A selection procedure for ear drying-rates in maize

Abstract

Rewiwl 10 April I984 INDEX WORDS Zeamays, maize, ear moisture, dry-down rate. SUMMARY A selection procedure to change the drying rates of maize (Z~LI mays L.) ears was developed and tested. Results indicated that drying rates were affected by hybrid genotype, ear maturity at harvest, number of kernels per row, ear diameter.and moisture content at harvest. Mass selection was initiated in an early synthetic, NDSG, in an attempt to produce both fast and slow drying strains. After two cycles resultant substrains were evaluated in the laboratory for direct and in the field for correlated selection responses. Laboratory results indicated that selection effectively changed moisture loss rates in NDSG, and confirmed earlier observations that an ear's moisture content at harvest affects its drying rate.Data from field experiments grown at five locations in 1980 revealed that each of two selection cycles for slow laboratory drying rate significantly reduced ear moisture content at harvest, in the field. This lower harvest moisture content appeared to result from a lower moisture content at physiological maturity rather than a faster drying rate. Other correlated selection responses included lowered yield. plant height. and ear weight due to selection for fast laboratory drying, and lowered plant height and ear weight from selection for slow drying.Data indicated that this selection procedure can be used to change moisture loss rate and ear moisture content at harvest. Results also contributed to understanding of factors involved in ear drying rates which may lead to more effective selection procedures.

Characterization of correlation between grain moisture and ear rot resistance in maize by QTL meta-analysis

“…If grain moisture increases, shelling efficiency and grain quality will be reduced and drying costs and shrink age penalties increase (Johnson et al 1963, Sweeney et al 1994. Ear moisture differences at physiological maturity were deemed important (Cross 1985). Selection inbred lines based on low ear moisture at 45 day post-pollination could effectively reduce ear moisture at harvest (Cross et al 1987;Cross and Kabir 1989).…”

QTL Detection for Grain Water Relations and Genetic Correlations with Grain Matter Accumulation at Four Stages after Pollination in Maize

“…A negative correlation between late-season drying rate and grain moisture at harvest was reported by Kang and Zuber [56]. Selection of inbred lines based on low GWC at early stages has been proved effective in reducing GWC at harvest [37][38][39].…”

“…Besides, low GWC and high Grain Dehydration Rate (GDR) at harvest were very important for maize production in temperate regions (midto short-season areas, such as Huanghuihai maize belt in China), which could facilitate machinery harvest, shelling efficiency, grain quality and reduce additional drying cost and shrinkage penalties [28,[33][34][35][36]. Previous research has shown that selection of inbred lines based on low ear-moisture content at a given date after pollination was an effective way to result in low grain moisture content at harvest for inbred lines and associated hybrids [37][38][39]. However, QTL mapping for grain water relations had been reported mostly for Grain Water Content at harvest [21,36,[40][41][42].…”

Genetic analysis of two new quantitative trait loci for ear weight in maize inbred line Huangzao4

“…Ear weight (EW) is a very important trait in maize (Zea mays L.) breeding programs related to yield (Cross, 1985), but at present, a maize germplasm with high EW is quite lacking. To resolve this problem, an effective solution is to utilize elite genes associated with EW to improve the trait.…”