Hayes and Garber - Cucurbit Breeding

COTTON AND SORGHUM 179
to a sweet stalk. The second generation of the cross segregated
as a monohybrid. Graham (1916) of India, studied the inheritance
of length of glume and color of seed-coats in some
natural and artificial crosses. Long and short glumes behaved as
a simple Mendelian pair with the former dominant. In the inheritance
of color of grain a series of multiple allelomorphs are
involved. Red may be allelomorphic to yellow or white and likewise
yellow may be allelomorphic to white. The usual color
dominance is shown. Sometimes when yellow and white are
crossed the heterozygote is red and in the next generation segregates
with a 9 red : 3 yellow : 4 white ratio. Graham suggests
that certain of the white seeds are undeveloped reds requiring the
presence of yellow -to cause the development of the red color.
Some Results of Selection. Sorghum improvement by breeding
has been accomplished principally through selection. Dwarf
forms have occurred in most varieties and have furnished material
for the production of such varieties as Dwarf Milo, Dwarf Kafir,
etc. These varieties have been isolated through selection. Sugar
content has also been improved. Failyer and Willard conducted
selection experiments at the Kansas Station from 1884 to 1903.
During that time they increased the sugar content of the Orange
variety from 12. 62 to 16. 10 per cent. At the Delaware Agricultural
Experiment Station even more striking results were obtained
(Neale, 1901). The variety Amber, from which selections were
made, contained on the average 11 percent, sugar with a purity
of 65. One of the selections made from it had a sugar content
of 18.2 per cent, with a purity of 81. Dillman (1916),
of the
United States Department of Agriculture, made several selections
from Minnesota Amber with the object of securing an early
One of the selections, Dakota
maturing, drought resistant strain.
Amber, has proved valuable.
It is more dwarf in habit of growth
than Minnesota Amber and matures 15 days earlier.
It produces
excellent forage as well as abundant seed. Early dwarf forms,
as a rule, are more drought resistant than late ones.
Method of Breeding Sorghum. Sorghum belongs to the
naturally self-fertilized group of farm crops and the essential
features of breeding it are the same as for the group. However,
sorghum is more frequently cross-fertilized than most of the
other naturally selfed crops and for this reason it is necessary
to resort to bagging the panicles, where different lines are grown
in close proximity to one another. That bagging does not inhibit