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Chaos Of Torin 1

g. favouring high variance and rapid shattering to escape from management practices). To examine the origins of and interactions among cultivated rice and conspecific wild and weedy relatives, these two studies ABT-737 sequentially address the single, independent introduction of versus continued derived source of U.S. weedy rice populations and then examine whether a key trait involved in weediness, seed shattering, evolved independently in U.S. weedy rice. Together, these results present a fascinating story regarding how traits characterizing this conspecific weed have been shaped by genetic interactions with globally diverse cultivated rice lineages and mediated by selection at genes playing pivotal roles in traits that are essential for survival from eradication practices. Gross et?al. (2010) addresses whether U.S. weedy rice is derived from either undomesticated Oryza populations related to aus and/or indica lineages that also gave rise to Asian rice domesticates or from already existing wild and/or weedy rice populations initially descended from Asian domesticates that later spread to North America. To test these alternative hypotheses, this study takes advantage of a Hesperadin sharply contrasting phenotype distinguishing cultivated rice from weedy red rice: pericarp pigment (the outer covering of the seed). In cultivated rice, it is desirable to have uniform size and colour of grains. Although rice with purple or red grains is cultivated in other world regions, practically all U.S. cultivated rice has purely white pericarps whereas U.S. weedy rice has red pericarp. Indeed, the zero tolerance policy for red rice contamination in learn more the U.S. and in other countries requires cultivated rice varieties to harbor no alleles leading to pigmented pericarps. The authors further take advantage of strong selection against alleles resulting in pigmented pericarps in cultivars by examining DNA sequence variation in the 6.4?kb Rc locus plus 1.6?kb upstream and 0.8?kb downstream, respectively, of the start and stop codons of this proanthocyanidin-encoding gene. Additionally, this study also sequenced ?500?bp fragments at points spanning 2.1?Mb upstream and 2.0?Mb downstream from the Rc gene. The size of the sequenced region is within the <1?Mb size range that a previous report showed as the range of the selective sweep in this gene (Sweeney et?al. 2007). Most modern domesticated rice varieties lack pericarp proanthocyanidin pigments. Thus molecular evolutionary analyses comparing the loss-of-function alleles in cultivated rice can be used to ascertain the genetic distance and patterns of relatedness among weedy red rice conspecifics and to test whether particular U.S. weedy red rice populations originate directly from Asian cultivated lineages, U.S. cultivated lineages, or from other Asian weedy/wild populations.</div>
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