Table 3 Overview of scenarios and specifications

(1) Baseline [Bsl]

Adaptive expectations mechanism:

Growth expectation factor’s upper bound equals 2

Production reserve factor ranges between 1.2 and 1.5

(2) Stepwise phasing out of derogations at the farm level to use organic seed and organic cultivars [Derog]

Same specifications as in Scenario 1

Stepwise phasing out of derogations for NCT seed

Two-year steps: Year 2: 80% NCT seed allowed per farm, year 4: 50%, year 6: 30%, year 8: 0%

(3) Condition “Higher germination rate” [HgermR]

Adaptive expectation mechanism:

Upper bound of growth expectation factor equals 3

Production reserve factor equals 1.5 as uncertainty is reduced

Multiplication level: Organic hybrid seed price 1 Mio organic seed increases by 20%

Farm level: Germination rate increases by 20%, thus reducing the sown density from 2.4 Mio seed/ha to 2 Mio seed/ha

(4) Scenario 2 [Derog] + and 3 [HgermR]

No new specifications

(5) Scenario 4 [Derog, HgermR] + Condition “Sufficient organic seed” [SuffS]

The adaptive expectations mechanism of seed producers is relaxed to the extent that organic seed supply can meet organic seed demand: Growth expectation factor is calibrated to 3. At this value, there is no organic seed shortage for the 2-year stepwise phasing out of derogations, as proposed in Scenario 2

(6) Subsidy for organic seed and organic cultivars use related to cultivation area [Subs]

Same specifications as in Scenario 1

Different levels of subsidies at the farm level are tested. The goal of this process was to identify subsidy levels that induce farm agents to adopt organic seed and organic cultivars up to certain thresholds (e.g., up to the last adopter group)

(7) Organic carrot farm gate price premium per ton for organic seed and organic cultivar use at farm level [Prce]

Same specifications as in Scenario 1

Different levels of price premiums at the farm level are tested. The goal of this process was to identify price premium levels that induce farm agents to adopt organic seed and organic cultivars up to certain thresholds (e.g., up to the last adopter group)

(8) Scenarios 3 [HgermR] + 6 [Subs]

No new specifications

(9) Scenarios 3 [HgermR] + 7 [Prce]

No new specifications

(10) Scenario 8 [HgermR, Subs] + Condition “Sufficient organic seed” [SuffS]

No new specifications

(11) Scenario 10 [HgermR, Subs, SuffS] + 7 [Prce]

No new specifications