首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 312 毫秒
1.
E. Portis    L. Barchi    A. Acquadro    J. I. Macua  S. Lanteri 《Plant Breeding》2005,124(3):299-304
Cultivated cardoon (Cynara cardunculus L. var. altilis DC) belongs, together with globe artichoke (C. (cardunculus L. var. sylvestris L.) and wild cardoon (C. cardunculus L. var., sylvestris (Lamk) Fiori). to the family Asteraceae (Compositae). Cultivated cardoon is of regional importance in Italy. Spain and southern France, where it is used for the preparation of traditional dishes. It has been shown to have potential as a source of oil from its seeds, inulin from its roots and various biopharmaceuticals from its leaves. Levels of genetic diversity and relatedness between eleven Italian and 10 Spanish accessions were assessed by DNA profiling with eight AFLP primer combinations and at five microsatellite loci. The AFLP analysis of genetic similarities showed that the Spanish and Italian accessions represent two distinct gene pools; substantial variation was present within each accession. On the other hand a limited variation was detectable by applying SSR markers.  相似文献   

2.
Genetic diversity in 49 plants of 16 accessions representing one wild and two cultivated taxa of Cynara cardunculus L. (wild cardoon, cultivated cardoon and globe artichoke) was investigated using amplified fragment length polymorphic (AFLP) analysis. Four pairs of primers identified a total of 264 scorable loci, 196 of which were polymorphic. The number of markers scored per primer combination ranged from 41 to 107, with an average of 66 markers per primer combination. All the primer combinations detected polymorphism. The data were used for cluster analysis and AMOVA. The clusters obtained are in agreement with the current botanical classification and the differences among the taxa were substantial. The eco‐geographical groups within wild cardoon are clearly separated in relative subclusters, and reflect the geography of the collection areas. The six clones of the four cultivated artichoke varieties were clearly separated into four subclusters, corresponding to the current classification which is based on morphological traits. The results obtained may have a direct and important bearing on plant genetic resource conservation and management and on breeding.  相似文献   

3.
The genetics of resistance to Cucumber mosaic virus (CMV) in Cucumis sativus var. hardwickii R. Alef, the wild progenitor of cultivated cucumber was assessed by challenge inoculation and by natural infection of CMV. Among the 31 genotypes of C. sativus var. hardwickii collected from 21 locations in India the lowest mean percent disease intensity (PDI) was recorded in IC-277048 (6.33%) while the highest PDI was observed in IC-331631 (75.33%). All the four cultivated varieties (DC-1, DC-2, CHC-1 and CHC-2) showed very high PDI and susceptible disease reaction. Based on mean PDI, 8 genotypes were categorized as resistant, 13 as moderately resistant, 9 as moderately susceptible and one as susceptible. A chi-square test of frequency distribution based on mean PDI in F2 progenies of six resistant × susceptible crosses revealed monogenic recessive Mendelian ratio 1(R):3(S) to be the best fit. This monogenic recessive model was further confirmed by 1(R):1(S) ratio as the best fit for back cross with resistant parent and no fit for either 3:1 or 1:1 in the back cross with the susceptible parent. The results revealed that CMV resistance in C. sativus var. hardwickii was controlled by a single recessive gene. Considering the cross compatibility between C. sativus var. hardwickii and cultivated cucumber, the resistance trait can be easily transferred to cultivated species through simple backcross breeding.  相似文献   

4.
N. Senthil  T. Komatsuda 《Euphytica》2005,145(1-2):215-220
Brittle rachis of wild barley is controlled by two dominant complementary genes, Btr1 and Btr2, and mutation in either locus (btr1 or btr2) results in the non-brittle rachis of cultivated barley. In this study, a simple monogenic inheritance of non-brittle rachis was demonstrated, and moreover differentiation of multiple dominant alleles for either Btr1 or Btr2 among cultivated and wild barley lines was suggested. Two amplified-fragment-length polymorphism (AFLP) linkage maps of the genes were constructed using wild × btr1-type cultivar and wild × btr2-type cultivar F2 populations. The order of AFLPs and the btr1/btr2 locus was constant between the wild × cultivar maps and a cultivar × cultivar map previously constructed. No suppression of recombination due to the inter-subspecific crosses was noticed in the interval studied. The btr1 locus and all AFLP loci were separated in the wild × btr1-type cultivar F2 map, but the btr2 locus and eight AFLP loci did not recombine in the wild × btr2-type cultivar F2 map, thus slightly different levels of affinity between parental cultivars with the wild line was suggested at the btr1/btr2 locus.  相似文献   

