Control of Rotylenchulus reniformis on Pineapple with Emulsifiable 1,3-Dichloropropene. B. S. Sipes, Assistant Professor, Department of Plant Pathology, University of Hawaii at Manoa, Honolulu 96822. D. P. Schmitt, Professor, Department of Plant Pathology, University of Hawaii at Manoa, Honolulu 96822. Plant Dis. 80:571. Accepted for publication 2 February 1996. Copyright 1996 The American Phytopathological Society. DOI: 10.1094/PD-80-0571.

An emulsifiable formulation of 1,3-dichloropropene (1,3-D SL) was tested for efficacy against Rotylenchulus reniformis, the reniform nematode, in pots and in the field. Nematode population densities were reduced by 50% at 25 mg a.i. per g of soil in pot trials. In the field, efficacy (posttreatment numbers divided by Pretreatment numbers) was similar between 1,3-D SL and 1,3-D VL (volatile liquid) at 407 kg a.i./ha. At 204kg a.i./ha, 1,3-D SL was less effective than 1,3-D SL or VL at 407 kg a.i./ha in controlling the nematode but gave better control than no treatment (P < 0.05). Postplant application of 113 kg a.i. 1,3-D SL per ha did nol provide sufficient nematode control to prevent yield reduction compared with a postplant fenamiphos (1.7 kg a.i./ha) treatment. Preplant fumigation with 1,3-D reduced the numbers of reniform nematode, but the population resurged within 10 months. Thereafter, regardless of nematicide, soil population densities of R. reniformis did not differ among treatments.