Front cover image:

Global warming and food security are preeminent worldwide concerns. Various crop plants are exposed to heat stress during critical reproductive stages, having a devastating impact on yield. The cover illustration shows that redox-engineered maize plants, through constitutive ectopic expression of a single gene coding for the monothiol glutaredoxin S17 (AtGRXS17), display robust thermotolerance without any adverse growth effects during reproductive and grain-filling stages, resulting in large yield increases in both greenhouse and fi eld conditions. Cover illustration refers to the article in this issue (Park et al., 1819–1832).

Cultivated lettuce (Lactuca sativa), domesticated from prickly lettuce (L. serriola), is one of the most important green leafy vegetables worldwide. Lettuce is also a model species for hydroponics, and an ideal plant to be engineered to produce oral vaccines or valuable pharmaceuticals. Leaf shape is an important trait for plant species, and leaf shape per se is an agronomic trait for leafy vegetables such as lettuce. Lobed leaves have been studied in several species. However, the mechanism underlying the variation between pinnately and palmately lobed leaves remain unclear. For the first time, we dissected the genetic mechanisms underlying palmately lobed leaves in plants, providing novel insights on leaf development. The palmately lobed leaves contribute to the sensory quality of lettuce, and our results will facilitate the breeding of lettuce cultivars with ideal leaf shapes.

GM Camelina in the field in Hertfordshire, England.