Excessive N and brix levels
Because I already hijacked another thread on this discussion I decided, at another person's suggestion, to start another thread. I realize this won't be of much interest to most of you.
A participant in this forum has often stated here that excessive nitrogen leads to more watery, lower brix (level of soluble solids)fruit, which was always my belief as well, until someone questioned me on the basis of my opinion.
At that time I found a couple pretty extensive studies that indicated that excess N did not affect brix levels in fruit but I was unable to locate those studies this time around. However I did find several that shows the issue is more complicated than brix levels.
While it may be correct that excessive N can damage fruit flavor, it is apparently not because of lower brix levels. Here's a quote from an English study I found in the ISHS library.
Fruit ground colour was greener and red colour poorer in high nitrogen than in low nitrogen fruit. The concentration of titratable acid sometimes was highest in fruit from low nitrogen plots. Moreover, decomposition of the acids seemed to progress more slowly in low nitrogen than in high nitrogen fruit. Soluble solids were not affected by nitrogen supply. There is a close negative relationship between colour and flavour. Thus the higher rates of nitrogen were reflected in the poorer flavour of the fruits.
Here's some other studies that generally indicate that brix levels are not affected by rate of N.
When I researched this last year, the studies I looked at only evaluated brix levels in relation to N and not the overall quality of the fruit. I mistakenly assumed that the two were synonomous.