Submitted to: Association for the Advancement of Industrial Crops Conference
Publication Type: Abstract only
Publication Acceptance Date: 10/10/2003
Publication Date: 10/15/2003
Citation: DIERIG, D.A., TOMASI, P., DAHLQUIST, G.H., DAWSON, H. 2003. MEASUREMENTS OF LESQUERELLA INTERSPECIFIC HYBRIDS AND PARENTS. ASSOCIATION FOR THE ADVANCEMENT OF INDUSTRIAL CROPS CONFERENCE. P. 39. Interpretive Summary:
Technical Abstract: Hydroxy fatty acids (HFA) are the major components of the seed oil profile of Lesquerella species. One of three different HFA predominates in the seed oils of species of plants from this genus. Lesquerolic acid (C20:1OH) is the primary HFA found in species from the western and southwestern U.S. The range of quantity varies depending on the species. Lesquerella fendleri is being developed for commercialization because of its productivity and adaptability to farm management practices. However, the range of natural variability for this trait is limited in this species. Lesquerolic acid accounts for only around 60% of the total fatty acids compared with other species that have up to 85% of this acid, but they lack other important yield-related traits. Our objective has been to introgress the trait for high HFA content into L. fendleri from other species. We measured various characters to follow the pattern of inheritance between crosses. L. pallida and L. lindheimeri both have high HFA amounts and were used along with L. fendleri, crossed among each other and also self-pollinated. It was necessary to double the chromosome number of plants using colchicine to overcome sterility and obtain seed from hybrids. Ovule culture was used in cases when seed did not develop to produce plants of the next generation. The traits measured were petal length, number of ovules per silique, number of seeds per silique, and weight of 1000 seeds. Fatty acid compositions were also measured, and flower color and fertility were scored. Parent plants were diploids, n = 6, and hybrids were amphidiploids, n=4x=24. L. pallida has a white flower color and the other two species have yellow flowers. Petal length was smaller on L. pallida and L. lindheimeri than L. fendleri. The 1000 seed weights and the number of ovules per silique were different among all three species. L. lindheimeri had the highest seed weight and lowest ovules per silique. L. fendleri had the lowest seed weight and highest number of seeds per silique. Seeds per silique counts indicated that autofertility occurred in L. pallida but not in the other two species. HFA oil content of L. fendleri seeds was 50.5% compared with 84.1% for L. lindheimeri. F1 hybrids indicated maternal influenece over flower color and petal length when reciprocal crosses weres examined. White flowers were expressed on hybrids when the female parent had yellow flowers (L. fendleri). Petals were smaller in this case than the reciprocal cross but still intermediate of both parents. Pale yellow flowers were expressed and petals were longer than both parents when the female parent had white flowers (L. pallida). These measurements will help predict the value of the different types of interspecific crosses for breeding. Segregation for various yield-related traits should allow selection for favorable improvements in the HFA trait and seed yield.