Genotypic Yield Stability of Wild and Landrace Sorghum Species Under Drought Stress and Striga Infestation

Abstract

Recurring drought stress cycles and widespread striga (Striga hermonthica (Del.) Benth) infestations are two of the major constraints of sorghum production in sub-Saharan Africa (SSA) where they cause a crop loss of about 60 billion US dollars and affect a population of about 100 M people annually. Plant breeders continue to employ conventional and molecular crop breeding strategies in the search for durable genetic resistance/tolerance mechanisms or for germplasm with genes against these two constraints. Crop wild relatives and landraces remain valuable resources of resistance/tolerance genes and have been utilized in the past to improve tolerance to drought stress and resistance to striga. The aim of this study was to assess the stability of performance of 64 sorghum wild relatives, landraces and progenies from some generation of crosses under striga infested and drought stress conditions in agroecological environments endemic for these two stresses. The performance of the genotypes under drought stress was assessed in well-watered and in water stressed conditions at the Kenya Agricultural Livestock Research Organization (KALRO) Kiboko Research Centre whereas the same set was evaluated under striga artificially infested field and potted trials at the KALRO Alupe Research Centre during 2018/2019 rainy seasons. Genotypes, B35 × ICSV III N, Macia, N13, ICSV 111 IN, F6YQ212 × B35, SRN39, GENO47293, ICSV 111 IN × B35, IS9830, Framida, GENO 45827, F6YQ212, B35 × AKUOR ACHOT were found to maintain stable high yields in both striga and drought conditions. The results here, showed that Genotype, Genotype × Environment (GGE) interaction partitioned genotypes in two of the four mega-environments according to their stability and mean grain yield (GY) and identified representative genotypes of the two traits that could be exploited to develop superior sorghum varieties adapted to drought and striga prone environments.

Host Resistance to Parasitic Plants—Current Knowledge and Future Perspectives

“…This is neither a new nor a complicated approach, but it gives relatively good results, as reported for Striga -resistant sorghum [ 30 ], maize [ 108 ], and O. cumana -resistant sunflower [ 109 ]. Furthermore, wild relatives of crop plants are often screened for resistance and resistance-defining genes with putative application in development of parasite-resistant hybrids [ 110 , 111 , 112 ] and such approaches are getting more and more efficient with the development of high-throughput analytical technologies. Overall, this topic is extremely wide and extensively studied, especially in crop plants susceptible to root parasitic plants.…”

“…Overall, this topic is extremely wide and extensively studied, especially in crop plants susceptible to root parasitic plants. Just like multiple stress tolerance, however, an important issue here is to combine parasitic-resistant traits with other beneficial features, such as high yield, which is addressed in several studies [ 111 , 113 ].…”

“…However, little is known about how these resistant genotypes evolved. In most plants, wild varieties and/or relatives are an established source of genes, involved in parasitic plants resistance as in sunflower [ 110 ], maize [ 125 ], sorghum [ 111 ], and tomato [ 69 ]. Therefore, it must be expected that the cultivated varieties have lost this specific trait during the selection process.…”

Improving Drought Resistance by Introduction of the Proline Synthesis Gene P5CSA into Inbred Rice Lines as a New Genetic Resource for Breeding Programs

“…The range of organisms from bacteria to maize, shows a strong correlation between increased levels of cellular proline and survival under water-deprived and high-salinity conditions (Chakraborty and Roychoudhury 2022). Some positive evidence associating osmotic adjustment with biomass production or yield under drought stress has been reported for wheat (Mehmood et al 2020;Condorell et al 2022), sorghum (Wagaw 2019;Ngugi et al 2022), chickpeas (Singh et al 2021), Brassica species (Xiong and Ma 2022) and barley (Shrestha et al 2022).…”