Crop Biotech Update

Geneticists Analyze Vertical Root Pulling Resistance in Maize Using Two Genetic Populations

September 3, 2010

Aside from being an essential staple crop, maize is also used as biofuel, starch, and vegetable. The root system of maize is important in biomass and yield production due to its primary role in anchorage and acquisition of water and nutrients from the soil. Based on previous studies, vertical root pulling resistance (VRPR) has been found to be associated with root dry weight, root volume, and brace root number in maize. In China Agricultural University, Jianchao Liu and colleagues evaluated the VRPR, grain yield, stover yield, and nitrogen uptake of two genetic populations derived from the same parents. They conducted quantitative trait locus (QTL) analysis to explain the genetic basis of these complex traits. Twelve QTLs were detected in the population of advanced backcross BC4F3 lines, while there were 17 QTLs in the recombinant inbred lines (RILs). A certain QTL region was found to control VRPR, stover yield, and nitrogen uptake in both populations. These beneficial alleles are derived from the large-rooted parent Ye478. There was positive correlation between VRPR, stover yield and nitrogen uptake. Backcross lines containing the VRPR QTLs could be used as germplasm for producing map-based cloning of genes coding for root growth.

The abstract of this study is available at