Inheritance of Partial Male-Sterility in Guar.

A partial male-sterility system was found in a released guar, Cyamopsis tetragonoloba (L.) Taub. (2n = 2x = 14), breeding line, TX76-3285. Partially male-sterile plants produce some functional pollen, but with suitable genetic markers may be used to facilitate crossing in breeding programs. In addition, self fertilization allows partially male-sterile plants to be propagated sexually as homozygotes, once placed in breeding lines. The objective of the present study was to determine the inheritance of a partial male- sterility system in guar. Partial male-sterility appeared to be controlled by two genes, with one gene acting in a dominant epistatic manner and the second gene by incomplete dominance. The trait was expressed on every raceme beginning at about 4 to 6 weeks after planting in field-grown plants. The gene symbols, "pms1" and "Pms2" are proposed for the new trait. Segregation data indicated that alleles for pubescence segregated independently of alleles for partial male-sterility. Partial male-sterility in guar may be useful in the production of hybrid seed for breeding and genetic research. [ABSTRACT FROM AUTHOR]