II. 10. New trisomics in barley.

A. Shahla and T. Tsuchiya, Department of Agronomy, Colorado State University, Fort Collins, Colorado, 80523, U.S.A.

Four new trisomics have been obtained for various chromosomes of barley.

1 - Acrotrisomic 3L^3B.

This trisomic was obtained in an F2 population derived from a cross between Triplo 3L and a_c. Chromosomes stained by Giemsa N-banding technique showed that the extra acrocentric chromosome carried the entire long arm and a small proximal segment of the short arm. The pedigree of this acrotrisomic is as follows:

Figure 1: Telo 83-11-9

2 - Acrotrisomic 6S^6LB

One plant 2n = 14 + 1 telo 6S + 1 acro 6S^6LB was found in stock seed of Triplo 6S (Telo 85-1-20) which was an offspring of Telo 83-67-17. The extra acrocentric chromosome is similar to the previously found acrocentric chromosome 6S^6LA (Shim and Tsuchiya, 1983) which consists of a deficient short arm and a small segment of the long arm. The new acrocentric chromosome 6S^6LB seems to have more deficiency in the short arm but the segment of the long arm is slightly longer than the previous aerocentric chromosome.

3 - Acrotrisomic 7S^7B.

One diacrotrisomic plant was obtained in an F2 population derived from a cross between Triplo 6S and ea7. Based on chromosome study the extra acrocentric chromosomes seems to be acrotrisomic 7S^7L. The pedigree of this plant is as follows:

Figure 2: Telo 83-67-21

One acrotrisomic line for chromosome 7(acro 7S^7L) has already been reported (Furst and Tsuchiya, 1983), this is the second acrotrisomic line for chromosome 7.

4 - Trisomic for a centric fragment of chromosome 6.

This trisomic was found in an acrotrisomic stock, Triplo 6S^6L(Telo 84-22-26) which was an offspring of Telo 84-6-1. In the somatic cells the trisomic showed a small metacentric fragment. It seemed acro 6S^6L lost its satellite and the remaining segment of the short and long arm formed the centric fragment.
 

References:

Furst, E, and T. Tsuchiya. 1983. New telosomic and acrosomic trisomics in barley. BGN 12:47-48.

Shim, J.W. and T. Tsuchiya, 1983. Two new types of trisomics in barley. BGN 13:70-71.
 

BGN 15 toc
BGN Main Index