Daniel Fromme, Waltman, William F., Stapp, John, Mascagni, Jr., Henry J., Buckley, Blair, Brown, Sebe, Padgett, Guy B., Ezell, Dustin, oclark, Netterville, Melanie, Copes, Josh
The performance of corn hybrids is evaluated annually in the official variety trials (OVTs) by LSU AgCenter researchers. The purpose of these trials is to provide Louisiana growers, seedsmen, county agents and consultants with unbiased performance data for commercial corn hybrids submitted for evaluation by private companies. Selection of superior hybrids that are well adapted for a given region is essential for maximizing yield and profit. In 2019, 54 corn hybrids were entered by commercial seed companies. Locations of these trials included the Dean Lee Research and Extension Center, Alexandria; Red River Research Station, Bossier City; Northeast Research Station, St. Joseph; and Macon Ridge Research Station, Winnsboro (Table 1).
Table 1. Summary of corn hybrid trials by location, 2019.
|Location||Soil type||Irrigation||Row Spacing||Planting Date||Harvest Date|
|Alexandria||Coushatta silt loam||Nonirrigated||38”
|Bossier City||Caplis very find sandy loam||Nonirrigated||40”||3/21||8/30|
|St. Joseph||Commerce silt loam||Furrow||40”||3/20||8/22|
|St. Joseph||Sharkey clay||Furrow||40”||4/11||8/30|
|Winnsboro||Gigger silt loam||Furrow||40”||3/20||8/22|
Hybrid selection is one of the most important decisions a producer will make and is essential for successful corn production. Seed companies offer multiple hybrids for sale to producers for good reasons. Each corn producer has somewhat different soil conditions, irrigation practices and crop rotations than other growers located in their farming community. Some hybrids will tend to perform better than others based on soil type, planting date, environmental conditions and location.
Yield is important when selecting a corn hybrid; however, maturity, stay-green, lodging, shuck cover, ear placement, disease and insect resistance need to be considered. Yield data from multiple locations and years are good indicators of the consistency of a hybrid’s performance.
Hybrid maturity is rated using the relative maturity (RM) or growing degree day (GDD) rating systems. These two methods are based on the number of days or degree days for a hybrid to reach physiological maturity. Louisiana producers can grow early, midseason, and full-season hybrids. In Louisiana, 112-to-121-day maturity hybrids usually produce the best yields. Full-season hybrids do not consistently out yield midseason hybrids. It appears there is more variability in yield among hybrids within a given RM rating than there is between maturity groups.
Hybrids that stay green later into their maturity usually retain better stalk strength and have less lodging potential. Shuck cover is important for protecting the ear and kernels from weathering and fungi. At later planting dates, a corn hybrid will grow taller because of an increase in day and night temperatures causing the internodes of the stalks to be longer. Therefore, ear placement will be higher when compared to an earlier planting date. This usually means that the lodging potential will be greater. When planting late in the season, consider planting a hybrid that has a low ear placement.
Also, corn hybrids have different insect and herbicide traits. These biotechnology traits will be need to be considered and should be based on which one best fits into your production system.
Select several hybrids that are consistently top performers over multiple locations or years within a region. Consistency over multiple environments is important because we cannot predict next year’s growing conditions.
The experiment design at each location was a randomized complete block design with four or five replications. Corn variables measured and rating scales are listed in Table 2. Analyses of variance and least significant differences (LSD) were calculated only if differences existed at the 90% confidence level. If differences were significant, an LSD at the 10% probability level was calculated. If the LSD (0.10) for yield in a trial is 10 bushels per acre, there is a 10% chance that two hybrids with a reported yield difference of 10 bushels per acre are genetically equal and a 90% probability they have differences in genetic potential in that particular environment. LSD values are influenced by how well soil fertility, stand establishment, plot length, harvest efficiency and other variables are controlled and by number of replications for each hybrid. The letters NS are used in the text and tables to indicate lack of significance (not significantly different) at the 10% probability level. The coefficient of variation (CV) reflects the magnitude of experimental error (random variation not accounted for by hybrids and replications) in relation to the trial mean. A high CV means that relative differences among hybrids were not consistent among replications, which reduces the precision of the test.
