Smallholder Farmers’ Practices and African Indigenous Vegetables Affect Soil Microbial Biodiversity and Enzyme Activities in Lake Naivasha Basin, Kenya

Abstract

Loss of soil biodiversity and fertility in Sub-Saharan Africa (SSA) may put the food security of smallholder farmers in peril. Food systems in SSA are seeing the rise of African indigenous vegetables (AIVs) that are underexploited but locally consumed without being considered a primary source of food and income. Here we present a field study, a first of its kind, in which we investigated the effects of different cropping systems and inclusion of AIVs in the farming approach on bacterial and fungal biodiversity and community structures, enzymatic activity, and the alteration status of soils of the smallholder farmers in Kenya. When compared to mainstream farming approaches, the composition and biodiversity of bacteria and fungi under AIV cultivations was significantly different. Tillage had a significant impact only on the fungal communities. Fertilization and soil amendments caused shifts in microbial communities towards specialized degraders and revealed the introduction of specific microorganisms from amendments. Traditional homemade plant protection products did not cause any disturbance to either of soil bacteria or fungi. The soil alteration index based on enzyme activity successfully differentiated the alteration status for the first time in SSA. These findings could be useful for farmers to integrate AIVs with correct sustainable practices for a sustainable future.

Agronomical valorization of eluates from the industrial production of microorganisms: Chemical, microbiological, and ecotoxicological assessment of a novel putative biostimulant

“…The values indicate an overall low alteration state of the soil in all samples. The alteration index calculated was significantly lower (p < 0.05) at the eluate dosage of 40 g L −1 compared to the other treatments, showing a lower alteration state at this dose (Taskin et al, 2021). Enzymatic assays and the alteration index suggest that the soil enzymatic activity was not strongly influenced by the eluate application although an increasing trend in the enzymatic activities can be observed for all the enzymes tested.…”

LABs Fermentation Side-Product Positively Influences Rhizosphere and Plant Growth in Greenhouse Lettuce and Tomatoes

“…The following sets of primers were used: 343f (5 -TACGGRAGGCAGCAG-3 ) and 802r (5 -TACNVGGGTWTCTAATCC-3 ) and ITS-1 (5 -TCCGTAGGTGAACCTGCGG-3') and ITS-2 (5 -GCTGCGTTCTTCATCGATGC-3 ), for bacteria and fungi, respectively. Reaction conditions, concentrations, and thermocycling profiles were previously detailed in [15,17], and they were followed without further modifications. Two-step PCRs were performed independently for each sample as reported in [18,19].…”