263:. A problem in this procedure is being able to identify the lines carrying the trait of interest at each generation. The problem is particularly acute if the trait of interest is recessive, as it will be present only in a heterozygous condition after each backcross. The development of molecular markers provides an easier method of selection based on the genotype (marker) rather than the phenotype. Combined with doubled haploidy it becomes more effective. In marker assisted backcross conversion, a recipient parent is crossed with a donor line and the hybrid (F1) backcrossed to the recipient. The resulting generation (BC1) is backcrossed and the process repeated until the desired genotypes are produced. The combination of doubled haploidy and molecular marker provides the short cut. In the backcross generation one itself, a genotype with the character of interest can be selected and converted into homozygous doubled-haploid genotype. Chen
279:, a population is screened for a trait of interest and the genotypes at the two extreme ends form two bulks. Then the two bulks are tested for the presence or absence of molecular markers. Since the bulks are supposed to contrast in the alleles that contribute positive and negative effects, any marker polymorphism between the two bulks indicates the linkage between the marker and trait of interest. BSA is dependent on accurate phenotyping and the DH population has particular advantage in that they are true breeding and can be tested repeatedly. DH populations are commonly used in bulked segregant analysis, which is a popular method in marker assisted breeding. This method has been applied mostly to rapeseed and barley.
315:
recombinant chromosome substitution line, or stepped aligned recombinant inbred lines. Here, backcrossing is carried out until a desired level of recombination has occurred and genetic markers are used to detect desired recombinant chromosome substitution lines in the target region, which can be fixed by doubled haploidy. In rice, molecular markers have been found to be linked with major genes and QTLs for resistance to rice blast, bacterial blight, and
359:
genetic analysis and development of markers for useful traits in much less time. More specific benefits include the possibility of seed propagation as an alternative to vegetative multiplication in ornamentals, and in species such as trees in which long life cycles and inbreeding depression preclude traditional breeding methods, doubled haploidy provides new alternatives.
292:
species in which DHs are readily available. Doubled haploid populations are ideal for genetic mapping. It is possible to produce a genetic map within two years of the initial cross regardless of the species. Map construction is relatively easy using a DH population derived from a hybrid of two homozygous parents as the expected segregation ratio is simple,
371:
In haploids produced from anther culture, it is observed that some plants are aneuploids and some are mixed haploid-diploid types. Another disadvantage associated with the double haploidy is the cost involved in establishing tissue culture and growth facilities. The over-usage of doubled haploidy may
358:
The ability to produce homozygous lines after a single round recombination saves a lot of time for the plant breeders. Studies conclude that random DH’s are comparable to the selected lines in pedigree inbreeding. The other advantages include development of large number of homozygous lines, efficient
215:
In DH method only two types of genotypes occur for a pair of alleles, A and a, with the frequency of ½ AA and ½ aa, while in diploid method three genotypes occur with the frequency of ¼ AA, ½ Aa, ¼ aa. Thus, if AA is desirable genotype, the probability of obtaining this genotype is higher in haploid
623:
International
Symposium on Genetic Manipulation in Crops. 1988. Genetic manipulation in crops proceedings of the International Symposium on Genetic Manipulation in Crops, the 3rd International Symposium on Haploidy, the 1st International Symposium on Somatic Cell Genetics in Crops, Beijing, October
380:
Technological advances have now provided DH protocols for most plant genera. The number of species amenable to doubled haploidy has reached a staggering 250 in just a few decades. Response efficiency has also improved with gradual removal of species from recalcitrant category. Hence it will provide
343:
The relevance of DHs to plant breeding has increased markedly in recent years owing to the development of protocols for 25 species. Doubled haploidy already plays an important role in hybrid cultivar production of vegetables, and the potential for ornamental production is being vigorously examined.
219:
Studies were conducted comparing DH method and other conventional breeding methods and it was concluded that adoption of doubled haploidy does not lead to any bias of genotypes in populations, and random DHs were even found to be compatible to selected line produced by conventional pedigree method.
