F. Lopezgranados et L. Garciatorres, POPULATION-DYNAMICS OF CRENATE BROOMRAPE (OROBANCHE CRENATA) IN FABA BEAN (VICIA-FABA), Weed science, 41(4), 1993, pp. 563-567
Progression of crenate broomrape population density (PD, number of eme
rged plants m(-2)) in faba bean was studied over 8 yr in Spain. Spatia
l dispersion and effect of climatic conditions on parasite population
growth rate (PGR) also were studied. With repeated cropping of faba be
an, infestations of crenate broomrape increased from an initial PD of
0.15 to an average of 26, with a maximum of about 40 to 45. The averag
e population growth rate (PGR, ratio between the PD of any 2 consecuti
ve years) was approximately 3. However, this figure varied widely amon
g localities and years, from 0.8 to 7.7. A highly significant relation
ship (P = 0.01) was found between PGR and rainfall and soil temperatur
es during December to February, months of crop vegetative growth. Disp
ersion of crenate broomrape infestations mainly followed direction of
crop rows, most likely due to the effect of tillage and harvesting ope
rations, which were the same direction as sowing.