Probably you can cut 20 pistils and measure it with a mg scale (see attached picture), and then find out how many of them you need to make 1 gram of sample.

For example, if 20 pistils = 5 mg, and you need 1 g (1000 mg), then you need 4,000 pistils. That is a lot of labor to collect them........

Dear Sir, thank you for the detailed answer. The problem is that at the time of the flowering I need the sampling protocol ready. I found it useful to know the average weight or the number of pistils in one gram in order to plan the trial setup. I need an answer from anyone who has already done apple pistil sampling for the analysis.

Regards

But, cannot you figure out this on your apple variety using the method mentioned above, because differ apple variety, the resulting numbers of pistils may be different.

no