Data from: Combining ability of experimental maize lines for yield and aflatoxin in the southeastern USA
Data files
Jan 04, 2025 version files 356.81 KB
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Data_from_Knoll_et_al_2023.xlsx
353.96 KB
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README.md
2.84 KB
Abstract
Aflatoxin contamination of maize (Zea mays L.) grain presents risks to animal and human health and causes economic losses for growers, particularly in the southeastern United States. Development of hybrids with genetic resistance to aflatoxin contamination by Aspergillus flavus will reduce these risks. Two factorial crossing experiments were conducted to evaluate yield, agronomic traits, and aflatoxin in maize hybrids. In Exp. 1, 18 aflatoxin-resistant (GT) lines were each crossed to six testers. In Exp. 2, 13 of the same lines were each crossed to 10 different testers. Each experiment was conducted for two years at Tifton, GA and commercial check hybrids were included for comparison. Ears were inoculated with A. flavus isolate NRRL 3357 using the side-needle technique 14 d after silking. Aflatoxin was quantified after harvest. Broad sense heritability for aflatoxin was low in Exp. 1 (H2 = 0.09) but was higher in Exp. 2 (H2 = 0.27). Heritability was moderate to high for plant height (H2 = 0.49–0.51) and days to silking (H2 = 0.54–0.72). Among experimental lines, GT1209 and GT1309 had consistent positive general combining ability (GCA) for yield, whereas GT1203 and GT1204 had consistent negative (favorable) GCA for aflatoxin. Significant GCA effects, both positive and negative, for aflatoxin were also observed among testers in both experiments. Some experimental hybrids had yields that were comparable to commercial checks while also having lower aflatoxin, demonstrating the progress made in improvement of both traits in maize hybrids adapted to the Southern United States.
README: Data from Combining Ability of Experimental Maize Lines for Yield and Aflatoxin in the Southeastern USA
This dataset contains all raw data from all four years of the study in Excel (.xlsx) format.
Missing data are represented by a dash (-). Male and female parents of commercial hybrids are unknown and are thus coded as missing data.
Description of the data and file structure
Data from each individual experiment are presented in individual tabs. In 2014 and 2015, two separate experiments for yield (tabs 2014yld and 2015yld, respectively) and aflatoxin (tabs 2014afla and 2015afla, respectively) were conducted. Other agronomic traits, such as plant height, ear height, etc. were assessed in the 2014 and 2015 yield trials and are available in the 2014yld and 2015yld tabs. In 2018 and 2019, yield and aflatoxin were assessed within the same experiment along with other agronomic traits. These data are available in tabs 2018all and 2019all.
Data are reported under the following column headings:
- Plot_ID Unique plot number assigned within a year.
- Rep Replication number. Each experiment contained four replications.
- Range and Row. The unique position of each plot within the field can be defined by these two coordinates.
- Entry# - Unique number assigned to each pedigree within a year.
- Pedigree Pedigree for each specific entry or commercial name for checks.
- P_female Female parent
- P_male Male parent
- Stand Number of plants in the two-row plot. 72 seeds were planted in each plot.
- Ear_ht Height (cm) from ground to node of the primary ear
- Plant_ht Height (cm) from ground to tip of the tassel
- EP_Ratio Ratio of ear height to plant height
- Anthesis Days from planting until 50% of anthers are shedding pollen
- Silk Days from planting until 50% of silks are exposed
- ASI Anthesis-silking interval days between anthesis and silking
- %*Moisture Grain moisture at harvest as measured by the combine
- Plot_Wt_lbs Raw plot weight (lbs) of grain as measured by the combine
- TWT* lbs/bu Grain test weight (lbs/bu) as measured by the combine
- kg_ha_15 Grain yield in kg/ha adjusted to 15% moisture
- Lodging Total number of lodged plants. In 2018 and 2019, stalk lodging and root lodging were counted separately.
- %_lodging Total percentage of lodged plants
- 5_ears_g In 2018 and 2019, the shelled weight (g) of the five ears sampled for aflatoxin analysis
- 5_ears_lbs - In 2018 and 2019, the shelled weight (lbs) of the five ears sampled for aflatoxin analysis
- Plot_total_lbs In 2018 and 2019, the total weight of grain harvested from the plot (combine wt. + shelled ears)
- Afla_ppb Grain aflatoxin concentration (ppb, or ng/g) determined by the Vicam Aflatest procedure
- Log_afla+1 Aflatoxin concentration log-transformed as y = log(x + 1)