The inheritance of quantitative traits is not well understood. A study was conducted to determine the number and chromosomal locations of quantitative trait loci (QTL) controlling male anthesis date; plant and ear height; kernel weight; and kernel protein, oil, and starch concentration in maize (Zea mays L.). Two hundred S1 lines were derived from a single F1 plant from a cross of Illinois High Oil (IHO) by lllinois Low Oil (Early Maturity) [ILO(EM)]. Restriction fragment length polymorphism (RFLP) analysis was performed to determine RFLP genotypes of the 200 S1 families at 80 polymorphic loci spaced on average 24 centimorgans throughout the genome. The 200 S1 families were measured for phenotypic traits in replicated field trials during 1992 and 1993. Analysis of variance detected significant (P < 0.05) associations between several RFLP loci and each phenotypic trait. A total of 16 marker loci clustered in eight chromosomal regions were significantly associated with male anthesis date, 18 marker loci clustered in II regions were significantly associated with plant height, 14 marker loci clustered in nine regions were significantly associated with ear height, 27 marker loci clustered in II regions were associated with kernel weight, 16 marker loci clustered in eight regions were associated with protein concentration, 31 marker loci clustered in II regions were associated with oil concentration, and 28 marker loci clustered in 13 regions were associated with starch concentration. A number of QTL were detected in chromosomal regions where known gene loci of biological relevance are located.

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A study was conducted to determine the number and chromosomal location of quantitative trait loci (QTL) influencing the concentration of five fatty acids in 200 F2S1 lines derived from an Illinois High Oil (IHO) by Illinois Low Oil (Early Maturity) (ILO(EM)) cross. Restriction fragment length polymorphism (RFLP) analysis was performed on the 200 S1 lines and concentrations of palmitic (16:0), stearic (18:0), oleic (18:1), linoleic (18:2), and linolenic (18:3) acids were determined in self-pollinated kernels harvested from plants grown in replicated field trials during 1992 and 1993. A series of 74 cDNA and genomic clones were used and these revealed 80 polymorphic loci spaced, on average, 24 cM apart throughout the maize genome. Analysis of variance detected significant (p < 0.05) associations between several RFLP loci and the concentration of each fatty acid. A total of 15 RFLP loci clustered in 12 chromosomal regions were associated with the concentration of 16:0, 17 loci clustered in 10 regions were associated with the concentration of 18:0, 12 loci clustered in eight regions were associated with the concentration of 18:1 and 18:2, and 17 loci clustered in eight regions were associated with the concentration of 18:3. Multiple linear regression models consisting of four RFLP loci explained 24 and 62% of the total phenotypic and genotypic variation (R2) among the 200 F2S1 lines for 16:0, five loci explained 51 and 71% of the variation for 18:0, three loci explained 67 and 79% of the variation for 18:1, two loci explained 67 and 81% of the variation for 18:2, and seven loci explained 52 and 78% of the variation for 18:3 in these 200 F2S1 lines. The ratio of 18:1 to 18:2 was tightly interrelated as the same QTL were associated with the concentrations of 18:1 and 18:2. A quantitative trait locus that explained 63% of the phenotypic variation in the ratio of 18:1 to 18:2 is tightly linked to umc65 on chromosome 6 in the region of the linoleic acid1 locus.

A major limitation to the genetic improvement of wheat (Triticum aestivum L.) is the lack of information about quantitative trait loci (QTLs). The objective of this study was to determine the chromosomal locations of QTLs controlling grain yield and yield components, grain test weight, plant height, and anthesis date. Reciprocal sets of chromosome substitution lines in duplicate between two hard red winter wheat cultivars, Cheyenne (CNN) and Wichita (WI), were used to identify the chromosomes bearing QTLs. Field trials were conducted in Nebraska at Lincoln in 1987, at Lincoln, Mead, and Alliance in 1988, and at Lincoln, Mead, Alliance, and North Platte in 1989. Wichita had major QTLs on chromosomes 3A and 6A that increased grain yield in Cheyenne and major QTLs on chromosome 36 that decreased grain yield in Cheyenne, while Cheyenne had major QTLs on chromosomes 3A and 6A that decreased grain yield in Wichita. The increase in grain yield by WI 3A and WI 6A was due to a significant increase in seed weight. The decrease in grain yield by CNN 3A and CNN 6A was due to a significant decrease in culms per square meter. The decrease in grain yield by WI 3B was due to a significant decrease in winterhardiness, resulting in decreased seed weight and culms per square meter. We identified one Wichita and seven Cheyenne chromosomes with QTLs affecting seeds per culm, seven Wichita and five Cheyenne chromosomes with QTLs affecting seed weight, one Wichita and three Cheyenne chromosomes with QTLs affecting culms per square meter, and one or more chromosomes with QTLs affecting each of the other agronomic traits.

The application of advanced oxidation processes (AOPs) to the treatment of an effluent contaminated with hydrocarbon oils was investigated. The AOPs conducted were Fe 2+ /H 2 O 2 (Fenton's reagent), Fe 2+ /H 2 O 2 /UV (Photo-Fenton's reagent) and UV-photolysis. These technologies utilize the very strong oxidizing power of hydroxyl radicals to oxidize organic compounds to harmless end products such as CO 2 and H 2 O. A synthetic wastewater generated by emulsifying diesel oil and water was used. This wastewater might simulate, for example, a waste resulting from a hydrocarbon oil spill, onto which detergent was sprayed. The experiments utilising the Photo-Fenton treatment method with an artificial UV source, coupled with Fenton's reagent, suggest that the hydrocarbon oil is readily degradable, but that the emulsifying agent is much more resistant to degradation. The results showed that the COD (chemical oxygen demand) removal rate was affected by the Photo-Fenton parameters (Fe 2+ , H 2 O 2 concentrations and the initial pH) of the aqueous solution. In addition, the applicability of the treatment method to a 'real' wastewater contaminated with hydrocarbon oil is demonstrated. The 'real' wastewater was sourced at a nearby