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1.
Summary Four indica cultivars viz. Kalinga-I, Ptb. 10, IR 27280-13-3-3-3 and Co. 41 were found to possess male sterile cytoplasm with fertility restoring genes while the cultivar Krishna was found to maintain the male sterility in all the cases. All the plants in the F1 of Kalinga-I × Krishna were observed to be completely male sterile and continued to show complete pollen sterility in subsequent backcross generations when backcrossed with recurring pollen parent, Krishna. Thus, it was posible to develop a new cytoplasmic-genetic male sterile line in indica rice (Krishna A) with Kalinga-I male sterile cytoplasm and this male sterile cytoplasm was found to be genetically different from others. Further, the newly developed male sterile line (Krishna A) was observed to be tolerant for low temperature at seedling stage.  相似文献   

2.
Summary From 28 Indica-Japonica crosses, two Indica cultivars, V.20B and Sattari were identified to possess male sterile cytoplasm with fertility restoring genes. It was possible to develop a new Japonica cytoplasmic genetic male sterile line (Zhunghua-1) on Indica male sterile cytoplasm (V 20B) by repeated backcrossing the complete pollen sterile plants of V 20B x Zhunghua-1 to the recurring male parent, Zhunghua-1. The study indicated that it would be possible to develop male sterile lines rom indica-japonica crosses only when there is sufficient amount of reciprocal differences with respect to pollen sterility. Further, it was inferred that it would be easier to develop Japonica male sterile lines on Indica cytoplasm than developing Indica male sterile line with japonica cytoplasm.  相似文献   

3.
H. Ghiasi  K. A. Lucken 《Euphytica》1982,31(1):253-259
Summary Many conventional hard red spring wheat (Triticum aestivum L. em Thell) lines, including several North Dakota cultivars, carry a gene (or genes) which restore partial male fertility to male sterile plants with Triticum timopheevi Zhuk. cytoplasm. Since this gene has no fertility restoration function in T. aestivum cytoplasm, the postulation can be made that it is being retained in conventional lines because of pleiotropic effects, favorable linkages or chance. The research reported in this paper examined these possibilities. Forty F6 lines, derived from a single F2 plant which was heterozygous for a gene (or genes) for partial fertility restoration, were evaluated for two years in a yield trial planted at Fargo, North Dakota. The 40 lines were testcrossed to a male sterile line having T. timopheevi cytoplasm, and the mean seed set of testcrosses was used as a measure of a line's fertility restoration potential. Twenty-seven lines had the gene for partial fertility, and 13 lines apparently lacked this gene. The 40 lines differed for heading date, anther extrusion, plant height, grain yield, 200-kernel weight, test weight, and grain protein percentage. However, comparisons of lines having the restorer gene with those lacking the gene did not provide any obvious explanation for the retention of the partial fertility restorer gene in the breeding stocks of the North Dakota conventional hard red spring wheat breeding program. The possibility that the restorer gene was linked with genes for resistance to stem rust or leaf rust also was evaluated by testing lines for their reaction to several races of rust. No conclusive association was found.Contribution from the Agric. Exp. Sta., North Dakota State University, Fargo, ND 58105, Journal Article no.  相似文献   

4.
Summary From backcrosses of three interspecific hybrids (A. fistulosum x A. cepa) with a. cepa 14 diploid and 2 triploid plants were recovered.In this BC1 population introgression of A. fistulosum genetic material into the A. cepa nuclear genome was studied using two isozyme markers: Got-1 and Got-2. Both loci carried two alleles. A. cepa was monomorphic for both markers. A. fistulosum was polymorphic for Got-2. Based on their Got isozyme pattern seven out of the 14 diploid BC1 plants had a recombinant genotype. The loci appeared to be unlinked. Differences were observed in nuclear DNA contents between the diploid BC1 plants, indicating that gametes produced by the interspecific hybrids contained different combinations of chromosomal material from A. cepa and A. fistulosum.Abbreviations Adh alcohol dehydrogenase - Got glutamate oxaloacetate transaminase - Idh isocitrate dehydrogenase - Pgi phosphoglucoisomerase - Pgm phosphoglucomutase  相似文献   

