Sand rice,a promising future crop for desert and marginal lands in northern China

The pioneer Amaranthaceae species sand rice(Agriophyllum squarrosum)is an annual psammophyte that is widely distributed in the deserts and sand fields of northern China.The well-balanced nutritional values,long consumption history,and extreme stress tolerance of sand rice have fascinated scientists,prompting its development as a climate-resilient crop.Sand rice has been successfully introduced and cultivated on sandy and loess lands over the past decade,while large-scale artificial planting has been carried out in the Ulan Buh and Tengger deserts.However,the yield is far below the maximum potential,as estimated by the highest yield per plant ever found in the Tengger desert during our survey of wild populations.The current domestication of sand rice relies mainly on natural selection and mutagenesis breeding.A few elite lines with modified agronomic traits,such as compact architecture,high productivity,reduced trichomes,and short plant stature,have been developed from natural populations and a chemical mutagenesis library.Breeding new cultivars and broader cultivation of sand rice in deserts and marginal lands will stimulate economic growth and diversify the food supply,especially for the area west of the Hu Huanyong Line,thus contributing to environmental sustainability in northern China.

Harnessing Knowledge from Maize and Rice Domestication for New Crop Breeding

Crop domestication has fundamentally altered the course of human history,causing a shift from huntergatherer to agricultural societies and stimulating the rise of modern civilization.A greater understanding of crop domestication would provide a theoretical basis for how we could improve current crops and develop new crops to deal with environmental challenges in a sustainable manner.Here,we provide a comprehensive summary of the similarities and differences in the domestication processes of maize and rice,two major staple food crops that feed the world.We propose that maize and rice might have evolved distinct genetic solutions toward domestication.Maize and rice domestication appears to be associated with distinct regulatory and evolutionary mechanisms.Rice domestication tended to select de novo,loss-of-function,coding variation,while maize domestication more frequently favored standing,gain-offunction,regulatory variation.At the gene network level,distinct genetic paths were used to acquire convergent phenotypes in maize and rice domestication,during which different central genes were utilized,orthologous genes played different evolutionary roles,and unique genes or regulatory modules were acquired for establishing new traits.Finally,we discuss how the knowledge gained from past domestication processes,together with emerging technologies,could be exploited to improve modern crop breeding and domesticate new crops to meet increasing human demands.