The Use of Full-Sib Recurrent Selection in the Improvement of an Open Pollinated Corn Population for Use in Sustainable Agricultural Systems

Synthetic varieties of Corn (Zea mays L.) are better buffered against environmental stresses in sustainable agricultural systems than cu.itivars with a narrow genetic base. A full-sib (FS) recurrent selection (RS) program was started at the University of Florida using a tropical open pollinated com population The goal was to develop a synthetic with a broad genetic base suitable to be grown during the fall in north-central Florida under conservation practices. Full-sib crosses were made in the spring of 1987. Then, in August a progeny test was planted in a randomized complete block design with si..x replications. Collected data included; ear, husk, and grain weight, insect damage (ID), whole plant yield (WY), seed and leaf N percent, and plant height. Analyses included ANOV A, correlations (r), heritabilities, and frequency distribution. There were differences betweenFS families for most of the traits. Ear weiglit (EW) was highly positively r (+ r) with yield and plant height traits. Ear weight was negatively r (-r) with ID and+ r with leaf N percent of FS families. Tip ID was -r with husk weight. Heritability varied for all traits. The mean EW of the FS were higher than the parents and the Pioneer hybrid X-304C. Selection for EW improved WY, earworm (Heliotliis zea L.) tolerance and N uptake.