5.
Phenoxy herbicides such as 2,4‐dichlorophenoxy acetic acid (2,4‐D) and 4‐chloro‐2‐methylphenoxy acetic acid (MCPA) are selective herbicides used extensively in agriculture for weed control. Wild radish (Raphanus raphanistrum) is a problem weed across the globe and heavily infests crop fields in Australia. Phenoxy herbicides are used to selectively control dicot weeds, including wild radish. As a result of selection, phenoxy‐resistant wild radish populations evolved in Western Australia. In this research, introgression of phenoxy resistance from wild radish to cultivated radish (Raphanus sativus) was investigated following classical breeding procedures. F1 progeny were generated by crossing MCPA‐resistant R. raphanistrum and MCPA‐susceptible R. sativus. F1 hybrids were screened for MCPA resistance. The MCPA‐resistant F1 hybrids were used to produce three generations of backcross progeny. Genetic analyses of F1 and backcross progeny demonstrated introgression of the MCPA‐resistant trait from wild radish to cultivated radish. Implications of phenoxy resistance introgression into cultivated radish include potential development of herbicide‐tolerant radish cultivars or other members of the Brassicaceae family.  相似文献   

6.
A tomato cultivar with high quality fruit and a long shelf life is a main goal in tomato breeding and it would be achieved using wild germplasm. The objective of this work was to explore the inheritance for fruit quality traits, especially fruit shelf life, in three tomato crosses using a standard Argentinean cultivar (Ca, cv ‘Caimanta’), a ripening mutant (nor, homozygous for the nor gene) of Solanum lycopersicum, and a wild cherry type (Ce, LA1385 of S. lycopersicum var. cerasiforme). The wild parent had a shorter fruit shelf life than the mutant genotype but higher than Ca. When the Ce genotype was analyzed in hybrid combination, the F1 (Ca×Ce) was similar to the wild genotype for shelf life whereas the F1 (nor × Ce) had a longer shelf life. Both F1 crosses and backcrosses to the cherry type genotype had significantly lower fruit weight than the cultivated genotypes but higher than the cherry type parent. In the F2 analysis, it was found that the inheritance underlying quality traits is complex since non allelic interactions were detected. A significant additive genetic variance was found for fruit shelf life as well as for other fruit quality traits in each cross. The genetic parameters analyzed by mean values and variances in parental, F1 and F2 and backcross generations indicated that the cross between the normal ripening cultivar and LA1385 of S. lycopersicum var. cerasiforme offers the best possibility to obtain long shelf life tomato genotypes with good fruit quality.  相似文献   

7.
In a backcrossing programme to transfer desirable characters from wild Avena maroccana Gdgr. to cultivated oats, A. sativa L., meiotically stable plants in BC1F3 and BC2F2 progenies were isolated. The recovery of stable genotypes with 2n = 6×= 42 chromosomes indicated that two backcrosses are enough for such a programme. The cytological observations in various backcross generations are presented and discussed.  相似文献   

