Author(s)

Zehui Chen, Yunfang Zhu, Angui Wang, Xiangyang Guo, Xun Wu^*, Pengfei Liu

Upland Crops Institute, Guizhou Academy of Agricultural Sciences, Guiyang, China.

Reid, Lancaster, Tuxpeno and Suwan are the most common maize (Zea mays L.) germplasms. Reid × Lancaster and Suwan × Tuxpeno are very important heterotic patterns in temperate areas and tropical areas, respectively. Broadening the genetic basis of maize has usually been conducted in inter-populations formed by crossing temperate and tropical germplasms. Reciprocal recurrent selection (RRS) is a breeding procedure to improve the inter-populational cross of two base populations. The objective of this study was to evaluate the direct and indirect effects of reciprocal recurrent selection on grain yield in the TR (Tuxpeno-Reid) and SL (Suwan-Lancaster) maize populations. The populations and the inter-populational crosses of each selection cycle, as well as two commercial hybrids, were evaluated in four environments. The effect of mean grain yield on TR × SL inter-population crosses was 4.63% (or 0.365 Mg·ha^-1) cycle^-1. The grain yield of SL increased by 2.78% (or 0.20 Mg·ha^-1) cycle^-1, but the grain yield of TR essentially did not change. Most changes in other agronomic traits occurred in the desired direction. After 3 selection cycles, the ear tip-barrenness length decreased in TR × SL, TR and SL by 39.70%, 37.50% and 24.57%, respectively, which indicates that the increase in grain yield may be largely due to a decreasing ear tip-barrenness length. The mid-parent heterosis of grain yield of the inter-populational cross increased from 15.49% to 25.96% from C0 to C3. The mean grain yields of TRC3 × SLC3 were 100.01% and 103.88% of the mean grain yields of the commercial single-crosses GD8 and QD16, respectively. The results suggest that Tuxpeno-Reid × Suwan-Lancaster may be possible new heterotic patterns in the southern region of China.

Reciprocal Recurrent Selection, Maize Germplasm, Population Improvement, Tropical

Chen, Z. , Zhu, Y. , Wang, A. , Guo, X. , Wu, X. and Liu, P. (2019) Effects of Reciprocal Recurrent Selection on Grain Yield in Two Tropical-Temperate Maize Synthetic Populations Tuxpeño-Reid and Suwan-Lancaster. American Journal of Plant Sciences, 10, 298-308. doi: 10.4236/ajps.2019.102023.