Date of Award
Spring 5-15-2018
Degree Type
Thesis
Degree Name
Master of Science - Agriculture
Department
Agriculture
First Advisor
Michael Maurer
Second Advisor
Jared Barnes
Third Advisor
Josephine Taylor
Abstract
Helianthus annuus cultivars were grown in East Texas to evaluate the effect of pinching and spacing on their growth and development. The first experiment was conducted twice (Trial 1A, 28 April 2017 and Trial 1B, 3 August 2017) to evaluate the effect of pinching at nodes 1, 2, 3, and 4 on sunflower cultivars ‘Superior Gold’, ‘Pro Cut Gold’, ‘Sun Bright Supreme’, ‘Vincent’s Choice’, and ‘Sunrich Lemon’. For trial 1A, all the non-pinched treatments for the five cultivars produced marketable stem lengths, stem diameters, flower diameters, and disk diameters. For the cultivar ‘Superior Gold’ all the treatments produced marketable stems. Only the pinching treatment at node 4 failed to produce marketable stems for the cultivars ‘Sun Bright Supreme’, ‘Vincent’s Choice’, and ‘Pro Cut Gold’. Only the non-pinched and pinching treatment at node 1 produced marketable stems for ‘Sunrich Lemon’. For trial 1B, all the non-pinched treatments for the five cultivars produced marketable stem lengths, stem diameters, flower diameters, and disk diameters. All the treatments of ‘Superior Gold’ produced marketable stems. The pinching treatment at nodes 2 and 3 produced marketable stems for ‘Vincent’s Choice’ sunflowers. Only the pinching treatment at node 1 failed to produce a marketable stem for ‘Sun Bright Supreme’ sunflowers whereas ‘Pro Cut Gold’ did not produce marketable stems when pinched at nodes 1 and 3. Only the pinching treatment at node 3 failed to produce marketable stems for the cultivar ‘Sunrich Lemon’. Trial 1A was successful in producing marketable stems for all the above mentioned cultivars except the cultivar ‘Sunrich Lemon’ whereas trial 1B failed to produce marketable stems for multiple cultivars. These results indicate that the success of pinching depends on the season of growing sunflowers. In East Texas, pinching was successful when it was done in the spring (late April) whereas the success of pinching decreased when it was performed in late summer (August). The second experiment evaluated the effect of spacing on the sunflower cultivars ‘Superior Gold’, ‘Pro Cut Gold’, and ‘Sunrich Lemon’. The spacing treatments were 30 × 30 cm, 23 × 23 cm, 15 × 15 cm, and 8 × 15 cm. All three cultivars successfully produced marketable stem lengths and flower diameters. The cultivar ‘Superior Gold’ produced marketable sunflowers for all the spacing treatments whereas ‘Pro Cut Gold’ produced marketable sunflowers for the 15 × 15 and 8 × 15 cm spacing treatments. The cultivar ‘Sunrich Lemon’ failed to produce marketable stem diameter and disk diameter for all the four spacing treatments. These results indicate that spacing treatments affect sunflower development. High plant density was successful for ‘Superior Gold’ and ‘Pro Cut Gold’, but high density planting was not successful for the cultivar ‘Sunrich Lemon’ during late summer.
Repository Citation
Cheema, Bilawal Irshad, "EFFECT OF PINCHING AND SPACING ON THE GROWTH AND DEVELOPMENT OF SUNFLOWERS (HELIANTHUS ANNUUS) IN EAST TEXAS" (2018). Electronic Theses and Dissertations. 179.
https://scholarworks.sfasu.edu/etds/179
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
