Safflower in California - University of California Cooperative Extension

Male sterility
A very thin-hulled mutant of safflower was discovered by Rubis (1962) which was governed by the recessive
gene th. The mutant trait was associated with weak stems and much-delayed pollen release. It was believed
that delayed pollen release would serve as a form of structural male sterility. Efforts by plant breeders to develop
genotypes to develop usable structurally male-sterile genotypes were unsuccessful. The delay in, and amount of,
pollen release was unpredictable, so there could be an unpredictable amount of thin-hulled types, which were low
yielding in hybrid varieties. Efforts were made through selection to separate the thin-hulled trait from weak stems,
delayed pollen release, and low yield, but without success.
Ebert and Knowles (1968) found that the genotype thth for thin hulls had one primary effect: it reduced or
prevented secondary wall formation in the cells of “fibrous” tissues. This resulted in thin hulls of the seeds, weak
stems and branches, and delayed dehiscence of the anthers—th was a gene with a pleiotropic effect. The absence
of secondary wall formation in the anthers, which is involved in dehiscence, resulted in a collapse of the walls in a
disorganized manner, resulting in failure or delay in the release of pollen.
Heaton and Knowles (1982) reported the discovery of genetic male sterility in accession PI 263914 from
Afghanistan that had been treated with colchicine. It was governed by a single recessive gene ms. Two germplasm
releases were made, UC-148 with orange flowers, developed from the original mutant, and UC-149 with white
flowers developed from a cross of UC-148 with PI 340088, an introduction from Turkey (Heaton and Knowles
1980).
Genetic male sterility was not acceptable for commercial use in the US because of labor costs necessary to remove
fertile (Msms) genotypes from the female parent (a 1:1 mixture of Msms and msms). In India, however, it is
being used by one company which is experimenting with a female parent that has appressed branches (apap) and
is spineless—this makes removal of the male-fertile types much easier. If the male parent has spreading branches
and spines, the F1 hybrid will be the same.
A
16
B
The first step in processing safflower for oil in Egypt was
cracking seed with a stone grinder sufficiently to loosen the
hulls. Screens were used to separate hulls from seed. The
second step was grinding of the seed with a rolling round
stone, pictured in A (Large roller used to crush oil seeds.
Assiut, Upper Egypt. June 19, 1958). Finally this ground seed
was placed in tight flat straw baskets shaped like a beret pictured
in B (Flat basket made of reeds. Assiut, Upper Egypt.
June 19, 1958). Several filled baskets were stacked one on top
of the other and pressure applied to the top with either a
hand-operated screw press or a heavy wooden lever. About
125 kilos of seed gave 20 kilos of oil. (Text and photos from
Knowles 1959.)