effect of macroelements (npk) in the control of tetranychus urticae koch (acari: prostigmata: tetranychidae) on derakhshan bean cultivar and its agronomic characteristics

abstract common bean (phaseolus vulgaris l.) is one of the most important crops in lorestan province with about 23000 ha. in this area, two spotted spider mite (tssm) tetranychus urticae koch is the key pest of this crop. to study the effect of macroelements (npk) fertilizers, on controlling tssm and their effect on some agronomic characters of derakhshan bean cultivar, two same trails (1. treatmented with acaricide 2. no treatmented) were conducted in two fields at borujerd agricultural research station in 2002. the experiment was carried out according to randomized complete block design in factorial arrangement with 18 treatments and 4 replications. treatments were based on three factors: nitrogen (n0=0, n1=50 and n2=65 kg/ha), phosphore (p0=0, p1=100 and p2=130 kg/ha) and potassium (k0=0 and k1=50 kg/ha). results showed that in the second trial (no treatmented trial), the seed yield was significantly decreased by increasing the nitrogen fertilizer levels. in most sampling times, number of tssm/leaf in treatment n0p2k1, was significantly lower than that of most treatments. also, the potassium fertilizer in treatment n1p0k1 caused an increasing in number of pods/plant. based on this research treatment n0p2k1 was recommended in integrated control of tssm in common bean fields.