Plant breeding for organic and sustainable, low-input agriculture

Morphological parameters used in the characterization of rye recombinant inbred lines for
nutrient deficiency in medium
Miłosz Smolik, Rzepka-Plevneš Danuta, Kurek Jadwiga
Department of Horticultural Plant Breeding, Agricultural University of Szczecin, Poland
Selection using in vitro cultures is useful in identifying genotypes tolerant to biotic and abiotic
stresses at seedling and cellular stages (Dahleen et al. 1991). According to Rzepka-Plevneš
(1996) selection of cereals for tolerance to nutrient deficiency at the seedlings stage is possible,
when length of primary roots and number of secondary roots is used as a selection criterion. The
aim of the present studies was to determine the reaction of RILs to the nutritional (N and K)
stress in the medium and select the lines (RILs) of tolerance of extreme difference to the caused
stress. The 139 RILs (F5) were derived from generation F2 of the hybrid (153/79-1 x Ot 1-3)
obtained from the crossing of two rye inbred lines: high tolerant - 153/79-1 - was derived from
the hybrid (544-7-1-5 x 542-9-1-11) and low tolerant to nutrient deficiency in the medium - Ot 1-
3 which was derived from old swedish variety Otello. The tolerance of parental rye inbred lines
and RILs was assessed by means of the in vitro test (Rzepka-Plevneš et al. 1997). The biometric
measurements of seedlings were made in which the height of coleoptile, the length and number
of roots were estimated. These studies, like the in vitro test itself, were carried out using both the
seedlings exposed to the stress and the control seedlings. The RILs seedlings which did not differ
significantly as regards the estimated morphometrical parameters were the lines tolerating the
nutritional stress. The lines in which this reaction was significantly different were regarded as
non-tolerant to nutrient deficiency.
The results of the studies showed that within the range of the examined inbred lines there is large
variability both with regard to the height of seedlings, the number and length of roots. Rye
seedlings tested on the medium with deficit in N and K formed on average longer coleoptiles but
shorter germ roots compared to the control seedlings. In regard to the number of roots no
significant differences in relation to the controls were observed. By means of the described
method Rzepka-Plevneš et al. (1999) selected forms of both rye and triticale characterised by
high tolerance to nutrient deficiency in the medium. Their agronomic features described in the
experiments did not differ significantly in respect of most traits compared to the control ones.
Hence, in this study this test was used to examine the reactions of the RIL lines to nutrient
deficiency stress. The described RIL lines can be used in organic breeding as components for
crossing. Moreover, they are a valuable source of genes of tolerance to abiotic stress. They serve
for maintenance of biodiversity and can constitute material for physiological, biochemical and
molecular studies.
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