8.
Fusarium root rot (FRR) is a major disease of common bean worldwide. Knowledge of the inheritance of resistance to FRR would be important in devising strategies to breed resistant varieties. Therefore, a 12 × 12 full diallel mating scheme with reciprocal crosses was performed to generate 132 F1 progenies, which were then advanced to the F3. The progenies were evaluated for resistance to FRR under green house conditions in Uganda. General combining ability (GCA) effects were highly significant (P ≤ 0.01) for disease scores. Specific combining ability effects were not significant (P > 0.05) in the F1, but were highly significant (P < 0.01) in the F3 generation. These results indicate that resistance to FRR was governed by genes with additive effects in combination with genes with non-additive effects. Reciprocal differences were also significant (P = 0.01) at F1 and F3, primarily reflecting a large influence of maternal effects in both these generations. In fact, susceptible parents did not differ significantly (P > 0.05) for disease scores when used as paternal parents in the F3, but differed strongly as maternal parents (P = 0.0002). Generally, the progenies were distinctly more resistant when the resistant parent was used as the female in crosses, especially as observed in the F3. The maternal effects were strong in the F3 generation, suggesting a complex form of cytoplasmic–genetic interaction. The non-maternal reciprocal effects in the F3 were significant (P < 0.05) in both the resistant × resistant diallel, and in the resistant × susceptible crosses. Mid-parent heterosis (MPH) occurred in most crosses, with average heterosis approximately equal in each of the three generations, indicating that epistasis was probably more influential than dominance of individual genes. Gene-number formulas indicated that several genes were involved in resistant × susceptible crosses. Among resistant × resistant crosses, many produced continuous distributions of F1 progeny scores, suggesting polygenic inheritance, while bi-modal distributions were characteristic of the F3 distributions, and fit expected ratios for two or three loci segregating in each cross. Dominant forms of epistasis favoring resistance were strongly indicated. Parent–offspring heritability estimates were moderate. Overall, the results indicate that resistant parents contain a number of different resistance genes that can be combined with the expectation of producing strong and durable resistance. The lines MLB-49-89A, MLB-48-89, RWR719 and Vuninkingi, with large and negative GCA effects, contributed high levels of resistance in crosses and would be recommended for use in breeding programs.  相似文献   

9.
Introgression of unadapted genes from the wild Cicer species could contribute to the widening of genetic base of important traits such as yield, yield attributes and resistance to major biotic and abiotic stresses. An attempt was made successfully to intercross two wild annual Cicer species with three cultivated chickpea cultivars. Four interspecific cross‐combinations were made, and their true hybridity was ascertained through morphological and molecular markers. These cross‐combinations were also studied for some important quantitative traits under real field conditions. The range, mean and coefficient of variation of agro‐morphological traits were assessed in the parental lines, their F1 and F2 generations to determine the extent of variability generated in cultivated chickpea varieties. A high level of heterosis was recorded for number of pods/plant and seed yield/plant in F1 generation. Three cross‐combinations of ‘Pusa 1103’ × ILWC 46, ‘Pusa 256’ × ILWC 46 and ‘Pusa 256’ × ILWC 239 exhibited substantially higher variability for important yield‐related traits. The present research findings indicate that these wild annual Cicer species can be easily exploited to broaden the genetic base of cultivated gene pool for improving seed yield as well as adaptation.  相似文献   

10.
Heterosis, or hybrid vigour, has been used to improve seed yield in several important crops for decades and it has potential applications in soybean. The discovery of over‐dominant quantitative trait loci (QTL) underlying yield‐related traits, such as seed weight, will facilitate hybrid soybean breeding via marker‐assisted selection. In this study, F2 and F2 : 3 populations derived from the crosses of ‘Jidou 12’ (Glycine max) × ‘ZYD2738’ (Glycine soja) and ‘Jidou 9’ (G. max) × ‘ZYD2738’ were used to identify over‐dominant QTL associated with seed weight. A total of seven QTL were identified. Among them, qSWT_13_1, mapped on chromosome 13 and linked with Satt114, showed an over‐dominant effect in two populations for two successive generations. This over‐dominant effect was further examined by six subpopulations derived from ‘Jidou12’ × ‘ZYD2738’. The seed weight for heterozygous individuals was 1.1‐ to 1.6‐fold higher than that of homozygous individuals among the six validation populations examined in different locations and years. Therefore, qSWT_13_1 may be a useful locus to improve the yield of hybrid soybean and to understand the molecular mechanism of heterosis in soybean.  相似文献   

