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In agriculture, shattering is the dispersal of a crop's seeds upon their becoming ripe. From an agricultural perspective this is generally an undesirable process, and in the history of crop domestication several important advances have involved a mutation in a crop plant that reduced shattering — instead of the seeds being dispersed as soon as they were ripe, the mutant plants retained the seeds for longer, which made harvesting much more effective. A particularly important mutation that was selected very early in the history of agriculture removed the "brittle rachis" problem from wheat. A ripe head ("ear") of wild-type wheat is easily shattered into dispersal units when touched, or blown by the wind, because during ripening a series of abscission layers forms that divides the rachis into short segments, each attached to a single spikelet (which contains 2–3 grains along with chaff). A different class of shattering mechanisms involves dehiscence of the mature fruit, which releases the seeds. Current research priorities to understand the genetics of shattering include the following crops: * Barley * Buckwheat〔(Ivan N. FESENKO 2006. Non-shattering accessions of ''Fagopyrum tataricum'' Gaertn. carry recessive alleles at two loci affecting development of functional abscission layer. ''Fagopyrum'' 23: 7-10 )〕 * Grain Amaranth〔(Brenner, D.M. 2002. Non-shattering grain amaranth populations. p. 104–106. In: J. Janick and A. Whipkey (eds.), Trends in new crops and new uses. ASHS Press, Alexandria, VA. )〕 * Oilseed rape (''Brassica napus'') Sesame and canola are harvested before the seed is fully mature, so that the pods do not split and drop the seeds. ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Shattering (agriculture)」の詳細全文を読む スポンサード リンク
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