International Database for Barley Genes and Barley Genetic Stocks

BGS 317, Reaction to DDT 1, ddt1

BGN  26:266
Stock number: BGS 317
Locus name: Reaction to DDT 1
Locus symbol: ddt1

Previous nomenclature and gene symbolization:

Resistance to DDT = ddt (4).


Monofactorial recessive (2, 7).
Located in chromosome 5HS (3, 4); ddt1.a is about 3.0 cM distal from the breakpoint in translocation stock T2-7a (5).


The recessive allele, ddt1.a, confers resistance to the insecticide DDT. After spraying seedlings at the 2- to 3-leaf stage with a concentration of 1 part per 500 in water, susceptible plants show severe chlorosis followed by yellowing and death about 10 days. A second application about 7 days after the first will insure complete kill of susceptible seedlings. The DDT solution affects only the leaf it comes in contact with it; thus, plants can be classified for reaction to DDT about anthesis by dipping a single leaf into the DDT solution. The part of the leaf blade covered by solution on susceptible plants will turn yellow and die, whereas it remains green on resistant plants (1, 2, 7). The frequency DDT susceptibility in collections is about 10%, nearly 40% in two-rowed entries and 1% in six-rowed ones (7).
No images

Origin of mutant:

Spontaneous occurrence in several commercial cultivars (2, 6, 7).

Mutational events:

ddt1.a (GSHO 331) in Spartan (CIho 5027) (7).

Mutant used for description and seed stocks:

ddt1.a (GSHO 331) in Spartan.


1. Griffiths, D.J., and J.D. Hayes. 1959. Rapid tests for varietal purity. Agricultural Merchant 39 (No. 9):74-76.
2. Hayes, J.D. 1959. Varietal resistance to spray damage in barley. Nature, London 183:551-552.
3. Hayes, J.D., and M.S. Rana. 1966. Investigations on genetic resistance to chemicals in spring barley. Welsh Plant Breeding Station, Aberystwyth, Report for 1965:47-48.
4. Hockett, E.A., and R.F. Eslick. 1969. Genetic male-sterile genes useful in hybrid seed production. p. 298-307. In R.A. Nilan (ed.) Barley Genet. II. Proc. Second Int. Barley Genet. Symp., Pullman, WA, 1969. Washington State Univ. Press, Pullman.
5. Ramage, R.T., M. Paluska, and G.A. Wiebe. 1973. Genetics and cytology of the translocation T2-7a. Barley Genet. Newsl. 3:47-49.
6. Wiebe, G.A. 1960. A proposal for hybrid barley. Agron. J. 52:181-182.
7. Wiebe, G.A., and J.D. Hayes. 1960. The role of genetics in the use of agricultural chemicals. Agron. J. 52:685-686.


R.T. Ramage. 1984. Barley Genet. Newsl. 14:95.


J.D. Franckowiak. 1997. Barley Genet. Newsl. 26:266.