Introduction

The performance of grain sorghum hybrids is annually evaluated 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 grain sorghum 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 2018, 16 grain sorghum hybrids were entered by the commercial seed companies. Locations of these trials included the Central Research Station in Baton Rouge; Dean Lee Research and Extension Center in Alexandria; Red River Research Station in Bossier City; and Macon Ridge Research Station in Winnsboro (Table 1).

Suggestion for Selecting Hybrids

Most producers will agree that grain yield is the most important characteristic on which to base hybrid selection. The second characteristic to consider is maturity group. Grain sorghum maturity groups include early; medium/early; medium; medium/full; and full. The selection of hybrid maturity is usually based on available water for the season, whether through rainfall or irrigation. Hybrids that are high yielding in Louisiana are predominantly in the medium or medium/full maturity groups. Additional hybrid selection criteria include lodging susceptibility, weathering, plant height, test weight, stay-green, head exertion, panicle or head type, tolerance to sugar cane aphids, greenbug resistance and disease resistance.

In summary, review the results from all the trials that you can find that are relevant to your farming location and look for hybrids that have good, consistent results over years and locations. Do not rely on only one source of hybrid performance information. Plant two or more hybrids to spread out your risk. Place more value on replicated trials when comparing to strip trials.

Procedures

The experimental design at each location was a randomized complete block design with four or five replications. Grain sorghum variables measured and rating scales are listed in Table 2. Analysis of variance and least-significant differences (LSD) were calculated only if differences existed at the 90 percent confidence level. If differences were significant, an LSD at the 10 percent probability level was calculated. If the LSD (0.10) for yield in a trial is 10 bushels per acre, there is a 10 percent chance that two hybrids with a reported yield difference of 10 bushels per acre are genetically equal and a 90 percent probability they have a difference 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 percent 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 2018 across locations is summarized in Table 3. For each individual location, a summary of cultural practices, growing conditions, temperatures and rainfall is listed prior to the yield and agronomic data (Tables 4-7). Also, participating seed companies and their hybrid entries are listed in Table 8.

Grain Sorghum Hybrid Performance Trial, Central Research Station, Baton Rouge

Crop Summary

Grain yields ranged from 63.3 to 92.0 bushels per acre with a trial average of 81.97 bushels per acre (Table 4). There were 10 hybrids that fell within the high-yielding group for 2018. Anthracnose was observed, and ratings are included along with other agronomic data in Table 8.

Grain Sorghum Hybrid Performance Trial, Dean Lee Research Station, Alexandria

Crop Summary

During the months of May and June, rainfall was below normal, and temperatures were above normal (see graph below). Grain yields ranged from 92.7 bushels per acre to 125.6 bushels per acre with a trial average of 116.3 bushels per acre (Table 5). There were 13 hybrids that fell within the high-yielding group for 2018. Other agronomic data are presented in Table 5.

Grain Sorghum Hybrid Performance Trial, Red River Research Station, Bossier City

Crop Summary

During the months of May and June, rainfall was below normal, and temperatures were above normal (see graph below). Grain yields ranged from 45.2 bushels per acre to 81.4 bushels per acre with a trial average of 64.6 bushels per acre (Table 6). There were nine hybrids that fell within the high-yielding group for 2018. Yields were impacted by birds feeding on the heads. Bird damage ratings and other agronomic data are presented in Table 6.

Grain Sorghum Hybrid Performance Trial, Macon Ridge Research Station, Winnsboro

Crop Summary

During the months of May and June, rainfall was below normal, and temperatures were above normal (see graph below). Grain yields ranged from 41.5 bushels per acre to 81.9 bushels per acre with a trial average of 60.1 bushels per acre (Table 7). There were two hybrids that fell within the high-yielding group for 2018. Yields were impacted by birds feeding on the heads. Bird damage ratings and other agronomic data are presented in Table 7.