Received: 30 July 2024 / Accepted: 05 February 2025 / Published Online: 06 March 2025
Abstract
The Shisham (Dalbergia sissoo) population is threatened by the fungal pathogens causing dieback disease. Research over the past decade has shown the involvement of multiple fungal pathogens in causing the dieback disease. Here we reported the RAPD-PCR-based genetic diversity in three potential fungal pathogens including Botrydiplodia theobromae, Fusarium solani, and F. oxysporum isolated from diseased plants across the Punjab province in Pakistan. Twenty fungal isolates of three major fungal species were isolated from dieback-infected trees from eight districts in Punjab Pakistan to investigate the genetic diversity with a set of fifteen RAPD markers of OPB, OPK, and OPL series. Consequently, fifteen markers produced 166 loci with an average of 55.33 loci per population. Of these, 76.31% loci were polymorphic highlighting the presence of abundant genetic diversity in pathogens. Moreover, OPK-06 primer showed a higher PIC value of 0.416 along with higher heterozygosity contents of 0.49. However, population structure analysis of each fungal strain grouped similar and dissimilar ones based on their amplification into the same and different clusters respectively. The isolates of B. theobromae of the Ayub Agriculture Research Institute (AARI) and Attock district showed higher genetic distance (0.6812) and were found in different clusters. Similarly, isolates of F. solani from UAF formed a different group which further highlighted its degree of polymorphism. Moreover, the UAF isolate displayed a maximum of 0.6432 genetic distance from the AARI isolate. Conversely, the isolates of F. oxysporum were grouped into two main groups highlighting the limited genetic diversity. Further, isolates from UAF also exhibited a maximum of 0.7372 genetic distance from AARI. Consistent results of UAF and AARI isolates of F. oxysporum and F. solani are suitable grounds for further genetic studies.
