First report of Colletotrichum gloeosporioides causing anthracnose on grapevine (Vitis vinifera) in Shaanxi province, China.

Grape anthracnose caused by Colletotrichum spp. is an economically important disease in most vineyards during rainy and humid weather. In June 2021, widespread anthracnose was observed in leaves of Vitis vinifera cv. Red Globe in Yangling city (latitude = 34.28, longitude = 108.07), Shaanxi Province. Diseased plants exhibited circular brown necrotic lesions with yellow borders in young leaves (Fig. 1A). Approximately 80% of the 75 grape plants showed disease symptoms that were consistent with those previously reported for anthracnose on grape caused by C. acutatum, C. gloeosporioides, and C. viniferum (Hong et al. 2008; Oo and Oh 2017). To isolate the pathogen, ten diseased leaves were collected. Small pieces (0.5 mm × 0.5 mm) of symptomatic tissue were surface sterilized with 75% alcohol for 30 s, transferred to 4% NaClO for 2 min, and then washed twice with sterile distilled water. The pathogen was isolated and cultured on potato dextrose agar (PDA) at 25 °C with a 12 h light/dark photoperiod. Hyphal tips of the isolate were transferred to fresh PDA after 1 day. Acervuli were formed after 15 days on PDA. The colonies were single-spored to obtain pure cultures. Pure cultures on PDA appear white to grey, and the reverse of the colonies was olive gray or yellowish white (Fig. 1B, C). Conidia were single-celled, hyaline, straight cylindrical with ends rounded, and measured 12.50 to 17.78 µm (length) (mean=15.19 µm, n=50) × 3.66 to 5.82 µm (width) (mean=4.48 µm, n=50) (Fig. 1D). The morphological characteristics matched the previous descriptions of C. gloeosporioides by Sawant et al. (2012). For molecular identification, genomic DNA was extracted from isolate YLRG13, and the actin (ACT), internal transcribed spacer (ITS), and beta-tubulin (TUB2) were amplified using the primer pairs ACT-512F/ACT-783R (Carbone and Kohn 1999), ITS1F/ITS4 (White et al. 1990), and T1/T2 (O' Donnell and Cigelnik 1997), respectively. The ACT (OQ031183 and MZ686707), ITS (OP999326 and MZ669974), and TUB2 (OQ031184 and MZ686708) nucleotide sequences of isolates YLRG5 and YLRG13 were deposited in GenBank. BLASTn showed 99 to 100% similarity with C. gloeosporioides. Neighbor-joining trees based on the three genes was constructed using PAUP version 4.0b10. The results showed the isolated YLRG5 and YLRG13 from V. vinifera was closely related to C. gloeosporioides with high bootstrap values (Fig. S2). Pathogenicity testing was performed with isolate YLRG13 by 10 µL conidial suspension (4×108 conidia/ml) on the surfaces of five wounded detached leaves of six-year-old Vitis vinifera cv. Red Globe. Sterile distilled water was used as a control. Inoculated plants were placed in a humid chamber at 25 °C. Conidial germination was observed at 24 hours post-inoculation (Fig. S1E). Four days after inoculation, typical anthracnose symptoms developed on inoculated grape leaves (Fig. S1F). No symptoms were observed on the controls. The fungus reisolated from the symptomatic grape leaves showed the same morphological characteristics of the inoculated isolate, fulfilling Koch's postulates. To our knowledge, this is the first report of grape anthracnose caused by C. gloeosporioides in Northwestern of China. C. gloeosporioides was reported causing anthracnose on a wide variety of horticultural crops, such as almond, avocado, apple, banana, cashew, citrus, cucumber, grape, guava, mango, onion, papaya, passion fruit, pepper, strawberry, tomato, and watermelon (Sharma and Kulshrestha 2015), suggesting the potential cross-infection between grape and other horticultural crops.

[Functional analysis of autophagy-related gene Atg6 in planarian central nervous system regeneration].

