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Lettuce, in its cultivated form (Lactuca sativa L.), is a crop of economic importance with several characteristics which make it well suited for biochemical and genetic studies. Biochemical traits such as proteins and enzymes have been studied extensively in many plant species and constitute an important experimental approach to physiological, evolutionary, taxonomic and breeding studies. Seed proteins were extracted from an array of lettuce cultivars. Polyacrylamide gel electrophoresis was employed in a comparative analysis of the soluble protein and isozyme characteristics of seed from each cultivar. Some fall-desert, winter-desert, and coastal cultivars were distinguishable based upon variation in soluble proteins or esterase isozymes. Multiple forms of the carboxylic ester hydrolases or esterases have been shown to occur in a wide variety of plants; their role in the plant cell is still however poorly understood. The inheritance of the esterase isozymes was analyzed by a microelectrophoresis technique which enabled the analysis of individual seeds in the progeny from a cross involving two winter-desert cultivars of contrasting banding phenotypes. Two distinct banding patterns were observed in single seeds of these cultivars; their F₁ hybrid showed a summation of parental patterns, the F₂ segregated in a 1:2:1 phenotypic ratio for these esterase patterns, and backcross segregation ratios were 1:1. Banding pattern differences could be accounted for by the segregation of a single gene with codominant action. Quantitative as well as qualitative differences in esterase activity were observed between the parental lines from two different years of production. Some esterase isozymes were developmentally regulated. Molecular weight determination experiments verified the presence of two gene products of 56 and 62.5 Kd.

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Min was one of the earliest known Egyptian deities and his origins remain obscure but, because of his association with fertility and the kingship, he retained his importance from the Predynastic Period into the Roman era. Although his depiction as an ithyphallic, mummified male with a flail balanced above his raised right arm remained unaltered throughout, the overall iconography of Min did exhibit changes, notably with the introduction in the Sixth Dynasty of what is accepted as a lettuce plant resembling the modern Cos or Romaine cultivar of Lactuca sativa L. It is the association of Min with the lettuce plant that is the subject of this thesis. It is the received opinion in the literature that the plant was offered to Min, a fertility god, as an aphrodisiac. Apart from two seminal works that are over fifty years old, little research has been conducted into the association of Min with the lettuce. Much early research is in need of re-examination because of changes in social attitudes and research techniques and this the thesis seeks to redress. The aims of the research are to review the evidence for the lettuce plant in ancient Egypt and to re-examine the previously noted association of the god Min with a plant identified as lettuce. The study is primarily library and museum based and examines the history and nature of lettuce in ancient Egypt. The nature of 'aphrodisiac' is examined and the use of such substances in ancient Egypt is compared with modern usage. Min as a god of fertility is re-analysed and, finally, texts and Ptolemaic temple inscriptions are examined for evidence as to why and by whom lettuce was offered. The research results are applied to a study of Min as a god of fertility. The evidence indicates that lettuce was offered by the king to Min to ensure the fertility and regeneration of agriculture and of the king which would secure the continuation of his line and humanity. There is no evidence to suggest lettuce was offered as an aphrodisiac to increase the sexual desire of the god.

Thesis (M.Phil.)--Chinese University of Hong Kong. / Bibliography: leaves 109-121.