue, it interacts with the natural hormones involved in insect development, inhibiting metamorphosis to the adult stage. Adverse effects of fenoxycarb on non-target organisms have been repeatedly observed and its rapid dissipation from water to the organic fraction of the sediment is known. The aim of this work was to investigate the impact of fenoxycarb on the development of sediment-dwelling larvae of the midge Chironomus riparius after exposure to spiked sediment. 相似文献65.
Perennial weeds are often controlled by mechanical means, which aim at stimulating axillary and adventitious buds to sprout. This happens when the apical dominance of the main shoot is removed by defoliation or when the underground system is fragmented. By repeating the measures, the result is a depletion of storage compounds, which weakens the plants and reduces their capacity to grow and reproduce. However, timing is critical. Earlier research has indicated that emergence from fragments of Sonchus arvensis cease during a period in autumn, while the seasonal pattern of sprouting in Cirsium arvense appears to be inconsistent. We studied the emergence pattern of defoliated plants with undisturbed root systems, from late summer to early spring. Potted plants grown outdoors were exhumed at regular intervals, put under forcing conditions for 4 weeks, after which shoots above and below soil level were counted and weighed together with the remaining root systems. In both species, the number and weight of emerged shoots decreased during a period in the autumn. In C. arvense, underground shoots were constantly produced during the same period, while fewer underground shoots were present in S. arvensis. For the latter species, apical dominance does not fully explain the effect; thus, endodormancy might be involved. Root weight increased until withering and did not explain the lack of emergence. Our results suggest an impaired sprouting capacity of undisturbed root systems of C. arvense and S. arvensis during September–October, which has implications for the timing and method of control of these species. 相似文献
66.
AM Kareskoski MM Rivera del Alamo K Güvenc T Reilas JJ Calvete H Rodriguez‐Martinez M Andersson T Katila 《Reproduction in domestic animals》2011,46(1):e79-e84
Seminal plasma (SP) contains several types of compounds derived from the epididymides and accessory glands. The aim of this study was to examine the protein composition of different ejaculate fractions. Trial I: fractionated ejaculates were collected from two normal and two subfertile stallions. Samples containing pre‐sperm fluid and the first sperm‐rich jets (HIGH‐1), the main sperm‐rich portion (HIGH‐2), the jets with low sperm concentrations (LOW), and a combined whole‐ejaculate (WE) sample was centrifuged, and the SP was filtered and frozen. A part of each SP sample was stored (5°C, 24 h) with spermatozoa from HIGH‐2 and skim milk extender. Sperm motility was evaluated after storage in extender mixed with the stallion’s own SP or SP from one of the other stallions (sperm from a normal stallion stored in SP from a subfertile stallion and vice versa). Protein composition was analysed using reverse‐phase liquid chromatography (RP‐HPLC), N‐terminal sequencing and mass spectrometry. The area‐under‐the‐curve (AUC) was used for quantitative comparison of proteins within fractions. Trial II: semen samples were collected from seven stallions. Fractions with the highest (HIGH) and lowest (LOW) sperm concentrations and WE samples were examined using SDS‐PAGE and densitometry. No significant differences emerged between fractions in the AUC‐values of the Horse Seminal Protein‐1 (HSP‐1) and HSP‐2 peaks, or the peak containing HSP‐3 and HSP‐4 (HSP‐3/4). Levels of HSP‐1, HSP‐2 and HSP‐3/4 were not significantly correlated with total sperm motility, progressive sperm motility or average path velocity after storage. Significant differences between ejaculate fractions in the amount of different protein groups present in SP were not found in Trial I; but in Trial II, the proteins in the 60–70 kDa range were more abundant in LOW than in HIGH and WE, indicating that this band contained proteins derived mainly from the seminal vesicles, which produce most of the SP in LOW. 相似文献
67.
Rosén LA Östman EM Shewry PR Ward JL Andersson AA Piironen V Lampi AM Rakszegi M Bedö Z Björck IM 《Journal of agricultural and food chemistry》2011,59(22):12139-12148
Rye products typically induce low insulin responses and appear to facilitate glucose regulation. The objective of this study was to investigate differences in postprandial glucose, insulin, and satiety responses between breads made from five rye varieties. Breads made from whole grain rye (Amilo, Rekrut, Dankowski Zlote, Nikita, and Haute Loire Pop) or a white wheat bread (WWB) were tested in a randomized cross-over design in 14 healthy subjects (50 g available starch). Metabolic responses were also related to the composition of dietary fiber and bioactive compounds in the breads and to the rate of in vitro starch hydrolysis. The Amilo and Rekrut rye breads induced significantly lower insulin indices (II) than WWB. Low early postprandial glucose and insulin responses (tAUC 0-60 min) were related to higher amounts of caffeic, ferulic, sinapic, and vanillic acids in the rye breads, indicating that the phenolic acids in rye may influence glycemic regulation. All rye breads induced significantly higher subjective feelings of fullness compared to WWB. A low II was related to a higher feeling of fullness and a lower desire to eat in the late postprandial phase (180 min). The data indicate that some rye varieties may be more insulin-saving than others, possibly due to differences in dietary fiber, rate of starch hydrolysis, and bioactive components such as phenolic acids. 相似文献
68.
Andersson M Ahlberg V Jensen-Waern M Fossum C 《Veterinary immunology and immunopathology》2011,142(1-2):72-80
The objective of the present study was to characterize the local immune reaction in the intestine of pigs experimentally infected with PCV2 and PPV. Archived intestinal material from an experimental study in which pigs were co-infected with a Swedish isolate of PCV2 (S-PCV2) and PPV, or a reference isolate of PCV2 (PCV2-1010) and PPV, were used. The intestinal samples were analysed by qPCR for expression of a number of selected cytokines and the overall gene expression in the intestine was screened by cDNA microarray. Analyses by qPCR showed that pigs infected with PCV2-1010/PPV displayed a significantly increased mRNA expression for IL-6 (p<0.05), IL-10 (p<0.05) and IFN-γ (p<0.05). The microarray screening revealed a strong up-regulation of IFITM3 along with several other interferon-stimulated genes (ISGs) in pigs infected with PCV2/PPV. The analyses also indicated differences between the two isolates. Fewer pigs infected with S-PCV2/PPV expressed the cytokines detected by qPCR, compared to pigs infected with PCV2-1010/PPV, and pigs infected with S-PCV2/PPV displayed a higher proportion of down-regulated genes than PCV2-1010/PPV-infected pigs. 相似文献
69.
70.
Measurement and fissuring of rice kernels during quasi-moisture sorption by image analysis 总被引:1,自引:0,他引:1
Fissuring associated with kernel elongation was evident in a moisture-adsorbing environment at 15 °C of relative humidity 88.72±0.28% with moisture content from 6% (d.b.) to 16.3% (d.b.). The average length and width of 800 kernels was measured during the sorption test using a Cervitec Grain Inspector equipped with two digital cameras. Samples were exposed to both a moisture-adsorbing and desorbing environments at 15 °C with relative humidities of 23.4±0.53%, 55.9±0.27%, 70.98±0.28% and 88.72±0.28%. On image analysis, the kernels changed in size from 5.13 to 4.84 mm in length and 2.9 to 2.73 mm in width. Both length and width changed as expected during moisture-adsorbing and moisture-desorbing tests. Fissured kernel percent was related to changes in the average length of the kernels during the moisture-adsorbing tests. The average length and fissured kernel percent of rice kernels measured by image analysis may be considered as a reliable indicator of changes in their dimensions during quasi-static moisture sorption processes. 相似文献