Genome Center

Popcorn adapted to Spanish conditions could be an interesting and profitable alternative to field corn. However, little is known about breeding popcorn germplasm for adaptation to Spain. Sesamia nonagrioides Lefèvbre is the main insect pest affecting popcorn quality and yield under Spanish growing conditions. The objectives of the study were the search for sources of resistance to S. nonagrioides among popcorn germplasm and to study the genetics of the resistance to S. nonagrioides attack. Eight breeding populations along with a five-inbred line diallel and two popcorn commercial checks were evaluated under S. nonagrioides infestation in 2 yr. Significant differences were found among general combining ability (GCA) effects for days to silking, S. nonagrioides tunnel length, general appearance of the ear, kernel moisture, and yield. Specific combining ability (SCA) effects were found to be significant for yield and ear damage. Therefore, heterotic patterns among popcorn materials should be taken into account to generate new popcorn hybrids that are not only more productive but also have higher kernel quality. Breeding popcorn populations BSP4APC0 and PSPW1C1 could be base germplasms in a breeding program for obtaining parental inbreds of healthy kernel popcorn hybrids. New inbred lines could be generated from the cross BP1 x BP2 that would have improved GCA and SCA effects for S. nonagrioides resistance when crossed to South American inbreds.

... G. Sandoya, A. Butrón, A. Ordás, and RA Malvar, Misión Biológica de Galicia, Spanish Council for Scientific Research (CSIC), Apartado 28, 36080 Pontevedra, Spain; A. Alvarez, Estación Experimental de Aula ... ing pest development, especially PSB, which has an Afri-can origin ...

Recurrent selection has been reported as successful for improving maize resistance against corn borers. This study was conducted to determine if phenolics concentration in maize changes during recurrent selection to improve stalk resistance to the Mediterranean corn borer. Three cycles of selection [EPS12(S)C0, ESP12(S)C2, and EPS12(S)C3] from the maize synthetic population EPS12 and test crosses to inbred lines A639, B93, and EP42 were field grown and artificially infested with Mediterranean corn borer larvae, and the pith tissues were sampled for biochemical analyses. Two major simple phenolic acids [p-coumaric (p-CA) and trans-ferulic (E-FA) acids] were identified in free and cell-wall fractions, whereas four isomers of diferulic acid (DFA) (8-5'l, 5-5', 8-o-4', and 8-5' benzofuran form) were present in the cell-wall bound fraction. The selection cycles EPS12(S)C0 and EPS12(S)C3 showed less damage and higher cell wall phenolics concentrations than the cycle EPS12(S)C2. In addition, higher concentrations of total DFAs were associated with shorter tunnel length and lower numbers of larvae per stem. The current study shows new and concrete evidence that the cell-wall bound phenolics could have a determinative role in the resistance to the Mediterranean corn borer, although future development of recurrent and divergent selection cycles will clarify this point.

... Eight maize landraces appropriate for manufacturing bread (Meiro, Bianco Perla, Sarraeus, Ribadumia, Rebordanes, S. Pedro do Sul, Gallego and Celanova), one breeding ... Kernel density was measured by the ethanol column test method developed by Paulsen and Hill (1985 ...

The pink stem borer (PSB)(Sesamia nonagrioides Lefèbvre, 1827; Lepidoptera: Noctuidae) is the main insect pest of maize (Zea mays L., Poaceae) in the Mediterranean area. Maize varieties partially resistant to PSB have been identified, but few studies have documented ...

Sesamia nonagrioides causes high yield losses in maize in northwestern Spain. Therefore, a recurrent selection programme to improve resistance against this pest has been carried out in a maize synthetic population. The main purposes of this investigation were to ...

... Genetics of resistance to the pink stem borer (Sesamia nonagrioides) in maize (Zea mays). ... Additional Information. How to Cite. Butrón, A., Sandoya, G., Revilla, P. and Malvar, R. (2009), Genetics of resistance to the pink stem borer (Sesamia nonagrioides) in maize (Zea mays). ...

A maize synthetic population was improved for resistance to the Mediterranean corn borer (MCB, Sesamia nonagrioides) while maintaining yield. The objectives of this research were to investigate whether yield and yield stability of the maize synthetic population named EPS12 were affected by selection for MCB resistance; also to determine which genotypic and environmental covariates could explain the genotype (G), environment (E) and genotype × environment (GE) effects for yield under corn borer infestation. Plants from three cycles of selection and their testcrosses to three inbred testers (A639, B93 and EP42) were evaluated at two locations in 2 years, under MCB and European corn borer infestations. After selection EPS12 was a more stable genotype. Hybrids derived from crosses between B93 and inbreds obtained from the initial cycles of selection could be recommended for cultivation in northern Spain. The yield of crosses between cycles of selection and testers increased when there were fewer days with temperatures >25°C and higher mean maximum temperatures. Differences in yield among these genotypes were mostly explained by resistance to corn borer attack. In general, among EPS12-derived materials, genetic characteristics that contribute to increased grain yield were also responsible for increased abiotic stress tolerance.