Applications & Publications

Testing Pollen Sorted by Flow Cytometry as the Basis for High-Resolution Lacustrine Chronologies

A new seed-based assay for meiotic recombination in Arabidopsis thaliana

Meiotic recombination is a fundamental biological process that plays a central role in the evolution and breeding of plants. We have developed a new seed-based assay for meiotic recombination in Arabidopsis. The assay is based on the transformation of green and red fluorescent markers expressed under a seed-specific promoter. A total of 74 T-DNA markers were isolated, sequenced and mapped both physically and genetically. Lines containing red and green markers that map 1–20 cM apart were crossed to produce tester lines with the two markers linked in cis yielding seeds that fluoresced both in red and green. We show that these lines can be used for efficient scoring of recombinant types (red only or green only fluorescing seeds) in a seed population derived from a test cross (backcross) or self-pollination. Two tester lines that were characterized during several generations of backcross and self-pollination, one in the background of ecotype Landsberg and one in the ecotype Columbia, are described. We discuss the number of plants and seeds to be scored in order to obtain reliable and reproducible crossing over rate values. This assay offers a relatively high-throughput method, with the benefit of seed markers (similar to the maize classical genetic markers) combined with the advantages of Arabidopsis. It advances the prospect to better understand the factors that affect the rate of meiotic crossover in plants and to stimulate this process for more efficient breeding and mapping.

(1) Department of Plant Sciences, Weizmann Institute of Science, Rehovot 76100, Israel, and (2) Department of Genetics, Institute for Molecular Cell Biology, Vrije Universiteit, de Boelelaan 1087,1081 HV, Amsterdam, The Netherlands

DOI:10.1111/j.1365-313X.2005.02466.x

Cytometric Sorting of Pinaceae Pollen and its Implications for Radiocarbon Dating and Stable Isotope Analyses.

(1) Department of Geography, UC Berkeley, Berkeley CA, (2) Department of Earth and Planetary Science, UC Berkeley, Berkeley CA, (3) Union Biometrica, Holliston, MA.