Pathogenicity and rDNA-ITS sequence analysis of the Corynespora cassiicola isolates from rubber plantations in Indonesia

Abstract

Corynespora cassiicola is an important pathogen causing Corynespora leaf fall disease on the rubber tree. Analysis of virulence, rDNA-ITS sequence and identification of cas gene were undertaken to investigate the effect of agro-climatic conditions and host rubber clones to virulence of 23 C. cassiicola isolates on six clones (RRIC 100, BPM 24, BPM 1, PB 260, GT 1 and RRIM 600) and to observed the evolution pattern of C. cassiicola isolates. Virulence analysis showed that there is an interaction between isolates and clones, indicating the differences of each isolates virulence to six clones. Agro-climatic conditions and host clones influenced the virulence of isolates and rDNA-ITS sequence variation. Analysis of rDNA-ITS showed that there were three of Single Nucleotide Polymorphism (SNP) that separated of isolates into 5 haplotypes. Most of the isolates belonging to the haplotype 1. Phylogenetic analysis indicated that C. cassiicola have a high diversity, however the clustering did not indicate country and host species of isolates. This information will be very useful on developing strategies of disease management and rubber plant breeding towards resistance to CLF disease.

The fungal pathogen Corynespora cassiicola: A review and insights for target spot management on cotton and Soya bean

“…The wide host range of C. cassiicola and its cultivar preference were explained based on the pathogen diversity (Déon et al, 2014). Different genes of C. cassiicola have been amplified to construct phylogenetic trees to understand the evolution and variability of C. cassiicola isolates and to help build disease management strategies (Banguela-Castillo et al, 2020;Bentes et al, 2018;Déon et al, 2014;Dixon et al, 2009;Hieu et al, 2020;Nghia et al, 2008;Oktavia et al, 2017;Qi et al, ,2009Qi et al, , , 2011Shimomoto et al, 2011;Shrestha et al, 2017;Silva et al, 2003;Wu et al, 2019). Dixon et al, (2009) conducted the most prominent study on (Qi et al, 2009).…”

“…Analysis of rDNA ITS sequences among 23 C. cassiicola isolates from Indonesia showed high genetic diversity, but clusters did not correlate with host species or geographical origin. Five haplotypes were found based on three SNP’s (Oktavia et al., 2017). No genetic diversity was found for C. cassiicola isolates from cotton in the United States, whereas higher diversity was found for isolates from Soya bean.…”

ANALISIS KERAGAMAN KETAHANAN GENETIK PROGENI F1 HASIL PERSILANGAN BPM 1 X RRIM 600 TERHADAP ISOLAT Corynespora cassiicola

“…Dengan ditemukannya perubahan ketahanan klonklon yang sebelumnya tahan menjadi r e n t a n , m a k a d i k h a w a t i r k a n a k a n munculnya ras baru pada isolat tersebut di Malaysia (Nghia et al, 2010;Atan et al, 2011). Berdasarkan analisis jejaring (network analysis) menggunakan metode Reduced Median gen ITS-rDNA isolat C. cassiicola asal berbagai klon karet di Indonesia terlihat bahwa terdapat lima haplotipe isolat C. cassiicola asal tanaman Oktavia karet Indonesia, dimana frekuensi isolat terbanyak ditemukan pada haplotipe 1 dan isolat-isolat tersebut secara umum menyerang klon-klon baru seri IRR (Indonesian Rubber Research) (Oktavia et al, 2017). Haplotipe tersebut menunjukkan kelompok ras isolat (Nghia et al, 2010), sehingga setidaknya terdapat lima kelompok ras isolat C. cassiicola yang ada di Indonesia.…”

“…Isolasi-isolat dilakukan dari daun terinfeksi yang menunjukkan gejala serangan PGDC. Hasil analisis virulensi pada enam klon karet dengan berbagai tingkat ketahanan menunjukkan bahwa keempat isolat tersebut merupakan isolat yang tergolong memiliki virulensi tinggi dan tergolong kepada haplotipe 1 (CC-GT 1 dan CC-IRR 104) dan haplotipe 2 (CC-RRIM 600 dan CC-IRR 112) (Oktavia et al, 2017).…”

“…Tingkat virulensi tertinggi ditemukan pada isolat yang diisolasi dari klon GT 1 dan terendah pada isolat yang diisolasi dari klon RRIM 600. Hasil yang sama juga ditemukan pada plasma nutfah karet IRRDB 1981, dimana tanaman lebih sensitif terhadap aktivitas filtrat toksin isolat asal klon GT 1 dari pada isolat asal klon RRIM 600 (Oktavia et al, 2016) meskipun berdasarkan analisis tingkat virulensi isolat terhadap enam klon karet diketahui bahwa isolat asal klon RRIM 600 lebih virulen dibandingkan isolat asal GT 1 (Oktavia et al, 2017). Hal ini lumrah ditemukan dalam interaksi patogen dengan tanaman karena adanya kesesuaian ekspresi gen-gen virulen pada patogen dengan gen-gen resistensi pada inang.…”