291:
relationships between species can be deduced. Genetic maps also provide a framework for the mapping of genes of interest and estimating the magnitude of their effects and aid our understanding of genotype/phenotype associations. DH populations have become standard resources in genetic mapping for
242:
with replicated trials is needed. This is possible with doubled haploidy organisms because of their true breeding nature and because they can conveniently be produced in large numbers. Using DH populations, 130 quantitative traits have been mapped in nine crop species. In total, 56 DH populations
339:
Uniformity is a general requirement of cultivated line in most species, which can be easily obtained through DH production. There are various ways in which DHs can be used in cultivar production. The DH lines themselves can be released as cultivars, they may be used as parents in hybrid cultivar
202:
or maternal haploids. Although these percentages appear small, the vast yield of tiny seeds and the early death of most seedlings provide significant numbers of viable hybrids and haploids in relatively small soil containers. This method of interspecific pollination serves as a practical way of
314:
Although QTL analysis has generated a vast amount of information on gene locations and the magnitude of effects on many traits, the identification of the genes involved has remained elusive. This is due to poor resolution of QTL analysis. The solution for this problem would be production of
233:
Most of the economic traits are controlled by genes with small but cumulative effects. Although the potential of DH populations in quantitative genetics has been understood for some time, it was the advent of molecular marker maps that provided the impetus for their use in identifying loci
305:
Genetic ratios and mutation rates can be read directly from haploid populations. A small doubled haploid (DH) population was used to demonstrate that a dwarfing gene in barley is located chromosome 5H. In another study the segregation of a range of markers has been analyzed in barley.
216:
method than in diploid method. If n loci are segregating, the probability of getting the desirable genotype is (1/2)n by the haploid method and (1/4)n by the diploid method. Hence the efficiency of the haploid method is high when the number of genes concerned is large.
700:
Thomas, W. T. B., B. Gertson and B.P. Forster. 2003. Doubled haploids in breeding p. 337-350. in :M. Maluszynski, K.J. Kasha, B.P. Forster and I. Szarejko (eds)., Doubled haploid production in crop plants:A Manual. Kluwer
Academic Publ., Dordrecht, Boston,
710:
Wang, Z., G. Taramino, D.Yang, G. Liu, S.V. Tingey, G.H. Miao, and G.L. Wang. 2001. Rice ESTs with disease-resistance gene or defense-response gene-like sequences mapped to regions containing major resistance genes or QTLs. Molecular
Genetics and Genomics.
340:
production or more indirectly in the creation of breeders lines and in germplasm conservation. Barley has over 100 direct DH cultivars. According to published information there are currently around 300 DH derived cultivars in 12 species worldwide.
367:
The main disadvantage with the DH population is that selection cannot be imposed on the population. But in conventional breeding selection can be practised for several generations: thereby desirable characters can be improved in the population.
296:
1:1. DH populations have now been used to produce genetic maps of barley, rapeseed, rice, wheat, and pepper. DH populations played a major role in facilitating the generation of the molecular marker maps in eight crop species.
714:
William, K.J., Taylor, S.P., Bogacki, P., Pallotta, M., Bariana, H.S., and
Wallwork, H. 2002. Mapping of the root lesion nematode (Pratylenchus neglectus) resistance gene Rlnn 1 in wheat. Theoretical and applied genetics
694:
Paterson, A.H., Deverna, J.W., Lanin, B., and
Tanksley, S. 1990. Fine mapping of quantitative trait loci using selected overlapping recombinant chromosomes in an interspecies cross of tomato. Genetics 124:735-741.
663:
Ardiel, G.S., Grewal, T.S., Deberdt, P., Rossnagel, B.G., and Scoles, G.J. 2002. Inheritance of resistance to covered smut in barley and development of tightly linked SCAR marker. Theoretical and applied genetics
673:
Chen, F.Q., D.Prehn, P.M. Hayes, D.Mulrooney, A. Corey, and H.Vivar. 1994. Mapping genes for resistance to barley stripe rust (Puccinia striiformis f. sp. hordei). Theoretical and
Applied Genetics. 88:215-219.
164:(anther and microspore culture). Androgenesis is the preferred method. Another method of producing the haploids is wide crossing. In barley, haploids can be produced by wide crossing with the related species
704:
Thomas, W.T.B., Newton, A.C., Wilson, A., Booth, A., Macaulay, M., and Keith, R. 2000. Development of recombinant chromosome substitution lines: A barley resource. SCRI Annual Report 1999/2000, 99-100.
