Submitted to: Biological and Cultural Tests for Control of Plant Diseases
Publication Type: Research Notes
Publication Acceptance Date: January 4, 2006
Publication Date: February 26, 2006
Citation: Thies, J.A., Fery, R.L. 2006. Reactions of regional cooperative southernpea (cowpea) breeding lines and checks to southern root-knot nematode race 3, 2003. Biological and Cultural Tests for Control of Plant Diseases. 21:V017. Technical Abstract: Southernpea breeding lines from the Regional Southernpea Cooperative Trial were evaluated for resistance to southern root-knot nematode, Meloidogyne incognita race 3, in a greenhouse test. The experimental design was a randomized complete block with four replicates. Each plot consisted of five seeds of an entry planted 10 cm apart and 2 cm deep in a greenhouse bench containing steam-pasteurized soil (2 parts sand : 1 part loamy sand). Nematode inoculum was cultured on Rutgers tomato (Lycopersicon esculentum) in the greenhouse. Eggs were extracted from tomato roots using 0.5% NaOCl. Seeds were planted on 8 Sept 2003 and the soil surrounding each seed was infested with ca. 3,000 M. incognita eggs suspended in 5 ml H2O. The greenhouse conditions were maintained for favorable growth of southernpea and nematode development. On 24 Oct 2003, the roots of the plants were lifted, washed, and evaluated for resistance to root-knot nematode using a 1 to 5 rating system, where 1 = 0 to 3% of root system galled or covered with egg masses, 2 = 4 to 25%, 3 = 26 to 50%, 4 = 51 to 79%, and 5 = >80% of root system galled or covered with egg masses. The standard resistant and susceptible check cultivars performed as expected. Six observational lines (US-1084, TX 160 BE, TX 162 PE, TX 158 BEgc, LA 94-1, and LA 95-17) and four advanced lines (US-1076, TX 123 BE, TX 116 BE, and TX 158 PEgc) were resistant (R), similar in reaction to the resistant check Mississippi Silver. Six observational lines (US-1080, US-1086, US-1088, AR96-854, AR01-874, AR01-1237, and LA 96-18) and eight advanced lines (US-1031, US-1071, AR96-868, AR01-1293, AR-1657, LA 94-55, LA 94-61, and LA 96-4) were susceptible (S), similar in reactions to the susceptible checks Coronet, Arkansas Blackeye #1, Pinkeye Purple Hull - BVR, and New Era.