5.
The induction of haploid plants from F1 hybrids between CMS shallot with Allium galanthum cytoplasm and common onion was examined. Starting with 535 unpollinated flowers cultured in B5 medium 25 seedlings from part henogenetic embryos were obtained of which 13 seedlings survived. Eleven seedlings were determined as haploid plants (2n = x = 8) and 2 seedlings were doubled haploid plants (2n = 2x = 16). All haploid and doubled haploid plants preserved chloroplast DNA (cpDNA) and mitochondrial DNA (mtDNA) from A. galanthum. Segregation in different characters was observed among the haploid plants. The haploid and doubled haploid plants exhibited the different combinations of genes from shallot and common onion. Crossing of the doubled haploid plants with other shallot strains, common onion cultivars or related species may produce excellent F1 hybrids for bulb production. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

6.
The beet armyworm (Spodoptera exigua Hübner)is the most important pest in tropical Alliumcultivations. All shallot (Allium cepa L. group Aggregatum) cultivars are susceptible to this pest. Therefore accessions from three wild Alliumspecies, namely A. galanthum Kar. et Kir., A. fistulosum L. and A. royleiStearn, next to A. cepa L. were used to screen for resistance. First of all, a reliable bio-assay had to be developed. To this end transparent plastic cages with in total 5 plants of one accession per cage were placed on per lite in a heated greenhouse. Five 3-day old larvae were inoculated on each plant. Eight days after inoculation the number of surviving larvae per cage and the mean fresh weightper larva was determined. The lowest larval survival (36%) was found on A. roylei. This was not, however, significantly different from other Allium accessions. Significant differences were found in the fresh weight per larva fed on different Allium accessions. The larvae survived on A. roylei had a very low fresh weight (10.3 mg per larva), while those on an accession of A. fistulosum had the highest fresh weight (45.1 mg per larva). The larval fresh weight on A. roylei was lower than all the other accessions except from the tropical shallot cultivar Bawang Bali. To check whether or not a toxic compound was involved in the resistance present in A. roylei, tenaccessions from four Allium species were screened. Five 3-day old larvae were inoculated on regularly replaced leaf material of each accession ofAllium species. No significant differences were found in mean fresh weight per larva and mean survival of larvae among different accessions. There were also no significant differences in pupal weight and developmental time. All larvae became pupae 10 days after inoculation. The data indicate that there is no toxic compound present in A. roylei. These results are underlined by the observation in the greenhouse bio-assay that A. roylei plants were equally damaged by the beet armyworm compared to otherAllium species. The results obtained so far therefore suggest that introduction of resistance to S. exigua via the exploitation of variation for resistance to the beet armyworm in A. roylei is unclear and that genetic engineering using Cry sequences could provide a way forward. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

7.
Yoshio Sano 《Euphytica》1985,34(3):587-592
Summary To study differential nucleus-cytoplasm interactions between the two cultivated rice species, Oryza sativa and O. glaberrima, cytoplasmic substitution lines were made by using a glaberrima strain (G) and an Indica strain of sativa (S). The G cytoplasm had no adverse effect on pollen development when combined with the nucleus of S. On the other hand, when the S cytoplasm was combined with the G nucleus, the substitution line showed no seed set because of male sterility although the pollen grains were normally stained with I2-KI solution. A dominant gene derived from S strain seemed to cause anther indehiscence in the substitution line. Further, a restorer gene (Rf j)from Akebono of Japonica type was effective on pollen restoration in the male sterile line, suggesting that the S cytoplasm is the same as those of Japonica type in terms of a fertility-restoring system.This paper is Genetic studies of speciation in cultivated rice. 4.  相似文献   

8.
Interspecific hybridization is an effective method to generate a new crop that gains available functions in a short time. Interspecific hybrids (2n= 16) betweenAllium fistulosumL. (2n= 16) andAllium schoenoprasumL. (2n= 16) were produced by reciprocal crossings through ovary culture, but the hybrids were much fewer in the combination usingA. schoenoprasumas a seed plant. All the hybrids have eight long chromosomes originated fromA.fistulosumand eight short chromosomes originated fromA. schoenoprasum. In addition, the hybridity was confirmed by randomly amplified polymorphic DNA (RAPD) analysis and cleaved amplified polymorphic sequence (CAPS) analysis of the rDNA internal transcribed spacer (ITS) region. The interspecific hybrids showed a vigorous growth habit; their foliage was slightly bloomy and deep green. The hybrids did not form bulbs, but rather propagated vegetatively by tillering. Carotene contents of the hybrids and both parents were quantified using high-performance liquid chromatography (HPLC). The contents of all edible parts of the hybrids were approximately seven times higher than those of either parent. These results indicate that the hybrid is a new and carotene-rich vegetable ofAlliumspecies.  相似文献   

