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1.
Summary The fatty acid composition of seed-oil of breeding lines and F1 hybrids of Matthiola incana was analyzed, using direct esterification and gas chromatography. The breeding lines tested differed significantly with respect to the levels of palmitic, oleic, linoleic and linolenic acids. Embryonic-stage heterosis in linolenic acid concentration was demonstrated by F1 hybrid seeds, derived from mating horticulturally different lines of M. incana. Linolenic acid content was negatively correlated with both oleic acid content (r=–0.85) and linoleic acid content (r=–0.66). None of the breeding lines or the F1 hybrids significantly passed the limit of 67% linolenic acid. Possible genetic and biochemical explanations for the above phenotypic data are discussed. 相似文献
2.
Three diploid perennial sunflower species are useful for variety improvement: Helianthus mollis, because of sessile leaves, H. salicifolius, because of a high oil concentration, and H. maximiliani, a potential source of resistance to Sclerotinia sclerotiorum. The crossability of these species to cultivated sunflower was examined.Hybrids were obtained from eight combinations, with 3–15 F1 plants per combination. The F1's exhibited the dominant phenotype of the wild species. Pollen viability varied between 32.1 and 69.9%. Meiosis was irregular in the F1 hybrids. At diakinesis, bivalents (62.7–97.9% of meiocytes), univalents (0–31.23%), and multivalents (3.84–7.68%) were detected. At anaphase I, chromosome bridges were detected in 6.77 to 11.44% of meiocytes. Fast chromosomes in metaphase I, and lagging chromosomes in anaphase I and telophase II were evidenced in a high percentage of meiocytes. 相似文献
3.
Interspecific F1 hybrids were produced after artificial intercrossing of six Sideritis species indigenous to Greece, namely: S. athoa, S. euboea, S. syriaca, S. raeseri, S. scardica, S. clandestina and a cultivated clone of S. raeseri. It was found that all species cross with each other, but the level of crossability varied with the cross-combination. In the yield evaluation experiments, the interspecific hybrids with a common female parent were considered as a group. It was observed that yield during the year of establishment was relatively low, but the interspecific hybrids out-yielded the control in both fresh and dry weight. All hybrids produced higher yields in the following years and their productivity started to decline after the fifth year. All hybrids produced higher yields than the control in all six years of the experiment. The highest yield over the years, in fresh and dry weight, was produced by the group Sideritis raeseri cultivated clone (cc) ×Sideritis spp. This yield, however, was not always significantly different from the yield produced by the second in the rank group (S. clandestina×Sideritis spp.). A high correlation (r > 0.99) between fresh and dry weight was observed. The two groups with the highest yield also had the highest essential oil content. In addition, all the interspecific hybrids had a higher essential oil content than the control species. Furthermore, the essential oil content of the selected individual hybrid plants ranged between the midparental value to a value higher than the high-parental species, indicating an additive and dominance gene action. It was also found that the content of the essential oil in the seven most important components (pinene, lemonene, cynene, menthone, copaene, caryophyllene and valerianic ester) varied from hybrid to hybrid. Given that Sideritis reproduces mainly asexually, the direct use of individual interspecific hybrids with higher yield and content in essential oil than the control species is possible in cultivation. 相似文献
4.
Summary By crossing amphimictic P. longifolia and apomictic P. pratensis fertile hybrids were obtained. In F2 populations a vast range of types was observed. New combinations were found, which is shown by data on plant length and hairiness of the lemma. Crossing F1 hybrids with P. pratensis gave more P. pratensis-like plants. Data on seed yield, uniformity and turf performance in later generations are given. The implications for breeding are discussed and it is concluded that interspecific crosses can be used for introducing a sexual phase in P. pratensis breeding. Non-hairiness of the lemma can be incorporated. 相似文献
5.
