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1.
In vivo interspecific pollinations were performed and immature seed development investigated by histological methods in order to study crossability barrier(s) in Cicer L. species wide hybridization. Seven of the eight wild annual Cicer species, belonging to the secondary and tertiary gene pools, were used in reciprocal crosses with the cultivated chickpea. It was confirmed that the zygote was formed in all interspecific crosses. The embryos showed continued and retarded growth at different rate in various crosses, but eventually aborted at an early pro-embryo stage in all crosses except C. arietinum L. ×C. echinospermum Dav. Reciprocal cross differences were observed in early embryo growth rate and could have implications in obtaining hybrids. This study further emphasizes the necessity for developing appropriate and efficient in vitro procedures for rescuing immature globular hybrid pro-embryos, which will make the wild Cicer gene resources amenable to chickpea improvement.  相似文献   

2.
This work presents the results of studying (1990–1992) such wild oat species as Avena clauda Dur., A. pilosa M.B., A. bruhnsiana Grun., A. wiestii Steud., A. barbata Pott.; weedy species – A. sterilis L., A. fatua L. and A. ludoviciana Dur. The range of variability by agricultural traits has been shown and plant forms have been identified by such traits as earliness, dwarfness, productive tillering, resistance to lodging, crown and stem rusts, powdery mildew, tolerance to BYDV and other morphological characters. The author has defined parameters of interrelation between the duration of the vegetation period and its separate phases as well as between other agricultural and morphological traits.  相似文献   

3.
To study the relationships and genetic diversity among wild hops, Humulus lupulus, we analyzed 133 samples of wild hops collected from Europe, Asia and North America using polymorphism on 11 microsatellite loci. Although only three primers showed bands in Japanese hops, all other samples showed polymorphic bands at most loci. There were no duplicate genotypes among samples of European, Chinese and North American hops, and each individual hop could be distinguished completely. The phylogenetic tree constructed from DA distance with the UPGMA method showed a large cluster comprised of European hops, although Russian hops from the Caucasus and Altai regions were separate from the European cluster. Chinese and North American samples gave distinct clusters suggesting genetic differentiation. This study has indicated that hop microsatellite DNA is differentiated, and is dependent upon the origin in regions of Europe, Asia and North America.  相似文献   

4.
Nineteen natural populations of Fagopyrum homotropicum, a self-fertilizing close relative of common buckwheat, from the Yunnan and Sichuan provinces of China were investigated for their chromosome number and allozyme variation at 16 loci of 11 enzymes. Three populations, 'Deqin', 'Zhongdian', and 'Xiancheng', were revealed to be allotetraploid. Judging from allozyme constitution of the tetraploid and their possible progenitors, diploid progenitors are probably the diploid population of F. homotropicum from Lijiang and a natural population of F. esculentum ssp. ancestralis. Diploid populations of F. homotropicum are fixed for a given allele at almost all isozyme loci. Allozyme variation has been maintained in natural populations mainly by fixing different alleles in different populations, as they are highly differentiated among the populations (Gst = 0.969). The position of populations in the phylogenetic tree constructed from genetic distance nearly corresponded with the geographical position of the populations.  相似文献   

5.
A wild onion species from Karaj valley east of Tehran istaxonomically described as Allium asarense R. M.Fritsch et Matin. Sharing the bubble-like inflated lower scapewith A. vavilovii, the newspecies differs by semi-cylindrical leaves and small flowerswith translucent greenish-yellow tepals from all other knownspecies of Allium sect.Cepa. Molecular data suggest a closerelationship to A. cepa(but to a lesser degree than A.vavilovii) and indicate a still weakerphylogenetic connection of A.oschaninii to the common onion. The questionabout the possible wild ancestor of A.cepa is discussed against this background, and akey for determination of the Oschaninii-alliance of sect.Cepa is presented.  相似文献   

6.
The goal of this paper is to evaluate the relative efficiency of two strategies that favour dung beetles conservation (Scarabaeinae, Aphodiinae, Geotrupinae) in Southern Europe: extensive grazing and wild ungulate management. We conducted a study in the French Cévennes national park/UNESCO World Biosphere Reserve where dung beetles are distributed in a dichotomous sheep (grasslands, shrublands) and deer (clearings, shrublands, forests) droppings dominating abroad landscape. Natural sheep droppings and deer lumps dung beetle assemblages have been sampled two consecutive years during spring, summer and autumn in five representative habitats. This sampling of natural assemblages allowed for the estimation of (i) the density of trophic resource in the habitats, (ii) the regional dung beetle fauna and the distribution of species among the habitats and (iii) the density of beetles in natural droppings and the evenness of assemblages. High diversity, high species density in droppings and high evenness were observed in grazed shrubland, whereas fewer species were observed in deer lumps. Our results clearly showed that, while wild ungulates manure is not enough to ensure the conservation of the regional dung beetle species pool, the spatial habitat heterogeneity of grazed shrubland allows the local coexistence of numerous species. Consequently, one may expect that the conservation of European dung beetle fauna, especially Scarabaeinae and several long lifetime species, could be enhanced by extensive grazing.  相似文献   

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