Evaluation of Ugandan cassava germplasm for drought tolerance
Turyagyenda, Laban F.
Kizito, Elizabeth B.
MetadataShow full item record
Increased pressure on prime arable land for agriculture to meet food demand for global population has resulted in shifting agriculture to marginal areas where drought is frequent. Focusing research towards development of drought tolerant varieties is thus necessary. Replicated field trials for farmer preferred cassava genotypes were established to evaluate their morphological and yield trait responses and adaptability to moisture stress. Results showed significant (P<0.05) differences among genotypes for all the parameters evaluated. Moisture stress resulted in a decline in Harvest Index by 22.34%, Fresh Root Yield by 37.04%, Number of Roots by 19.43%, Dry matter content by 16.58%, Root starch content of 20.81%, Leaf Retention by 25.72% and Plant height by 16.62%. Results therefore, evidently showed that water stress has significant devastating effects on vegetative and yield parameters of cassava. Breeding strategies to develop drought tolerant cassava varieties to cope up with increased water scarcity and semi-arid conditions are thus paramount. Varietal variability in response to water stress reported is a cornerstone in the breeding process. Besides genetic effects were dominant indicating breeding objectives would be easily achieved. Genotypes MH96/0686, Magana, Yellow, TME 204, Nyamutukura, MH97/2961, NASE 1, NASE 2 and NASE 12 were least affected by drought and may provide gene sources for cassava improvement. Genotype x Location was significant (P<0.05) suggesting that rational distribution of genotypes to agro-ecological zones with different levels of drought stress is possible. Some genotypes had stable yield and its components suggesting that cassava can easily adapt to dry environments