Date of Award
Master of Science - Agriculture
Dr. Michael Maurer
Dr. Jared Barnes
Dr. Josephine Taylor
Three experiments evaluated pinching and spacing on Helianthus annuus in East Texas to determine their effects on growth and development. Experiment 1 was designed to determine the effects of pinching nodes 1, 2, 3, or 4 on ‘Pro Cut Gold’ sunflowers. Results from experiment 1 showed non-pinched plants produced marketable stem lengths and flower sizes, while pinched plants’ stem length, stem diameter, flower diameter, and disk diameter decreased compared to the non-pinched plants. The objective for experiment 2 was to evaluate pinching and spacing treatments on ‘Pro Cut Gold’ sunflowers. All spacings for non-pinched plants in experiment 2 produced marketable stem lengths and flower sizes. Experiment 3 was designed to analyze the effects of pinching nodes 1, 2, 3, or 4 on ‘Pro Cut Gold, ‘Supreme Sunbright’, ‘Vincents Choice’, ‘Sunrich Lemon’, and ‘Superior Gold’ sunflowers. All of the non-pinched plants for all five cultivars produced marketable stem lengths and flower sizes. Pinching responses varied by cultivar but overall stem length, stem diameter, flower diameter, and disk diameter all decreased compared to the non-pinched plants. ‘Vincents Choice’ pinched at the first node was the only cultivar when pinched to produce a marketable stem length and flower size. A successful pinching in East Texas is dependent on planting early into the growing season (May). Spacing did not clearly affect sunflower growth and development; therefore, increasing planting densities of non-pinched sunflowers could increase marketable stem yield compared to pinching sunflowers at lower planting densities.
Burnett, Rebecca B., "Pinching and Spacing Effects on Cut Sunflower (Helianthus annuus) Production in East Texas" (2017). Electronic Theses and Dissertations. 121.
Tell us how this article helped you.