Rice-Based Trichoderma Inocula Enhance Fruit Production of Cutleaf Groundcherry (Physalis angulata L.) in the Amazon

In Amazonian Spodosols, soil acidity and nutrient constraints limit the cultivation of cutleaf groundcherry. One sustainable alternative for cultivating this species is the use of Trichoderma inoculants, but studies on their use in this crop are scarce. This study evaluated whether rice-based inocula of Trichoderma harzianum (TH) CCB-LA101 and T. viride (TV) CCB-LA103 improved growth and fruit production of cutleaf groundcherry and whether the responses varied with the application dose. Plants were grown in a randomized complete block design with a 2 × 3 factorial arrangement: two Trichoderma species and three inoculum doses applied to the soil (0, 4, and 8 g plant−1; Trichoderma concentration of 3.2 × 109 CFU g−1). Species and dose affected fruit width, length, number, and yield, with TH more effective than TV at increasing fruit number and yield. The contrast between inoculated and non-inoculated plants was significant for all traits. The 8 g plant−1 dose significantly increased fruit number and yield by 22.8% and 17.7%, respectively, relative to the non-inoculated control, whereas fruit width and fruit length decreased by 8.3% and 7.3%, respectively. Considering the six treatment combinations, the 8 g plant−1 TH inoculum (TH8) was the only treatment to significantly increase fruit yield, with net returns for smallholders estimated at USD 1104.46 ha−1. Therefore, under the tested conditions, TH8 could be used to grow cutleaf groundcherry in Amazonian Spodosols.