TEOSINTE CYTOPLASMIC GENOMES .1. PERFORMANCE OF MAIZE INBREDS WITH TEOSINTE CYTOPLASMS

Cytoplasmic variation in maize (Zea mays L,) is known to influence qua litative phenotypes such as male sterility and teosinte-cytoplasm asso ciated miniature. Cytoplasmic influences on quantitative characters su ch as grain yield have been difficult to document. The objective of th is research was to study effects of diverse teosinte cytoplasmic genom es on quantitative agronomic characters in two maize inbreds. Ten dive rse cytoplasms derived from three subspecies of Z, mays and one Z. per ennis cytoplasm were substituted for the cytoplasms of inbreds A619 an d W23 by at least six generations of backcrossing. Inbreds with teosin te cytoplasms were compared with A619 and W23 in a replicated field tr ial in three environments, Five of the 11 cytoplasms had quantitative influences, Three of these five cytoplasms decreased yield, with one o f the cytoplasms reducing yield of the A619 nuclear genotype by 1.07 M g ha(-1) or 20%. Many effects were specific to either the A619 or W23 nuclear background indicating that teosinte cytoplasmic genomes intera cted with maize nuclear genomes, Cytoplasmic effects tended to be smal l and unfavorable in the context of a maize breeding program.