Summary F5 seeds from six highly heterotic F1 hybrids were produced to determine whether the superior performance of F1 hyrids could be fixed in pure-line derivatives of pea (Pisum sativum L.). For each cross, 24–31 F5 lines derived from single seed descent were compared with F1 hybrids and their parents in two environments. The F1 hybrids out-yielded the best parent by up to 11%. All crosses produced F5 lines which were as high in yield as the F1 hybrids indicating that pure-line derivatives equivalent in yield to the heterotic F1 hybrid could be developed by conventional breeding. Heterosis of the F1 hybrids over the best commercial cultivar was thus a useful indicator of the future performance of the pure-line derivatives. These results indicate that overdominance was not an important component of heterosis in peas. 相似文献
6.
Summary Five parents from each of four race groups of common bean (Phaseolus vulgaris L.) were hybridized to produce five crosses within each group. Also, five crosses were made for each of the six possible combinations among four groups. Parents, F1 and F2, and parents, F2 and F3 were evaluated for seed yield in 1990 and 1991, respecitively, at two locations in Colombia.Yield of parents belonging to Middle American races and crosses among them was higher than that of races of Andean origin. Positive correlations were found among the mid-parent value, F1, F2 and F3. Also, the mid-parent value predicted the mean seed yield of all possible lines that could be derived from the F-generation in 42 out of 47 crosses. Four crosses, all between common bean races of Andean and Middle American origin, indicated a possible loss of favorable epistatic parental alleles. On average, mean yield of interracial F1 hybrids was higher than that of intraracial ones.Positive heteroris (26.4%–123.8%) over the mid-parent in 31 crosses, and F1s yielding higher (23.7%–91.8%) than the high parent in 20 crosses and yielding higher (22.1%–53.2%) than the highest control among all parents (MAM 13) in 12 crosses, were found. Heritability, estimated by the parent-offspring regression, ranged from 0.42± 0.07 to 0.49±0.04. Expected and realized gains from selection (at 20% selection pressure) ranged from 10.3% to 21.0% over the mean of F1 hybrids and F2 and F3 population bulks. 相似文献
7.
Summary Meiosis was studied in some triploid, tetraploid and hexaploid F1-hybrids from Solanum acaule x S. bulbocastanum and in a triploid F1-hybrid from S. acaule x S. tuberosum-haploid.The only anomaly found was stickiness at metaphase I, the degree of which appeared to be related to the proportion of the S. bulbocastanum chromosomes in the hybrids. No stickiness occurred at pre- and post-metaphase stages.A clear allosyndetic pairing between chromosomes of the two S. acaule genomes was observed in all triploid and tetraploid hybrids. These genomes apparently are closely related and little differentiated. The triploids S. acaule x S. bulbocastanum had 0–1 trivalent per cell, whereas 2–5 trivalents per cell were observed in the triploid S. acaule x S. tuberosum-haploid. Therefore S. acaule is more closely related to S. tuberosum L. than to S. bulbocastanum. A small amount of pairing between S. acaule and S. bulbocastanum is apparent from the occurrence of multivalents in all hybrids.Hexaploid F1's (2n=72) showed a nearly complete homologous pairing of chromosomes (35.2 bivalents per cell) and generally a normal separation of chromosomes at anaphase: 36-36. This offers an explanation for their high fertility. Triploid F1's from S. acaule x S. bulbocastanum have a high frequency of univalents leading to irregular separation of chromosomes at anaphase and consequently to unbalanced gametes and extreme sterility. In the tetraploid F1's (2n=48) nearly complete bivalent pairing was observed, 50% expectedly being homologous and 50% homoeologous pairing. Separation of chromosomes at anaphase was generally normal 24-24. In spite of this normal behaviour and allowing for tight stickiness at metaphase the tetraploids are very sterile. A satisfactory explanation cannot yet be given.Selfing and intercrossing hexaploid F1's gives normal berry set and many seeds per berry. However crosses with S. tuberosum and even those with the fertile hexaploid hybrid from 8x-S. acaule x 4x-S. tuberosum are little successful: berry set is far below normal and the berries are either parthenocarpic or contain only one or two seeds. These rather unexpected results warrant further investigation. Large-scale selfings and intercrosses of triploid and tetraploid hybrids have not been successful as yet. Among the female gametes of tetraploid hybrids a few appeared to be functional in crosses with hexaploid hybrids and in those with S. bulbocastanum. 相似文献
8.
