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LEAFY COTYLEDON expression in the endosperm enables embryo maturation in Arabidopsis

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The endosperm provides nutrients and growth regulators to the embryo during seed development.  LEAFY COTYLEDON (LEC1) has long been known to be essential for embryo maturation. LEC1 is expressed in both the embryo and the endosperm; however, the functional relevance of the endosperm-expressed  LEC1  for seed development is unclear. Here, we provide genetic and transgenic evidence demonstrating that endosperm-expressed  LEC1  is necessary and sufficient for embryo maturation. We show that endosperm-synthesized LEC1 is capable of orchestrating full seed maturation in the absence of embryo-expressed  LEC1 . Inversely, without  LEC1  expression in the endosperm, embryo development arrests even in the presence of functional  LEC1  alleles in the embryo. We further reveal that  LEC1  expression in the endosperm begins at the zygote stage and the LEC1 protein is then trafficked to the embryo to activate processes of seed maturation. Our findings thus establish a key role for endosperm in reg
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Natural variations at the Stay-Green gene promoter control lifespan and yield in rice cultivars

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Increased grain yield will be critical to meet the growing demand for food, and could be achieved by delaying crop senescence. Here, via quantitative trait locus (QTL) mapping, we uncover the genetic basis underlying distinct life cycles and senescence patterns of two rice subspecies,  indica  and  japonica . Promoter variations in the  Stay-Green  ( OsSGR ) gene encoding the chlorophyll-degrading Mg ++ -dechelatase were found to trigger higher and earlier induction of  OsSGR  in  indica , which accelerated senescence of  indica  rice cultivars. The  indica -type promoter is present in a progenitor subspecies  O. nivara  and thus was acquired early during the evolution of rapid cycling trait in rice subspecies.  Japonica OsSGR  alleles introgressed into  indica -type cultivars in Korean rice fields lead to delayed senescence, with increased grain yield and enhanced photosynthetic competence. Taken together, these data establish that naturally occurring  OsSGR  promoter and related life
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Natural variations at the Stay-Green gene promoter control lifespan and yield in rice cultivars

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  Increased grain yield will be critical to meet the growing demand for food, and could be achieved by delaying crop senescence. Here, via quantitative trait locus (QTL) mapping, we uncover the genetic basis underlying distinct life cycles and senescence patterns of two rice subspecies,  indica  and  japonica . Promoter variations in the  Stay-Green  ( OsSGR ) gene encoding the chlorophyll-degrading Mg ++ -dechelatase were found to trigger higher and earlier induction of  OsSGR  in  indica , which accelerated senescence of  indica  rice cultivars. The  indica -type promoter is present in a progenitor subspecies  O. nivara  and thus was acquired early during the evolution of rapid cycling trait in rice subspecies.  Japonica OsSGR  alleles introgressed into  indica -type cultivars in Korean rice fields lead to delayed senescence, with increased grain yield and enhanced photosynthetic competence. Taken together, these data establish that naturally occurring  OsSGR  promoter and related li
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Ecological and evolutionary approaches to improving crop variety mixtures

Variety mixtures can provide a range of benefits for both the crop and the environment. Their utility for the suppression of pathogens, especially in small grain crops, is well established and has seen some remarkable successes. However, despite decades of academic interest in the topic, commercial efforts to develop, release and promote variety mixtures remain peripheral to normal breeding activities. Here we argue that this is because simple but general design principles that allow for the optimization of multiple mixture benefits are currently lacking. We therefore review the practical and conceptual challenges inherent in the development of variety mixtures, and discuss common approaches to overcome these. We further consider three domains in which they might be particularly beneficial: pathogen resistance, yield stability and yield enhancement. We demonstrate that combining evolutionary and ecological concepts with data typically available from breeding and variety testing program
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Animals are replaced with grass in cultured meat.

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 An affordable lab system uses grass blades to turn cells into cultured meat, by creating a scaffold that animal stem cells can attach to and grow on.
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