First Report of White Leaf Spot Caused by Hypomontagnella monticulosa on Pachira glabra in China.

Pachira glabra Pasq. is an ornamental tree widely distributed in tropical and subtropical regions of China. In August 2021, an unknown leaf spot was observed on P. glabra in Xiangtan County, Hunan, China (27.976°N, 113.041°E). Over 1,200 plants were evaluated, and up to 20% of the plants were diseased. In moderately diseased plants, approximately one third of leaves had symptoms with the disease severity estimated to be 31.6 ± 9.4% (n=100). The symptoms first appeared as pale yellow to yellow small dots often confined between leaf veins. These dots gradually enlarged, and coalesced into large pale or white spots with brown borders and yellow halo. In severe infections, early leaf death and defoliation occurred. Thirty lesions (2 × 2 mm) collected from ten trees were sterilized in 75% ethanol for 15 s, 5% sodium hypochlorite for 15 s, rinsed in sterile water three times, placed on oatmeal agar medium (OA) plate with lactic acid (3 ml/liter), and incubated at 28°C for 15 days. After incubation, five isolates with a similar morphology were obtained by single-spore culture. Colonies on OA were white and then turned pale grey. Pigments on the reverse side were pale brown. Conidiophores were hyaline, smooth to finely roughened, usually with virgariella-like branching patterns. Conidiogenouscells were hyaline, smooth, and measured 13.9 to 53.8 long and 1.5 to 2.3 µm wide (average 30.8 × 2.0, n=50). Conidia were single-celled, transparent, smooth, ellipsoid to obovoid, 2.3 to 4.6 × 1.7 to 3.1 µm (average 3.1 × 2.3, n=100) in measurement. For further molecular identification, internal transcribed spacer (ITS), ß-tubulin (TUB2), RNA polymerase II (RPB2), and large ribosomal subunit (LSU) genes of a representative isolate TT422 were amplified from genomic DNA, using primers ITS1/ITS4 (Mills et al. 1992), T1/T22 (O'Donnell et al. 1997), RPB2-5F/7cR (Liu et al. 2000), and LROR/LR7 (Rehner et al. 1994), respectively. Sequences of ITS (accession no. OM070368), TUB2 (OM201746), LSU (OM070369), and RPB2 (OM141478) from the isolate TT422 showed >98% identity where sequences overlapped to the reference strain of Hypomontagnella monticulosa MUCL 54604 (KY610404, KX271273, KY624305, and KY610487). Concatenated sequences were used for a phylogenetic analysis based on Maximum Likelihood using MEGA7. Based on morphological and molecular data, the isolate TT422 was identified as H. monticulosa (Ju & Rogers 1995; Lambert et al. 2019). Pathogenicity tests were performed three times on healthy leaves using the isolate TT422. Three leaves on one-year-old plants were slightly wounded by a sterile needle, and sprayed with conidial suspension (1×106 conidia/ml, containing 0.05% Tween 20) . Control leaves were sprayed with sterile water containing 0.05% Tween 20. All plants were kept in a greenhouse for 24 h at 28°C and 80% relative humidity, with a 16-h photoperiod and then transferred to natural conditions. All inoculated leaves developed white leaf spot symptoms after 7 days similar to those observed in the field, whereas no visible symptoms appeared on the control leaves. H. monticulosa strains were reisolated from all symptomatic leaves, fulfilling Koch's postulates. H. monticulosa isolated from marine or endophytic origin has been reported to produce bioactive metabolites with anticancer and microbial activities (Leman-Loubière et al. 2017; Lutfia et al. 2021; Zhang et al. 2021), but not as a phytopathogen. To our knowledge, this is the first report of H. monticulosa causing white leaf spot on P. glabra in China and worldwide.

First Report of Colletotrichum siamense Causing Leaf Anthracnose on Pachira glabra in China.

Pachira glabra Pasq.is an important landscape tree in southern China due to its ornamental value. Between March and April - 2021, anthracnose-like symptoms on P. glabra leaves were found in the botanical garden (27.904°N, 112.918°E) of Hunan University of Science and Technology located in Xiangtan of Hunan Province. Over 700 plants were evaluated, and up to 30% of the plants were symptomatic. On each plant, approximately 22% leaves had symptoms. Disease severity was estimated to be 15.6 ± 6.1% (n=100) in moderately diseased plants. Initially, subcircular or irregular shaped, water-soaked spots with pale green to yellow centers appeared mostly along leaf margins. Later, theses spots turned light brown to dark brown with black borders, gradually enlarged, and often coalesced into large sunken, necrotic areas, leading to early leaf death and abscission. Thirty lesions (2 × 2 mm) collected from ten trees were sterilized in 75% ethanol for 10 s, 2% sodium hypochlorite for 30 s, rinsed in sterile water three times, placed on potato dextrose agar (PDA) with lactic acid (3 ml/liter), and incubated at 28°C for 5 days. After incubation, six isolates with a similar morphology were obtained by single-sporing. Colonies on PDA were white and with age produced a light brown pigmentation on the underside of the colony. Acervuli present in aged cultures, brown to black, circular to subcircular and measured 31.9 to 108.7 µm (71.4 ± 6.2 µm, n=30). Conidia were single-celled, transparent, smooth, fusiform to cylindrical with obtuse to slightly ronded ends, and measured 7.8 to 11.1 µm long and 2.5 to 3.1 µm wide (9.3 ± 1.0 × 2.9 ± 0.7, n=100). For further molecular identification, Internal transcribed spacer (ITS), actin (ACT), glyceraldehyde-3-phosphate (GAPDH), calmodulin (CAL), and beta-tubulin (TUB2) genes of the isolates were amplified from genomic DNA, using primers ITS1/ITS4 (Mills et al. 1992), GDF/GDR (Cannon et al. 2012), ACT-512F/ACT-783R, CL1CF/CL2CR (Weir et al. 2012), and T1F/T22R (O'Donnell et al. 1997), respectively. Sequences of ITS (accession no. OM074029), ACT (OM190777), GAPDH (OM190778), CAL (ON210110), and TUB2 (ON210109) from CS-1 showed >98% identity where sequences overlapped to the reference strain of Colletotrichum siamense CBS 130420 (JX010259.1, JX009549.1, JX009974.1, JX009713.1 and JX010415.1). Concatenated sequences were used for a phylogenetic analysis based on Maximum Likelihood using MEGA-X. Based on morphological and molecular data, isolate CS-1 was identified as C. siamense (Cannon et al. 2012). . Pathogenicity tests were performed three times on healthy leaves using isolate CS1. Ten leaves on one-year-old plants were either slightly wounded by a sterile needle or unwounded, and inoculated with 10 µl of conidial suspension (1×106 conidia/ml, containing 0.05% Tween 20) per wound. The control plants were treated with sterile water. All plants were kept in a greenhouse for 24 h at 28°C and 80% relative humidity, with a 12-h photoperiod and then transferred to natural conditions. All wounded, inoculated leaves developed leaf spot symptoms after 14 days similar to those observed in the field, whereas no visible symptoms appeared on the intact and noninoculated leaves. C. siamense strains were reisolated from all symptomatic leaves, fulfilling Koch's postulates. C. siamense has been reported as a causal agent of anthracnose associated with diverse species (Udayanga et al. 2013), but not including P. glabra. To our knowledge, this is the first report of C. siamense causing anthracnose on P. glabra.