9.
In several autogamous and vegetatively propagated crops, DNA markers have been used for cultivar identification. However, allogamous crops such as bunching onion (Allium fistulosum L.) are recalcitrant to marker-aided cultivar identification, as well as hybrid seed purity tests, due to the high degree of genetic heterogeneity within each cultivar. To aid cultivar identification and ensure its accuracy in bunching onion, we proposed the “SSR-tagged breeding” scheme in our previous study. The feasibility of this scheme was investigated here using a landrace of bunching onion with two populations tagged with two or four selected SSR markers. Compared with a control population, no significant differences were detected in the agronomic traits of the SSR-tagged populations. The targeted SSR loci were genetically uniform within each population whereas other loci maintained high heterogeneity. These results demonstrate that the SSR-tagged breeding scheme, even with a very small number of markers, is efficient for the identification of newly bred cultivars, and consequently for F1 purity tests, in allogamous crops in which inbreeding depression is as severe as in bunching onion.  相似文献   

10.
Summary A new method for determining ploidy levels in cytochimeral plants was developed by examining the maximum number of nucleoli per cell. Colchicine-treated plants of Allium wakegi Araki and A. fistulosum L., which have different ploidy levels in the first (LI), the second (LII), and the third (LIII) germ layer, were used together with untreated 2-2-2 plants of the same species. Nucleoli in guard cells for LI and in mesophyll cells for LII were stained in a 50% AgNO3 aqueous solution at 55° C for three hours under dark, humid conditions. In both species the ploidy levels of LI determined by the maximum number of nucleoli per guard cell accorded well with those determined by guard cell length. In A. fistulosum the ploidy levels of LII determined by the maximum number of nucleoli per mesophyll cell clearly agreed with those determined by pollen size. This method provided more precise and efficient identification for LI and LII ploidy than the conventional methods of using guard cell length for LI and pollen size for LII.  相似文献   

11.
A “two-line system” using photoperiod-sensitive cytoplasmic male sterility (PCMS) caused by Aegilops crassa cytoplasm under long-day photoperiods (≧15 h) has been proposed as a means of producing hybrid varieties in common wheat (Triticum aestivum). The PCMS line is maintained by self-pollination under short-day conditions, and hybrid seeds can be produced through outcrossing of the PCMS line with a pollinator line under long-day conditions. Our previous studies revealed that PCMS lines showing complete male sterility under long-day conditions are necessary for practical hybrid wheat breeding, especially to obtain high hybrid purity in F1 seeds. Furthermore, practical PCMS lines should have high seed fertility under short-day conditions, which is associated with female fertility. Wheat cv. Norin 26 with Ae. crassa cytoplasm exhibits high seed fertility under short-day conditions, and cv. Fujimikomugi with Ae. crassa cytoplasm shows high male sterility under long-day conditions. Here we developed practical PCMS lines derived from the F1 generation of Norin 26 and Fujimikomugi (with Ae. crassa cytoplasm) that were then backcrossed to elite wheat lines.  相似文献   

12.
Summary Interspecific cytoplasm substitution lines of Oryza sativa and O. glaberrima, i.e. (sativa)-glaberrima and (glaberrima)-sativa, have been bred by means of successive backcrosses, using three japonica varieties of sativa and two glaberrima strains.In all the six substitution lines with the cytoplasm of the glaberrima strains, the fertility increased with succeeding backcrosses, and eventually completely fertile plants whith the characteristics of the parental japonica variety appeared. This indicates that the glaberrima cytoplasm exerted no effect on the genome manifestation of these japonica varieties. Of the five substitution lines with the cytoplasm of each of the japonica varieties, four lines produced male sterile (M.S.) plants only in the backcross generations. In the remaining substitution line with the cytoplasm of the japonica variety Akebono, there was simultaneous segregation for male sterile (M.S.) and pollen fertile plants bearing indehiscent anthers (ID.M.F.) in the backcross generations. In the compulsively selfed progeny of ID.M.F. plants, pollen fertile plants with dehiscent anthers (D.M.F.) occurred with M.S- and ID.M.F. plants. Morphologically, these three types were supposed to have the same genetic background as the glaberrima parent. It was established that D.M.F.-and ID.M.F. plants were homozygous and heterozygous for a dominant nuclear gene restoring pollen fertility, respectively, and the M.S. plants and the two glaberrima strains used in this study carried a recessive gene for pollen sterility in homozygous condition. The restorer gene was assumed to derive from the japonica variety Akebono. The expression of the restorer gene was of the sporophytic type. The pollen sterility of the substitution lines that possessed the cytoplasm of the japonica varieties was of cytoplasmon-genic nature.  相似文献   

