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Since 2017, a new leaf wilt syndrome was observed in plantations of date palm in Tunisia. Its incidence increases sharply from year to year, especially in ‘Deglet Nour’ trees, aged between 5 and 15 years. In severe cases, the large number of dried leaves per tree can lead to complete cessation of date production. Symptoms appear on one or more leaves in the center of the crown. Whitening and drying start at the top of the leaflets and proceed to their base, while the midrib remains green. Then the whole leaf dies. Small white-creamy leaflet fragments and roots were collected from five different regions in the Djerid Oases. They were disinfected with diluted bleach (0,8 % NaOCl) and ethanol (80%) (each 2 min), rinsed with sterile distilled water, dried and finally plated in Petri dishes containing Potato Dextrose Agar (PDA) amended with 50mg/l neomycin. see more After incubation for 7 days at 25ºC±2, emerging fungal colonies were single-spored by serial dilution. They were transferred to PDA, Carnation Leaf Agar (CLA) 2 °C and 70% R.H.. Isolates of F. proliferatum led to dryness and wilting leaflets after 3 weeks. Fusarium brachygibbosum only induced mild leaf yellowing, while in combination they were more virulent. Fungal isolates of both species were re-isolated and their identity confirmed to be the same of those isolated from leaflets infected in the open field, confirming Koch’s postulates. Control plants lacked symptoms. Fusarium proliferatum is known as date palm pathogen in many countries (Saleh et al. 2017), however, to our knowledge, this is the first report of F. proliferatum and also F. brachygibbosum causing Leaf Wilt symptoms on P. dactylifera in Tunisia.The dagger nematode Xiphinema index has a major economic impact due to its transmission of Grapevine fanleaf virus (GFLV) to grapevines. This vector nematode, which was introduced into Western countries from the Middle East together with the domesticated grapevine, mostly reproduces by meiotic parthenogenesis, but microsatellite multilocus genotype (MLG) analysis has revealed the occurrence of rare sexual reproduction events in field conditions. In a previous six-year study under controlled conditions, we evaluated the durability of resistance (R) to X. index in accessions derived from a muscadine R source and reference accessions. In this previous study, we used an equal-proportion mixture of four lines (from Spain, Italy, Greece and Iran) representative of X. index diversity as the inoculum, and we collected random samples in three-, four-, five- and six-year-old vines. Here, we genotyped the individuals from these samples using MLG technique, and we analyzed the changes in line frequency and the occurrence of sexual reproduction events between lines over time. The nematode lines differed in aggressiveness and hybrids between lines were detected at a low, but apparently increasing rate. Hybridization events were recovered in all accessions, regardless of resistance status and propagation type. Finally, our data provide the first evidence of sexual reproduction in the nematode X. index under controlled conditions.Barley yellow mosaic disease, caused mainly by barley yellow mosaic virus (BaYMV) and barley mild mosaic virus (BaMMV), is a devastating disease of barley and is a threat to Eurasian barley production. Early detection is essential for effective management of the pathogens and to assure food security. In the present study, a simple, rapid, specific, sensitive, and visual method was developed to detect BaYMV using loop-mediated isothermal amplification (LAMP). Two pairs of oligonucleotide primers (inner and outer primers) were designed to amplify the gene encoding the coat protein of BaYMV. The optimal conditions for the LAMP method were determined, and a one-step reverse transcription (RT)-LAMP method was also developed. Subsequently, the fastest processing time for RT-LAMP was determined. Among eight plant viruses examined using the LAMP method, only BaYMV was detectable, suggesting that the assay was highly specific. The RT-LAMP method was ten times more sensitive than the RT-PCR method in the sensitivity test. To further shorten the virus detection process, a dye was added to the RT-LAMP products, and positive reactions were simply read by the naked eye via a color change (from orange to light green) under visible light. Barley samples from the middle and lower reaches of the Yangtze River basin, where barley yellow mosaic disease broke out very seriously in 1970s, were detected by the newly established RT-LAMP method. The results showed that all samples were positive for BaYMV, indicating that the potential risk of the virus in these areas. This newly established LAMP/RT-LAMP method could be a promising tool for barley protection and food security control.Pythium aphanidermatum is the predominant species causing Pythium root rot of commercially grown poinsettia (Euphorbia pulcherrima Willd. ex Kotzch) in North Carolina. Pythium root rot is managed primarily through a combination of sanitation practices and preventative fungicide applications of mefenoxam or etridiazole. Insensitivity to mefenoxam is common but growers continue to rely on it due to lack of inexpensive and efficacious alternatives. This research was conducted to identify alternative fungicides for Pythium root rot control and evaluate their efficacy on poinsettia cultivars with varying levels of partial resistance. Greenhouse studies were conducted to assess efficacy of fungicide treatments in seven poinsettia cultivars inoculated with a mefenoxam-sensitive isolate of P. aphanidermatum. One study examined control with a single fungicide drench made at transplant and a second study examined repeat fungicide applications made throughout the experiment. Treatments containing etridiazole, mefenoxam, provide guidelines for selecting fungicides to maximize control of Pythium root rot on poinsettia cultivars.Salvia miltiorrhiza Bunge is a herb plant used as a traditional Chinese medicine to cure cardiovascular disease. In December 2018, a root rot disease was observed on S. miltiorrhiza in four surveyed counties (Song, Yuzhou, Fangcheng, and Mianchi) in Henan province in China. The disease incidence ranged from 15 to 50% in 12 surveyed fields. At the early stage, the diseased plants were wilting with purple leaves. Leaves and branches became withered and fibrous roots became brown and rotted. The main roots of severely diseased plants also became rotted. The color of the stem surface turned from red to black, and the color of the stem xylem and phloem turned from dark red to brown. Eventually, the roots of diseased plants became completely rotted and the whole plants became dead, but no stink, which is different from Fusarium solani (Mart.) Sacc. (Yuan et al. 2015). Diseased root tissues (5×5×5 mm in size) were cut from diseased plants, surface-sterilized with 1% sodium hypochlorite for 1 min followed by dipping in 75% alcohol for 30 sec, rinsed in sterile distilled water for 3 times, air-dried on a sterilized filter paper in a laminar flow hood, placed on potato dextrose agar (PDA) containing 250 mg/l of streptomycin sulfate, and incubated at 28℃.