Submitted to: Biological and Cultural Tests for Control of Plant Diseases
Publication Type: Research Notes
Publication Acceptance Date: 11/20/2002
Publication Date: 2/22/2003
Citation: THIES, J.A., FERY, R.L. REACTIONS OF REGIONAL COOPERATIVE SOUTHERNPEA (COWPEA) BREEDING LINES AND STANDARD CHECKS TO SOUTHERN ROOT-KNOT NEMATODE RACE 3, 2003. BIOLOGICAL AND CULTURAL TESTS FOR CONTROL OF PLANT DISEASES. 2003. Report No. 18:v017.DOI:10.1094/BC18.
Technical Abstract: 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 5 Aug and the soil surrounding each seed was infested with ca. 3,000 M. incognita eggs suspended in 5 ml H2O at planting. The greenhouse conditions were maintained for favorable growth of southernpea and nematode development. On 23 Sept, 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. Five observational lines (US-1076, TX 160 BE-gcgt, TX 158 PE-gc, TX 162 PE-gc and LA 94-1) and ten advanced lines (US-1033, US-1070, ARK 96-918, ARK 96-1022, TX 123 BE, TX 128 BE, TX 148 PE-gc, TX 139 CRM, TX 159 BE-gc, and TX 164 PE-gc) were resistant (R), similar in reaction to the resistant check Mississippi Silver. Eight observational lines (US-1067, US-1074, US-1071, ARK 98-348, ARK-95-356, LA 94-55, LA 96-4, and LA 96-18) and six advanced lines (US-1031, US-1069, LA 92-86, and LA 92-180, LA 95-62, and LA 96-21) were susceptible (S), similar in reactions to the susceptible checks Coronet, Arkansas Blackeye #1, Pinkeye Purple Hull, White Acre, and New Era.