QTL analysis of cooking time and quality traits in dry bean (Phaseolus vulgaris L.)

Authors: BERRY, MATTHEW - Michigan State University; IZQUIERDO, PAULO - Michigan State University; JEFFERY, HANNAH - Michigan State University; Shaw, Robert - Scott; NCHIMBI-MSOLLA, SUSAN - Sokoine University Of Agriculture; Cichy, Karen

Submitted to: Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/11/2020
Publication Date: 5/6/2020
Citation: Berry, M., Izquierdo, P., Jeffery, H., Shaw, R.S., Nchimbi-Msolla, S., Cichy, K.A. 2020. QTL analysis of cooking time and quality traits in dry bean (Phaseolus vulgaris L.). Theoretical and Applied Genetics. 133:2291-2305. https://doi.org/10.1007/s00122-020-03598-w.
DOI: https://doi.org/10.1007/s00122-020-03598-w

Interpretive Summary: Beans are dietary staple in Tanzania and cooking time is a major factor associated with consumer preference of dry beans. The genetic control of cooking time was investigated in a population of bean lines developed from a moderate cooking and a fast cooking bean line. The population was grown on research farms over two years in Arusha and Morogoro, Tanzania. Arusha is an important mid-altitude bean growing region, with moderate temperatures and reliable rainfall whereas the low-altitude and high temperatures in Morogoro make it unfavorable for bean production. The population exhibited large variation for cooking time with a range of 22 min to 98 min. On average, beans grown in Arusha cooked 15 min faster than those grown in Morogoro. Ten genomic regions associated with cooking time were identified and three were especially important in determining cooking times. Bean lines with all three of these genomic regions inherited from the fast cooking parent cooked on average 11 min faster in Arusha and 26 min faster in Morogoro than lines with none. Cooked seed protein concentration was evaluated as an indication of the nutritional value of the bean lines. Protein concentration ranged from 17.8 to 30.8 percent within the population. Faster cooking time was associated with increased protein concentration.

Technical Abstract: Cooking time is a major factor associated with consumer preference of dry beans (Phaseolus vulgaris L.). The genetic control of cooking time was investigated with a quantitative trait loci (QTL) study on a recombinant inbred line (RIL) population developed from TZ-27 (slow cooking) and TZ-37 (fast cooking). The RIL population of 146 lines was grown on research farms over two years in Arusha and Morogoro, Tanzania. Arusha is an important mid-altitude bean growing region, with moderate temperatures and reliable rainfall whereas the low-altitude and high temperatures in Morogoro make it unfavorable for bean production. The population exhibited large variation for cooking time with a range of 22 min to 98 min. On average, beans grown in Arusha cooked 15 min faster than those grown in Morogoro. A linkage map developed with 1,951 SNP markers was used for QTL analysis. Ten QTL were identified for cooking time, three of which were found in multiple environments. RILs with all three QTL (CT3.1, CT6.1, CT11.2) cooked on average 11 min faster in Arusha and 26 min faster in Morogoro than RILs with none. Seed attributes were related to cooking time such that seeds with greater seed mass and less seed coat percentage cooked faster. Cooked seed protein concentration ranged from 17.8 to 30.8 percent across the years and locations. All three of the most robust cooking time QTL co-localized with QTL for protein concentration and TZ-37 always contributed faster cooking time and increased protein concentration.