11.
The male sterile plants that segregated in a BC5F2 of `C. sericeus × C. cajan var. TT-5' population were maintained by sib mating. The male sterile plants were crossed with ICPL-85012.Approximately 50% of the F1 plants were sterile. F2 plants derived from the fertile F1 plants did not segregate for male sterility. The reciprocal hybrid i.e. ICPL-85012 × Fertile derivatives from C. sericeus × TT-5, did not express male sterility. However, among the 12 F2 plant to row progenies, two segregated 25% male sterile plants and remaining 10 did not segregate. The segregation pattern in subsequent progenies revealed that the sterility was under control of a single recessive allele. Studies on the backcross and their BC1F2 and BC1F3progenies revealed another sterility gene which was found to be dominant in inheritance. This paper shows that what was thought to be cytoplasmic male sterility from C. sericeus cytoplasm is actually a single dominant gene possibly acting in concert with a single recessive gene to mimic cytoplasmic male sterility. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

12.
Summary Cajanus platycarpus, an incompatible wild species from the tertiary gene pool of pigeonpea (C. cajan (L.) Millspaugh), has many desirable characteristics for the improvement of cultivated varieties. To necessitate such transfers, embryo rescue techniques were used to obtain F1 hybrids. The F1 hybrids were treated with colchicine to obtain tetraploid hybrids, that were selfed to obtain F2, F3 and F4 progenies. All of the hybrids and subsequent progenies had an intermediate morphology between the two parents. Backcrossing of the tetraploid hybrids with cultivated pigeonpea was not possible given embryo abortion, with smaller aborted embryos than those obtained in the F0 parental cross.As a route of introgression, diploid F1 hybrids were backcrossed with cultivated pigeonpea and BC1 progeny obtained by in vitro culture of aborting embryos. BC2 plants were obtained by normal, mature seed germination. Although embryo rescue techniques had to be used to obtain F1 and BC1 plants, it was possible to produce BC2 and subsequent generations through direct mature seed. Every backcross to cultivated pigeonpea increased pollen fertility and the formation of mature seeds.Special project assistant till December, 2003.  相似文献   

13.
T. Tatlioglu 《Plant Breeding》1989,102(3):215-221
By genetic analysis of selfed progenies and reciprocal F1, F2 and B1: populations of crosses of a waxless mutant and three waxy plants two recessive genes were identified in kohlrabi (Brassica oleracea L. var. gongyloides), causing waxlessness independently from each other. Gene a is responsible for glossy waxless and gene b tor dull waxless plants. To be able to form a wax layer a plant must have both genes in the dominant constitution, i.e. A.B. (“complementary gene effect). Some segregation results which deviate from expectation could indicate a potential linkage between one of the two wax loci and the incompatibility locus. Both genes can be used as markers m hybrid breeding of cole crops as well as in basic research.  相似文献   

14.
Asian soybean rust (ASR) caused by Phakopsora pachyrhizi severely reduces seed yield in soybean. Molecular tagging of ASR resistance can help in the process of resistance breeding. In this study, an F2 population of cross (susceptible cultivar ‘NRC 7’ × resistant exotic genotype EC 241780) was used for bulked segregant analysis (BSA) with 25 SSR (simple sequence repeat) primers linked with six Rpp genes. Among them, five polymorphic SSR markers, viz., Sct 187, SSR 1859, Satt 191 (Rpp1b like loci) and Satt 215, Sat_361 (Rpp2 loci) distinguished the ASR resistant and susceptible bulks and individuals. In combined marker analysis, the markers Satt 191 (Rpp1b like loci) and Satt 215 (Rpp2 loci) were linked with ASR severity score and were also confirmed in individual 110 F2 segregants. Hence, these markers could be utilized in the marker assisted rust resistance breeding of Rpp1b like and Rpp2 genes. In silico candidate gene analysis for hypersensitive response revealed that Satt 191 linked region was rich in genes encoding apoptotic ATPase having leucine‐rich repeat (LRR) domain.  相似文献   

