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21.
Contrasting patterns of variation in weedy traits and unique crop features in divergent populations of US weedy rice (Oryza sativa sp.) in Arkansas and California 下载免费PDF全文
22.
Serologic and fecal markers to predict response to induction therapy in dogs with idiopathic inflammatory bowel disease 下载免费PDF全文
23.
Adil E
A Bala Robert Delorme Albert Kollmann Lucien Kerhoas Jacques Einhorn Paul-Henri Ducrot Danielle Aug 《Pest management science》1999,55(7):745-750
A methanol extract of roots of Lasiosiphon kraussianus (Meisn) (Thymelaeaceae) showed potent insecticidal activity against Aphis gossypii (Glov) and Drosophila melanogaster (Meig). Bioassay-driven fractionation of this extract led to the isolation and characterisation of two known daphnane diterpenoids: Excoecaria toxin (1) and wikstrotoxin D (2) . The two natural products were inferior to methomyl in activity against A gossypii and Myzus persicae (Sulz) in contact assays but were superior in ingestion assays against D melanogaster. This is the first report on insecticidal activities of compounds 1 and 2 . AChE was insensitive to the two natural products. © 1999 Society of Chemical Industry 相似文献
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25.
B Eliás G Boros M Albert S Tuboly P Gergely L Papp I Barna Vetró P Rafai E Molnár 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1990,52(4):677-688
The role of dermonecrotic toxin (DNT) of Bordetella bronchiseptica and Pasteurella multocida, purified by repeated chromatography in Sephacryl S-200 gel, in the pathogenesis of atrophic rhinitis (AR) of swine was studied bacteriologically, clinically and pathologically. Two-week-old specific pathogen-free (SPF) piglets were parenterally treated with 30 micrograms of DNT 3 times at 2-day interval and 7-week-old piglets were treated with 15 micrograms of DNT twice a week for 5 weeks. In 2- to 3-week-old piglets, both B. bronchiseptica DNT and P. multocida DNT produced nasal turbinate lesions with similar severity, characterized by damage of the cilia, epithelial metaplasia, intensive proliferation of osteoblasts, regressive changes, and diffuse osteocytic osteolysis. In 7- to 12-week-old piglets, treatment with B. bronchiseptica DNT failed to produce progressive changes in the nasal turbinates. Histopathological examination revealed osteogenic processes and osteoid synthesis besides the proliferation of osteoblasts and mild osteocytic osteolysis. Moreover, severe gross pathological lesions developed in the stomach, liver, kidneys, and lymphoid organs. The piglets' appetite and body weight gain gradually decreased during the DNT treatment and in the last week when the toxic signs appeared. Treatment of 7- to 12-week-old piglets with P. multocida DNT resulted in progressive AR. Histopathologically, diffuse osteocytic osteolysis was observed in the nasal turbinates. Neither clinical signs nor pathological lesions of the visceral organs developed in these piglets. The authors emphasize that the DNT of B. bronchiseptica basically differs from that of P. multocida in biological properties, though there are certain similarities between the DNTs. 相似文献
26.
Fernando Silla Álvaro Camisón Andrea Solana Héctor Hernández Guillermo Ríos Miguel Cabrera Dámaris López Albert Morera-Beita 《Annals of Forest Science》2018,75(4):95
Key message
Quercus secondary forests show a gradual transition toward mixed forests, with sweet chestnut ( Castanea sativa ) becoming increasingly abundant in the western Spanish Central System. Additionally, in chestnut-dominated stands, it shows a certain resistance to competitive displacement by Quercus pyrenaica . Our results partially refute the traditional view that C. sativa is unable to recruit in the absence of cultural inputs.Context
Sweet chestnut, Castanea sativa, is a component of European broadleaf forests and is one of the most managed trees. Due to a reduction in cultural inputs, chestnut-dominated stands tend to be invaded by other species, and it is unclear how chestnut is able to persist in natural mixed forests.Aims
Our work aimed to identity the main factors that limit the establishment of C. sativa and to analyze the recruitment and mortality processes of C. sativa trees.Methods
The age, growth ring patterns, regeneration density, and the spatial structure of trees and saplings in 11 plots in the Spanish Central System were analyzed.Results
Chestnut seedling density increased with C. sativa basal area, but transition toward the sapling stage appeared limited owing to light availability. In Quercus pyrenaica secondary forests, sparse canopies did not constrain chestnut regeneration, and in old chestnut stands, C. sativa showed a certain resistance to competitive displacement. By contrast, mixed young coppices showed a high mortality, most likely due to competition with other vigorous resprouters.Conclusion
Quercus secondary forests showed a gradual transition toward mixed forests with sweet chestnut becoming increasingly more abundant. In old stands, C. sativa is likely to persist under a gap-phase mode of regeneration. Our results partially refute the traditional view that C. sativa is unable to recruit in the absence of cultural inputs.27.