13.
Summary To facilitate the introgression of desirable traits of Allium fistulosum into the genome of A. cepa, several accessions of the hybrid between these species were pollinated with A. cepa as the recurrent parent, and in vitro ovary and ovule culture were performed to obtain an increase in the recovery of backcross progeny. Compared to the results obtained from seed development in planta, the increase in the number of backcross progeny was generally very limited, and in some cases even a decrease was found. Raising the sucrose concentration in the ovary culture medium resulted in a higher frequency of ovules developing back seed coats but this was not followed by an increase in the number of backcross progeny obtained. Pollen tube growth of A. cepa was disturbed in the styles of the interspecific hybrids. Per ovule, frequencies of micropylar penetration exceeded frequencies of backcross progeny only to a limited extent. Hence, it was concluded that in the tested interspecific hybrid accessions the attainable gain in viable backcross progeny by the application of in vitro culture techniques is limited by strong pre-fertilization barriers acting at the level of stylar incongruity.  相似文献   

14.
J. H. Oard  J. Hu  J. N. Rutger 《Euphytica》1991,55(2):179-186
Summary Twenty-six male sterile plants grown in the field were recovered in the M7 generation from ethyl methane sulfonate-treated material of the rice cultivar M-201. Fertility increased five-fold when ratooned plants from the field were grown in a growth chamber with a 12 hour daylength. Crosses between mutant and normal fertile cultivars produced fertile F1 plants. Female fertility was normal as judged by percent seed set from unbagged panicles of parental and recombinant lines. Transgressive segregation for fertility was observed for all crosses in the F2 and F3 generations. Five of 37 F3 male sterile plants showed moderate levels of seed fertility under winter greenhouse conditions and reduced seed set when transplanted to summer field plots. Fertility data from reciprocal crosses suggested cytoplasmic factors had little or no effect on levels of male sterility in the mutant lines. Chi-squared analyses of F2 and F3 generation results indicated male sterility of the mutants is conditioned by two nuclear genes with epistatic effects.  相似文献   

15.
The male sterility system in hybrid seed production can eliminate the cost of emasculation and ensure seed hybridity through avoidance of self pollination. GMS and CMS are two types of male sterility system that currently employed in pepper breeding. Conversion from GMS to CMS will increase the male sterility proportion of female parent from 50 to 100%. In this study, segregation analysis of four male sterile mutants consisting of one CMS mutant (CA1) and three GMS mutants (GA1, GA3 and GA4) showed that each had single recessive gene inheritance. A modified complementation test was performed by replacing male sterile mutants with their maintainer line as male parent. The nuclear restorer gene for CMS was independent of all nuclear restorer genes for GMS and all nuclear restorer genes for GMS were independent each other. Further observation on CMS and GMS male sterility loci revealed that GA1 and GA3 had mutated in both nuclear restorer genes for CMS and GMS, while CA1 and GA4 each carried mutation in single male sterility system of nuclear restorer gene for CMS and GMS, respectively. Conversion from GMS to CMS in the case of lines carried mutations in both sterility systems required only S-type cytoplasm donor, while lines carried mutation in single nuclear restorer gene for GMS required not only S-type cytoplasm but also rf allele donors. The important finding is the broader function of maintainer line in certain male sterility system that can be used as a maintainer or restorer line for other male sterility systems. We also confirmed that line CC1 is the general restorer for both CMS and GMS systems.  相似文献   

16.
Heterosis is an important way to improve yield and quality for many crops. Hybrid rice and hybrid maize contributed to enhanced productivity which is essential to supply enough food for the increasing world population. The success of hybrid rice in China has led to a continuous interest in hybrid wheat, even when most research on hybrid wheat has been discontinued in other countries for various reasons including low heterosis and high seed production costs. The Timopheevii cytoplasmic male sterile system is ideal for producing hybrid wheat seeds when fertility restoration lines with strong fertility restoration ability are available. To develop PCR-based molecular markers for use in marker-assisted selection of fertility restorer lines, two F2 populations derived from crosses R18/ND36 and R9034/ND36 were used to map fertility restoration genes in the two elite fertility restorer lines (R-lines) R18 and R9034. Over 678 SSR markers were analyzed, and markers closely linked to fertility restoration genes were identified. Using SSR markers, a major fertility restoration gene, Rf3, was located on the 1B chromosome in both populations. This gene was partially dominant in conferring fertility restoration in the two restorer lines. SSR markers Xbarc207, Xgwm131, and Xbarc61 are close to this gene. These markers may be useful in marker-assisted selection of new restorer lines with T. timopheevii cytoplasm. Two minor QTL conferring fertility restoration were also identified on chromosomes 5A (in R18) and 7D (in R9034) in two R-lines.  相似文献   