Cytoplasmic male sterility (CMS) system based on the cytoplasm from Moricandia arvensis (mori) was investigated for fertility restoration and agronomic potential. Fertility restorer gene for mori CMS was introgressed from cytoplasm donor species as all the evaluated Brassica juncea genotypes (155) acted as sterility maintainers. The allosyndetic pairing between Ma and the A/B genome chromosomes in the monosomic addition plants (2n= 18II + 1Ma) facilitated the gene introgression. Partial fertility restoration (43–52% pollen grain stainability) in F1 hybrids and absence of segregation for male sterility in F2 progenies suggested gametophytic control of fertility restoration. The pollen fertility in the F1 hybrids was, however, sufficient to ensure complete seed set upon bag selfing. Introgression from M. arvensis also helped in correction of chlorosis associated with mori cytoplasm in CMS and fertile alloplasmic B. juncea plants. Yield evaluation of thirty F1 hybrids having the same nuclear genotype but varied male sterilizing cytoplasms (mori, oxy, lyr, refined ogu), in comparison to respective euplasmic hand bred control hybrids, allowed an estimate of yield penalty associated with different CMS systems. It ranged from 1.8% to 61.6%. Hybrids based on cytoplasmically refined ogu were most productive followed by those based on cytoplasmically refined mori CMS. The male sterility systems emanating from somatic hybridization were found superior than those developed from sexual hybridization. 相似文献
9.
Summary Three non-tuberous Solanum species of series Etuberosa-S. brevidens (brd), S. etuberosum (etb) and S. fernandezianum (frn)-upon selfing displayed compatible berry set but seed set varied and on an average was below normal. Also in crosses between species berry set was unhampered (apart from the crosses with short-styled frn as pollen plant), but the interspecific hybrid plants showed various degrees of sterility and a low average seed set upon selfing. Cytological investigations revealed that in pure species-plants semi-sterility regularly occurred and was invariably associated with multivalent associations (up to decavalents). This may account for the decreased seed set found after selfing and intercrossing. Meiosis in F1-hybrids was even more irregular, 75% of the pmc's showing multivalents involving from 4 to as many as 22 chromosomes in various complicated configurations in which even numbers of chromosomes were predominant. However, anaphase I separation was numerically balanced in more than 75% of the cells. Pollen stainability was very low in the hybrids.It is concluded that heterozygous translocations occur within each species and that the genomes of the species are differentiated by means of gross structural changes. In view of this and of the high chromosome pairing affinity the genome symbols E
1, E
2 and E
3 are proposed for etb, brd and frn, respectively.Crossability of the Etuberosa species with tuberous S. pinnatisectum (pnt) was slightly more successful (average 2.7 seeds/berry) than that of Etuberosa species hybrids with S. pinnatisectum (average 1.7 seed/berry). In the hybrids studied-etb × pnt, frn × pnt and (brd × etb) × pnt-a high frequency of univalents was the rule (range 6–16 per cell). In addition rod bivalents (4–8 per cell) and a low frequency of trivalents occurred (0–3 in the biparental hybrids and 1–4 in the trispecific hybrid).Utilization of the valuable characters of Etuberosa for potato breeding is dependent on the degree of gene exchange between Etuberosa chromosomes and chromosomes of tuberous species. In the diploid hybrids such exchange, though limited, may take place through bivalents and trivalents. As shown in this article such diploid hybrids are non-crossable because of complete male and female sterility. Only after doubling the number of chromosomes the hybrids are fertile and can be used for further crosses. 相似文献
10.
