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In Vietnam, drought is one of major constraints for maize production.
Consequently, damage caused by drought was estimated more than 30%, up to 70-
80% or no harvest at all. Vietnam is one of the most affected countries by climate
change and drought has been more and more regular and severe. Therefore, it is
annually about 0.6 and 0.7 million ha maize area facing more stresses especially
drought. Maize area, grain yield and production in Vietnam in 2017 was 4.6
tons.ha-1 respectively that it is lower than the global average (5.5 tons.ha-1).
Meanwhile, the demand becomes more and more, leading to exceeding the supply
Therefore, breeding drought tolerant maize varieties is the most important
orientation for rainfed maize areas. Therefore, it is essential for the thesis
“Agronomic traits associated with drought tolerance of tropical-derived
germplasm for hybrid maize breeding” for increasing an efficiency in breeding
gain may be crucial.
RESEARCH OBJECTIVES
Studies on agronomic traits associated with drought tolerant ability of some
materials were carried out for selection of inbred lines and development of
promising maize hybrids for production.
SCIENTIFIC AND PRACTICAL MEANINGS OF THE THESIS
- The meanings of science
Providing more and more scientific data on phenotyping and evaluating combining
ability of F2:3 BP progenies populations under managed drought and optimal
condition, in combination with identifying genome regions associated with
quantitative trait locus (QTLs) controlling drought tolerance at the early generations
during improvement and development of drought tolerant maize varieties.
- The meanings of practice
+ Based on the results of evaluating drought tolerance of 8 BP progenies at F2:3
generations [8 BP populations × testers] for selection and development of 9 inbred
lines with good combing ability and drought tolerance, high yield under drought
stress, higher efficiency in drought tolerant maize breeding.
+ Having identified 2 significant gene clusters, including the first on
chromosomes 1 (bin 1.05-1.07), 7 (bin 7.01-7.03) and the other on chromosome 8
(bin 8.02-8.03), controlling anthesis- ilking interval, leaf senescence and grain
yield relating to drought tolerance.
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