An extended genetic map of rye (Secale cereale L.)

A genetic linkage map of rye consisting of 92 markers was constructed by using isozyme and molecular marker techniques. For this purpose an F₂ population of 137 individuals was established on which RFLP studies with homologous and heterologous probes were performed. After establishing a reliable polymerase chain reaction (PCR) protocol, 280 random primers were screened for polymorphisms and 17 random amplified polymorphic DNA (RAPD) loci were mapped. The digestion of the template DNA prior to PCR increased the degree of polymorphism. Previously published markers could also be integrated into this map by using the JoinMap computer program. The resulting linkage map comprises a total of 127 markers and spans a distance of about 760 cM.     

Anther-Culture ability in Secale cereale L.

Success in anther culture of rye (Secale cereale L.) has mainly been restricted to genotypes whose genome is partly determined by S. vavilovii Grossh. The aim of this study was to identify true S. cereale genotypes with anther-culture ability. The plant material used included the semi-wild standard genotype SC35, six single crosses of the ‘Petkus’ and 10 of the ‘Carsten’ gene pool, plus a double cross between SC35 and one of the ‘Carsten’ single crosses. Three anther-culture experiments were performed. Several single crosses within the ‘Carsten’ gene pool produced green plants. The ‘Petkus’ single crosses tested did not show anther-culture ability. As expected, the induction and regeneration rates of SC35 were higher than those of all other genotypes tested. The performance of the double cross was intermediate between its parents. The results demonstrate for the first time that anther culture in rye is a valuable tool in plant breeding. The data also show the possibility of transferring anther-culture ability from high- to low-responding genotypes.     

Seed storage potential of population varieties and hybrid varieties and their breeding components in rye (Secale cereale L.)*

Seeds of population varieties, hybrid varieties, cytogenetic male sterility (CMS) single cross lines and CMS inbred lines of rye (Secale cereale L.) were stored to determine the respective rates of germination loss with a view to their storage potential. The seeds were stored under controlled conditions at a seed moisture content of 14% and a temperature of 30°C for periods of up to 80 days. The storage potential decreased in the order: hybrid varieties > population varieties > CMS single cross lines > CMS inbred lines. However, the rates of germination loss showed no differences within the respective categories. The inferences drawn for seed storage potential hold for seed vigour potential.     

Identification of genomic regions carrying QTL for agronomic and quality traits in rye (Secale cereale) introgression libraries

Introgression libraries can be used to localize genomic regions carrying quantitative trait loci (QTL). We used this approach to detect QTL regions affecting the per se performance of agronomic and quality traits with two rye (Secale cereale L.) introgression libraries. Our objectives were to detect candidate introgression lines (pre‐ILs) that have a different per se performance than the recurrent parent and to identify the underlying QTL regions. The introgression libraries containing 40 BC₂S₃ lines each were established with marker‐assisted backcrossing from crosses of the heterozygous Iranian primitive rye accession Altevogt 14160 and the elite inbred line L2053‐N. To assess the phenotypic effect of the donor chromosome segments (DCS) the pre‐ILs were evaluated for grain yield, plant height, thousand‐kernel weight, test weight, falling number and protein content in replicated field trials at five locations in Germany over 2 years. In total, 58 significant (P < 0.05) differences between pre‐ILs and L2053‐N were observed in each introgression library. The DCS in pre‐ILs differing from the recurrent parent possess most likely the responsible QTL. Genomic regions carrying favourable QTL alleles were detected for test weight, thousand‐kernel weight and protein content. We conclude that Altevogt 14160 can not only be used to enrich the genetic variation of the restricted hybrid rye gene pools but will also allow the breeder to efficiently detect favourable QTL for marker‐assisted selection.     

Androgenetic green plants from winter rye, Secale cereale L., of diverse origin

Twenty varieties and breeders’ lines of winter rye, Secale cereale L., including Finnish, Polish, Russian, Swedish and Danish germplasm, were tested for their anther culture ability. To establish a reference point, the initial culture method was based on published results from rye anther culture. Following results from methodological studies, a modified protocol was tested on the same 19 winter rye lines. The modifications to the protocol included growth of mother plants under controlled greenhouse conditions, prolonged cold pretreatment of spikes for 3 weeks at 4°C, excision of anthers with microspores in the late uninucleate/binucleate developmental stage and induction on liquid medium supplemented with a buoyancy increasing component, Ficoll. With the modified protocol, the total production of green androgenetic plants increased nearly fivefold; it reached an average of 2.75% with the best line yielding 12.5%, while the proportion of green to albino plants increased by 50% to 25.1%. Eighteen rye lines showed green plant regeneration ability. Several genetically different winter rye lines with relatively good anther culture ability, yielding ≤ 1/% green plants per 100 anthers, were identified for the use in further methodical studies and for researching doubled haploidy in rye breeding.     

