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991.
Resistance to viruses such as wheat streak mosaic virus (WSMV) and barley yellow dwarf virus(BYDV) is lacking in the primary gene pool of wheat, and therefore resistance is being introgressed from wild relatives such as Thinopyrum species. Resistance to BYDV was found in partial amphiploids (2n = 8x = 56, consisting of 42 wheat and14 alien chromosomes) obtained in hybrids between wheat and both Th. intermedium and Th.ponticum. GISH analysis revealed that the alien genomes of all but one resistant partial amphiploid were heterogeneous consisting of different ratios of St, Js and J genome chromosomes obtained from theThinopyrum parent. Translocated chromosomes consisting of Robertsonian, interstitial and terminal translocations between the different genomes were also detected. The tissue blot immunoassay showed that partial amphiploids having resistance could be inoculated with the virus but both virus multiplication and spread were completely blocked. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
992.
The reported content of flavonoids in the needles of Norway spruce, Picea abies, has been used as a basis for a directed search for compounds previously undetected in this species. Combined with advanced chromatographic methods and sensitive detection techniques, the directed search approach assisted in the identification of the novel flavonols, myricetin 3- O- (6-acetylglucoside) and syringetin 7- O-glucoside, and several other flavonoids isolated for the first time from this species.  相似文献   
993.
George  R. A. T.  Evans  D. R. 《Euphytica》1981,30(2):483-492
Summary Fifty-five radish selections, comprising 39 named cultivars, were grown for classification based on morphological characteristics. The major characters used were the ratio of length to width of the hypocotyl, and the colour of the hypocotyl. Cultivars were further subdivided by the length of the longest leaf and the number of fully expanded leaves at harvest. The coefficient of variation is given for each cultivar. The classification identifies a total of 25 classes based on combinations of root shape and colour. These classes can then each be subdivided 25 times based on combinations of leaf length and leaf number.  相似文献   
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The unit chain compositions of debranched foxtail, proso, pearl, and finger millet amylopectins and their ϕ,β‐limit dextrins were analyzed by high‐performance anion‐exchange chromatography. The ϕ,β‐limit dextrins reflected amylopectin internal chain profiles. The amylopectins had average chain lengths ranging from 17.94 to 18.12. The ranges of external chain length, internal chain length, and total internal chain length of the millet amylopectins were 11.85–12.33, 4.75–5.09, and 11.64–12.28, respectively. The relative molar concentration of B‐chains in the amylopectins was close to 50% in all samples. Significant differences were, however, observed in the proportions of very short “fingerprint” B‐chains (Bfp, degree of polymerization 3–7) and the major group of short B‐chains (BSmajor): foxtail and proso millets possessed high amounts of Bfp‐chains, whereas finger and pearl millets had higher amounts of BSmajor‐chains, suggesting possible differences in the fine structure of the clusters and building blocks of the amylopectins. Millet amylopectin can be classified structurally as type 2.  相似文献   
996.
Tropical Animal Health and Production - The increase in haylage production leads to the search for additives that improve its fermentation and nutritional value. This study aimed to assess the...  相似文献   
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Cocoa is a major crop and income source for most farmers and rural households in the Centre, South and South-West regions of Cameroon, where cocoa is generally produced in agroforestry systems. In this country, cocoa-based agroforestry systems (CBAFS) are undergoing multiple changes alongside the rapid changes underway in the natural, economic and socio-political conditions. This study—carried out in the Akongo subregion in central Cameroon—was designed to gain insight into the CBAFS trends and dynamics in the light of those multiple changes. This semi-structured socioeconomic survey involved interviews and direct observations at plot, farm, household and village scales. Overall, forty cocoa growers from ten villages were interviewed and then fifteen cocoa plots were characterized on the basis of the survey findings. They revealed that cocoa was the major crop in this study area, with cocoa plantations occupying three quarters of the total farming area. Three types of CBAFS were identified, which differed according to their vegetation structure, management practices and age of the plantations. Dynamics affecting the structural characteristics and the spatial extension of these systems emerged and were intimately linked to the dynamics of the cocoa farmer population in relation to their context.

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1000.
Agroforestry Systems - In temperate regions, tree leaves could be a source of energy, protein, vitamins and minerals for ruminants. Our objective was to study the diversity in chemical composition...  相似文献   
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