Prior to the beginning of each marketing season, or as soon as possible thereafter, the commission shall establish assessment rates for the marketing season, as follows: (

a) An annual assessment on producers of not less than one hundred dollars ($100) and not more than one thousand dollars ($1,000), as determined by the commission, based on the number of tons of winegrapes marketed during the preceding marketing season. (

b) In addition, producers shall pay an assessment not less than one dollar ($1) and not greater than twelve dollars ($12) per ton of winegrapes marketed by producers. In the discretion of the commission, the producer assessment may be established as a percent of the gross dollar value received by producers for winegrapes rather than on a per ton basis. The assessment shall be established on a sliding scale that decreases the assessment by two dollars ($2) per ton, or the percentage equivalent if the assessment is a percent of gross dollar value, for every tons of winegrapes marketed by producers in excess of tons. (

c) An annual assessment on vintners of not less than three hundred fifty dollars ($350) and not more than seven thousand five hundred dollars ($7,500), as determined by the commission, based on the number of tons of winegrapes processed and marketed by vintners during the preceding marketing season. (

d) In addition, vintners shall pay an assessment not less than one dollar ($1) and not greater than twelve dollars ($12) per ton of winegrapes processed by vintners for which an assessment has not already been paid by a producer. The assessment shall be established on a sliding scale that decreases the assessment by two dollars ($2) per ton for every tons of winegrapes processed by vintners in excess of tons. (

e) An assessment greater than the amount provided for in this

section may not be charged unless and until a greater amount is approved by a majority of the commission and by eligible producers and vintners pursuant to the referendum procedures specified in

Section 78903.