Variation of Telomeric Heterochromatin Among Inbred Lines in Diploid Rye (Secale cereale L.)

The amount of Telomeric C-heterochromatin was investigated in 20 inbred lines of rye and their open-pollinated source cultivars. In this short communication only the banding pattern of the chromosomes in the lines is presented. The inbred lines had an amount of heterochromatin similar to the source cultivars. Both groups carried some chromosomes with small telomeric C-bands. The individual source cultivars were composed of 2—4 karyotypes having different amounts of telomeric heterochromatin. Most karyotypes were also identified in the respective inbred lines. Results suggest that the in breed in i: process was not related to a reduction of telomeric C-hetrerochromatin in rye chromosomes.     

Genetical Studies of Gibberellic Acid Insensitivity in Rye (Secale cereale L.)

Genetic analysis of three semi-dwarf genotypes of rye (Secale cereale L.)—‘Moskowskij Karlik’, ‘Gülzow kurz’ and ‘R 18’, which were shown to be insensitive to applied gibberellic acid (GA₃), has been carried out by using a seedling test. It could be demonstrated that all of the three genotypes are carrying recessive alleles for GA-insensitivity. Whereas the alleles of ‘Moskowskij Karlik’ and ‘R 18’ seem to have the same locus on chromosome 5R, the GA-insensitivity of ‘Gülzow kurz’ is governed by a different gene, most probably located on chromosome 7R. The relationship between the genes (alleles) for GA-insensitivity and semi-dwarfness, including the symbolization of the Gai-genes as well as their utilization in rye breeding is discussed.     

Maternal induced haploids in rye (Secale cereale L.)

Summary An inbred line of rye named P8 was found to possess haploid plants in their diploid stock. Phenomenon of spontaneous haploidy was examined in this line. Fifty families derived from this inbred line were screened to determine their ploidy level by mitotic chromosome count taking root tips. Seven families were found to contain haploid plants. Among these seven families, plants from two families which were diploid were crossed reciprocally with the standard out breeding cultivar Conrah. As all of the tested plants of P8 were found aa allele for 6-Phosphogluconic dehydrogenase (6-PGD) isozyme, therefore, only those Conrah plants which have bb alleles for the same isozyme were used in crossing programme.F1 seedlings were screened with the same isozyme marker and out of 1741 F1 seedlings tested, 51 were found to be non-hybrid phenotype for 6-PGD enzyme. Among these, only five plants were found haploid and the rest were diploid. Haploid plants were obtained only from those crosses where P8 was female which indicates that haploids in this line was maternally induced.     

RAPD markers linked with restorer genes for the C-source of cytoplasmic male sterility in rye (Secale cereale L.)

The study was aimed at the identification of random amplified polymorphic DNA markers linked to genes controlling male sterility in rye with the C‐source of sterility‐inducing cytoplasm. Markers of male sterility were distinguished using bulk segregant analysis, carried out on the two F₂ crosses between male sterile and male fertile inbred lines. Screening of polymorphisms revealed by 1000 arbitrary 10‐mer primers allowed the detection of 10 markers in the cross between 711‐cmsC and DS2 lines and seven markers in the cross between 544‐cmsC and Ot0‐20 lines. Five markers were common for the two crosses, which allowed comparative mapping to be performed. Ten markers were mapped on the 4RL chromosome arm where two linked quantitative trait loci (QTL) for male sterility were discovered. Additional QTL of minor effect on male fertility were detected between the two linked markers provisionally assigned to the 6RS chromosome arm. The effectiveness of the marker‐assisted selection (MAS) for male‐sterile genotypes was evaluated.     

Hybridization of Thinopyrum distichum and Secale cereale

An attempt was made to determine whether the salt tolerance genes of Thinopyrum distichum would be expressed in the presence of the rye genomes and if it would be possible to improve and utilize its hybrid with rye as a salt-tolerant fodder crop. Th. distichum florets were pollinated with diploid and tetraploid rye but hybrids were obtained only with tetraploid rye. The F₁ had 28 chromosomes and expressed high levels of salt tolerance. Fertility could not be induced through colchicines treatment but the plants produced some apomictic seeds during the summer months. The F₂ had 20-22 chromosomes and retained two complete or near-complete rye genomes. The F₂ plants responded better to colchicine treatment, however, the doubled hybrids remained male sterile. In summer, one F2 plant produced many apomictic seeds with chromosome numbers ranging from 14 to 16 (primarily rye chromosomes). The mechanism that caused the preferential loss of Thinopyrum chromosomes in each apomictic cycle remains unknown. The F₃ phenotypically resembled rye, had primarily reductional male meioses and produced seemingly functional pollen, but were self-sterile.     

