AGRONOMIC AND PHYSIOLOGICAL CHARACTERS OF PEARL MILLET (PENNISETUM AMERICANUM L. K. SCHUM) GROWN UNDER A SPRINKLER IRRIGATION GRADIENT (DROUGHT, STRESS, INDEX).

Physiological and agronomic responses of two pearl millet (Pennisetum americanum L. K. Schum) parents and their hybrid were evaluated under different water levels on a Brazito sandy loam soil at Tucson, Arizona in 1983 and 1984. A line source sprinkler irrigation gradient was used to create the treatments. Soil moisture and physiological parameters were measured under field conditions at weekly intervals. Growth was analyzed every other week, while yield and yield components were evaluated at the end of the experiment. Harvest Index, drought tolerance index, and water use efficiency (WUE) were calculated. Percent crude protein of seeds was analyzed, and photosynthesis was measured in 1984 only. Regression analysis was used to compare the performance of the cultivars for stability. Water stress significantly affected all parameters measured, and the stress effects were more pronounced in 1983. There was no significant difference between entries at each water level for most parameters. Plant height, dry matter, and total leaf area decreased as watering level decreased. The leaf area of the hybrid was significantly higher at high water level in 1983. Firing ratio was increased significantly by stress in both seasons and was significantly lower for the male at low water level in 1983. Yield and yield components were reduced significantly by stress in both seasons, which was reflected in the reduced harvest index. Relative yield of dry matter was higher for the male in both seasons. The hybrid had the highest drought tolerance index in 1983, while the female had the highest drought tolerance index in 1984. WUE of dry matter increased with stress, while WUE of grain yield decreased with stress in both seasons. The significant reduction in transpiration was 57, 56 and 66% in 1983 and 45, 53, and 52% in 1984 for female, male, and hybrid respectively. Leaf diffusive resistance and leaf temperature were increased by water stress in both seasons. Stability regression analysis provided no adequate differentiation among cultivars. The percent crude protein (weight basis) was increased significantly by stress by 38, 43, and 28% in 1983 and by 47, 33, 46% for female, male, and hybrid, respectively.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Plant Sciences

Grantor dc:publisher

The University of Arizona.

Year dc:date.issued

1984

Author dc:creator

• IBRAHIM, YASSIN MOHMED.

Advisor dc:contributor.advisor

• Marcarian, Victoria

• Pearl millet -- Water requirements.
• Plants -- Water requirements.
• Irrigation.

Statement dc:rights

• Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.

Language dc:language.iso

en

Handle dc:identifier.uri

http://hdl.handle.net/10150/187830

OAI identifier oai:identifier

oai:repository.arizona.edu:10150/187830