Summary Interspecific hybridization between Brassica napus L. (2n=38, a1a1c1c1) and B. oleracea var. capitata L. (2x- and 4x-cabbage; 2n=2x=18, cc and 2n=4x=36, cccc) was carried out for the purpose of transferring clubroot disease resistance from the amphidiploid species to cabbage. Nineteen hybrids with three different chromosome levels (2n=28, a1c1c; 2n=37, a1c1cc and 2n=55, a1c1cccc) were obtained. The F1 plants were mostly intermediate between the two parents but as the number of c genomes in the hybrids increased, the more closely the hybrids resembled the cabbage parent. All F1 hybrids were resistant when tested against race 2 of Plasmodiophora brassicae
wor. The complete dominance of resistance over susceptibility suggested that the gene(s) controlling resistance to this particular race of the clubroot pathogen is probably located on a chromosome of the a genome in Brassica.Contribution No. J654. 相似文献
11.
J. G. Th. Hermsen 《Euphytica》1963,12(1):1-16
Hybrid necrosis is the premature gradual death of leaves and leaf sheaths in certain wheat hybrids. It is based on two complementary genes Ne
1 and Ne
2. Hitherto 89 Ne
1-carriers and 207 Ne
2-carriers from many countries are known (table 1 and 2). This corresponds with more than 18,000 different necrotic cross combinations.The degree of necrosis in the F1's varies greatly, due to multiple allelism of Ne
1 and Ne
2. Nine necrosis grades are described in table 3. Grades 6–8 are called severe necrosis (no seed is produced), 3–6 moderate necrosis (premature seed), 0–3 weak necrosis (normal seed). Most severely necrotic F1's could be brought to seed production by raising them under extra favourable conditions in a small growth-chamber. Growing moderately necrotic F1's in pots outside, at a high fertility level of the soil, resulted in a striking increase of the seed production.On the basis of the above mentioned data and results some practical advice is given to the breeders about the handling of necrotic crosses. In addition some ways to preclude hybrid necrosis are indicated, though the wheat breeder is advised against a systematic avoiding of necrosis because many combinations of excellent varieties then remain untried. 相似文献
12.
Summary Interspecific hybrids have been obtained in an otherwise incompatible cross betweenBrassica juncea × Brassica hirta through the in vitro culture of hybrid ovules and ovaries. The best response was observed from ovules and ovaries cultured 10–15 and 5–7 days after pollination respectively on a basal medium supplemented with indoleacetic acid, kinetin and casein hydrolysate. In some cases the basal cut end of the ovaries proliferated to form callus and shoots. The in vitro-derived hybrid seeds varied in their colour, size and shape, and the F1 plants in the field showed a large diversity in their morphological traits. The hybrids were sterile, and had an intermediate number of chromosomes (2n=30). 相似文献
13.
Summary Crosses between a wild species C. chacoense and three cultivated species of chili pepper viz. C. annuum, C. frutescens and C. chinense yielded hybrids when C. chacoense was the seed parent but the reciprocal crosses were unsuccessful. C. chacoense × C. annuum F1 hybrids were partly fertile and therefore an F2 population could be raised; the other two F1 hybrids were totally sterile. Chromosome pairing in the F1 plants resulted largely in bivalents and a few multivalents and univalents. The genomes of the four species share large homologies and the role of chromosome structural changes in genome differentiation is suggested. Hybrid sterility is the major reproductive isolation mechanism. 相似文献
14.
J. J. Hardon 《Euphytica》1969,18(3):380-388
Summary Yield and morphology of F1 hybrids E. guineensis x E. oleifera are discussed. Yield of the hybrids in terms of total fruit weight is promising but the oil content of the mesocarp is intermediate between the parental species and lower than in E. guineensis.