新疆杂草黑麦基本农艺性状分析

为了对新疆杂草黑麦（Secale cereale subsp. segetale）种质资源进一步研究利用提供依据,对58个新疆杂草黑麦居群的株高、穗长、穗宽、小穗数、有效穗数、穗粒数和千粒重等农艺性状进行了考察和分析。结果表明,58个新疆杂草黑麦居群7个农艺性状的遗传变异范围为5.1%~42.8%,材料89R66株高最高、89R23有效穗数最多、89R43小穗数最多、90R6穗粒数最多、89R34千粒重最大;相关性分析和通径分析表明,新疆杂草黑麦的穗长、穗宽对千粒重有直接或间接影响;聚类分析在欧式距离11.0处将所有材料分为4类,第Ⅰ类材料的穗粒数较多且千粒重较大,可作为黑麦和小麦遗传育种资源,第Ⅱ类和第Ⅲ类材料具有高     

Identification of seven telotrisomics of rye (Secale cereale L.)

Summary Seven monotelotrisomics emerged spontaneously from primary trisomics of rye cv. Esto. Analyses of karyotype, of chromosome pairing in meiosis and of Giemsa banding pattern were used to identify monotelotrisomics in rye as IRS, 1RL, 3RS, 4RS, 4RL, 6RS and 7RL. Vitality and fertility were better than in primary trisomics. The extra telocentrics were well transmitted through the female gamete. Transmission through the male gamete was in all cases less than trasmission through the female gamete.     

The Identification of a Gibberellic-Acid-Insensitive Gene in Secale cereale*

Among 16 dwarfing genes identified in wheat (Triticum aestiuvm L. em Thell.), four are known to be associated with insensitivity to the externally-supplied growth hormone gibberellin (GA). Rht1 and Rht2 (Reduced height 1 and 2, respectively) have been the most extensively used, because of their positive effect on yield. To increase the germplasm pool for dwarfism, a spring rye (Secale cereale) population (UC-90, CI-174) was selected because it contains high variability and any useful genes would benefit triticale and wheat as well. Seedlings of the CI-174 rye population were treated with 50 ppm of GA to identify any insensitive types. GA-insensitive and -sensitive seedlings were identified and, after three generations of selfing, GA-insensitive and -sensitive lines were fixed. Rye insensitive was crossed to a sensitive wheat and to rye and, reciprocally, insensitive wheat was crossed to sensitive rye. The results indicated that a GA-insensitivity dwarfism system similar to that originally found in wheat also operates in rye and appears to be under simple inheritance. Rye GA-insensitivity was expressed in triticale. Therefore, it is possible to transfer this new source of insensitivity and dwarfism into triticale and wheat.     

Differences in Mycorrhizal Colonization of Rye (Secale cereale L.) Grown in Conventional or Organic (Biological-dynamic) Farming Systems

The colonization of rye ( Secale cereale L.) roots with vesicular-arbuscular (VA) mycorrhizal fungi was investigated at two sites, cultivated using conventional or biological-dynamic farming methods. The VAM infection rate and infected root length were significantly higher at the biologically-dynamic cultivated site. It is suggested that these differences are due to several factors, such as the use of fertilizers and agro-chemicals, and the influence of crop rotation.     

Genetic mapping of quantitative trait loci in rye (Secale cereale L.)

Using the marker information of 275 F₂ plants quantitative traits determining morphological and yield characters were studied analyzing F₃progenies grown in four different experiments at three sites. The map constructed contains 113 markers including the major dwarfing gene Ddw1 with an average distance of about 10 cM between adjacent markers. Of the 21 QTLs detected ten were found to map on chromosome 5RL in the region of Ddw1. Beside the expected effects on plant height and peduncle length that are most probably due to the presence of the major dwarfing gene, additional effects on yield characters and flowering time were discovered in that region which may be caused by pleiotropic effects of Ddw1. An additional supposed gene cluster consisting of four QTLs controlling flowering time and yield components was discovered in the centromere region of chromosome 2R. Further loci are distributed on chromosomes 1R (1), 4R (1) 6R (3) and 7R (1). The map positions of the quantitative trait loci detected in rye are discussed in relation to major genes or QTLs determining agronomically important traits in other cereals. This revised version was published online in July 2006 with corrections to the Cover Date.     

