Simulation of the Seed Bank Dynamics of Orobanche crenata Forsk. in some Crop Rotations Common in Northern Syria

Abstract

Simulations of the dynamics of the seed bank of Orobanche crenata Forsk. under different crop rotations are presented. Rotations studied involved four host species, lentil (Lens culinaris Medik.), chickpea (Cicer arietinum L.), faba bean (Vicia faba L.) and woolly-pod vetch (Vicia villosa subsp. dasycarpa (Ten.) Cavill.), and non-host species. Simulation showed that the Orobanche seed bank dynamics in three-course crop rotations would result in a high Orobanche seed population and hence in low yields of the respective crops. Replacing the susceptible by resistant legumes such as woolly-pod vetch in some of the cycles of the rotations would keep the Orobanche infestation at a low level without reducing the proportion of legumes. A three-course crop rotation with faba bean would have to be changed to a 12-coursc rotation in which faba bean was grown every twelfth year but was replaced by woolly-pod vetch or other resistant legumes in seasons 3, 6, 9; 15, 18, 21; and so on. In the three-course rotations with chickpea or lentil, these susceptible legumes would be grown every ninth year but would have to be replaced in seasons 3 and 6; 12 and 15; 21 and 24; and so on, thus changing these three-course rotations into nine-course rotations.