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Phytophthora root rot and wilt (PRRW), caused by Phytophthora rubi and potentially other species of Phytophthora , is a destructive disease of raspberry in Canada and worldwide. In this study, trials were conducted over multiple years (2019–2022) in two fields, with pathogen (P. rubi) inoculated (PI) and naturally infested (NI) fields, to evaluate foliar and soil applied fungicides with different modes of action and application timings to manage PRRW. In addition, PRRW progress was also monitored in one PI field and four NI fields. In PI field plots, PPRW foliage and wilting symptoms appeared 6–8 weeks later and disease index was significantly (p < 0.0042) lower in the cultivar 'Cascade Bounty' than the cultivars 'Meeker' and 'Tulameen', indicating that 'Cascade Bounty' showed field tolerance to the disease. The efficacy of foliar fungicides (fosetyl-Al and phosphites) and soil-applied fungicides (oxathiapiprolin, metalaxyl-m, and cyazofamid) were assessed on susceptible cultivars at both sites. In PI plots, the fungicide treatments significantly enhanced (p = 0.01 to < 0.0001) numbers of primocanes and floricanes, as well as weight, percent witling index, and fruit yield of floricanes. Soil application of a tank mix or rotation of oxathiapiprolin and metalaxyl-m, and alternating these products with cyazofamid, was more effective compared to other fungicides in reducing PRRW and improving plant vigor. Our study identified effective fungicide treatment options for PRRW, allowing growers to alternate new chemistries with currently registered fungicides to reduce the risk of fungicide resistance development. • Phytophthora root rot and wilt (PRRW) symptoms were more severe on raspberry cultivars 'Meeker' and 'Tulameen' than in 'Cascade Bounty'. • Tank mix of oxathiapiprolin and metalaxyl-m alone or in combination with cyazofamid significantly reduced PRRW and increased plant vigor. • Fungicide treatments increased numbers of primocanes, floricanes (FC), weight of FC, and fruit yield. • Host resistance and fungicide applications can be integrated for PRRW management. [ABSTRACT FROM AUTHOR]

Dry root rot (DRR) is an important emerging disease of mungbean caused by fungus Macrophomina phaseolina. The disease is seed and soil-borne and hence management is difficult. Exploitation of host resistance could be a good option to manage the disease. The objectives of this study were to characterize the isolates of M. phaseolina from three legume crops and to identify resistant sources against DRR of mungbean. Isolates of M. phaseolina from mungbean, urdbean, and vegetable soybean were identified using morphological characteristics and sequencing internal transcribed sequence (ITS) region of 18S rRNA. Isolates of M. phaseolina from urdbean and vegetable soybean were inoculated on susceptible check genotype of mungbean to assess their pathogenicity. Forty three mungbean genotypes were screened against M. phaseolina isolate of mungbean using the paper towel method to identify sources of resistance. Among these genotypes, 9 were resistant in repeated experiment, with disease score ranging from 1.9 to 3.0. Resistant genotypes showing lower disease score, namely IPM99-125, EC693368, and EC693369, were further screened using the sick pot method to confirm their resistance. Among these three genotypes, IPM99-125 showed consistently higher plant survival rate followed by EC693368 and EC693369 as compared to susceptible checks (VC3960-88, KPS1). In addition, these three genotypes were resistant when screened with two strains of M. phaseolina isolated from urdbean and vegetable soybean, with IPM99-125 having lower disease score. The mungbean genotype IPM99-125 could be useful in mungbean breeding programs to develop root rot-resistant varieties. • Macrophomina phaseolina isolated from mungbean, urdbean and vegetable soybean showed identical cultural and molecular characteristics. • Screening of 43 mungbean genotypes against DRR revealed resistance of IPM99-125, EC693368 and EC693369 genotypes. • The above three genotypes also showed resistance against M. phaseolina isolated from urdbean and vegetable soybean. • Genotype IPM99-125 exhibited higher plant survival could be useful in mungbean breeding programs to develop DRR resistant varieties. [ABSTRACT FROM AUTHOR]