Q.how much tassel contact with the silks is required
How much or how many particles of the tassel contact with the silks is required for full kernel population?
The tassel (male part) releases around 16-20 million specks of “sperm.” The maximum number of potential kernels (ovules) per row is determined a week or so prior to the emergence of the silk, with some reports of up to 1,000 potential ovules per ear.
Potential kernels per row are highly dependent on growing conditions prior to silking while actual kernels per ear are determined by conditions during and after silking.
These articles should help further answer your question: