INFLUENCE OF 'TAPROOT' SIZE ON 'SEED' YIELD OF FLORENCE FENNEL (FOENICULUM VULGARE MILL. VAR. DULCE MILL.)
The experiment included twenty treatments obtained by the combination of two seedlings size at planting time (20 and 100 g) with roots pruned or not and taproots coming from "crowns" of five sizes: < 200; 201–400; 401–600; 601–800; 801–1000. Taproot thickness and weight were positively correlated with crown size and taproot thicknes with taproot weight.
Seed yield increased linearly by increasing the crown size; it was 1.0–1.3–1.6–1.9 and 2.4 t/ha respectively for crowns less than 200 g; 201–400; 401–600; 601–800; 801–1000 g. Seeds from heavier crown matured early. Pruning the root at planting was beneficial for the small seedlings; conversely yield was reduced of about 0.6 t/ha in the large seedlings. The weight of "1000 seeds" was about 4 g but increased linearly by increasing crown size. More heavy seeds were obtained by root pruning of small plants.
Stems and umbels per plant increased linearly by increasing the crown size. The number of umbels per stem was higher by root pruning in the small plants, but the reverse occurred with large plants. Yield of seeds per umbel was high in the central, first and second order of umbels, than a marked drop was observed. Seed size decrease linearly from central to successive order of umbels. Seed yield was positively correlated with both the number of stems and number of umbels per plant. The weight of "1000 seeds" was negatively correlated with the seed yield, seed per plant and the number of umbels per stem.