The effectiveness of local strains of Fusarium oxysporium f. Sp. Strigae to control Striga hermonthica on local maize in western Kenya

Abstract

Striga hermonthica weed infestation continues to persist among smallholder poor farmers in Kenya who depend on traditional maize (Zea mays L.) seeds for their livelihood. The purpose of this study was to evaluate the efficacy of five local Fusarium oxysporum f. sp. Strigae strains (FK1, FK2, FK3, FK4, and FK5) to control Striga on susceptible local maize cultivar “Rachar” in three farmer field sites in Siaya County, Kenya. A complete randomized block design was used in each site. Statistical analysis was done using SAS 9.1 software, and means for different strains were tested with Fisher's LSD. The strains differentially reduced the number of emerged Striga and infected most of the emerged Striga, which affected performance of the local maize. Striga emergence and infection rates were significantly different (p < .05) between different strains of F. oxysporum f. sp. strigae. FK1 and FK2 strains had the least pathogenicity, while FK5 strain had the highest pathogenicity on Striga. Soil and climatic factors influenced the rate of infection for the tested strains and maize performance. Improvement in yield during the short rains was attributed to the persistence of Fusarium strains in the soil. Based on Striga emergence and infection rates, and maize yield, FK5 was the most effective strain to curb Striga menace. Adoption of local F. oxysporum strains will increase maize yield in Siaya County's Striga‐infested fields from a dismal average of 0.95 t/ha to about 1.95 t/ha. The observed significant differences in the tested strains between sites for the infection and emergence rates revealed the importance of considering pathogens on a field‐to‐field basis. Further studies should be carried out to establish the relationship between soil properties and the five fungal strains.

Characterization of Maize Genotypes (Zea mays L.) for Resistance to Striga asiatica and S. hermonthica and Compatibility with Fusarium oxysporum f. sp. strigae (FOS) in Tanzania

“…The present study noted some cases where there were few or zero emerged Striga plants, as well as wilting of emerged Striga plants in some of FOS-treated pots, suggesting the efficacy of FOS in infecting Striga seeds, seedlings, and shoots. Comparable observations have been reported before in field and pot experiments involving maize and sorghum treated with FOS [10,70]. Some FOS-treated genotypes (TZA604, TZA3952, TZA4064 and JL01) under both Sh and Sa infestation supported an increased number of emerged Striga plants at eight and ten weeks after planting, suggesting FOS incompatibility.…”

Rhizobium-Linked Nutritional and Phytochemical Changes Under Multitrophic Functional Contexts in Sustainable Food Systems

“…However, non-pathogenic strains of the previously mentioned fungi with plant growth promoting effects have been isolated from leguminous root nodules of faba bean (Vicia faba) (Omar and Abd-Alla, 2000). While currently there is scarcity of published works on pathogenic endophytic fungi infection of leguminous root nodules, establishment of host range, and non-pathogenicity of some endophytic fungi remains a contentious subject (Ochieno, 2010(Ochieno, , 2020Avedi et al, 2014;Zarafi et al, 2015;Oula et al, 2020). Root endoparasitic nematodes are pathogenic microinvertebrates that exploit resources from rhizobium-legume symbioses (Taha, 1993;Weerasinghe et al, 2005).…”

A microbial bioherbicide for Striga hermonthica control: production, development, and effectiveness of a seed coating agent

“…28 Thirdly, the way in which the spore powder was bound to the maize seed could have played a role. While earlier experiments used almost exclusively Arabic gum 12,14,16 as the glue, the new spore powder was attached to the seed using a 10% sugar solution. This sugar solution offers the very rapidly developing Fusarium germs an ideal starter supply of nutrients.…”