Abstract
Cleome hasslerana Chod., a cross-pollinated species, has 5 corolla colors: violet, lilac, red, pink, and white. F1 and F2 progenies produced from crosses among the cultivars Helen Campbell Snow Crown, Cherry Queen, Pink Queen, and Violet Queen indicate that 3 loci with 2 alleles per locus control flower color. The allele W, for colored corolla, is dominant to w, for white corolla; R, for violet color, is dominant to r for red; and I, for dilute flower color, is dominant to i, determining intense flower color.
. Bonin for similar services at Woflskill Experimental Orchard. This research used materials generated as part of a pistachio genetics and improvement program with cooperators D.E. Parfitt, C.T. Chao, L. Ferguson, C. Kallsen, and J. Maranto. The cost of
extended shelf life that reduce postharvest losses could increase production efficiency by reducing the frequency of product replacement in the marketplace. This is often difficult to achieve because there are few reports on the genetics of postharvest
.R. Michelmore, R.W. 1988 The genetics of corky root resistance in lettuce Phytopathology 78 1145 1150 Gurung, S. Short, D.P.G. Atallah, Z.K. Subbarao, K.V. 2014 Clonal expansion of Verticillium dahliae in lettuce Phytopathology 104 641 649 Hayes, R.J. Vallad
to lettuce ( Lactuca sativa L.) genotyping Euphytica 144 225 235 10.1007/s10681-005-6431-1 Jørgensen, J.H. 1994 Genetics of powdery mildew resistance in barley Crit. Rev. Plant Sci. 13 97 119 10.1080/07352689409701910 Kloos, W.E. George, C.G. Sorge
Strawberry flowering habit can be classified as either day-neutral (DN) or short-day (SD), depending on whether plants are insensitive or sensitive to photoperiod, respectively. Short-day (SD) cultivars produce mature fruit for just a few weeks in early summer. New floral initiation does not commence until triggered by the combination of short daylength and low temperature in the fall. Day-neutral (DN) cultivars do not require particular daylength conditions to initiate flowering, and so continue to produce flowers and mature fruit into late summer and early fall. We are using a map-based approach to characterize the genetic determinants of flowering habit in strawberry at both the diploid and octoploid levels. A recessive gene conferring DN flowering habit has been identified, and its position determined with respect to molecular markers on the Fragaria vesca genetic linkage map. We are using the technique of bulked segregant analysis (BSA) in an effort to find random amplified polymorphic DNA (RAPD) markers linked to a putative dominant gene conferring the DN habit in the octoploid, cultivated strawberry, F. ánanassa.
Efforts to improve postharvest longevity of fresh-cut flowers has only recently turned toward selection and breeding. Conventional methods to extend keeping longevity of cut flowers depend on use of chemical treatment placed in holding solutions. Postharvest longevity studies were initiated with Antirrhinum majus L. (snapdragon) to determine: if natural genetic variation existed for cut-flower longevity, the inheritance of the trait, heritability, and associated physiology. Evaluation of commercial inbreds held in deionized water revealed a range in cut-flower longevity from a couple of days to 2.5 weeks. The shortest- and longestlived inbreds were used as parents in crosses to study the aforementioned areas of interest. Information will be presented on inheritance of cut flower longevity based on populations evaluated from matings for generation means analysis and inbred backcross method. Also presented will be information on stomata, transpiration, carbohydrate, fresh-weight change, and forcing temperature relative to postharvest longevity.
A teaching module was developed for computer-aided instruction of mutation theory. The Hypercard-driven, Macintosh compatible module illustrates the concepts of: 1) Changes in allele frequency with mutation pressure; 2) Number of alleles maintained in populations, and; 3) The Neutrality Hypothesis. The concepts are integrated in an application by using a game format.
Mutation is the ultimate source of genetic variation. Mutation pressure results in changes in allele frequency. Concept 1 illustrates the theoretical changes in allele frequency under pressure of reversible mutation. Mutation equilibrium is depicted as P=V/u+v; where v=mutation rates of allele A and u of allele a. The Infinite-Alleles Model of mutation is illustrated in Concept 2 and specifies characteristics of new mutations by F=1/4Nu+1, where F=fixation index and N=number in population. Concept 3 demonstrates the hypothesis that polymorphisms result from selectively neutral alleles maintained in a balance between mutation and random genetic drift.
A teaching module was developed for computer-aided instruction of mutation theory. The Hypercard-driven, Macintosh compatible module illustrates the concepts of: 1) Changes in allele frequency with mutation pressure; 2) Number of alleles maintained in populations, and; 3) The Neutrality Hypothesis. The concepts are integrated in an application by using a game format.
Mutation is the ultimate source of genetic variation. Mutation pressure results in changes in allele frequency. Concept 1 illustrates the theoretical changes in allele frequency under pressure of reversible mutation. Mutation equilibrium is depicted as P=V/u+v; where v=mutation rates of allele A and u of allele a. The Infinite-Alleles Model of mutation is illustrated in Concept 2 and specifies characteristics of new mutations by F=1/4Nu+1, where F=fixation index and N=number in population. Concept 3 demonstrates the hypothesis that polymorphisms result from selectively neutral alleles maintained in a balance between mutation and random genetic drift.