domestication: a new way for crop design and breeding.

The impending global climate change presents significant challenges to agricultural production. It is imperative to find approaches to ensure sustained growth in food production while reducing agricultural input, in order to meet the needs of worldwide people for nutritious food supply. One of the effective strategies to address this challenge is still the development of new crop varieties with high yield, stable yield, environmental friendliness and rich nutrition.

A genome-wide survey of maize lipid-related genes: candidate genes mining, digital gene expression profiling and co-location with QTL for maize kernel oil.

Lipids play an important role in plants due to their abundance and their extensive participation in many metabolic processes. Genes involved in lipid metabolism have been extensively studied in Arabidopsis and other plant species. In this study, a total of 1003 maize lipid-related genes were cloned and annotated, including 42 genes with experimental validation, 732 genes with full-length cDNA and protein sequences in public databases and 229 newly cloned genes.

Improving QTL mapping resolution based on genotypic sampling--a case using a RIL population.

The QTL mapping results were compared with the genotypically selected and random samples of the same size on the base of a RIL population. The results demonstrated that there were no obvious differences in the trait distribution and marker segregation distortion between the genotypically selected and random samples with the same population size. However, a significant increase in QTL detection power, sensitivity, specificity, and QTL resolution in the genotypically selected samples were observed.

[QTL mapping of five agronomic traits in maize].

Agronomic traits have significant influence on stability and adaptability in maize production. In this investigation, using a population with 266 F2:3 families from Yuyu22 (Zong3 x 87-1), two-location field tests were conducted in Wuhan and Xiangfan in 2001, with a randomized complete block design, to characterize five agronomic traits: ear height, tassel branch number, stalk diameter, days to pollen, and days to silk. Correlation analysis of field performance indicated that ear height, tassel branch number and stalk diameter were significantly positive correlative with single-plant yield, days to pollen and days to silk were highly positive correlative with each other, and tassel branch number was significantly positive correlative with stalk diameter too.

[Comparative analyses of QTL for important agronomic traits between maize and rice].

The objective of this study was to assess syntenic relationships of quantitative trait loci (QTL) for important agronomic traits between maize and rice based on the comparative genomic map of maize and rice using two F(2:3) populations. Through the comparisons, it was observed that there were extensive conserved relationships of maize QTL affected plant height, row number, and kernels per row with rice QTL affected plant height, tillers per plant, and grains per panicle respectively. Sixteen of 45 QTL affecting five different maize traits were conserved compared with 12 of 38 QTL affecting five different rice traits, which provided some useful information for locating, isolating and cloning maize QTL by using the rice genomic data.

[Genetic analysis of segregation distortion of molecular markers in maize F2 population].

A genetic linkage map of maize was constructed using 150 SSR and 24 RFLP markers, with F2 population from an elite hybrid (Zong3 x 87-1). Among 174 markers, covering whole maize 10 chromosomes, 49 markers (28.1%) showed the genetic distortion (P < 0.