Slow‐darkening (SD) pinto beans (Phaseolus vulgaris L.) possess a desirable new trait, conditioned by the recessive sd gene, that slows seed coat darkening under delayed harvest and under storage. The effect sd may have on performance needs investigation. We examined agronomic performance and cooking quality of SD pinto beans. There were 30 (15 SD and 15 regular darkening [RD]) recombinant inbred lines (RILs) from each of two biparental inbred populations. The 60 RILs were tested across three locations in North Dakota and Washington. In addition, advanced SD and RD pinto breeding lines were tested in trials from 2010 to 2012 and in 2018. Across 2010–2012 trials, the “early generation bred” SD pintos, as a group, had significantly lower emergence, increased lodging, less seed yield, and smaller seed size than the RD group. Conversely, in the 2018 trial, “recently bred” SD pinto breeding lines had competitive agronomic performance to RD lines for seed yield, reduced lodging, and increased emergence. Further research on cooking time is warranted given that SD RILs cooked 20% faster than the RD RILs in one population. Overall, SD pintos exhibited slightly better canning quality than RD pintos. Whether raw or cooked, SD pintos were much lighter in color than RD pintos, emphasizing the need to keep them separated as distinct market classes. Breeders should continue to focus on improving agronomic performance for emergence, lodging, seed yield, seed size, and canning quality of SD pinto beans.

中文翻译：

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变黑缓慢的斑豆的农艺性能和烹饪品质特征

慢速变种（SD）斑豆（Phaseolus vulgaris L.）具有理想的新性状，该性状由隐性sd基因调节，可延缓收获和贮藏条件下种皮的变黑。sd效果可能需要对性能进行调查。我们检查了SD斑豆的农艺性能和烹饪质量。来自两个双亲近交系种群的每一个有30个（15个SD和15个常规变暗[RD]）重组近交系（RIL）。在北达科他州和华盛顿州的三个地点对60个RIL进行了测试。此外，在2010年至2012年以及2018年的试验中测试了高级SD和RD斑豆繁殖系。在2010-2012年的整个试验中，“早期繁殖的” SD斑豆作为一组的出苗率大大降低，倒伏增加，但种子产量高，且种子大小比RD组小。相反，在2018年的试验中，“近代繁殖” SD斑豆育种系在种子产量，减少倒伏和增加出苗率方面与RD系相比具有竞争性农艺学性能。鉴于在一个人口中SD RIL的烹饪速度比RD RIL快20％，因此有必要对烹饪时间进行进一步研究。总体而言，SD斑豆的罐头质量比RD斑豆略好。不论是生熟的还是熟熟的，SD斑豆的颜色都比RD斑豆的颜色轻得多，强调需要将它们分开作为不同的市场类别。育种者应继续致力于改善农艺性状，以提高SD斑豆的出苗率，倒伏率，种子产量，种子大小和罐头质量。