SHORT-TERM AND LONG-TERM ECONOMIC-IMPLICATIONS OF CONTROLLING CRENATEBROOMRAPE (OROBANCHE-CRENATA FORSK.) IN BROAD BEAN (VICIA-FABA L.) UNDER VARIOUS MANAGEMENT STRATEGIES
F. Lopezgranados et L. Garciatorres, SHORT-TERM AND LONG-TERM ECONOMIC-IMPLICATIONS OF CONTROLLING CRENATEBROOMRAPE (OROBANCHE-CRENATA FORSK.) IN BROAD BEAN (VICIA-FABA L.) UNDER VARIOUS MANAGEMENT STRATEGIES, Crop protection, 17(2), 1998, pp. 139-143
An economic model is described and used to investigate the short-and l
ong-term implications of controlling crenate broomrape (Orobanche cren
ata Forsk.) infestations in broad bean (Vicia faba L.) under different
management strategies. These include no use of herbicide, applying he
rbicide once after an infection severity (IS: number of emerged broomr
ape m(-2)) greater than or equal to 0.1, and applying herbicide every
year. Crenate broomrape population evolution was affected by initial I
S (ISo) at the time of implementing the strategy, regardless of the ma
nagement strategy adopted. Non-application of herbicide was satisfacto
ry when initial infection was very low (ISo less than or equal to 0.1)
resulting in average annualized benefits (AB) of about 600 and 505 US
$ ha(-1), after 3 and 9 years for early sowing dates, respectively. A
pplying herbicide once did not control parasite populations adequately
and could only represent an acceptable low-cost alternative in the lo
ng term when IS less than or equal to 1 giving an AB of about 653 and
630 US $ ha(-1) after 3 and 9 years for early sowing dates, respective
ly. Annual application of herbicide was the best strategy against broo
mrape at any ISo to minimize crenate broomrape populations and obtain
maximum net benefits per year regardless of broad bean cropping freque
ncy. A sensitivity analysis was performed to determine the effect of c
hanging the values of the main economic parameters (efficacy of the he
rbicide, expected yield, fixed and herbicide costs). In general, sensi
tivity coefficients were between 0.5 and 1, herbicide cost being the p
arameter which exerted the least effect on AB in all management strate
gies. Generally, an ISo less than or equal to 1 requires broomrape her
bicide treatments in all subsequent broad bean crops in order to ensur
e economic benefits. (C) 1998 Elsevier Science Ltd. All rights reserve
d.