103(4)_str48

ISSN 1392-3196 / e-ISSN 2335-8947
Zemdirbyste-Agriculture, vol. 103, No. 4 (2016), p. 377–384
DOI  10.13080/z-a.2016.103.048

Production of Trifolium pratense L. and T. hybridum L. tetraploid populations and assessment of their agrobiological characteristics

Giedrė DABKEVIČIENĖ, Gražina STATKEVIČIŪTĖ, Jovita MIKALIŪNIENĖ,
Eglė NORKEVIČIENĖ, Vilma KEMEŠYTĖ

Abstract

The current study was set out to establish the efficacy of different mitosis inhibitors (colchicine, amiprophos-methyl, trifluralin and oryzalin) used in the production of red clover (Trifolium pratense L.) and alsike clover (Trifolium hybridum L.) polyploids and to assess the agrobiological traits of tetraploid populations. Four cultivars and five wild populations of T. pratense, one cultivar and three wild populations of T. hybridum were used for polyploidization. The effect of conventional soaking of germinating seeds in a colchicine solution was compared with that of colchicine treatment of embryos in an in vitro culture. Colchicine treatment of T. pratense embryos resulted in 3.3 times higher production of tetraploids (teraploid yield 55.0%) compared with colchicine treatment of seedlings, and the production of chimeric plants was 1.9 times lower.

The different mitosis inhibitors were characterised by a diverse polyploidization effect. Tetraploid yield depended not only on the mitosis inhibitor used but also on the plant species. Treatment of T. pratense embryos with colchicine, amiprophos-methyl and oryzalin yielded similar results in terms of tetraploid production (31.3–40.7%) and chimeras (14.3–22.4%). The concentration of trifluralin used for the production of T. pratense tetraploids was ineffective. Colchicine solution was more efficient for the development of T. hybridum tetraploids whose yield was 2.5 times as high as that obtained having treated the embryos with amiprophos-methyl.

Induced tetraploid populations were compared to reference cultivars in field trials. The two T. pratense populations ‘Radviliai 4n’ and ‘Arimaičiai 4n’ stood out in this respect – their plants accumulated higher dry matter contents, produced more inflorescences than those of the reference cultivar and exhibited prolific seed yield capacity. In relation to the agrobiological traits, the tetraploid populations of T. hybridum did not surpass the reference cultivar.

Key words: agrobiological characteristics, mitosis inhibitor, tetraploids, Trifolium hybridum, Trifolium pratense.

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