The USDA announces the release of cultivar ‘AlkarXL’ (Reg. no. CV‐286, PI 691611) tall wheatgrass [Thinopyrum ponticum (Podp.) Barkworth & D. R. Dewey] for use on semiarid rangelands and irrigated pastures that receive a minimum of 350 mm of average annual precipitation on alkali soils. AlkarXL is a 10‐clone synthetic that originated from 56 plant introductions from the National Plant Germplasm System plus the cultivar Alkar. AlkarXL has undergone phenotypic recurrent selection for visual plant vigor (first cycle), seed yield (first cycle), dry‐matter yield (DMY) (second cycle), and crude protein (second cycle). The 10 genotypes traced to PI 255146 (two genotypes; 30%, Turkey), PI 308592 (10%, Italy), PI 442631 (10%, Turkey), PI 109542 (10%, Turkey), PI 255443 (10%, Turkey), PI 383545 (10%, Turkey), PI 401006 (Turkey), PI 401009 (10%, Turkey), and W6 21870 (10%, Ukraine). Morphologically, AlkarXL has significantly wider lemmas and glumes and shorter glumes than cultivars Alkar, Greenstar, Jose, Largo, and Szarvasi‐1. AlkarXL had narrower flag leaves than Largo. AlkarXL had more seedlings (P < .05) emerge than Alkar at Lages Junction, NV. AlkarXL had greater (P < .05) plant persistence (plant frequency) 3 (2017), 4 (2018), and 5 (2019) yr after seeding at Lages Junction than did Alkar. Dry‐matter yield was less descriptive due to large variations in DMY among replications. AlkarXL had significantly (P < .10) more total DMY than Greenstar and Largo at Millville, UT, and similar DMY as Greenstar, Jose, and Savarsi‐1 at Panguitch, UT.

中文翻译：

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'AlkarXL'，一种新的高小麦草栽培品种，用于盐渍半干旱地区

美国农业部宣布品种的释放“AlkarXL”（注册号CV-286，PI 691611）高冰草[偃ponticum（Podp。）Barkworth＆DR Dewey]用于半干旱牧场和灌溉草场，在碱土上平均年降水量至少为350毫米。AlkarXL是一种10克隆合成物，源自国家植物种质系统和Alkar品种的56种植物引种。AlkarXL已针对视觉植物活力（第一周期），种子产量（第一周期），干物质产量（DMY）（第二周期）和粗蛋白（第二周期）进行了表型轮回选择。这10个基因型可追溯到PI 255146（两个基因型； 30％，土耳其），PI 308592（10％，意大利），PI 442631（10％，土耳其），PI 109542（10％，土耳其），PI 255443（10％，土耳其），PI 383545（10％，土耳其），PI 401006（土耳其），PI 401009（10％，土耳其）和W6 21870（10％，乌克兰）。从形态上讲 与品种Alkar，Greenstar，Jose，Largo和Szarvasi-1相比，AlkarXL的引物和颖片明显更宽，颖片较短。AlkarXL的旗叶比Largo窄。AlkarXL的幼苗更多（P  <.05）比内华达州拉格斯章克申的阿尔卡（Alkar）出现。 在Lages Junction播种后，AlkarXL在Lages Junction播种的植物持久性（植物频率）为3（2017），4（2018）和5（2019）年（P <.05）。干物质产量的描述性较差，原因是复制之间的DMY差异很大。 与犹他州米尔维尔的Greenstar和Largo相比，AlkarXL的总DMY显着多（P <.10），而与犹他州Panguitch的Greenstar，Jose和Savarsi-1相似的DMY。