Fusarium wilt or Panama disease poses a great risk to banana production worldwide and is caused by Fusarium oxysporum f. sp. Cubense (Foc). Its tropical race 4 (TR4) is a major problem for Cavendish banana growing areas. Basrai (Dwarf Cavendish) is the major cultivated variety in Pakistan and now recently been reported to be affected by Foc TR4 in certain areas in the Sindh province. To genetically characterize, three independent isolates (P.TH1, P.TH2 and P.Th3) were sampled from different fields in district Thatta and fungus was isolated on potato dextrose agar. The pure fungal isolates were used to establish Koch's postulates by testing their pathogenicity on tissue cultured Cavendish banana. A diagnostic PCR assay was optimized and used to sequence a reported molecular marker for specific detection of Foc TR4 and to sequence 28S-18S ribosomal RNA intergenic spacer region (IGS) from these local isolates. The phylogenetic of Pakistani isolates suggests that they belong to previously characterized lineage V of tropical race 4 of F. oxysporum cubense with 99% bootstrap support and show close relationship with Indonesian and Malaysian Foc TR4 isolates. The rapid spread of this disease in different banana growing areas of the Sindh is alarming and necessitates effective control of this through chemical and biocontrol, if remains unchecked, Foc TR4 can raise havoc to banana industry in Pakistan and would be devastating economically.
Adult plant resistance (APR) to wheat stem rust has been one of the approaches for resistance breeding since the evolution of the Ug99 race group and other races. This study was conducted to dissect and understand the genetic basis of APR to stem rust in spring wheat line ‘Copio’. A total of 176 recombinant inbred lines (RIL) from the cross of susceptible parent ‘Apav’ with Copio were phenotyped for stem rust resistance in six environments. Composite interval mapping (CIM) using 762 Genotyping-by-Sequencing (GBS) markers, identified 16 genomic regions conferring stem rust resistance. Assays with gene-linked molecular markers revealed that Copio carried known APR genes Sr2 and Lr46/Yr29/Sr58 in addition to the 2NS/2AS translocation that harbors race-specific genes Sr38, Lr37 and Yr17. Three QTL were mapped on chromosomes 2B, two QTL on chromosomes 3A, 3B, and 6A each, and one QTL on each of chromosomes 2A, 1B, 2D, 4B, 5D, 6D and 7A. The QTL QSr.umn.5D is potentially a new resistance gene and contributed to quantitative resistance in Copio. The RILs with allelic combinations of Sr2, Sr38, and Sr58 had 27-39% less stem rust coefficient of infection in all field environments compared to RILs with none of these genes and this gene combination was most effective in the US environments. We conclude that Copio carries several genes that provide both race-specific and non-race-specific resistance to diverse races of stem rust fungus and can be used by breeding programs in pyramiding other effective genes to develop durable resistance in wheat.
Ten geneta of plant nematode associated with coriander (Coriandrum sativum L.) were isolated and identified in ten different localities of Balochistan, Pakistan. The most common was Meloidogyne javanica followed by Basiria spp. Principal component analysis (PCA) and cluster analysis using Ward’s method were performed. The results of the two methods supported each other. Castor and mustard oilcakes and carbofuran, a chemical nematicide were used in treatments against Hoplolaimus Columbus and M. javanica larvae. Mustard oilcake was found to be more effective on H. Columbus while castor oilcake showed effective control on M. javanica. Bangladesh J. Sci. Ind. Res.56(1), 61-68, 2021
After decades of effective wheat stem rust control, due mainly to use of the Sr31 resistance gene in wheat, as of the early 2000s new virulent strains of the stem rust fungus, especially the Ug99 or the TTKSK races, are spreading and overcoming the resistance of commercial varieties worldwide, including the Sr24 and Sr36 resistance genes in Kenya. To address this, researchers are working to identify new resistance sources and to develop and release new high-yielding, resistant and adapted varieties. In this study we evaluated 707 advanced spring wheat lines and varieties for adult plant resistance (APR) to stem rust at the Njoro research station of the Kenya Agricultural & Livestock Research Organization, using a modified Cobb's scale, and for seedling resistance at the Cereal Disease Laboratory (CDL), University of Minnesota, using the 0-4 Stakman et al. (1962) scale. We found 101 lines that showed APR and, through molecular marker analysis, identified 18 lines carrying the stem rust resistance marker allele for the Sr25/Lr19 gene. Of these 18 lines, 11 were resistant to Ug99 at both the seedling and adult stages and 7 were susceptible at the seedling stage, showing infection type (IT) 3 to 4, and moderately susceptible at the adult plant stage. Another 20 lines were resistant at all stages of development, without Sr25/Lr19 marker allele indicated the possibility of carrying other genes for stem rust resistance. We shared the results with national program breeders and scientists in Pakistan to facilitate the use of resistant lines in crossing programs and enhance stem rust resistance in candidate wheat varieties. As a result number of lines resistant to Ug99/ and its variants (TTKSK, TTKST) have been identified and released as commercial varieties, including NR-397 (Pakistan-2013) and NR-356 (NARC-2011).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2025 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.