15.
Modern rice varieties that ushered in the green revolution brought about dramatic increase in rice production worldwide but at the cost of genetic diversity at the farmers’ fields. The wild species germplasm can be used for broadening the genetic base and improving productivity. Mining of alleles at productivity QTL from related wild species under simultaneous backcrossing and evaluation, accompanied by molecular marker analysis has emerged as an effective plant breeding strategy for utilization of wild species germplasm. In the present study, a limited backcross strategy was used to introgress QTL associated with yield and yield components from Oryza rufipogon (acc. IRGC 105491) to cultivated rice, O. sativa cv IR64. A set of 12 BC2F6 progenies, selected from among more than 100 BC2F5 progenies were evaluated for yield and yield components. For plant height, days to 50% flowering and tillers/plant, the introgression lines did not show any significant change compared to the recurrent parent IR64. For yield, 9 of the 12 introgression lines showed significantly higher yield (19–38%) than the recurrent parent IR64. Four of these lines originating from a common lineage showed higher yield due to increase in grain weight and another three also from a common lineage showed yield increase due to increase in grain number per panicle. For analyzing the introgression at molecular level all the 12 lines were analyzed for 259 polymorphic SSR markers. Of the total 259 SSR markers analyzed, only 18 (7.0%) showed introgression from O. rufipogon for chromosomes 1, 2, 3, 5, 6 and 11. Graphical genotypes have been prepared for each line and association between the introgression regions and the traits that increased yield is reported. Based on marker trait association it appears that some of the QTL are stable across the environments and genetic backgrounds and can be exploited universally.  相似文献   

16.
Wild Lens taxa are invaluable sources of useful traits for broadening genetic base of cultivated lentil. Nine inter‐sub‐specific and interspecific crosses were made successfully between cultivated (Lens culinaris ssp. culinaris) and wild lentils (L. culinaris ssp. orientalis, odemensis, lamottei and ervoides). The effect of species groups, day length and temperature on crossability in lentils was evident under normal winter sowing in New Delhi and in summer Himalayan nursery at Sangla in Himachal Pradesh, India, although pollen fertility assessed in all the cross‐combinations showed no significant variation. True hybridity of nine inter‐sub‐specific and interspecific crosses was confirmed through morphological and molecular (ISSR) markers, in which three of 120 primers could confirm the hybridity of all the crosses. All cross‐combinations were also studied for important quantitative traits related to yield. The range, mean and coefficient of variation were estimated in parental lines, F1 and F2 generations to determine the extent of variability generated in cultivated lentils through the introgression of genes from wild L. taxa. A high level of heterosis was observed in F1 crosses for important traits studied. Substantially higher variations for seed yield and its attributing traits were exhibited in F2 generations indicating transgressive segregation. The results of the present investigation revealed that wild L. taxa can be successfully exploited for lentil improvement programmes, and the variations generated could be easily utilized for broadening the genetic base of cultivated lentil gene pool for improving the yield as well as wider adaptation.  相似文献   

17.
Summary Seedlings of date palm (Phoenix dactylifera L.), obtained from seven cultivars crossed with two males, were analyzed by polyacrylamide gel electrophoresis for esterase (EST), glutamate oxaloacetate transaminase (GOT), endopeptidase (ENP) and alcohol dehydrogenase (ADH) polymorphisms. Eleven, eight, five and two phenotypes were revealed for the enzymes tested, respectively. Seedlings of F1 populations derived from Bayoud (Fusarium)-resistant and low fruit quality cultivars were characterized by a high electrophoretic polymorphism, when compared with progenies of Bayoud-susceptible and high fruit quality cultivars. In almost all cases, the most frequent electrophoretic phenotypes scored for each enzyme in different F1 populations, were similar to those of the corresponding parent cultivars. Heterozygous phenotypes have been found for, at least, 3 loci; Got-2, Est-1 and Enp, indicating that such loci could be used to screen for hybrid seedlings. The expected Mendelian segregation of allozymes has been observed for these 3 loci, in many F1 populations. It seems that progenies of Bayoud-resistant cultivars are characterized by a high level of electrophoretic polymorphism. The estimation of this index and the search for genetic linkage with segregating allozymes, may be biochemical criteria useful as an aid in distinguishing date palm seedling populations derived from Bayoud-resistant cultivars and suitable for breeding programs.  相似文献   