78:, whereas doubled haploidy achieves it in one generation. Dihaploid plants derived from tetraploid crop plants may be important for breeding programs that involve diploid wild relatives of the crops.
718:
Winzeler, H., Schmid, J., and Fried, P.M. 1987. Field performance of androgenetic doubled haploid spring wheat line in comparison with line selected by the pedigree system. Plant breeding 99:41-48.
393:
688:
Kearsey, M. J. 2002. QTL analysis: Problems and (possible) solutions. p. 45-58. In: M.S. Kang (ed.), Quantitative genetics, genomics and plant breeding. CABI Publ., CAB International.
676:
Friedt, W., Breun, J., Zuchner, S., and
Foroughi-Wehr, B. 1986. Comparative value of androgenetic doubled haploid and conventionally selected spring barley line. Plant Breeding 97:56-63.
350:
to select lines with high pharmacological activity. Another interesting development is that fertile homozygous DH lines can be produced in species that have self-incompatibility systems.
721:
Yi, H.Y., Rufty, R.C., Wernsman, E.A., and
Conkling, M.C. 1998. Mapping the root-knot nematode resistance gene (Rk) in tobacco with RAPD markers. Plant Disease 82:1319-1322.
691:
Maluszynski, M.., Kasha K. J., Forster, B.P., and
Szarejko, I. 2003. Doubled haploid production in crop plants: A manual. Kluwer Academic Publ., Dordrecht, Boston, London.
327:
Traditional breeding methods are slow and take 10–15 years for cultivar development. Another disadvantage is inefficiency of selection in early generations because of
707:
Thomas, W.T.B., Powell, W., and Wood, W. 1984. The chromosomal location of the dwarfing gene present in the spring barley variety Golden
Promise. Heredity 53:177-183.
43:, then by induced or spontaneous chromosome doubling, a doubled haploid cell is produced, which can be grown into a doubled haploid plant. If the original plant was
372:
reduce genetic variation in breeding germplasm. Hence one has to take several factors into consideration before deploying doubled haploidy in breeding programmes.
252:
697:
Schon, C., M. Sanchez,T. Blake, and P.M. Hayes. 1990. Segregation of Mendelian markers in doubled haploid and F2 progeny of barley cross. Hereditas 113:69-72.
390:
116:, and barley are the most responsive species for doubled haploid production. Doubled haploid methodologies have now been applied to over 250 species.
456:
B. Barnabás; B. Obert; G. Kovács (1999). "Colchicine, an efficient genome-doubling agent for maize (Zea mays L.) microspores cultured in anthero".
148:, or chromosome elimination after wide crossing. The haploid embryo is rescued, cultured, and chromosome-doubling produces doubled haploids. The
667:
Blakelsee, A.F., Belling, J., Farhnam, M.E., and Bergner, A.D.1922. A haploid mutant in the Jimson weed, Datura stramonium. Science 55:646-647.
267:(1994) used marker assisted backcross conversion with doubled haploidy of BC1 individuals to select stripe rust resistant lines in barley.
331:. These two disadvantages can be over come by DHs, and more elite crosses can be evaluated and selected within less time.
287:
Genetic maps are very important to understand the structure and organization of genomes from which evolution patterns and
685:
Kasha, K. J., and Kao, K. N. 1970. High frequency haploid production in barley (Hordeum vulgare L.). Nature 225: 874-876.
670:
Burk, L.G., Gerstel, D.U., and Wernsman, E.A. 1979. Maternal haploids of Nicotiana tabacum L. from seed. Science 206:585.
628:, v. 22. (London: Published for the International Rice Research Institute and Academia Sinica by Cassell Tycooly), p.318.
100:
culture technique for the production of haploids in the laboratory. Haploid production by wide crossing was reported in
679:
Guha, S., and Maheswari, S. C. 1964. In vitro production of embryos from anthers of Datura. Nature 204:497.
96:. Subsequently, haploids were reported in many other species. Guha and Maheshwari (1964) developed an
276:
682:
Immonen, S., and H. Anttila. 1996. Success in rye anther culture. Vortr. Pflanzenzuchtg. 35:237-244.
