Uncovering hidden genetic variation in photosynthesis of field‐grown maize under ozone pollution

Ozone is the most damaging air pollutant to crops, currently reducing Midwest US maize production by up to 10%, yet there has been very little effort to adapt germ‐ plasm for ozone tolerance. Ozone enters plants through stomata, reacts to form reactive oxygen species in the apoplast and ultimately decreases photosynthetic C gain. In this study, 10 diverse inbred parents were crossed in a half‐diallel design to create 45 F1 hybrids, which were tested for ozone response in the field using free air concentration enrichment (FACE). Ozone stress increased the heritability of pho‐ tosynthetic traits and altered genetic correlations among traits. Hybrids from par‐ ents Hp301 and NC338 showed greater sensitivity to ozone stress, and disrupted relationships among photosynthetic traits. The physiological responses underlying sensitivity to ozone differed in hybrids from the two parents, suggesting multiple mechanisms of response to oxidative stress. FACE technology was essential to this evaluation because genetic variation in photosynthesis under elevated ozone was not predictable based on performance at ambient ozone. These findings suggest that selection under elevated ozone is needed to identify deleterious alleles in the world's largest commodity crop

Is it possible that the pathogenesis of osteoarthritis could start with subchondral trabecular bone loss like osteoporosis?

This study aims to investigate the role of subchondral trabecular bone thickness in the mechanism of knee osteoarthritis and the correlation of osteoarthritis and osteoporosis pathogenesis