Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Plant Science

First Advisor

Charles L. Lay


The USSR is the world leader in production of sunflower seeds harvesting about 4 to 4.5 million hectares per year with production remaining fairly stable since 1960. The US and Argentina rank second and third having planted about 1.6 and 1.3 million hectares during 1981 respectively. Spain, China, Romania, Bulgaria, Australia, and Canada follow in importance. The total amount of land devoted to sunflower production in the world increased from 8.4 million hectares in the 1960's to more than 11.6 million in 1981. Sunflower became a commercial crop· in the US during the late 1960's. Production during the 1970's increased from a few thousand to 2.1 metric tons due to the establishment of markets in Europe and also the development of hybrids, which were higher in yield and oil content. Sunflower is commercially important because it produces more oil per unit land than any other crop in many areas. The crude mea1 obtained after removal of the oi1 has a protein content of 38-40%, making it a valuable protein supplement for poultry, sheep, swine, and cattle. The hulls and heads which remain after the seed is removed can be processed to yield pectin. Some large seed is used whole and roasted seed much like peanuts, whereas some seed is dehull ed and the kerne1s so1d as confectionary "nuts". Smaller whole seed is used in rations for pet birds and small animals, as well as in home feeders for wild birds. Breeding programs should be based on sound genetic principles. Estimates of genetic variability" and heritability type of gene action, and the number of genes associated with a trait provide useful guidelines to determine the value of source populations and appropriate procedures to use in a breeding program. Genetic variation of characters associated with plant growth, morphological or physiological differences may serve as a basis for development of inbred lines and hybrids with improved agronomic traits. Variability of traits such as plant height, flowering, and maturity can be particularly useful because it allows for development of types adapted to an array of environments and agronomic regions. Plant height is an important characteristic in sunflower production. Yields of tall hybrids can be reduced due to lodging. Lodging as high as 80% was observed in a test of 56 hybrids planted at White, South Dakota, in 1983, emphasizing the importance of short hybrids. Early hybrids can also overcome yield losses caused by flowering during hot dry weather and early frost. Variation among other traits; such as leaf number and internode length, seems to have less apparent value. This research was conducted to study the mode of inheritance of plant height, leaf number, internode length, flowering, and their relationship in crosses of two short inbred lines of sunflower selected from PI 386323 and PI 386316 with a number of inbred lines commonly used in production of sunflower hybrids.

Library of Congress Subject Headings

Sunflowers -- Breeding
Sunflowers -- Genetics
Inheritance of acquired characters.



Number of Pages



South Dakota State University


No Copyright - United State