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Abstract Background Common bean (Phaseolus vulgaris) is considered a staple food in a number of developing countries. Several diseases attack the crop leading to substantial economic losses around the globe. However, the crop has rarely been investigated for multiple disease resistance traits using Meta-analysis approach. Results and conclusions In this study, in order to identify the most reliable and stable quantitative trait loci (QTL) conveying disease resistance in common bean, we carried out a meta-QTL (MQTL) analysis using 152 QTLs belonging to 44 populations reported in 33 publications within the past 20 years. These QTLs were decreased into nine MQTLs and the average of confidence interval (CI) was reduced by 2.64 folds with an average of 5.12 cM in MQTLs. Uneven distribution of MQTLs across common bean genome was noted where sub-telomeric regions carry most of the corresponding genes and MQTLs. One MQTL was identified to be specifically associated with resistance to halo blight disease caused by the bacterial pathogen Pseudomonas savastanoi pv. phaseolicola, while three and one MQTLs were specifically associated with resistance to white mold and anthracnose caused by the fungal pathogens Sclerotinia sclerotiorum and Colletotrichum lindemuthianum, respectively. Furthermore, two MQTLs were detected governing resistance to halo blight and anthracnose, while two MQTLs were detected for resistance against anthracnose and white mold, suggesting putative genes governing resistance against these diseases at a shared locus. Comparative genomics and synteny analyses provide a valuable strategy to identify a number of well‑known functionally described genes as well as numerous putative novels candidate genes in common bean, Arabidopsis and soybean genomes.

Background: Common bean (Phaseolus vulgaris) is considered a staple food in a number of developing countries. Several diseases attack the crop leading to substantial economic losses around the globe. However, the crop has rarely been investigated for multiple disease resistance traits using Meta-analysis approach. Results and conclusions: In this study, in order to identify the most reliable and stable quantitative trait loci (QTL) conveying disease resistance in common bean, we carried out a meta-QTL (MQTL) analysis using 152 QTLs belonging to 44 populations reported in 33 publications within the past 20 years. These QTLs were decreased into nine MQTLs and the average of confidence interval (CI) was reduced by 2.64 folds with an average of 5.12 cM in MQTLs. Uneven distribution of MQTLs across common bean genome was noted where sub-telomeric regions carry most of the corresponding genes and MQTLs. One MQTL was identified to be specifically associated with resistance to halo blight disease caused by the bacterial pathogen Pseudomonas savastanoi pv. phaseolicola, while three and one MQTLs were specifically associated with resistance to white mold and anthracnose caused by the fungal pathogens Sclerotinia sclerotiorum and Colletotrichum lindemuthianum, respectively. Furthermore, two MQTLs were detected governing resistance to halo blight and anthracnose, while two MQTLs were detected for resistance against anthracnose and white mold, suggesting putative genes governing resistance against these diseases at a shared locus. Comparative genomics and synteny analyses provide a valuable strategy to identify a number of well‑known functionally described genes as well as numerous putative novels candidate genes in common bean, Arabidopsis and soybean genomes. [ABSTRACT FROM AUTHOR]

The fungal genus Colletotrichum includes numerous important plant pathogenic species, some of which causes fruit bitter rot as well as leaf lesions (leaf black spot) on major crops, leading to yield losses (Fu et al. 2019; Talhinhas & Baroncelli, 2023). C. acutatum was reported associated with black spot on fallen, immature fruit of pear ( Pyrus pyrifolia ) in New Zealand (Damm et al. 2012); however, to our knowledge, this species has not been reported in Italy or nowhere else. In 2022, a significant increase of anthracnose symptoms was observed on pears in Emilia-Romagna region, Italy. Symptoms, such as round brown lesions of 1 to 4 cm, appeared on more than 50% of refrigerated stored fruit. These symptoms were undetectable at the end of September 2022 and appeared after a five-month period of storage (February 2023) at 4°C (e-Xtra 1A and B). Fungal isolates were obtained from symptomatic pears after surfaces sterilization with 96% ethanol by culturing necrotic tissue pieces on Potato Dextrose Agar at 25°C in the dark (e-Xtra 1C and D). Cultures were shades of coral color, from opalescent to sunkist coral, with slight aerial mycelium becoming grey and darker with age. When observed from the reverse side, the color was pink and, with age, became coral orange to dark amaranth. Conidia observed with a light microscope appeared hyaline and fusiform, 8 to 16 × 2.5 to 4 μm, with two pointed ends or one rounded end. (e-Xtra 1E) One reference isolate, named L51, was used for molecular characterization. Total genomic DNA was extracted, and the ITS region of rDNA amplified using the universal primers ITS1 and ITS4, then sequenced. The resulting sequences were 100% identical to those of C. acutatum (NR_144794.1: strain CBS 112996 ITS region; from TYPE material). Based on Damm et al. (2012), partial ACT, GAPDH, CHS and TUB2 gene sequences were also amplified and sequenced (GenBank Accession numbers: ITS: OR882016, ACT: OR882013, GAPDH: OR882011, CHS: OR882012, TUB2: OR882010), to characterize the isolates. Additionally, the multilocus phylogenetic analysis carried out with the obtained and reference sequences (Damm et al. 2012) revealed the species of analyzed isolates and confirmed the BLAST results, identifying the strain as C. acutatum (e-Xtra 1F). Koch's postulates were performed on 10 'Kaiser' pears. Surfaces sterilized fruits with 96% ethanol were subjected to wound inoculation with a conidial suspension (106 conidia ml-1) while 10 fruit were used as negative control and inoculated with sterile water. Following an incubation period of 8-14 days at 15-20°C, symptoms around the inoculation site resembled those initially observed, while the negative control showed no symptoms. Fungal colonies re-isolated from the lesions exhibited the same morphological characteristics as the original isolates. To our knowledge, this is the first report of pear bitter rot caused by C. acutatum in Italy and in Europe (Talhinhas & Baroncelli, 2023). Yet, bitter rot had not been recognized as a notable issue in pear cultivation. Nevertheless, given that pears rank as the 8th most cultivated fruit globally and economically very significant for the Emilia Romagna region in Italy the emergence of pear bitter rot caused by Colletotrichum species has the potential to evolve into a significant worldwide problem, warranting further investigation.