Yield data for 2019 across locations and for two- and three-year averages across locations are summarized in Tables 3, 4 and 5 (see PDF). To be considered for a two- or three-year average, hybrids must have the same seed traits each year (refer to Table 11; see PDF). For each individual location, a summary of cultural practices, growing conditions, temperatures and rainfall is listed prior to the yield and agronomic data (Tables 6 to 10; see PDF). Seed traits and hybrid maturities are listed in Table 11 and a description for these traits is listed in Table 12 (see PDF). Participating seed companies and contact information can be found in Table 13 (see PDF).
Table 2. Corn performance variables measured for the LSU AgCenter Official Variety Trials, 2019.
|Yield||YLD||Grain yield, bu/a, @ 15.5% harvest grain moisture|
|Grain moisture||GM||Grain moisture at harvest, %|
|Test weight||Test wt||Volume weight of grain, lb/bu|
|Plant population||Stand||Number of plants at harvest, plt/a|
|Midsilking date||MS||Date of silk emergence in 50% of plants in plots, days after planting (DAP)|
|Plant height||PH||Height from ground to the flag leaf, inches (in)|
|Ear height||EH||Height from ground to where primary ear attaches to the plant, inches (in)|
|Husk cover||HC||Measure how well the kernels are covered by the husk, with ratings of 1-3; 1=closed and 3=open husk|
|Lodging||LO||Percent of plants that are lodged at harvest|
Soil moisture conditions were very good at planting and throughout the months of April and May. Temperatures were moderate during the month of June, which coincided with pollination and early grain fill. However, during the month of June, rainfall was below normal (see graph below). Grain yields ranged from 187.8 to 247.4 bushels per acre with a trial average of 222.16 bushels per acre in this dryland trial (Table 6; see PDF). Yield results were considered excellent for this part of the state. There were 25 hybrids that fell within the high-yielding group for 2019. Other agronomic data are presented in Table 6.
During the months of June and July, rainfall was below normal, causing yields to be reduced (see graph below). Temperatures were moderate during the months of June and July, which coincided with pollination and grain fill. Grain yields ranged from 103.0 to 154.1 bushels per acre with a trial average of 124.1 bushels per acre in this dryland trial (Table 7; see PDF). There were 12 hybrids that fell within the high-yielding group for 2019. Other agronomic data are presented in Table 7.
Cool temperatures were experienced during March and April with soil moisture being adequate. Temperatures were moderate in May with adequate rainfall. June rainfall was adequate, which coincided with pollination and a large portion of grain fill (see graph below). Grain yields ranged from 161.7 to 275.7 bushels per acre with a trial average of 253.8 bushels per acre in this irrigated trial (Table 8; see PDF). Excellent yields were produced at this location. There were 39 hybrids that fell within the high-yielding group for 2019. Other agronomic data are presented in Table 8.
Cool temperatures were experienced during April with soil moisture being adequate. Temperatures were moderate in May with adequate rainfall. June rainfall was adequate, which coincided with pollination and a large portion of grain fill (see graph below). Grain yields ranged from 157.2 to 224.3 bushels per acre with a trial average of 202.0 bushels per acre in this irrigated trial (Table 9; see PDF). There were 22 hybrids that fell within the high-yielding group for 2018. Other agronomic data are presented in Table 9.
Cool temperatures were experienced during March and April with soil moisture being adequate. Temperatures were moderate in the month of May and there was adequate rainfall. During the months of June and July, rainfall was below normal, which coincided with grain fill (see graph below). Grain yields ranged from 197.5 to 227.43 bushels per acre with a trial average of 207.48 bushels per acre in this irrigated trial (Table 10; see PDF). There were 13 hybrids that fell within the high-yielding group for 2019. Other agronomic data are presented in Table 10.
Soil type: Gigger silt loam