Reversible splenial lesion syndrome with mental disorders as only manifestation.

BACKGROUND: Reversible splenial lesion syndrome (RESLES) was reported to be associated with variable entities. However, much less is known about the cases in which the mental disorders act as the only manifestation. METHOD: Total ten patients of RESLES were obtained in this retrospective study from Shenzhen Kangning Hospital. T1-fluid attenuated inversion recovery (T1-FLAIR), T2-weighted images, T2-FLAIR, diffusion-weighted images and apparent diffusion coefficient map were performed on all the patients. Clinical manifestations, laboratory examination results, magnetic resonance imaging (MRI) findings, treatments and outcomes were analyzed. RESULT: All patients showed different mental disorders as the only manifestation. There were two cases of alcohol abuse, one of Asperger's syndrome with malnutrition, one of infection and one of invasive pituitary adenoma. The other cases were diagnosis as major depressive disorder, dissociative and conversion disorders, undifferentiated somatoform disorder, unspecified psychosis and bipolar disorder, respectively. Three patients were completely recovered while the clinical symptoms of rest seven patients partially recovered at the follow-up three months later. Oval-shaped lesion centered on the splenial of corpus callosum (SCC) was observed in all patients using MRI. The lesions of SCC of all patients were completely resolved within five weeks. CONCLUSIONS: We found that RESLES might only showed mental symptoms. On the one hand, for the patients with acute mental disorders, clinicians should be alert to the possibility of RESLES caused by physical disease. On the other hand, we suggest that mental disorder might be a precipitating factor of RESLES.

Clinical characteristics and neuroimaging findings of seven patients with Dyke Davidoff Masson syndrome.

BACKGROUND: DDMS is a rare disease diagnosed by clinical and radiological characteristics. But the complexity of radiological and clinical manifestations of DDMS has become a challenge diagnostically. To date, the reported cases with DDMS had highly varied clinical manifestations including seizures, contralateral hemiplegia/hemiparesis, facial asymmetry, mental retardation, etc. In addition to typical clinical findings, some new characteristics have been recently added to the spectrum of DDMS. However, few cases have been reported to be associated with neuropsychiatric symptoms according to the literature. This study aimed to investigate the neuropsychiatric manifestations associated with Dyke-Davidoff-Masson syndrome (DDMS) and related imaging findings. METHODS: This study included 7 patients diagnosed with DDMS between 2014 and 2020. The clinical characteristics, neuropsychiatric manifestations, and radiological results were retrospectively evaluated. RESULTS: Seven patients (five males and two females) with a mean age of 28.0 ± 9.73 (range 15.0-41.0) years were included. Five patients were admitted to the psychiatric unit due to psychological and behavioral disorders. Two patients were referred to the neurology unit mainly due to epilepsy. Six patients had epileptic seizures, 4 had hemiplegia, 3 had mental retardation, 2 patients had external ear deformities, and 2 had facial asymmetry. Neuropsychiatric symptoms were presented in 6 (85.7 %) cases. Cases 2-6 developed affective disorders. Deficits in verbal communication, impairment of social interaction, lack of insight, adulia and hypobulia appeared in cases 1-4. Schizophrenia with apathy, and epileptic schizoid psychosis were observed in cases 4 and 5 respectively. Case 6 had behavioral disorders, hyperactivity, tic disorder, mental retardation, anxiety, catatonic symptoms and suicidal tendency. Case 7 had seizures and mental retardation, and no psychiatric symptoms were presented. Radiological examinations showed unilateral cerebral atrophy, enlarged lateral ventricles, and various compensatory hypertrophy of the skull in all cases. The midline structure has shifted to the affected side in 5(71.4 %) cases. Atrophy of the basal ganglia or brain stem was observed in 4(57.1 %) cases. CONCLUSIONS: The hallmark imaging manifestations of DDMS facilitated the diagnosis in most cases. This study illustrated that a variety of psychoneurotic disorders and ear abnormalities were correlated with DDMS.