Chitinous Materials from Blue Crab for Control of Root-Knot Nematode. I. Effect of Urea and Enzymatic Studies


  • R. Rodriguez-Kabana
  • D. Boube
  • R. W. Young


Biological Control, Callinectes sapidus, Chitin, Chitobiase, Clandosan, Cucurbita pepo, Lycopersicon esculentum, Meloidogyne arenaria, Organic Amendments, Phosphatase, Root-Knot Nematodes, Soil Enzymes, Urea, Urease


The efficacy of two chitinous materials (Clandosan(?) 601 and Clandosan(?) 719) derived from blue crab (Callinectes sapidus) wastes for control of Meloidogyne arenaria was studied in a greenhouse experiment. Both materials controlled the nematode on 'Summer Crookneck' squash (Cucurbita pepo) and on a subsequent planting of 'Rutgers' tomato (Lycopersicon esculentum) when preplant incorporated into soil at rates 10 g/kg of soil. The efficacy of mixtures of urea with Clandosan 601 was explored in a second greenhouse experiment with soil from the same origin. The number of galls/g of fresh squash root (first crop) or tomato (second crop) decreased sharply in response to increasing rates of urea (0-1.0 g/kg of soil) and Clandosan 601 (0-10 g/kg of soil). Treatments with urea alone at rates 0.5 g/kg of soil were phototoxic; however, combination treatments of urea + Clandosan 601 were not phytotoxic. Treatments with urea alone or with Clandosan 601 alone resulted in increased fresh shoot