Yin-Ming Li Rufus L. Chaney Albert A. Schneiter Jerry F. Miller Elias M. Elias James J. Hammond 《Euphytica》1997,94(1):23-30
Cadmium (Cd) level in nonoilseed sunflower (Helianthus annuus L.), flax (Linum usitatissimum L.), and durum wheat (Triticum
turgidum L. var. durum) grown on uncontaminated, alkaline soils has exceeded limits established in Northern Europe. Separate
field experiments were conducted to investigate variability of grain Cd levels among sunflower, durum wheat and flax germplasm,
and to seek an efficient screening method for future breeding. There were large variations in leaf Cd concentration among
200 sunflower lines. These lines performed more consistently for Cd uptake at the R5 stage than at the V8 stage across 4 locations
with markedly differing soils. Cd concentration in V8 leaves was not related to Cd in grain. The positive correlation between
R5 leaf Cd and kernel Cd level was obtained from nonoilseed hybrid (Sigco 954) (R2; = 0.74**), and 200 lines (R2 = 0.44**) tested over 4 locations in 2 field trials, respectively. This indicates that an efficient and low cost screening
method can be developed for genotype selection, but plants must be grown to the R5 stage. A preliminary evaluation of 30 durum
wheat and 74 flax lines indicated large variations in grain Cd level of durum wheat and flax. Grain Cd concentration ranged
from 0.11 to 0.34 mg Cd kg-1 DW for durum wheat, and 0.14 to 1.37 mg Cd kg-1 DW for flax, respectively. This variability indicates that breeding for low grain Cd in durum wheat and flax should be feasible.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
28.
Saeid Mobini Hamid Khazaei Thomas D. Warkentin Albert Vandenberg 《Plant Breeding》2020,139(6):1181-1189
The aim of this study was to reduce the length of the breeding cycle for faba bean by accelerating seed setting. We examined the mode and time of exogenous 6-benzylaminopurine (BAP) (cytokinin) application, and cold treatments and their combinations in two faba bean genotypes. Acropetal node number of pod and seed set and pollen viability were recorded during the experiments. Application of BAP improved pollen germination. The application of 10–5 M BAP 4 days after flowering increased seed set at the lower nodes. Cold treatment (8/4°C day/night for 2 days) after the onset of flowering induced the formation of more pods and faster pod set compared to the non-cold treatment. The time to first seed was significantly reduced, and pollen viability was increased in plants exposed to cold treatment. Increased pollen viability also showed a significant positive correlation with seed setting. The combinations of 10–5 BAP and cold treatment together had similar and independent effects. These results will accelerate plant breeding in faba bean by providing additional tools for reducing generation time. 相似文献
29.
Edwige Gaby Nkouaya Mbanjo Fran?ois Tchoumbougnang Albert Sone Mouelle Julius Enyong Oben Moses Nyine Carine Dochez Morag Elizabeth Ferguson James Lorenzen 《Euphytica》2012,188(3):369-386
A well-saturated genetic linkage map is valuable for fundamental and applied genetic research. Genetic linkage maps of two half-sib diploid banana populations were constructed using allele-specific-polymerase chain reactions (AS-PCRs), diversity array technology (DArT), and simple sequence repeat (SSR) markers. Molecular maps were produced for each parent using the pseudo-testcross mapping strategy. The first maternal map (6142-1, 81 individuals) consisted of 231 markers divided as followed: 121 DArT, 106 SSR and 4 AS-PCR markers in 15 linkage groups (LGs) covering 670?cM. The second maternal map (6142-1-S, 58 individuals) contained a total of 152 markers including 71 DArTs, 79 SSRs, and 2 AS-PCRs mapped to 16 LGs that spanned 698?cM. The combined paternal map (139 individuals) comprised 316 markers (196 DArTs, 117 SSRs and 3 AS-PCRs) distributed over 15 LGs with a total map length of 1,004?cM. While distorted segregation of some markers was observed in all maps, this was much more frequent for the male parent. Homology between maps was assessed using common markers. While there was generally good congruity with regard to marker order across maps, incongruity in other cases may reflect chromosomal rearrangement events such as inversions, translocations, or deletions. The new banana map can provide a better understanding of the Musa genome and could be used for the identification of economically important traits and improvement of breeding strategies. 相似文献
30.
Juhasz Albert L. Smith Euan Smith Julie Naidu Ravendra 《Water, air, and soil pollution》2003,146(1-4):111-126
A bench scale, two-phase soil washing-biosorption process was developed for the remediation of p,p′-DDT-contaminated soil (containing 990 and 7750 mg kg-1 of p,p′-DDT). Removal of p,p′-DDT from contaminated soil was achieved by washing the soil with low molecular weight primary alcohols (ethanol or 1-propanol). An improved efficiency of p,p′-DDT removal was observed with increasing C-chain length of the cosolvent and by increasing the cosolvent volume fraction. When 40 or 80% 1-propanol were used, greater than 93% of p,p′-DDT was desorbed from the respective soils. p,p′-DDT was partitioned from the cosolvent solutions using biomass of Cladosporium sp. strain AJR318,501 as the sorptivematrix. When studies were conducted using a cosolvent-recycling regime (with 80% 1-propanol) greater than 95% of p,p′-DDT was removed from Soil A (990 mg kg-1 p,p′-DDT) and Soil B (7750 mg kg-1 p,p′-DDT) with the majority of the desorbed organochlorine repartitioning onto the fungal biomass. Less than 2.4 μg mL-1 p,p′-DDT was detected in the cosolvent wash solution of Soil A after 80 hr: potentially the cosolvent could be further reused to treat other soil. A higher concentration of p,p′-DDT was detected in the cosolvent wash solution of soil B after 120 hr (13.3 μg mL-1) indicating that the p,p′-DDT sorption sites on the fungal biomass were fully saturated. 相似文献