Resistance to corn leaf aphid (Rhopalosiphum maidis Fitch) in tropical corn (Zea mays L.)

• Published in: Euphytica Vol. 172; no. 3; pp. 373 - 381
• Main Authors: So, Yoon-Sup, Ji, Hee Chung, Brewbaker, James L
• Format: Journal Article
• Language: English
• Published: Dordrecht Dordrecht : Springer Netherlands 01.04.2010; Springer Netherlands; Springer; Springer Nature B.V
• Subjects: Agronomy. Soil science and plant productions; Aphididae; Biological and medical sciences; Biomedical and Life Sciences; Biotechnology; Corn; epistasis; experimental design; Flowers & plants; Fundamental and applied biological sciences. Psychology; genetic resistance; Genetics and breeding of economic plants; Genotypes; Growing season; Hair; Hybrids; inbred lines; Leaves; Life Sciences; linkage (genetics); methodology; pest resistance; Plant Genetics and Genomics; Plant Pathology; Plant Physiology; Plant Sciences; population dynamics; recessive genes; Resistance to control; Rhopalosiphum maidis; selection criteria; Varietal selection. Specialized plant breeding, plant breeding aims; Vegetables; Zea mays; Hawaii; Corn leaf aphid; Additive-dominance model; Generation mean analysis; Supersweet corn; Aphidoidea; Monocotyledones; Zea mays; Insecta; Tropical zone; Dominance; Modeling; Cereal crop; Quantitative genetics; Resistance; Rhopalosiphum maidis; Pest; Homoptera; Gramineae; Arthropoda; Angiospermae; Genetic improvement; Aphididae; Spermatophyta; Invertebrata
• ISSN: 0014-2336; 1573-5060
• DOI: 10.1007/s10681-009-0044-z

Corn leaf aphids (Rhopalosiphum maidis Fitch) are found throughout the year on maize in Hawaii and occasionally cause yield loss. Sweet corn inbred Hi38-71 was observed to have high field resistance to aphids and was chosen for this genetic study. An artificial infestation technique was developed using hair-pin clip cages (2.2 cm diameter) which we devised and built. The cages were applied to field-grown plants into which three wingless viviparous adults were placed. Aphid populations were classified on a 1-10 rating scale after about 2 weeks based on digital images of the cages. Mean aphid coverage ratings were 2.97 for the resistant parent and 7.28 for the susceptible parent (representing >200 insects per cage). The F₁ hybrids showed similar susceptibility (6.72), showing resistance to be recessive in nature. Six generations of the cross between Hi38-71 and susceptible inbred Hi27 were artificially infested to provide a generation mean analysis of 360 treated plants over two growing seasons. A joint scaling test showed that the fit to a 3-parameter additive-dominance model satisfactorily explained the observed variability with no assumed linkage or epistasis. We conclude that resistance to corn leaf aphid in Hi38-71 is conferred by a single recessive gene labeled aph. These results concur with a previous study under uncontrolled natural infestation in a single environment. The hair-pin clip cage method was most effective in distinguishing resistant and susceptible genotypes under diverse natural growing conditions in Hawaii.