Developing Dryland Corn Production Systems in West Texas.

Dryland corn in west Texas is gaining interest by producers and industry due to yield potential compared to alternative grain crops, availability of herbicide and insect protection traits and better marketing opportunities. Less than optimum in-season rainfall has resulted in interest in plant populations well below recommended populations used in other dryland regions. Replicated field studies were installed at five locations in the southern High Plains of Texas under dryland conditions during 2017. Seed rate treatments evaluated include 19,760, 27,170, 34,580, 41,990 and 49,400 seeds per acre for two corn hybrids with varying maturity (95 and 105 RM). All plots were planted by commercial equipment and planters were split between the two hybrids. Plots were 8 rows wide with row spacing common (76.2-cm) to the region and from 91 to 381 m in length. All other crop inputs (including herbicides, fertilizers, pest and disease control) were applied at the discretion of the producer. At each location prior to harvest, plant stand (population) will be measured at harvest and yield components measured by hand harvesting all ears from 10 consecutive plants in each plot. Ears will be counted and primary ears measured to determine average kernel rows, kernels per row, kernel size and ear and kernel weight. Plot yield will be determined using weigh wagon or yield monitor. Yields will be corrected to 15.5% moisture. Regression analysis will be used to identify optimum seeding rates.