Publications

genetic differentiation during speciation in the helianthus debilis complex.		1983	28556004
the sensitizing capacity of compositae plants. vi. guinea pig sensitization experiments with ornamental plants and weeds using different methods.	experimental studies in guinea pigs using ether extracts of 20 different species of the compositae plant family were carried out with the open epicutaneous method (oet) and the guinea pig maximization test (gpmt). the results demonstrate that cnicus benedictus (blessed thistle), chrysanthemum leucanthemum (marguerite, ox-eye daisy) and helianthus debilis (dwarf sunflower) are strong sensitizers while helenium amarum (bitterweed), gaillardia amblyodon (blanket flower), artemisia ludoviciana (prai ...	1985	3970585
helianthus annuus ssp. texanus has chloroplast dna and nuclear ribosomal rna genes of helianthus debilis ssp. cucumerifolius.	heiser [heiser, c. b. (1951) evolution 5, 42-51] hypothesized that helianthus annuus ssp. texanus was derived by the introduction of h. annuus into texas and subsequent introgression of genes from helianthus debilis ssp. cucumerifolius into h. annuus. although often considered to be one of the best cases of introgression in plants, alternative hypotheses to introgression, such as convergence or the joint retention of the ancestral condition, could not be ruled out in the original study. to test ...	1990	11607056
adaptive introgression of herbivore resistance traits in the weedy sunflower helianthus annuus.	the role of hybridization in adaptive evolution is contentious. while many cases of adaptive trait introgression have been proposed, the relevant traits have rarely been identified, resulting in a lack of clear examples of this process. here, we examine a purported case of adaptive introgression in which the annual sunflower helianthus annuus annuus has captured alleles from a congener (helianthus debilis) to form a stabilized hybrid, helianthus annuus texanus. we tested the hypotheses that herb ...	2006	16649157
sargassum as a natural solution to enhance dune plant growth.	many beach management practices focus on creating an attractive environment for tourists, but can detrimentally affect long-term dune integrity. one such practice is mechanical beach raking in which the wrack line is removed from the beach front. in texas, sargassum fluitans and natans, types of brown alga, are the main components of wrack and may provide a subsidy to the ecosystem. in this study, we used greenhouse studies to test the hypothesis that the addition of sargassum can increase soil ...	2010	20859628
adaptive introgression of abiotic tolerance traits in the sunflower helianthus annuus.	adaptive trait introgression is increasingly recognized as common. however, it is unclear whether adaptive genetic exchanges typically affect only a single trait, or instead affect multiple aspects of the phenotype. here, we examine introgression of abiotic tolerance traits between two hybridizing north american sunflower species, helianthus annuus and helianthus debilis. in two common gardens in the hybrid range, we measured 10 ecophysiological, phenological, and architectural traits for pare ...	2010	20345635
genome scan of hybridizing sunflowers from texas (helianthus annuus and h. debilis) reveals asymmetric patterns of introgression and small islands of genomic differentiation.	although the sexual transfer of genetic material between species (i.e. introgression) has been documented in many groups of plants and animals, genome-wide patterns of introgression are poorly understood. is most of the genome permeable to interspecific gene flow, or is introgression typically restricted to a handful of genomic regions? here, we assess the genomic extent and direction of introgression between three sunflowers from the south-central usa: the common sunflower, helianthus annuus ss ...	2010	20355258
sunflower resistance to broomrape (orobanche cumana) is controlled by specific qtls for different parasitism stages.	orobanche cumana (sunflower broomrape) is an obligatory and non-photosynthetic root parasitic plant that specifically infects the sunflower. it is located in europe and in asia, where it can cause yield losses of over 80%. more aggressive races have evolved, mainly around the black sea, and broomrape can rapidly spread to new areas. breeding for resistance seems to be the most efficient and sustainable approach to control broomrape infestation. in our study, we used a population of 101 recombina ...	2016	27242810