Autophagy-related gene 6 (Atg6) plays an essential role in autophagy, and loss of its function impairs neurogenesis. Planarian is a good model for the study of the central nervous system (CNS) regeneration. It can regenerate a new head de novo in 1 week following decapitation. Therefore, functional analysis of Atg6 in planarian CNS regeneration is very important for understanding of autophagy in the regulation of neurogenesis. In this work, we reported the molecular characteristics of Atg6 in Dugesia japonica (DjAtg6) for the first time and examined its function by RNAi. The full-length cDNA of DjAtg6 is 1366 bp encoding 423 amino acids. The deduced amino sequence of DjAtg6 contains the coil-coil domain and ß-α-repeated autophagy-specific domain shared by ATG6/Beclin 1 family. Following amputation before and after the pharynx, DjAtg6 transcripts increased and were mainly distributed in the newly regenerated brain structure. RNAi-DjAtg6 delayed planarian head regeneration with a small size of brain, and decreased the expression levels of neural-related genes. In addition, our results revealed that RNAi-DjAtg6 did not affect the stem cell proliferation, but down-regulated the cell migration-related genes mmp1 and mmp2. Furthermore, RNAi-mmp1 and RNAi-mmp2 delayed planarian head regeneration. Therefore, our results suggest that DjAtg6 is important for planarian CNS regeneration. The abnormal CNS regeneration caused by RNAi-DjAtg6 may be related to cell migration, but the detailed mechanism needs to be further investigated.

Effects of inorganic electrolyte anions on enrichment of Cu(II) ions with aminated Fe3O4/graphene oxide: Cu(II) speciation prediction and surface charge measurement.

The present work evaluated the effects of six inorganic electrolyte anions on Cu(II) removal using aminated Fe3O4/graphene oxide (AMGO) in single- and multi-ion systems. A 2(6-2) fractional factorial design (FFD) was employed for assessing the effects of multiple anions on the adsorption process. The results indicated that the Cu(II) adsorption was strongly dependent on pH and could be significantly affected by inorganic electrolyte anions due to the changes in Cu(II) speciation and surface charge of AMGO. In the single-ion systems, the presence of monovalent anions (Cl(-), ClO4(-), and NO3(-)) slightly increased the Cu(II) adsorption onto AMGO at low pH, while the Cu(II) adsorption was largely enhanced by the presence of SO4(2-), CO3(2-), and HPO4(2-). Based on the estimates of major effects and interactions from FFD, the factorial effects of the six selected species on Cu(II) adsorption in multi-ion system were in the following sequence: HPO4(2-)>CO3(2-)>Cl(-)>SO4(2-)>NO3(-)=ClO4(-), and the combined factors of AD (Cl(-)×SO4(2-)) and EF (Cl(-)×SO4(2-)) had significant effects on Cu(II) removal.

Effects of background electrolytes and ionic strength on enrichment of Cd(II) ions with magnetic graphene oxide-supported sulfanilic acid.

To elucidate the influence mechanisms of background electrolytes and ionic strength on Cd(II) removal, the adsorption of Cd(II) onto magnetic graphene oxide-supported sulfanilic acid (MGO-SA) in aqueous solutions containing different types and concentrations of background electrolytes was studied. The results indicate that Cd(II) adsorption was strongly dependent on pH and could be strongly affected by background electrolytes and ionic strength. The Cd(II) removal was decreased with the presence of background electrolyte cations (Na(+), K(+), Ca(2+), Mg(2+), Mn(2+), Zn(2+), and Ni(2+)), and the divalent cations exerted more obvious influences on the Cd(II) uptake than the monovalent cations at pH 6. Both Cl(-) and NO3(-) had negative effects on Cd(II) adsorption because they can form water-soluble metal-anion complexes with Cd(II) ions. The presence of 0.01molL(-1) Na3PO4 reduced the removal percentage of Cd(II) at pH<5 but extremely enhanced the Cd(II) removal when the pH>5. The Cd(II) adsorption was sensitive to changes in the concentration of NaCl, NaNO3, NaClO4, and Na3PO4. Besides, the adsorption isotherm of Cd(II) onto MGO-SA could be well described by the Freundlich model and was also influenced by the type of background electrolyte ions and the ionic strength.