Evaluation and differential expression of genes conferring drought tolerance in selected maize genotypes in the Morogoro Region of Tanzania
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Date
2018-06-26
Journal Title
Journal ISSN
Volume Title
Publisher
African Journal of Agricultural Research
Abstract
Experiments were conducted at Sokoine University of Agriculture in Morogoro, Tanzania to assess the
growth performance and grain yield of ten maize cultivars under well-watered and water stressed
conditions. The ten cultivars (CML 444, CML395, CML539, WE 4107, WE 2112, WE 3102, WE 4112 and
WE 4116) obtained from Water Efficiency Maize for Africa (WEMA) project and two local market cultivars
(‘STAHA’ and ‘TMV1’) were grown in a Randomized Complete Block design with a 10×3 factorial
treatment arrangement and three replications. The three drought stress treatments were 50, 75 or 100%
of field capacity with 10 kpa (equivalent to field capacity) and 30 kpa (drought) using tensiometers.
Drought stress was initiated at vegetative stage (three weeks after emergence) for thirty days and
flowering stage (one week before to two weeks after flowering). Plant height, stem diameter, leaf length,
leaf width and chlorophyll content were measured at weekly intervals from two weeks after planting to
maturity. Days to anthesis and silking were used to calculate Anthesis-Silking Interval (ASI) and kernel
dry mass were recorded at harvest. Vegetative growth responses were not affected by water stress, but
plant height and leaf chlorophyll content tended to decrease, while ASI ranging from 5.2 to 11.1 days
and kernel dry mass decreased with increased drought stress. Dry kernel weight was significantly
greater among five of the cultivars designated drought tolerant and the lowest in the two drought
susceptible cultivars. Drought tolerant genes were expressed at different levels and only a few cultivars
expressed all three genes at the vegetative and flowering stages. Thus, vegetative response of maize to
drought stress varied based on cultivars. However, it appears that drought stress exerted more impacts
on reproductive processes compared to vegetative.
Description
Full Length Research Paper
Keywords
Cultivars, Drought, Genotypes, Grain yield, Growth performance, Hybrids
Citation
10.5897/AJAR2018.13253