The Journal of Heredity 1986:77(6):475-476
© 1986 The American Genetic Association 77:475-476
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Early Identification of chlorophyil deficiency heterozygotes in large-seeded legumes
Drs. Davis and Kiang are affiliated with the Plant Science Department, Nesmith Hall, University of New Hampshire, Durham NH 03824; Dr. Ehlers is with I.C.I.P.E., Mbita Point Field Station, P.O. Box 30, Mbita, Kenya. Scientific Contribution no. 1438 from the New Hampshire Agricultural Experiment Station.
Abstract
Mutations resulting in chlorophyll-deficient seedlings were shown to be expressed in the developing cotyledons of immature seed of chickpeas, cowpeas, and soybeans. Normally pigmented plants in generations segregating for chlorophyll deficiency traits were determined to be homozygous (+/+) or heterozygous (+/–) by examining developing seed during the pod-fill stage. Normal (+/+) homozygotes produced seed with only green cotyledons, while heterozygotes (+/–) produced two types of seed—with either green or white cotyledons. Accurate genotypic classification, as confirmed by conventional progeny testing, was possible with four chickpea mutants, a cowpea mutant, and the F2 generation of a cross between chlorophyll-deficient soybean (Glycine max (L.) Merr.) line T233 and wild soybean (G. soja Sleb. & Zucc.) P.I. 486.200. However, developing cotyledons were green regardless of plant genotype in the F2 generation of the cross, T233 X soybean cv. Vansoy. Early progeny testing (EPT), based on immature embryo classification, may be used to advantage in genetic studies of appropriate chlorophyll mutants in large-seeded legumes and perhaps other dicots.