DMDP - A PLANT-DERIVED SUGAR ANALOG WITH SYSTEMIC ACTIVITY AGAINST PLANT-PARASITIC NEMATODES

The naturally occurring sugar analogue DMDP (2,5-Dihydroxymethyl-3, 4- dihydroxypyrrolidine) also known as (2R, 3R, 4R, 5R) -2,5-bis (hydroxy methyl)pyrrolidine-3, 4-diol), has been isolated from tropical legumes in the genera Lonchocarpus and Derris, and found to have a range of a ctivities against several plant parasitic nematode species. In vitro s tudies demonstrated that DMDP at 25 mug ml-1 inhibited cyst hatch of G lobodera pallida by 41%, and at 1000 muM ml-1 immobilised 53% of G. ro stochiensis juveniles after 72 h exposure. DMDP applied as a foliar sp ray showed systemic activity and decreased root galling of tomato by M eloidogyne spp. It was also effective when applied as a soil drench or seed dressing. The compound applied as a 30 mug ml-1 soil drench also inhibited virus acquisition and transmission, and root galling by Xip hinema diversicaudatum on Petunia. At 100 mug ml-1 DMDP enhanced the c ontrol of Globodera spp. on the partially resistant potato cv. Heather , reducing both the number of cysts/root and eggs/g soil. The potentia l of this systemic, phloem-mobile plant compound in the integrated con trol of nematodes is discussed.