I decided to evaluate a few kinds of plants for potential use in an experiment to run with my bio classes--the objective is to have students make predictions based on a model that beneficial microbes have a positive effect on plant growth, and then to set up an appropriate experiment and evaluate the results. I have been trying different combinations of plants and myco and/or beneficial bacteria preparation and the results have been mixed.
I bought two new 72-cell starter trays and asked my instructional associate to fill one with Promix HP, and one with the same Promix HP that had been autoclaved (steam-sterilized, killing all microbes). Only she knew which tray was which. I planted each tray identically with each cell in a row of six getting two seeds of the same type. They got overhead water (tap) until germination, and bottom water thereafter with one dose of dilute fish emulsion about four weeks in. I rotated the trays and switched sides (right/left) weekly, and the trays stayed in the same spot in our greenhouse.
A few of the plants I chose had seed viability issues, but two of the rows with Capsicum--padróns (C. annuum) and rocoto (C. pubescens) germinated nicely. Here is where the plants are at six weeks.
The difference is definitely noticeable, and yes, I confirmed that the tray on the right was the one with the live (non-autoclaved) Promix. Here is a closer shot in which it's easier to see the pepper seedlings.
C. pubescens in the foreground and C. annuum behind.
So yeah, I think this supports the claim that the microbes in Promix actually do have a positive effect on early growth.
I bought two new 72-cell starter trays and asked my instructional associate to fill one with Promix HP, and one with the same Promix HP that had been autoclaved (steam-sterilized, killing all microbes). Only she knew which tray was which. I planted each tray identically with each cell in a row of six getting two seeds of the same type. They got overhead water (tap) until germination, and bottom water thereafter with one dose of dilute fish emulsion about four weeks in. I rotated the trays and switched sides (right/left) weekly, and the trays stayed in the same spot in our greenhouse.
A few of the plants I chose had seed viability issues, but two of the rows with Capsicum--padróns (C. annuum) and rocoto (C. pubescens) germinated nicely. Here is where the plants are at six weeks.
The difference is definitely noticeable, and yes, I confirmed that the tray on the right was the one with the live (non-autoclaved) Promix. Here is a closer shot in which it's easier to see the pepper seedlings.
C. pubescens in the foreground and C. annuum behind.
So yeah, I think this supports the claim that the microbes in Promix actually do have a positive effect on early growth.