The purpose of this research is evaluating the results of the effect of M. bracteata, Desmodium sp y P. phaseoloides cover crops in growth, and their influence in the phytosanitary conditions of a two years old natural rubber crop in the "Altillanura Colombiana". We established treatments by cover crop with three repeats and a control crop. The development of the trees was evaluated through the measurement of perimeter and total height. Additionally, inoculations of C. gloesporioides were carried out in the three cover crops under semi-controlled conditions. It was found that the three cover crops generated a slight increase in the organic matter of the soil and have a favorable effect on the development of the trees. Also, that the most frequently isolated fungi corresponded to Cladosporium sp., E. sorgui and Fusarium sp., and that the inoculations showed that the three coverages are susceptible to C. gloesporioides. [ABSTRACT FROM AUTHOR]

Anthracnose caused by several species of Colletotrichum is one of limiting factors for chilli production. Up to now the control of antrachnose disease still rely on regular and intensive application of synthetic fungicides. Application of similar active ingredients of synthetic fungicides may create resistance of the pathogens. This study was conducted to evaluate the sensitivity of three species of Colletotrichum against four commercial fungicides with different active ingredients, i.e. benomyl, chlorotalonil, mancozeb, and propineb. The sensitivity level and the potential occurrence of resistance of Colletotrichum were observed based on relative inhibition rate using poisoning food method. The results showed that all isolates were highly resistant to chlorotalonil, even up to ten times of the highest recommended concentrations. The tested fungal isolates were resistant or highly resistant to the recommended concentrations of mancozeb and propineb, but they were still sensitive when the concentrations were increased up to five times. Isolates of Colletotrichum spp. showed sensitive to highly sensitive response to benomyl.

Yam tuber production has been affected for anthracnose, decreasing farmers´ incomes. Genetic resistance has been attempted; however, the species narrow genetic base favors fungal re-infection. Selection of new cultivars is hampered by low flowering and seed setting. The ability of embryogenic cultures to generate in vitro resistance to Colletotrichum gloeosporioides by co-culturing proembryogenic masses (PEMs) with several concentrations of the fungal filtrate was evaluated. PEMs were induced from “Pico de botella” var. foliar explants on MS supplied with 2,4-D. Proliferated PEMs were challengedwith several concentrations of the culture filtrate and dually cultured with fungal mycelia. PEMs showed susceptibility to fungal filtrate and mycelia. No embryos were recovered from challenged or filtrate-free PEMs.

Yam tuber production has been affected for anthracnose, decreasing farmers' incomes. Genetic resistance has been attempted; however, the species narrow genetic base favors fungal re-infection. Selection of new cultivars is hampered by low flowering and seed setting. The ability of embryogenic cultures to generate in vitro resistance to Colletotrichum gloeosporioides by co-culturing proembryogenic masses (PEMs) with several concentrations of the fungal filtrate was evaluated. PEMs were induced from "Pico de botella" var. foliar explants on MS supplied with 2,4-D. Proliferated PEMs were challenged with several concentrations of the culture filtrate and dually cultured with fungal mycelia. PEMs showed susceptibility to fungal filtrate and mycelia. No embryos were recovered from challenged or filtrate-free PEMs. [ABSTRACT FROM AUTHOR]