17.
Summary Digitaria eriantha is a subtropical grass which is widely sown as a pasture species in South Africa and cultivars have recently been released in Australia. The species is variable in seed production and in other agronomic attributes. This paper describes a breeding program designed to combine the seed production of cv. Premier with the high productivity in winter-spring of an almost sterile genotype.Hybrids between the two accessions were either triploid and sterile, or diploid with low fertility. The F2 to F5 generations were selected intensively for fertility and, at two contrasting sites, for spring productivity, with both maternal and paternal selection. The F6 generation was grown as replicated swards and yield in spring, and fertility, were used for selection of elite F5 plants to comprise the parents of a new cultivar (cv. Advance).In evaluation trials, spring dry matter production of Advance averaged 40% higher than that of Premier. On average, seed production of Advance was 11% lower than that of Premier and botanical fertility was consistently about half that of Premier. Experimental yields of cleaned seed of Advance were up to 138 kg/ha. In commerce, seed yields of Advance are likely to be lower than those of Premier unless higher inflorescence densities than Premier can be achieved.  相似文献   

18.
Summary Five cytoplasmic male sterile lines of Nicotiana tabacum homozygous for a dominant rootless mutation [Rac-] were used as female parents in crosses with three male fertile varieties. Androgenetic haploids were selected by their ability to form plantlets with a normal root system, whereas hybrid plantlets failed to grow. High frequencies of androgenetic haploid plants were obtained with N. debneyi cytoplasm, and with one paternal genotype. Chromosome doubling was performed using three different methods (pollination, in vitro culture, acenaphthen) and cytoplasmic male sterile doubled haploid plants have been obtained. The results demonstrate the efficiency of this method for a rapid cytoplasm transfer in Nicotiana tabacum; the integrity of the cytoplasm is conserved. For the first time, we possess a counter selectable marker universally usable for Nicotiana tabacum and closely related species.  相似文献   

19.
Koji Murai 《Euphytica》2001,117(2):111-116
A `two-line system' using photoperiod-sensitivecytoplasmic male sterility (PCMS) caused by Aegilops crassa cytoplasm has been proposed as a newmeans of producing hybrid wheat. The PCMS line ismaintained by self-pollination under short-dayconditions (14.5 h light period), and F1 seedscan be produced by outcrossing of the PCMS line witha pollinator under long-day conditions (15 h lightperiod). As the levels of male sterility in PCMSlines under the long-day conditions is a crucialfactor in determining hybrid purity of the F1seeds, a study was conducted into the effect ofseeding rate on male sterility in PCMS lines. Threedifferent density levels were tested using analloplasmic line of Japanese wheat cultivar `Norin 26'which exhibits PCMS. Levels of male sterility of thePCMS line increased at sparse planting, because tiller(ear) number per plant increased at low seedingdensity and late-appearing ears tended to exhibithigher levels of male sterility than early-appearingears. On the other hand, male sterility levels of thePCMS lines depended on genotype, e.g., the PCMS`Fujimikomugi' was completely male sterile, whereasthe PCMS `Norin 26' showed partial male sterility. APCMS line showing complete male sterility, such as thePCMS `Fujimikomugi', should produce F1 seeds withhigh purity. However, the PCMS `Fujimikomugi' showeda lower female fertility. For practical use, it isnecessary to produce PCMS lines having high malesterility with high female fertility under long-dayconditions.  相似文献   

20.
Summary Effect of A1 male sterile cytoplasm on smut severity in pearl millet (Pennisetum glaucum (L.) R.Br.) was studied by comparing 35 pairs of F1 hybrids, each pair carrying male sterile and normal cytoplasm. Mean smut severity was not significantly different in the hybrids carrying male sterile or normal cytoplasm. This suggests that in pearl millet male sterile cytoplasm is not associated with higher smut susceptibility. Partitioning of variance into different components showed that pollinators, A/B line pairs and their interaction primarily influenced smut severity of hybrids. Smut susceptibility might be attributed to effects of cytoplasm × nuclear interactions.  相似文献   

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