Liliana Florez-Palacios

Selection of High Inorganic Phosphorus-Low Stachyose Soybean Breeding Lines

Soybean (Glycine max [L.] Merr.) seed stachyose and phytic acid are not digested by monogastric animals, and thus represent an obstacle for an efficient utilization of soybean meal in animal feed. The objectives of this research were to select breeding lines with high inorganic phosphorus (Pi)/low stachyose, along with adequate levels of sucrose, from an F2:6 population derived from the cross S02-529 x V99-5089 and evaluate their yield potential and stability across environments. Sucrose distribution showed no distinctive pattern, whereas Pi and stachyose exhibited a bimodal distribution. Stachyose and Pi fit the expected 3:1 ratio for a one-gene model previously reported for the high-Pi/low-stachyose trait in V99-5089. The highest yielding line, R08-6023 (2894 kg ha−1), showed relatively low stability for yield across environments, but it would be an adequate choice for highly productive environments. R08-6009 (2634 kg ha−1) ranked fourth in yield but showed less yield fluctuations across environments than other lines studied. One selected line had moderately high oleic acid concentration (>45 mg g−1), and three other lines had low linolenic acid concentration (<34 mg g−1), which are unique combinations with the high-Pi/low-stachyose trait. Although relatively low in yield as compared to the commercial checks, these novel breeding lines would be useful in breeding programs in developing multiple-trait stacks of value when incorporated into high-yielding backgrounds.

Screening a Diverse Soybean Germplasm Collection for Reaction to Purple Seed Stain Caused by Cercospora kikuchii

Purple seed stain (PSS), caused by Cercospora kikuchii, is a prevalent soybean disease that causes latent seed infection, seed decay, purple seed discoloration, and overall quality deterioration. The objective of this research was to screen soybean accessions from the United States Department of Agriculture germplasm collection for resistance to PSS. In total, 123 plant introductions (PI) from 28 different countries, representing maturity groups (MG) III, IV, and V, were screened. Incidence of Cercospora leaf blight (% CLB), visual PSS (% PSS), and seed infected by C. kikuchii (% C. kikuchii) in harvested seed were determined. In 2007, % C. kikuchii was 2 to 51% for MG III, 2 to 35% for MG IV, and 0 to 33% for MG V. In 2008, % C. kikuchii was 0 to 45% for MG III, 1 to 71% for MG IV, and 0 to 15% for MG V. In total, four and ten PI from MG III and IV, respectively, were identified as resistant to PSS in both years. Highly positive correlations were found for inoculated versus noninoculated treatments and for % PSS versus % C. kikuchii infection. The PSS-resistant PI identified in this study will be valuable to breeders in developing resistant cultivars.

Field evaluation and break-even analysis of specialty soybeans for biodiesel and meal protein production

ABSTRACT The economic value of a soybean [Glycine max (L.) Merr.] crop depends on yield and quality. The objectives of this study were to evaluate soybean lines for protein and oil content and to examine the break-even (BE) analysis of these traits combined with yield. Forty lines of maturity group (MG) IV or V were grown at four Arkansas locations for two years. Yield, protein, and oil content of each line were determined and compared to the check average for a BE comparison of the total economic value of the line. Results showed six profitable lines (

Confirmation of SSR Markers and QTL for Seed Calcium Content and Hardness of Soybean

8.40 to

Agronomic evaluation of high-protein and high-oil soybean genotypes for specialty markets

54.96 per metric ton based on yield) in 2008 and six profitable lines (

A Simple Greenhouse Method for Screening Salt Tolerance in Soybean

0.49 to

Identification of Quantitative Trait Loci for Sucrose Content in Soybean Seed

61.19 per metric ton based on yield) in 2009. Overall, in both MG, high-protein lines needed to yield more to be profitable, whereas high-oil lines had competitive yield, protein and oil content; R00-764 (MG IV), R05-71 (MG V), and R02-6185F (MG V) were competitive without added premiums.

An effective field screening method for flood tolerance in soybean

ABSTRACT Seed calcium content and hardness constitute determining characteristics of soybean [Glycine max (L.) Merr.] texture affecting soyfood quality. Molecular markers linked to these traits will accelerate breeding of soybeans for the soyfood market through the use of marker-assisted selection (MAS). Confirmation of linked markers and validation of quantitative trait loci (QTL), prior to their application through MAS, are the keys. The objectives of this study were to confirm previously reported QTL for calcium content and seed hardness and investigate the relationship between these traits. Evaluation of seven recombinant inbred line (RIL) populations with different genetic backgrounds, grown in two Arkansas locations for 2 years, showed inconsistent correlations between these traits. In general, a positive correlation was found in most of the populations and correlation was significant in six populations. Combined data showed a positive correlation between calcium content and seed hardness (r = 0.23 – 0.49). Furthermore, previously reported QTL for calcium content and/or hardness were evaluated in six different sub-populations and stable markers across environments were identified for potential use in MAS. Based on our results, markers Satt267 and Sat_345 on chromosome 1, Sat_288 on chromosome 7, Sat_228, Satt341, and Sat_392 on chromosome 8, Satt547 on chromosome 16, and Satt002 on chromosome 17, are reliable for calcium content selection; whereas, Satt267, Satt680, Satt341, and Sct_010 on chromosomes 1, 7, 8, and 19, respectively, can be used for selection for seed hardness. Findings of this research will facilitate MAS for seed calcium content and hardness in breeding programs aimed at improving food-grade soybeans.

Registration of R10-5086 and R11-6870 Soybean Germplasm Lines with Exotic Pedigree

ABSTRACT Soybeans (Glycine max (L.) Merr.) are mainly grown for protein and oil purposes. The objectives of this study were to: 1) evaluate maturity group (MG) IV and V soybean genotypes for traits associated with local adaptability (yield, plant height, and maturity), and 2) determine seed protein and oil concentrations, their correlation with yield, and respective heritabilities. A total of 40 MG IV or V genotypes were evaluated in four Arkansas locations in 2008 and 2009. The results showed that the genotype x year x location effect was significant for all traits studied, except maturity. Protein and oil concentrations were negatively correlated (−0.91) and highly heritable (0.89–0.93 and 0.82–0.83, respectively). Four promising high-yielding genotypes with moderately high to high protein or oil levels were identified: R05-4682 (high protein) and R05-4256 (high oil) in the MG IV test, and R05-1772 (high protein) and R05-71 (high oil) in the MG V test. These genotypes could potentially bring added value to Arkansas farmers’ fields.