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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 andWashington. 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.

Dry bean (Phaseolus vulgaris L.) is a nutrient‐dense food rich in proteins and minerals. Although a dietary staple in numerous regions, including Eastern and Southern Africa, greater utilization is limited by its long cooking time as compared with other staple foods. A fivefold genetic variability for cooking time has been identified for P. vulgaris, and to effectively incorporate the cooking time trait into bean breeding programs, knowledge of how genotypes behave across diverse environments is essential. Fourteen bean genotypes selected from market classes important to global consumers (yellow, cranberry, light red kidney, red mottled, and brown) were grown in 10 to 15 environments (combinations of locations, years, and treatments), and their cooking times were measured when either presoaked or unsoaked prior to boiling. The 15 environments included locations in North America, the Caribbean, and Eastern and Southern Africa that are used extensively for dry bean breeding. The cooking times of the 14 presoaked dry bean genotypes ranged from 16 to 156 min, with a mean of 86 min across the 15 production environments. The cooking times of the 14 dry bean genotypes left unsoaked ranged from 77 to 381 min, with a mean cooking time of 113 min. The heritability of the presoaked cooking time was very high (98%) and moderately high for the unsoaked cooking time (~60%). The genotypic cooking time patterns were stable across environments. There was a positive correlation between the presoaked and unsoaked cooking times (r = .64, p < 0.0001), and two of the fastest cooking genotypes when presoaked were also the fastest cooking genotypes when unsoaked (G1, Cebo, yellow bean; and G4, G23086, cranberry bean). Given the sufficient genetic diversity found, limited crossover Genotype × Environment interactions, and high heritability for cooking time, it is feasible to develop fast cooking dry bean varieties without the need for extensive testing across environments.

Dry beans (Phaseolus vulgaris L.) are a nutrient dense food produced globally as a major pulse crop for direct human consumption. Despite being rich in protein and micronutrients, long cooking times limit the use of dry beans worldwide, especially in regions relying on wood and charcoal as the primary sources of fuel for cooking, such as Sub-Sahara Africa and the Caribbean. Coincidently, these same regions also have high densities of women and children at risk for micronutrient deficiencies [1]. There is need for a fast cooking bean, which can positively impact consumers by reducing fuel cost and preparation time, while simultaneously complementing the nutritional quality of house-hold based meals [2]. To help accelerate a reliable increase in dry bean production for Sub-Saharan Africa, the Andean Bean Diversity Panel (ADP; http://arsftfbean.uprm.edu/bean/) was assembled as a genetic resource in the development of fast cooking, nutritional improved, biotic/abiotic resistant varieties. A germplasm screening for atmospheric cooking time (100oC) of over 200 bean accessions from the ADP identified only five fast cooking entries [3]. Two entries were white beans from Burundi (Blanco Fanesquero) and Ecuador (PI527521). Native to Chile, two of the six fast cooking entries were collected from Angola, and had a pale lemon ‘Manteca’ yellow seed color (Cebo, Mantega Blanca). Traditional knowledge from Chile suggests Manteca yellow beans are low flatulence and easy to digest [4]. Yellow beans of various shades are important in Eastern and Southern Africa. Their popularity has increased in recent years and they often fetch the highest prices at the marketplace. There is evidence to suggest that Manteca yellow beans have a unique nutritional profile when compared to other yellow seed types; with more soluble dietary fiber, less indigestible protein and starch, and are also free of condensed tannins. The hypothesis was tested that this unique composition would also have a positive

INTRODUCTION - Cooking time and sensory quality are two important traits when selecting dry beans for consumption, but have largely been overlooked by breeders in favor of yield and other traits. Dry beans are an affordable, nutrient-rich food, but often require long cooking times, particularly without prior soaking. They also display a range of sensory characteristics, with consumers preferring cooked beans that are sweet and soft1. Increased interest in dry beans to make new products necessitates studies assessing the diversity of sensory traits in beans, which would allow beans to be selected for specific products. In this study, the Andean Diversity Panel2 (ADP) was assessed for cooking time and sensory characteristics in order to identify diversity for these traits. MATERIALS AND METHODS - Cooking Time Evaluation: 398 genotypes of the ADP were harvested in Hawassa, Ethiopia in 2015, six months prior to evaluation. Prior to cooking, each sample was soaked for 12 hours in 250 ml distilled water after ensuring moisture content was between 10-14%. Two replicates per genotype of 25 seeds each were cooked in random order in boiling distilled water using the Mattson cooker method for determining cooking time3. The Mattson cooker uses twenty-five 85g stainless steel rods with 2mm diameter pins that pierce beans loaded in wells when sufficiently cooked. For this study, the 50% and 80% cooking times were recorded, and the 80% cook time is regarded as the time required to cook each genotype to completion. The cooking time data was analyzed using the MIXED procedure in SAS with genotype as a fixed effect and rep as a random effect.