生物素标记的重复DNA序列与黑麦染色体的原位杂交

本研究以两个黑麦重复ＤＮＡ序列ｐＳｃ１１９．１和ｐＳｃ１１９．２作探针进行原位杂交，研究其在小麦和黑麦杂色体上的分布及在检测黑麦染色质中的应用。实验结果表明：ｐＳｃ１１９．１分布于所有黑麦染色体的长短臂上，但在小麦染色体上几乎检测不到杂交信号，证明ｐＳｃ１１９．１对黑麦染色体具有专化性。进一步用该探针与小麦品种“Ａｍｉｇｏ”的体细胞染色体进行原位杂交，可明显检测出其中一对含ＩＲＳ的染色体。ｐＳｃ１     

黑麦不同叶位叶片、叶鞘叶肉细胞形态及其功能的研究

以田间生长的两个黑麦品种为材料，对各叶位叶片、叶鞘的叶肉细胞形态进行了离析观测。黑麦各叶片叶肉细胞形态不一，从1环到10余环。冬前所生叶片叶肉细胞的形态各叶位间无明显的变化规律；春季伸长节间的叶片，随叶位的上升多环细胞所占比例渐增，旗叶尤其明显。越冬前后长出的叶片叶肉细胞的长、宽均较大，以前和此后伸出     

Evidence for Monotelodisomics in Rye (Secale cereale L.)

Monotelodisomics of chromosome arms 2RL and 6RL were observed in progenies of rye trisomics. The monotelodisomic of chromosome arm 6RL (2n = 13 + 6RL) is vital and is well transmitted through the pollen. In the progeny of monotelodisomic 2RL. (2n = 13 + 2RL) no monotelodisomic but one monotelotrisomic of chromosome arm 2RS (2n = 14 + 2RS), one trisomic with an aberrant chromosome consisting (if chromosome arm IRS and a part of chromosome arm 2RL (2n = 14 + 2RSL) and one double telotrisomic of chromosome 2R (2n = 13 + 2RS + 2RL) have been identified.     

节节麦和黑麦杂种F1及双二倍体中基因组变异分析

人工合成的双二倍体在遗传和植物育种中有重要作用。为探讨远缘杂交后代双二倍体育性提高及其细胞学稳定的分子机制,利用ALFP、MASP技术对节节麦-黑麦杂种及其双二倍体S₁~S₄代的基因组变异进行了分析。该双二倍的S₁~S₄代体细胞染色体数2n = 28的植株的比例从57.1%提高到92.5%,2n = 28的植株的花粉母细胞减数分裂中期二价体平均数目从11.7提高到12.25,平均结实率从24.5%提高到51.3%。利用两套分别扩增重复序列和单拷贝序列的酶切引物组合EcoR I/Mse I (E-M)、Pst I/Mse I (P-M)对节节麦–黑麦杂种F₁和双二倍体S₁~S₄代扩增表明,基因组序列变异主要发生于F₁代,且以序列消除为主。E-M和P-M引物扩增带中, 节节麦基因组在F₁代的序列消除带数占各代总消失带数的70.00%和52.95%,而在黑麦基因组为96.88%和81.64%。MSAP分析表明节节麦和黑麦杂种和加倍能够导致节节麦和黑麦基因组序列甲基化状态改变,以甲基化为主,仅发生在F₁和S₁代。在S₂~S₄代中没有检测到甲基化变异。     

Stability of RAPD markers for determining cultivar specific DNA profiles in rye (Secale cereale L.)

Summary Cultivar specific DNA profiles in rye were revealed by polymerase chain reaction (PCR) using randomly amplified polymorphic DNA (RAPD) sequences. Ten base primers were used for the amplification of genomic DNA of rye cultivars by PCR. RAPD analysis was found to be reproducible among samples between PCR runs. When amplification profiles of different rye cultivars were compared using various primers, the overall profiles were cultivar specific. However, not all primers revealed polymorphisms. These primers appear to amplify conserved sequences in all rye cultivars. Intracultivar studies were conducted on two of the cultivars. In the cultivar Imperial, no polymorphisms were observed among ten plants analyzed with five primers. In the cultivar Balboa, polymorphisms were observed among fifty plants with four of the ten primers analyzed. Despite the small amount of intracultivar variability, RAPD analysis has the potential to be a rapid and reliable method of cultivar identification in this outcrossing species.