Inheritance of High Anther Culture Response in Hexaploid Wheat, Triticum aestivum L. var. Svilena

R. SCHLEGEL, I. BELCHEV, K. KOSTOV¹ and M. ATANASSOVA

Institute of Wheat and Sunflower "Dobroudja", BG-9520 General Toshevo, Bulgaria
¹Corresponding author: tel. 359(058) 274 54; fax: (05731) 44 48; E-mail: iws@netplusdb.bg

Abstract

SCHLEGEL, R., I. BELCHEV, K. KOSTOV and M. ATANASSOVA, 2000. Inheritance of high anther culture response in hexaploid wheat, Triticum aestivum L. var. Svilena. Bulg. J. Agric. Sci., 6: 261-270

A screening for anther culture response, i.e. callus induction (CI), green plantlet regeneration (GP) and albino plant appearance (AP), among an European collection of 116 winter wheat varieties grown up in the field (Belchev, 1995, Annl. Rep.) revealed a limited range of variation. However, a Bulgarian cultivar Svilena was detected showing in average in several experiments a high callus induction rate (332 %), green plantlet regeneration (116.7 %) and comparably low albino portion (16 %). It was a reason to be chosen for a cross with a very low responding genotype (the Bulgarian cultivar Pliska; (CI = 0.50 %, GP = 0 %, AP = 0 %) in order to study the inheritance of those characters in Svilena. As for all wheat material tested before there was a strong correlation between CI<>GP<>AP (r = +0.94** and +0.65** ). Almost the same correlation coefficients could be calculated for the F₂ segregants (r = +0.83** and r = +0.74**). In independent studies, between varieties, within the variety Svilena (r = +0.80** and r = +0.68**) and between segregants, the same tendency as well as the same level of correlation was obvious. Even albino production was significantly positive correlated with callus induction (r = +0.70**, r = +0.95**, and r = +0.90**, respectively). Based on those correlation data the 'callus induction' was supposed as the primary characteristic giving rise to green plantlet regeneration and albino production. Therefore, it was considered for the genetic analysis.
This study was focused mainly on the F₂ population. Based on the result of F₁ population the value of CI, GP, and AP is much lower than the midparents value.
The F₂ study of the cross Pliska x Svilena pointed to a digenic inheritance, i.e. at least two loci are involved in the determination of callus induction response and/or non-response. The variety 'Pliska ' is supposed as a common non-responding genotype. It shows dominant gene expression. Its gene constitution is assigned Nc1Nc1 Nc2Nc2, while Svilena can be designated as double-recessive genotype nc1nc1 nc2nc2 with high callus induction potential.

Key words: wheat, anther culture, callus formation, green plantlet regeneration, digenic inheritance