TITLE:
Effects of Reciprocal Recurrent Selection on Grain Yield in Two Tropical-Temperate Maize Synthetic Populations Tuxpeño-Reid and Suwan-Lancaster
AUTHORS:
Zehui Chen, Yunfang Zhu, Angui Wang, Xiangyang Guo, Xun Wu, Pengfei Liu
KEYWORDS:
Reciprocal Recurrent Selection, Maize Germplasm, Population Improvement, Tropical
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.10 No.2,
February
27,
2019
ABSTRACT: 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.