Author
ESTEVEZ DE JENSEN, CONSUELO - University Of Puerto Rico | |
Porch, Timothy - Tim | |
BEAVER, JAMES - University Of Puerto Rico |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 4/30/2017 Publication Date: N/A Citation: N/A Interpretive Summary: This study examined the biological nitrogen fixation (BNF) characteristics of 120 varieties in a trial of 118 common bean and two tepary bean lines. Inoculation with two BNF bacterial isolates, CIAT 899 and CIAT 632, was carried out in a screenhouse at the Juana Diaz Substation using sterilized sand in benches. Ten seeds per variety/line were sown in a completely randomized design with two replications. At five days after planting, seedlings were inoculated with a combination of both strains using 1 ml of inoculum at a concentration of 1 x 109 bacterial cells/ml. Nodulation parameters were evaluated 12 days after inoculation by counting the nodules the bacteria formed on the plant roots in the upper 3 cm of the roots. The distance to the crown of the nodule closest to the primary root was recorded. Varieties that produced more than 50 nodules in the upper 3 cm of the root were Zorro, Amadeus 77, ICA Pijao, PR9920-171, ICB 301-204, BFS 139, SEQ 342-39, FNB 1203-47, SEF 16, Paraisito, Zenith and PR1217-1. In the second trial, FNB 1203-43, PR 1217-1, BIOF 4-70 and INTA Precoz formed more than 50 nodules at 12 days after inoculation. In the third trial, significant differences were also found among the different varieties and 64 varieties outperformed the local check Verano. Varieties FNB 1210-48, BFS-29, BFS-139, ICA Pijao, BAT-477, and DOR 390 had over 60 nodules within the first 3 cm of the root. The trials identified varieties with the capacity to produce a large number of nodules located near the plant crown, which is a key characteristic of efficient nitrogen fixation. Thus, varieties have been identified with the potential for increased yield through BNF under low fertility soil conditions. Technical Abstract: This study examined the nodulation characteristics of the BASE 120 genotypes in a trial of 118 common bean (Phaseolus vulgaris L.) and two tepary bean (Phaseolus acutifolius) lines. Inoculation with Rhizobium tropici strain CIAT 899 and Rhizobium etli strain CIAT 632 was carried out in a screenhouse at the Juana Diaz Substation using sterilized sand in benches. Ten seeds per cultivar/line were sown in a completely randomized design with two replications. At five days after planting, seedlings were inoculated with a combination of both strains using 1 ml of inoculum at a concentration of 1 x 109 rhizobia cells/ml. Nodulation parameters were evaluated 12 days after inoculation by counting the nodules in the upper 3 cm of the roots. The distance to the crown of the nodule closest to the primary root was recorded. Genotypes that produced more than 50 nodules in the upper 3 cm of the root were Zorro, Amadeus 77, ICA Pijao, PR9920-171, ICB 301-204, BFS 139, SEQ 342-39, FNB 1203-47, SEF 16, Paraisito, Zenith and PR1217-1. In the second trial, FNB 1203-43, PR 1217-1, BIOF 4-70 and INTA Precoz formed more than 50 nodules at 12 days after inoculation. In the third trial, significant differences (P > 0.05) were also found among the different genotypes and 64 genotypes outperformed the local check Verano. Genotypes FNB 1210-48, BFS-29, BFS-139, ICA Pijao, BAT-477, and DOR 390 had over 60 nodules within the first 3 cm of the root. The trials identified genotypes with the capacity to produce a large number of nodules located near the plant crown, which is a key characteristic of efficient nitrogen fixation. |