I was actually debating that this year after reading "Teaming With Microbes"
Heres a clip from a website about that,
There are two main categories of mycorrhizae relationships: Endomycorrhizal fungi (arbuscular mycorrhizal fungi) form relationships with over 90% of plants (including turf grasses). Ectomycorrhizal fungi form relationships with only about 2% of plants, but some of them are quite common.
Please note that there are a few plants that do not respond to either endo or ectomycorrhizal fungi, namely members of the brassica family (broccoli, Brussels sprouts, cabbage, cauliflower, collards, kale, and rutabaga); members of the Ericaceae family (rhododendron and azalea, blueberry, cranberry, heath and heather, huckleberry, lingonberry), as well as beets, mustard, spinach, and orchids.
And another from Ali's Organics
Using Soluble & Granular Mycorrhizae
Posted October 08, 2013
Using Mycorrhizae has some very important step to success. When used incorrectly, you can easily kill the beneficial fungi and bacteria.
First off, always look for a expiration date to insure you have a living product. Never except out of date products. They will still be viable for several months past their date, but they will degrade and you will need to use more with time. It best to use them up quickly before they become expired. Store Mycorrhizae in a cool place.
Soluble Mycorrhizae is not intended to apply to plants leaves. It should be used as a soil drench, diluted in clean (non-chlorine) water. Chlorine kills fungus and bacteria ! That's just what your Mycorrhizae is.
Granular Mycorrhizae can be added into each transplant hole of whatever plant, tree or shrub your are planting at the rate of 1/4 teaspoon for 1 gallon plants. It can also be added to seed beds as a general broadcast or directly in each trench.
When making compost tea add Mycorrhizae at the end of the brewing process just before drenching the soil. Mycorrhizae more than likely won't survive the brewing process. While compost tea is great sprayed on the leaves of plants, but only drench or spray the soil when you have added mycorrhizae in your tea.
Using synthetic fertilizers (especially fast-acting liquids) can harm microbial activity in the soil, which create fertilizer-dependent plants.
Soluble Mycorrhizae can be used as a seed soak. Generally using 1/4 teaspoon per gallon water, soaking up to 24 hours. This promotes rapid germination and root growth.
Spraying the drip line of established trees and shrubs or the root balls just before planting will boost the overall health of your long time investment.
Flowers and vegetables will have better production when using mycorrhizae. They also become more resilient to pest and diseases as well.
Mycorrhizae stimulates and energizes the living soil. Plants are able to take up water and nutrients better when there is mycorrhizal activity.
Mycorrhizae can be used on established plants, when planting transplants, or seed beds. It is great when added to potting soils.
Mycorrhizae needs the presence of roots for the spores to germinate and attach to, otherwise they will remain dormant in the soil.
Our opinion of tilling the soil will not harm microbes in the soil as long as you do not "over" till the soil. A slight "fluff" up once a year should be sufficient.