745:
735:
235:
346:
24:
cells undergo chromosome doubling. Artificial production of doubled haploids is important in
64:
8:
473:
182:
740:
176:
92:
477:
465:
166:
397:
238:(QTL) effects are small and highly influenced by environmental factors, accurate
170:; fertilization is affected, but during the early stages of seed development the
141:
328:
25:
403:
75:
729:
316:
207:, either as an alternative method or complementary method to anther culture.
36:
161:
469:
404:
Doubled Haploids: A simple method to improve efficiency of maize breeding.
239:
153:
67:(and the doubled dihaploids are, respectively, tetraploid or hexaploid).
40:
145:
71:
260:
199:
195:
60:
56:
55:
may be used for the doubled haploids. Haploid organisms derived from
288:
256:
132:
113:
74:
procedures take six generations to achieve approximately complete
174:
chromosomes are eliminated leaving a haploid embryo. In tobacco (
126:
105:
86:
The first report of the haploid plant was published by Blakeslee
44:
21:
259:
or related species into a recipient elite line through repeated
101:
97:
48:
32:
157:
455:
438:
436:
434:
432:
422:
Jain, S. Mohan, S. K. Sopory, and R. E. Veilleux. 1996.
429:
511:
509:
223:
344:DHs are also being developed in the medicinal herb
506:
270:
228:
119:
727:
198:survive and can readily be identified as either
426:. Dordrecht: Kluwer Academic Publishers. p.317.
626:Natural resources and the environment series
424:In vitro haploid production in higher plants
210:
391:Doubled Haploids to Improve Winter Wheat
234:controlling quantitative traits. As the
362:
334:
728:
381:greater efficiency of plant breeding.
319:in a map produced from DH population.
255:, genes are introgressed from a donor
246:
353:
203:producing seed-derived haploids of
13:
300:
224:Applications of DHs plant breeding
14:
757:
322:
124:Doubled haploids can be produced
39:cells or from other cells of the
31:Haploid cells are produced from
640:
631:
617:
604:
591:
582:
569:
282:
271:Bulked segregant analysis (BSA)
229:Mapping quantitative trait loci
136:. Haploid embryos are produced
20:(DH) is a genotype formed when
556:
543:
522:
497:
484:
449:
416:
375:
194:, 0.25 to 1.42 percent of the
120:Production of doubled haploids
1:
409:
243:were used for QTL detection.
384:
7:
309:
10:
762:
637:Immonen and Anttila, 1996.
104:(Kasha and Kao, 1970) and
81:
277:bulked segregant analysis
211:Genetics of DH population
503:Forster and Thomas, 2003
160:and flower culture) and
47:, the haploid cells are
236:quantitative trait loci
180:), wide crossing with
588:STAIRS, Kearsey 2002.
470:10.1007/s002990050674
347:Valeriana officinalis
190:is used to pollinate
186:is widely used. When
63:are sometimes called
363:Disadvantages of DHs
335:Cultivar development
253:backcross conversion
458:Plant Cell Reports
396:2015-09-12 at the
247:Backcross breeding
183:Nicotiana africana
112:, 1979). Tobacco,
650:, 1986; Winzeler
354:Advantages of DHs
177:Nicotiana tabacum
93:Datura stramonium
53:doubled monoploid
753:
655:
644:
638:
635:
629:
621:
615:
608:
602:
595:
589:
586:
580:
575:RCSLs, Paterson
573:
567:
560:
554:
547:
541:
532:, 2002; William
526:
520:
513:
504:
501:
495:
488:
482:
481:
453:
447:
440:
427:
420:
167:Hordeum bulbosum
152:methods include
761:
760:
756:
755:
754:
752:
751:
750:
726:
725:
724:
659:
658:
645:
641:
636:
632:
622:
618:
609:
605:
596:
592:
587:
583:
574:
570:
561:
557:
548:
544:
527:
523:
514:
507:
502:
498:
489:
485:
464:(10): 858–862.
