Antibody to the 11S seed storage protein of alfalfa and to the 14.5S seed storage protein of lettuce were prepared during Phase I. In Phase II, the PIs propose to use these antibodies to determine the developmental stage of somatic embryos of both crops. In alfalfa, 11S storage protein will be measured during zygotic seed maturation and during germination. This will determine a timetable against which the development of somatic embryos can be compared. Conditions of alfalfa somatic embryo culture are presented which result in very high rates of embryo germination. Somatic embryos from these treatments will be tested and a correlation determined between embryo germination and 11S seed protein accumulation. Conditions which control precocious germination of somatic embryos will be tested for the loss of 11S storage protein in alfalfa. In lettuce, a similar developmental timetable for zygotic embryos will be established. Lettuce cell cultures will be initiated in which conditions for embryo propagation will be established. Conditions for embryo maturation will be studied with respect to 14.5S protein. The overall objective of the proposal is to improve commercial plant propagation using somatic embryogenesis. The specific objective is to determine whether storage protein levels in somatic embryos correlate with embryo development and vigor. On this assumption, the PIs anticipate improving somatic embryo development by increasing internal protein storage reserves.
