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Summary Barley ( Hordeum vulgare L.) is a major cereal grain widely used for livestock feed, brewing malts and human food. Grain yield is the most important breeding target for genetic improvement and largely depends on optimal timing of flowering. Little is known about the allelic diversity of genes that underlie flowering time in domesticated barley, the genetic changes that have occurred during breeding, and their impact on yield and adaptation. Here, we report a comprehensive genomic assessment of a worldwide collection of 895 barley accessions based on the targeted resequencing of phenology genes. A versatile target‐capture method was used to detect genome‐wide polymorphisms in a panel of 174 flowering time‐related genes, chosen based on prior knowledge from barley, rice and Arabidopsis thaliana . Association studies identified novel polymorphisms that accounted for observed phenotypic variation in phenology and grain yield, and explained improvements in adaptation as a result of historical breeding of Australian barley cultivars. We found that 50% of genetic variants associated with grain yield, and 67% of the plant height variation was also associated with phenology. The precise identification of favourable alleles provides a genomic basis to improve barley yield traits and to enhance adaptation for specific production areas.

In a prospective, longitudinal, population‐based cohort study of familial and environmental influences on the development of wheezing respiratory illness in early childhood, we identified infant length, weight, gender, and exposure to maternal cigarette smoking as significant determinants of lung function during the first year of life. A cohort of 237 infants (106 females: 131 males) was evaluated, and 496 lung function measurements were made between the ages of 1–12 months. Respiratory function was assessed using the rapid thoracic compression technique to obtain maximum expiratory flow at functional residual capacity (V′maxFRC). Parental history of asthma and smoking habits during pregnancy were obtained by questionnaire. Data were analyzed using a longitudinal random effects model. Infants with a parental history of asthma and/or in utero passive smoke exposure were compared to a reference group of infants who had no parental history of asthma and in whom neither parent smoked pre‐ or postnatally. Boys were found to have a consistently lower V′maxFRC (−21.05 mL.s−1) throughout the first year of life in comparison to girls (P < 0.05). Maternal smoking during pregnancy was associated with a lower V′maxFRC in both genders in comparison to unexposed infants (P < 0.05). V′maxFRC was unaffected by parental history of asthma. Gender‐specific normative equations for V′maxFRC throughout the first year of life were derived for the infant cohort as a whole and also for subgroups of infants, based on parental asthma and smoking history. We conclude that lung function during the first year of life differs between genders and is adversely affected by in utero passive tobacco smoke exposure. Gender‐specific predictive equations for V′maxFRC should be used during infancy. Pediatr Pulmonol. 2000; 29:331–340. © 2000 Wiley‐Liss, Inc.