18.
The present study evaluated the individual plants reaction of F2 hybrid generation of C. annuum: ATZ1 × PO and ATZ1 × CDT as well as two interspecific hybrids: C. frutescens × C. annuum ATM1 and C. frutescens × C. chinense on androgenesis conditions in in vitro anther cultures. The experiment was carried out following a modified method of Dumas de Vaulx et al. (Agronomie 1:859–864, 1981). There were demonstrated clear differences in the effectiveness of androgenesis both between the pepper hybrid forms as well as among individual plants of all the genotypes tested. The highest effectiveness of androgenic embryos development was observed for the cultivated form of C. annuum: (ATZ1 × PO)F2. Anthers of most of the plants of this hybrid produced embryos at the level higher than 5%, while in anther cultures of the second C. annuum hybrid (ATZ1 × CDT)F2 almost 3-fold fewer embryos and plants were produced. Anthers isolated from flower buds of interspecific hybrids formed much lower number of embryos. A positive reaction was recorded for five hybrid plants of (C. frutescens × C. annuum ATM1)F2, while in case of (C. frutescens × C. chinense)F2 androgenic embryos were obtained from anthers of two plants. Only in the case of a one of these plants did the effectiveness of androgenesis exceed 5%. The ploidy level of the regenerants was determined by flow cytometry. Among the regenerants there were observed both haploid forms and the plants with the diploid number of chromosomes.  相似文献   

19.
A self-incompatible (SI) line, S-1300, and its maintainer 97-wen135, a self-compatible (SC) line, were used to study the inheritance of maintenance for self-incompatibility in B. napus. The ratio of SI plants to SC plants from S-1300 × 97-wen135 F2 and (S-1300 × 97-wen135) × 97-wen135 was 346:260 and 249:232, fitting the expected ratio of 9:7 and 1:1, respectively. Based on these observations, here we propose a genetic model in which two independent loci, S locus and S suppressor locus (sp), are predicted to control the inheritance of maintenance for self-incompatibility in B. napus. The genotypes of S-1300 and 97-wen135 are S 1300 S 1300 sp 1300 sp 1300 and S 135 S 135 sp 135 sp 135 , respectively. S 135 is dominant to S 1300 , but coexistence of sp 1300 and sp 135 fails to suppress S locus. Both S 1300 and S 135 can be suppressed by sp 135 , while sp 1300 can suppress S 135 but not S 1300 . The model contains two characteristics: that a dominant S locus exists in self-compatible B. napus, and that co-suppression will occur when sp loci are heterozygous. The model has been validated by the segregation of S phenotypes in the (S-1300 × 97-wen135) × S-1300, the progenies of SC S-1300 × 97-wen135 F2 plants and DH population developed from S-1300 × 97-wen135 F1. This is the first study to report co-suppression of S suppressor loci in B. napus. The genetic model will be very useful for developing molecular markers linked to maintenance for self-incompatibility and for dissecting the mechanism of SI/SC in B. napus.  相似文献   

20.
Controlled crosses in bambara groundnut were attempted between a range of thirty-six bambara groundnut landraces (thirty domesticated (V. subterranea var. subterranea) and six wild (V. subterranea var. spontanea)). Ten F1 seed were produced. Of these, eight germinated producing F2 populations. On seed set, four populations could be unambiguously confirmed as true crosses by F3 seed coat colour. A single F2 population, derived from a domesticated landrace from Botswana (DipC; female parent) crossed with a wild accession collected in Cameroon (VSSP11; male parent) was used to study a range of agronomic and domestication traits. These included; days to emergence, days to flowering, internode (fourth) length at harvest, number of stems per plant, leaf area, Specific Leaf Area (SLA), Carbon Isotope Discrimination (CID), 100 seed weight, testa colour and eye pattern around the hilum. On the basis of variation for internode length and stems per plant, 14 small F3 families were selected and grown under field conditions to further investigate the genetic basis of the ‘spreading’ versus ‘bunched’ plant character, a major difference between wild and cultivated bambara groundnut. Results presented suggest that traits including leaf area, SLA, CID and 100 seed weight are controlled by several genes. In contrast, the variation for traits such as internode length, stems per plant, days to emergence and seed eye pattern around the hilum are likely to be under largely monogenic control. The results of this work are discussed in relation to the domestication of bambara groundnut.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号