The new trends in the consumption of table grapes and the growing interest in the environmental impact of this crop have pushed breeders toward the development of seedless cultivars endowed with resistance, through crossbreeding programs. To obtain seedless grapes, the use of embryo-rescue techniques is fundamental. In this research, a grape embryo-culture protocol was optimized and validated by using 39 cultivars and 41 cross-combinations carried out in the framework of a large private table grape program of the private network Italian Variety Club in the period 2017–2021 evaluating several factors, such as the improvement in embryo formation, germination and growth, and plantlet development. The embryo culture attitude of crosses between different combinations of seedless parents was assessed, and the rates of embryo development from the extracted ovules mostly ranged from 3.5 to 35.5% with 5 out of 43 genotypes outliers. Experiments conducted at different sampling times, in a range of 43–62 days after pollination (DAP), did not show significant differences between the samples analyzed, while the rate of embryos developed with the applied protocol proved its employability on multiple genotypes, although the grapevine genotype significantly influenced the technique efficiency.

Apiospora marii (syn. Arthrinium marii) is an ascomycete recently associated with olive tree dieback in Italy and Spain. In this study, a quantitative PCR (qPCR) and a digital droplet PCR (ddPCR) were developed for its detection. Considering the sequences available in GenBank, the ITS region was selected, and two primer/probe sets (AM135 and AM158) were generated. The optimization of the PCR conditions showed that 60°C was the best annealing temperature and 500/250 nM was the best primer/probe concentration in both assays. Under these conditions, 1 fg μl ⁻¹ of A. marii DiSSPA_A1 DNA was detectable by qPCR, corresponding to a Cq value of 32 for AM135 and 33 for AM158. The same concentration was the lowest detected in ddPCR, corresponding to 0.20 and 0.12 c μl ⁻¹ , respectively, for AM135 and AM158. The specificity of both primer/probe sets was tested in qPCR and ddPCR using the DNA of microorganisms commonly associated with olive wood and different olive cultivars. Untargeted amplifications were observed using the DNA of some isolates, and consequently the PCR reaction was stopped at the 37th cycle. The primer/probe set AM158 showed the best performance, and it was used for the validation in qPCR and ddPCR using the DNA extracted from healthy, artificially inoculated, and naturally infected olive trees in the field. Both positive amplification and A. marii colonies were always obtained from samples artificially inoculated and from naturally infected olive trees in the field. The diagnostic tools can be used for monitoring A. marii and will be particularly helpful for evaluations on plant propagation material and to investigate aspects of the fungus’s lifestyle.

Polystigma amygdalinum the causal agent of Red Leaf Blotch (RLB), is responsible for one of the most important foliar diseases affecting almond [Prunus dulcis (Miller) D.A. Webb] in the Mediterranean Basin and the Middle East. The study is aimed at improving knowledge on RLB epidemiology and the role of environmental conditions in disease development. Field monitoring was conducted from 2022 to 2025 in three almond orchards located in Apulia (southern Italy) and characterized by different microclimatic conditions. A total of 39 cultivars, including Apulian local germplasm and international cultivars (‘Belona’, ‘Genco’, ‘Guara’, ‘Ferragnès’, ‘Filippo Ceo’, ‘Lauranne^® Avijor’, ‘Soleta’, and ‘Supernova’), were evaluated. Symptoms occurred from late spring to summer, resulting particularly severe on ‘Guara’ and ‘Lauranne^® Avijor’, whereas ‘Belona’, ‘Ferragnès’, ‘Genco’, and ‘Supernova’ exhibited the highest tolerance. To our knowledge, this is also the first report of RLB tolerance by ‘Filippo Ceo’, ‘Ficarazza’, ‘Centopezze’, and ‘Rachele piccola’ representing potential genetic resources for breeding programs. Moreover, these findings reinforced previous observations proving that RLB was less severe on medium-late and late cultivars. Disease incidence varied significantly among sites and years and was strongly associated with increased rainfall, higher relative humidity, and mild temperatures recorded in November, influencing disease occurrence in the following growing season. P. amygdalinum was consistently detected by qPCR in all RLB-affected tissues and, in some cases, from mixed early RLB + Pseudomonas-like symptoms. From some leaves with early RLB symptoms, P. amygdalinum was also successfully isolated in pure culture. Overall, our results provide clear evidence that P. amygdalinum is the sole fungal pathogen consistently associated with typical RLB symptoms in Apulia (southern Italy) and highlight important cultivar-dependent differences. Its frequent molecular detection in leaves showing atypical or mixed symptoms suggests unresolved epidemiological aspects requiring further investigation.