Work

Cereal-based solid-state production and storage stability of native Trichoderma harzianum isolates for biological control applications

Year: 2026

Type: article

Abstract: The effectiveness of Trichoderma -based biocontrol products depends on achieving high spore yields and maintaining viable propagules during storage. This study evaluated the effects of substrate type, isolate, and storage duration on spore production and viability of four Trichoderma harzianum isolates (BH10-2, KH5-1, MG7-2, and SH11-2) cultured on four cereal-based substrates: rice grain (RG), rice powder (RP), sorghum grain (SG), and sorghum powder (SP). The experiment was arranged in a factorial Completely Randomized Design (CRD) with three replications under laboratory conditions. Spore production was assessed 10 days after fermentation, while spore viability was determined after 30, 60, and 90 days of storage following a 7-day drying period. Colony-forming unit (CFU) data were log-transformed before analysis using two-way ANOVA for initial spore production and a linear mixed-effects model (LMM) for repeated measurements of spore viability during storage. Mean separation was performed using Tukey's HSD test at P ≤ 0.05. Initial spore production was significantly influenced by the interaction between isolate and substrate ( P < 0.05). Rice powder supported the highest spore production, with isolate BH10-2 producing the greatest spore yield (8.55 log CFU g −1 ), whereas isolate MG7-2 grown on sorghum grain recorded the lowest initial spore production (5.81 log CFU g −1 ). Spore viability was significantly affected by isolate, substrate, storage duration, and their interactions ( P < 0.05). Spore viability increased from Day 10 to Day 30, indicating continued sporulation during the early storage phase, before declining progressively through Days 60 and 90. Sorghum grain consistently maintained the highest spore viability during prolonged storage, particularly for isolate MG7-2, whereas rice powder exhibited the greatest reduction in viability after 90 days. Overall, the results demonstrate that substrate selection influences both initial sporulation and long-term storage stability of Trichoderma . The combination of isolate MG7-2 and sorghum grain showed the greatest potential for developing stable Trichoderma -based bioformulations suitable for sustainable biological control.

Source: Frontiers in Microbiology

DOI: 10.3389/fmicb.2026.1991071

Authors: Dieumerci Dramani Londjiringa, Faith Mabiki, Richard Madege

Institution: Sokoine University of Agriculture

Language: English

Topic: Agriculture, Plant Science, Crop Management

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: gold

Estimated APC paid: $3,801