454:
450:
441:
430:
421:
417:
412:
398:Wayback Machine
387:
378:
365:
356:
337:
325:
312:
303:
301:Genetic studies
285:
273:
249:
231:
226:
213:
142:parthenogenesis
122:
84:
51:, and the term
18:doubled haploid
12:
11:
5:
759:
749:
748:
746:Plant genetics
743:
738:
736:Plant breeding
723:
722:
719:
716:
712:
708:
705:
702:
698:
695:
692:
689:
686:
683:
680:
677:
674:
671:
668:
665:
660:
657:
656:
639:
630:
616:
603:
590:
581:
568:
555:
542:
521:
505:
496:
483:
448:
428:
414:
413:
411:
408:
407:
406:
400:
386:
383:
377:
374:
364:
361:
355:
352:
336:
333:
329:heterozygosity
324:
323:Elite crossing
321:
311:
308:
302:
299:
284:
281:
272:
269:
248:
245:
230:
227:
225:
222:
212:
209:
121:
118:
83:
80:
26:plant breeding
9:
6:
4:
3:
2:
758:
747:
744:
742:
739:
737:
734:
733:
731:
720:
717:
713:
709:
706:
703:
699:
696:
693:
690:
687:
684:
681:
678:
675:
672:
669:
666:
662:
661:
653:
649:
643:
634:
627:
620:
613:
607:
600:
594:
585:
578:
572:
565:
559:
552:
546:
539:
535:
531:
525:
518:
512:
510:
500:
493:
487:
479:
475:
471:
467:
463:
459:
452:
445:
439:
437:
435:
433:
425:
419:
415:
405:
402:Video :
401:
399:
395:
392:
389:
388:
382:
373:
369:
360:
351:
349:
348:
341:
332:
330:
320:
318:
317:sheath blight
307:
298:
295:
290:
280:
278:
268:
266:
262:
258:
254:
244:
241:
237:
221:
217:
208:
206:
201:
197:
193:
189:
185:
184:
179:
178:
173:
169:
168:
163:
159:
155:
151:
147:
143:
139:
135:
134:
129:
128:
117:
115:
111:
107:
103:
99:
95:
94:
89:
79:
77:
73:
70:Conventional
68:
66:
62:
58:
54:
50:
46:
42:
38:
34:
29:
27:
23:
19:
715:104:874-879.
711:265:303-310.
664:104:457-464.
651:
647:
642:
633:
625:
619:
611:
606:
598:
593:
584:
576:
571:
563:
558:
550:
545:
537:
533:
529:
524:
516:
499:
491:
486:
461:
457:
451:
443:
442:Maluszynski
423:
418:
379:
370:
366:
357:
345:
342:
338:
326:
313:
304:
293:
286:
283:Genetic maps
274:
264:
261:backcrossing
250:
232:
218:
214:
204:
191:
187:
181:
175:
171:
165:
162:androgenesis
149:
137:
131:
125:
123:
109:
91:
87:
85:
76:homozygosity
69:
52:
30:
17:
15:
536:, 2002; Yi
376:Conclusions
240:phenotyping
188:N. africana
172:H. bulbosum
154:gynogenesis
57:tetraploids
41:gametophyte
730:Categories
410:References
205:N. tabacum
200:F1 hybrids
192:N. tabacum
146:pseudogamy
90:(1922) in
72:inbreeding
65:dihaploids
61:hexaploids
490:Winzeler
385:Tutorials
49:monoploid
741:Genetics
394:Archived
310:Genomics
289:syntenic
257:cultivar
150:in vitro
133:in vitro
114:rapeseed
701:London.
654:, 1987.
646:Friedt
614:, 2001.
601:, 2000.
597:Thomas
579:, 1990.
566:, 1990.
553:, 1984.
549:Thomas
540:, 1998.
528:Ardiel
519:, 2003.
515:Thomas
494:, 1987.
478:5397111
446:, 2003.
196:progeny
138:in vivo
127:in vivo
106:tobacco
82:History
45:diploid
22:haploid
652:et al.
648:et al.
612:et al.
599:et al.
577:et al.
564:et al.
562:Schon
551:et al.
538:et al.
534:et al.
530:et al.
517:et al.
492:et al.
476:
444:et al.
265:et al.
110:et al.
108:(Burk
102:barley
98:anther
88:et al.
33:pollen
624:1984.
610:Wang
474:S2CID
158:ovary
294:i.e.
466:doi
275:In
251:In
140:by
130:or
59:or
37:egg
35:or
732::
508:^
472:.
462:18
460:.
431:^
144:,
28:.
16:A
480:.
468::
156:(
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.