Positive yield response of eggplant (Solanum melongena L.) to inoculation with AM fungi produced on-farm

- Eggplant seedlings, inoculated with AM fungi, were outplanted at two vegetable farms.
- Inoculation Yield Response (IYR) was significant in two of three site years.
- IYR appeared not to be due to improved P nutrition in greenhouse phase.
- IYR was greater when indigenous AM fungus levels in the field were low.

Inoculation of vegetable seedlings with arbuscular mycorrhizal [AM] fungi during the greenhouse growth phase is both biologically and economically practical. Inocula may be purchased or produced on-farm. This work contrasted the fruit yield response of eggplant with and without inoculation with AM fungi produced on-farm at one farm in 2015 and two farms in 2016. Inoculation significantly increased the yield of fruit the first year by 18% despite no impact upon overall shoot growth measured at the end of the greenhouse period or at the end of the growing season. Inoculation resulted in an increase of one fruit per plant. There was no response in 2016 at one farm, but at the second farm, inoculation with AM fungi increased the yield of fruit 11% vs. that of seedlings receiving low P addition in the greenhouse and 6% vs. those receiving high P. Here, this response amounted to an increase of 1.3-1.5 fruit per plant. The response to inoculation appeared to be inversely related to the number of propagules of AM fungi in the indigenous community of the field soil. Routine use of inocula of AM fungi can increase the yield of eggplant with minimal change to the farmer's normal practices.