E. oleifera has a marked tendency towards the production of parthenocarpic fruits. This character is fully dominant in the hybrid. Because of this the percentage fruit per bunch in the hybrids therefore tends to become higher than in E. guineensis partly offsetting the lower percentage oil on mesocarp.The oil composition of the parental species and hybrids are compared.Height increment of the hybrids is substantially lower than of E. guineensis but annual frond production is approximately the same. There is some hybrid vigour for frond area. For most morphological, vegetative and reproductive characteristics E. oleifera exhibits complete dominance over E. guineensis. 相似文献
15.
Creeping bentgrass (Agrostis
stolonifera L. or A. palustris Huds.) is a highly outcrossing allotetraploid species. It can form hybrids with a number of other Agrostis species and Polypogon genus. However, cytology and pollen grain fertility of the creeping bentgrass interspecific and intergeneric hybrids are
not well known. In this research, chromosome pairing behaviors during meiosis I in F1 and pollen viability of F1 hybrids, as well as seed set rate and seed germination rate of backcrosses were studied in hybrids between creeping bentgrass,
and other bentgrass species and three species of Polypogon genus. Abnormal chromosome pairing, laggard chromosomes, and premature segregation in F1 hybrids were found. Pollen viability ranged from 1.6 to 48.5% amongst F1 hybrids, significantly lower than that of the parents (85.5–94.1%). Some hybrids produced pollens of different sizes within
the same anther. Seed set following backcrosses using F1 hybrids as the male parent and creeping bentgrass as the recurrent parent was significantly lower than their parents. The
study of chromosome paring behaviors and progeny fecundity are important in utilizing the alien genes to improve bio-stress
and abio-stress resistance, and in assessing the potential transgene risks of creeping bentgrass. 相似文献
16.
T. Yabuya 《Euphytica》1987,36(2):381-387
Summary Anthocyanins of colchicine-induced amphidiploids of I. laevigata × I. ensata were analyzed by the HPLC procedure and compared with those of parental species and F1 hybrids of I. laevigata × I. ensata. The amphidiploids were characterized by seventeen anthocyanins, and exhibited all anthocyanins of the parental species and the F1 hybrids. Malvidin 3RGac5G and petunidin 3RGac5G in anthocyanins detected were major pigments in the amphidiploids, which exhibited strongly the malvidin 3RGac5G-petunidin 3RGac5G type of I. ensata rather than the petunidin 3RGac5G-malvidin 3RGac5G type of I. laevigata. Moreover, a higher degree of anthocyanin content was observed in the amphidiploids and the F1 hybrids. Namely, the anthocyanin content of the amphidiploids and the F1 hybrids were 2.81 and 2.45 times as much as that of the mid-parent. This implies that there is a complementary effect on anthocyanin synthesis of parental genes in them. Finally, the utility of the amphidiploids was discussed.Contribution from the Laboratory of Plant Breeding, Faculty of Agriculture, Miyazaki Univ., No. 64. 相似文献
17.
Taing Aung Pamela Zwer Robert Park Philip Davies Parminder Sidhu Ian Dundas 《Euphytica》2010,174(2):189-198
Two diploid accessions of wild oat, CIav6956 and CIav7233, were identified as carrying seedling resistance to oat crown rust
(caused by Puccinia coronata f. sp. avenae; Pca). Two vigorous interploidy F1 hybrids were generated from crosses involving the hexaploid oat cultivar Wintaroo and the diploid oat Avena strigosa Schreb. accession CIav6956. An additional interploidy F1 hybrid, designated “F1-Aa1”, was produced from a cross of Wintaroo and the diploid oat accession CIav7233. All three hybrids
were more vigorous and taller than the cultivated parent Wintaroo. The three F1 hybrids contained full chromosome complements from both parents (2n = 4x = 28), but no seeds were obtained when the three F1 hybrids were selfed. Meiotic analyses of the hybrids indicated that they exhibited a high degree of inter-genome and intra-genome
pairing. Trivalent configurations were detected in 95–96% of meiotic cells and a minimum of three bivalents was present in
all cells. An average chiasma frequency of 7.2–7.9 per cell was observed for the three F1 hybrids. A fourth F1 hybrid was subsequently generated from a cross between the diploid oat accession CIav7233 and Wintaroo. One octaploid (2n = 8x = 56) was generated from this hybrid and progeny were resistant to two Pca races. The chromosome number of the octaploid progeny varied between 51 and 54 chromosomes. Development of a chromosome addition
line(s) with the crown rust resistance should be possible from these partial-octaploids. 相似文献
18.
