Effects of Nematicide Seed Treatments with and without Foliar Applications of Vydate-CLV on the Growth and Development of G. hirsutum Grown in R. Reniformis Infested Soils

Reniform nematode (Rotylenchulus reniformis Linford and Oliveira)  infests 36% of  Mississippi cotton acres and promotes great economic losses.  For years nematodes have been controlled using Temik 15G or soil fumigants.  With Temik 15G loss and  soil fumigant expense there is need to improve NST performance via applications of Vydate-CLV® because of systemic and nematicidal properties.    In greenhouse studies all NSTs provided greater biomass.  Aeries + Votivo produced greater biomass at Pi  5,000 reniform nematodes/500 cc of soil.  Aeries alone produced reduced biomass at lower initial populations of 2,500 reniform nematodes/500 cc.  Temik 15G showed excellent shoot biomass until  Pi  7,500 reniform nematodes/500 cc of soil but root weights of Temik 15G at all nematode levels were not better significantly than UTC at 0 and 2,500 reniform nematodes indicating root growth restriction.   In-season plant mapping indicated reduced NFFB with all nematicide treatments. Plant height and height to node ratios were increased with Vydate-CLV  as verified by accumulated internode measurements.  During square growth period  no differences occurred in retention at fruiting position one but Vydate-CLV treatments did yield higher retention at positions > two.  Final  evaluation indicated no retention difference at position one but Vydate-CLV treatments did increase retention at position two.  Plant zone observation show little difference in zone one (N 5-9) and Zone two (N 10-14) during square.  However, bloom retention improved when NSTs were combined with Vydate-CLV across all zones for position one and two.  Vydate-CLV treatment further increased retention at Zones one, two and three (N 15-19) during the open boll phase at fruiting position one and two.  All NSTs were improved using Vydate-CLV equaling that of Temik 15G which provided greatest retention. This was further observed where Vydate-CLV treatments increased yields above NST treatments.