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Cercospora leaf spot induced by the fungus Cercospora beticola Sacc is the most important leaf disease of sugar beet (Beta vulgaris L.) in the world. Managing this enemy requires an integrated approach combining farming practices, resistant varieties, and chemical treatments. Indeed, chemical treatments against fungi provide control of the disease but generate another problem; the resistance to fungicidal molecules. Studies have detected the mutation points responsible for the resistance traits of this pathogen against the main fungicide groups (MBC, DMI, QoI). From the perspective of managing the resistance, alternative control methods such as the use of antagonists (fungi and bacteria). [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the antifungal activity of the aqueous extracts of two wild Lamiaceae species against P. expansum and B. cinerea and the impact of these treatments on fruit quality parameters. The in vitro results showed significant effect of the two aqueous extracts on both fungi mycelial growth. A. alpinus exhibited high antifungal efficacy against P. expansum with an inhibition rate ranging from 34.32 to 90.76% whereas T. vulgaris exhibit an inhibition rate against B. cinerea ranging from 61.87 to 97.94%. These results indicated that A. alpinus and T. vulgaris were extremely potent against both pathogens with an EC50 ranging from 0.82 to 2.39%. The in vivo experiments on apple fruit were very promising with an approximate efficacy varying from 64 to 79% with no impacts on fruit quality parameters. These results provide evidence that both plant species are an effective alternative to control postharvest diseases of fruit. [ABSTRACT FROM AUTHOR]

Citrus dry root rot caused by members of Fusarium species is among the most devastating diseases that delimits citrus production worldwide. The present study aimed at evaluating the efficacy of fungicides against Fusarium solani (as Neocosmospora solani) and Fusarium spp. associated with citrus dry root rot in Morocco. Thirty-two isolates from different regions of Morocco were investigated for sensitivity to seven fungicides through the growth inhibition test. The half-maximal effective concentration (EC50) results revealed that the combination of trifloxystrobin + fluopyram and epoxiconazole were the best for the in vitro mycelial inhibition. Also, EC50 values for epoxiconazole, trifloxystrobin, fluopyram, trifloxystrobin + fluopyram, tetraconazole, thiophanate methyl, and penthiopyrade were ranging from 0.026 to 2.83 μg/ml, 2.47 to 82.35 μg/ml, 0.13 to 121.77 μg/ml, 0.37 to 14.41 μg/ml, 2.52 to 25.25 μg/ml and 2.02 to 44.88 μg/ml, respectively. The in vivo test suggested that the association between trifloxystrobin and fluopyram performed better in disease control than with other treatments' results. The evaluated fungicides showed high activity against Fusaria in vitro and demonstrated great efficacy for reducing the disease in the greenhouse trial. The study provides a basis for decision-making in the future development of new policies for preventing and controlling this disease. [ABSTRACT FROM AUTHOR]

Cercospora Leaf Spot is the most important foliar disease that affects sugar beet crops all over the world. The recent study focuses on the effect of isolation methods, light, and the culture medium on the development of Cercospora beticola Sacc. The results underlined that abundant sporulation occurred in the alternating 12-hr light/dark, but few spores were produced in the continuous darkness. The two medium PDA and SBLEA had no statistically significant effect on sporulation rate or fungal speed growth. From four isolation techniques, only the scraping by scalpel pseudostromata on old dry leaf technique has a lower rate of growth and had no sporulation in the tow media and under the tow light regime. Also, isolates collected from the four major sugar beet cultivating agro-ecologies (Gharb; Doukkala; Tadla; Moulouya), over two growing seasons (2017–2018), were characterized according to morphological and genetic traits. The genetic difference was studied by four RAPD primers and three DAMD. The outcome resulted in high band diversity depending on the used primer even for isolates from the same beet production area. The isolates showed a high diversity of morphological and molecular traits and the comparison between the classification of the two diversities did not reveal any connection between genetic and morphological diversity. Further studies may explore the source of this high genetic diversity, such as long infected seed transmission or C. beticola mycelium anastomosis. [ABSTRACT FROM AUTHOR]

Zucchini (Cucurbita pepo) and watermelon (Citrulus lanatus) rank among the most cultivated cucurbits in Morocco. These crops are prone to infection with a wide range of viral diseases responsible for tremendous losses. Field surveys carried out in 2016 and 2017 in four major cucurbit-growing areas revealed the presence of many virus-like symptoms on these crops, including severe yellowing and chlorosis. Therefore, symptomatic samples were collected and analysed serologically with DAS-ELISA for ZYMV, WMV, PRSV, CABYV and CMV and by The PCR and RT-PCR for ToLCNDV, and CVYV and MNSV, respectively. Results indicated that out of 136 samples, 79% of zucchini and 60% of watermelon samples were serologically positive for ZYMV, CMV, WMV, PRSV and CABYV. CVYV and MNSV were negatively amplified by RT-PCR using specific primer pairs. Interestingly, the PCR test revealed the occurrence of natural infection with ToLCNDV in Morocco. [ABSTRACT FROM AUTHOR]

A survey of entomopathogenic nematodes (EPN) was conducted in Morocco during 2015 and 2016 in three regions with varying topography, climate and vegetation (Meknès-El Hajeb, Ifrane and Tafilalet). EPN were isolated from 14 of 169 soil samples (8%). Molecular and morphological techniques were used for species determination. Nine samples contained heterorhabditids and five samples contained steinernematids. Eight heterorhabditids were identified as Heterorhabditis bacteriophora Poinar 1976, two steinernematids as Steinernema feltiae (Filipjev, 1934), three as belonging to the S. feltiae-group, and one as an unidentified isolate (Heterorhabditis sp.) which gives dark burgundy colour for G. mellonella cadavers. These EPNs were collected mainly from agricultural soils rather than natural habitats, with potential adaptation to specific geography, climate and soil conditions (texture, pH and organic matter content), including six EPN isolates from heavy soils. These data demonstrate that EPN are present in Moroccan soils but at relatively low frequency, so opportunity exists to augment these populations to gain biological control benefits. [ABSTRACT FROM AUTHOR]