I've asked my contact at
Advancing Eco Ag more than once for any and all research and/or even a single paper that specifically ties cobalt to arginine to no avail. Arginine being the one amino acid that John Kempf states unequivocally feeds the scab organism . . . but read on please. What I found on my ownsome to substantiate such discussion was research done back in the 1950s. Generational tie-ins like this are incredible when you think of the folks back then on much the same trail. Here's the endnote verbatim from
Mycorrhizal Planet that goes with that passage above:
A fascinating study from the 1950s revealed the
proclivity of scab fungi to feed on less-than-complete
proteins. The amino acids most preferred
were alanine, arginine, aspartic acid, glutamic
acid, glycine, and proline. “
Venturia inaequalis:
Amino Acids as Sources of Nitrogen” by R. L.
Pelletier and G. W. Keitt was originally published
in the
American Journal of Botany, vol. 41, no. 4,
in 1954. Research like this reveals generations of
thought go into finding wholesome answers . . .
eventually!
What I don't have are direct correlations to cobalt (or any other trace mineral for that matter) that serves as a specific enzyme cofactor involved with protein synthesis that thwarts scab disease. True enough, I went with that piece of the puzzle as being put forth by Advancing Eco Ag but it may not be cobalt alone. Which brings me to Mike's point about foliar isolates versus generalist cooking. Far more is going on the surface of a colonized leaf than mere absorption of this mineral or that mineral. In other words, arboreal biology is very much involved with mineralization and assimilation of an array of elements, and in particular endophytic fungi may play a key role as a carrier, much like mycorrhizal fungi do in the soil. What's important is getting soluble amino acids to embed as complete proteins in the cell membrane of the leaf and the fruit, and thus be no longer available as sustenance for the disease organism. That puts me in the camp willing to use the recommended rate for MicroPak or SeaCrop in the context of biological reinforcement over singular trace minerals. Both are fine ways to explore this avenue of thinking . . . I'm simply being clear that "michael's results" will be those of a generalist cook. Numerous companies offer trace mineral isolates for foliar application, and I tend to think recommended rates are reasonable starting points.
Bottom line: Researchers like R. L. Pelletier and G. W. Keitt back in the 1950s may have had a chemical motive in seeking to better understand preferred nitrogen sources of scab. Perhaps they even were working towards a stunning cobalt conclusion. Who knows? On the other hand, recognition of how complete protein synthesis is one of the keys to thwarting fungal disease has always been a difficult pill for reductionist scientists to swallow. Similarly, what Dow-funded university researcher today is going to look into how to drop use of all fungicides because plants know how to do "green health" far better than humans? Waiting to act (and I realize, Todd, that's not what you are saying) because no one else has proven a technique works should never hold us back. We growers are the wellspring of progressive holistic knowledge and each new season is our laboratory.
Lost Nation OrchardZone 4b in New Hampshire