Summary Progress was evaluated after four cycles of recurrent selection among S0 plants of Glycine max (L.) Merr. in which selection was either for maturity (MAT) or seed protein (PRO). The two populations, MAT and PRO, were developed from an initial population that was a combination of a line with 48.4% seed protein and two F2 populations segregating for male sterility. Intermating was facilitated by genetic male-sterility and the selection intensity was 20% in each cycle of the two populations. Selection for early maturity advanced the average maturity a significant 2.7±0.34 days cycle–1 and reduced seed yield a non-significant 9.1±2.95 g plant–1 cycle–1. Selection increased mean seed protein a significant 0.8±0.15 percentage points cycle–1 and decreased percent seed oil a non-significant 0.5±0.17 percentage points cycle–1. Correlation coefficients between seed protein and seed yield varied from 0.18 to –0.21 in the four cycles indicating plants with favorable combinations of seed yield and seed protein could be identified. Selection in these two populations would be effective for early maturity and for increased seed protein. 相似文献
19.
Interspecific cross‐hybrids of Nicotiana tabacum L. cv. (gla.) S ‘K326’ with Nicotiana alata 
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下载免费PDF全文 Jugou Liao Jinran Dai Shiyi Yang Xiaoli Zhou Longhui Ren Zhuangzhuang Chen Haili He Suiyun Chen 《Plant Breeding》2017,136(3):427-435
In order to introduce the Tomato Spotted Wilt Virus (TSWV) resistance from Nicotiana alata into Nicotiana tabacum, a cytoplasmic male sterility (CMS) line of N. tabacum (N. tabacum L. cv. (gla.) S ‘K326’), was successfully crossed with N. alata. Despite a high DNA content variability, F1 hybrids could be classified in two subgroups, a major one encompassing fertile hybrids morphologically similar to their tobacco maternal parent but TSWV sensitive, and a minor one displaying sterile hybrids showing an intermediate phenotype and TSWV resistant. In order to elucidate the unexpected fertility recovery of the fertile F1 plants, some N. alata fertility restoration ppr genes were cloned and were shown to be differentially expressed between parental lineages as well as between both F1 subgroups, suggesting that N. alata contains fertility restoring allele able to overcome the CMS of N. tabacum. 相似文献
20.
The Triticum dicoccoides-derived wheat line Zecoi-1 provides effective protection against powdery mildew. F3 segregation analysis of Chinese Spring × Zecoi-1 hybrids showed that resistance in line Zecoi-1 is controlled by a single dominant gene. Amplified fragment length polymorphism (AFLP) analysis of bulked segregants from F3s showing the homozygous resistant and susceptible phenotypes identified eight markers, of which four were associated with the resistance allele in repulsion phase. Following the assignment of these four repulsion phase AFLP markers to wheat chromosome 2B with the aid of Chinese Spring nulli-tetrasomic lines, they were physically mapped in the terminal breakpoint interval 0.89 (2BL-6)–1.00 (telomere) of chromosome 2BL. Genetic and physical mapping of simple sequence repeat markers from the distal half of chromosome 2BL located the wild emmer-derived powdery mildew resistance gene distal of breakpoint 0.89 in deletion line 2BL-6. Based on disease response patterns, genomic origin and chromosomal location the resistance gene in Zecoi-1 is temporarily designated MlZec1. 相似文献