Diallel analyses reveal the genetic control of resistance to ascochyta blight in diverse chickpea and wild Cicer species
- 151 Downloads
Ascochyta blight is a major fungal disease affecting chickpea production worldwide. The genetics of ascochyta blight resistance was studied in five 5 × 5 half-diallel cross sets involving seven genotypes of chickpea (ICC 3996, Almaz, Lasseter, Kaniva, 24B-Isoline, IG 9337 and Kimberley Large), three accessions of Cicer reticulatum (ILWC 118, ILWC 139 and ILWC 184) and one accession of C. echinospermum (ILWC 181) under field conditions. Both F1 and F2 generations were used in the diallel analysis. The disease was rated in the field using a 1–9 scale. Almaz, ICC 3996 and ILWC 118 were the most resistant (rated 3–4) and all other genotypes were susceptible (rated 6–9) to ascochyta blight. Estimates of genetic parameters, following Hayman’s method, showed significant additive and dominant gene actions. The analysis also revealed the involvement of both major and minor genes. Susceptibility was dominant over resistance to ascochyta blight. The recessive alleles were concentrated in the two resistant chickpea parents ICC 3996 and Almaz, and one C. reticulatum genotype ILWC 118. The wild Cicer accessions may have different major or minor resistant genes compared to the cultivated chickpea. High narrow-sense heritability (ranging from 82% to 86% for F1 generations, and 43% to 63% for F2 generations) indicates that additive gene effects were more important than non-additive gene effects in the inheritance of the trait and greater genetic gain can be achieved in the breeding of resistant chickpea cultivars by using carefully selected parental genotypes.
KeywordsAscochyta rabiei Diallel analysis Field screening Genetic component Hayman procedure Inheritance
We thank Dr Tanveer Khan, Mr Alan Harris and Mr Stuart Morgan for their expertise and assistance in field screening for disease. We thank Dr Fucheng Shan for providing wild Cicer germplasm and Miss Leila Eshraghi for technical support. We are grateful to Dr Pooran Guar for critical comments on the manuscript. This project was partially funded by Ministry of Science, Research and Technology of Iran and CLIMA.
- FAO (2005) FAOSTAT DATABASE, FAO, Rome. http://faostat.fao.org/faostat/. Cited 20 March 2006Google Scholar
- Jinks JL (1956) The F2 and backcross generations from a set of diallel crosses. Heredity 10:1–30Google Scholar
- Kusmenoglu I (1990) Ascochyta blight of chickpea: inheritance and relationship to seed size, morphological traits and isozyme variation. MSc thesis, Washington State UniversityGoogle Scholar
- Mather K, Jinks JL (1982) Biometrical genetics. Methuen and Co Ltd, LondonGoogle Scholar
- Nene YL, Sheila VK (1992) Important disease problems of kabuli chickpea. In Singh KB, Saxena MC (eds) Disease resistance breeding in chickpea. ICARDA Aleppo, Syria, pp. 11–22Google Scholar
- Reddy MV, Singh KB (1984) Evaluation of a world collection of chickpea germ plasm accessions for resistance to ascochyta blight. Plant Dis 68:900–901Google Scholar
- Siddique KHM, Regan KL, Baker MJ (2004) New ascochyta blight resistant, high quality kabuli chickpea varieties for Australia. In: New directions for a diverse planet: Proceedings of the 4th International Crop Science Congress. Brisbane, Australia, 26 Sep–1 Oct 2004Google Scholar