Characterization of grain sorghum for physiological and yield traits associated with drought tolerance
Year: 2009
Type: dissertation
Abstract: Grain sorghum (Sorghum bicolor L. Moench) is the fourth most important cereal crop grown throughout the semi-arid regions of the world.It is a staple food crop in Africa and Asia, while it is an important feed crop in the United States (US).More recently it is increasingly becoming important as a potential bioenergy feedstock crop around the world.The state of Kansas is the largest producer of grain sorghum in the US and contributes 40% of the total production.Drought is one of the major environmental factors limiting sorghum production in the semi-arid regions of the US, Asia and Africa.It is estimated that global crop losses due to drought stress exceed $10 billion annually.In crop production, drought stress can be classified into pre-or post-flowering.Even though the world collections of sorghum contain over 35,000 accessions, the genetic base currently used in breeding programs is very small (about 3%).Thus, it is important to identify diverse breeding lines for crop improvement.The diversity (association) panel consisting of 300 sorghum lines from all over the world was assembled for trait evaluation and association mapping.In this research these lines were grouped into the five major races (Figure 1) and 10 intermediate races of sorghum.The objectives of the research are to: (i) quantify the performance of the diversity panel under field conditions in Kansas, (ii) identify critical physiological traits affected by drought at both pre-and post-flowering stages of sorghum development, (iii) identify the most sensitive stage to drought stress during the reproductive phase of sorghum development and, (iv) test the feasibility of using a chlorophyll fluorescence assay (CVA) as a tool for identifying stay-green lines in grain sorghum during early stages of crop development.Field experiments were conducted in 2006 and 2007 in two
Author: Raymond N. Mutava
Language: English
Topic: Genetics and Plant Breeding
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: green
OpenAlex ID: W93727801