Identification of sterility-inducing cytoplasms in rye using the plasmotype–genotype interaction test and newly developed SCAR markers

Abstract

A series of 25 rye (Secale cereale L.) inbred lines was tested with respect to three mitochondrial sequence-characterized amplified region (SCAR) polymorphisms. The analysis revealed a close association between the marker-determined mitotypes and plasmotypes (cytoplasm types known from breeding data) represented by the inbreds. The mitochondrial markers also confirmed normal (N-) cytoplasmic character of three wild rye species: Secale montanum, S. vavilovii and S. kuprijanovii. For 186 plants from open-pollinated cultivars of Turkish and South American origin, cytoplasm identification was performed with the use of crossing with double non-restoring tester. In 77 plants the normal (N) cytoplasm was detected, and for 63 of these the PCR analysis was performed producing results which were consistent with the genetic data based on testcrossing and phenotype assessment. The mitochondrial markers also confirmed a presence of sterility-inducing cytoplasm in the remaining 109 plants. Moreover, the markers allowed for differentiation between Pampa (P-) and Vavilovii (V-) cytoplasmic individuals. For 60 plants the latter results were verified using crosses with a line maintaining P-cytoplasmic sterility and acting as a restorer of the V-cytoplasm. For two of these plants contradicting results were produced with the applied methods of cytoplasm identification and the basis of this discrepancy is discussed. Regardless of the identification method, widespread occurrence of a sterility-inducing cytoplasm was revealed, especially in South American populations.

Determining the plasmotypic structure of rye populations by SCAR markers

“…The discovery of effective restorer genes for CMS-P in rye originating from South America (Geiger and Miedaner 1996;Miedaner et al 1997) is in agreement with the CMS-P cytoplasm occurring in different populations from this region, as reported previously (£apiñski and Stoja³owski 2003;Stoja³owski et al 2006) and confirmed in this study.…”

“…by Kobylyanskii (1971Kobylyanskii ( ), £apiñski (1972, Madej (1975), and Adolf and Winkel (1985). It is known that the CMS-V cytoplasm frequently occurs in European rye breeding materials, while the CMS-P type was identified mainly in South American populations (£apiñski and Stoja³owski 2003;Stoja³owski et al 2006). Knowledge of the cytoplasmic structure of rye cultivars is important, since the presence of sterilizing cytoplasm forces a natural selection eliminating non-restorer alleles from populations.…”

“…Knowledge of the cytoplasmic structure of rye cultivars is important, since the presence of sterilizing cytoplasm forces a natural selection eliminating non-restorer alleles from populations. The cytoplasm type identification can be done by a conventional plasmotype-genotype interaction (PGI) test or by recently developed SCAR markers (Stoja³owski et al 2006). The second method enables screening of a large population at a low cost.…”

“…DNA was extracted from young leaves with the single-step method described by Thomson and Henry (1995). PCR conditions and primer sequences are described in Stoja³owski et al (2006). The only modification concerns a doubling of the annealing time to 90 seconds for marker nad2, substantially improving the PCR product amplification.…”

Hybrid breeding boosted molecular genetics in rye

“…Митохондриальные маркеры также подтвердили наличие индуцирующей сте-рильность цитоплазмы в остальных 109 растениях. Кроме того, с помощью маркеров можно было различить расте-ния, имеющие Р-или V-тип цитоплазмы, а также удалось выявить широкую распространенность индуцирующей стерильность цитоплазмы, особенно в южноамериканских популяциях (Stojałowski et al, 2006).…”