Management of root-knot nematodes with resistant cotton cv. NemX

• Published in: Crop science 1999-03, Vol.39 (2), p.418-421
• Main Authors: Ogallo, J.L, Goodell, P.B, Eckert, J.W, Roberts, P.A
• Format: Article
• Language: English
• Subjects: Agricultural chemicals industry; Agriculture; Biological and medical sciences; biological resistance; Control; Cotton; crop rotation; crop yield; Cultivars; Cultural control; Fumigants; Fundamental and applied biological sciences. Psychology; Gossypium hirsutum; infestation; integrated pest management; Laws, regulations and rules; Medicago sativa; Meloidogyne incognita; Nematocides; Nematodes; Pest control; pest resistance; Phaseolus lunatus; Phytopathology. Animal pests. Plant and forest protection; population; population density; Protozoa. Invertebrates; Root-knot; Soils; suppression; Vigna unguiculata
• ISSN: 0011-183X; 1435-0653
• DOI: 10.2135/cropsci1999.0011183X0039000200020x

Root-knot nematode [Meloidogyne incognita (Kofoid and White) Chitwood] is a serious pest of cotton (Gossypium hirsutum L.) and many crops worldwide. Recent banning of most nematicides has increased the need for development of nematode resistant crop cultivars, such as NemX cotton, which was released in California in 1995. This study was conducted to determine the effectiveness of NemX in suppressing populations of M. incognita and protecting susceptible crops grown in rotation with it. NemX was grown in rotation with susceptible cotton cvs. Maxxa and Pima S7, susceptible lima bean (Phaseolus lunatus L. cv. Henderson), and resistant cowpea [Vigna unguiculata (L.) Walp. cv. CB 88] and alfalfa (Medicago sativa L. cv. WL525HQ). The experiments were done at Shafter, CA, during 1994-1996 on plots with sand loam soil and natural infestation of M. incognita race 3. NemX suppressed nematode populations strongly in all treatments and one planting was as effective as two successive ones. Lint yield of NemX averaged 1000 kg ha(-1), irrespective of preplant nematode density (Pi). In contrast, yields of susceptible Maxxa cotton varied indirectly with nematode Pi and ranged from 530 to 1360 kg ha(-1). NemX and resistant cowpea or alfalfa had about equal effectiveness in suppressing nematode population density in soil and in protecting a subsequent susceptible crop. Since different species of root-knot nematode attack many crops and M. incognita is the only species that reproduces well in cotton, utilization of NemX will greatly enhance the rotational value of cotton for managing the nematodes.