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Colletotrichum species are destructive pathogens, saprobes and endophytes on various plant hosts. However, the species occurring on walnut remains largely unresolved. Walnut leaf spot occurred seriously in orchards of Xingshan County, Hubei Province in China. To determine Colletotrichum spp. associated with Juglans regia, 22 isolates were obtained from the diseased leaf samples collected during 2019 and 2020. Seven isolates were further selected as representatives based on morphology and phylogeny using ITS, GAPDH, CHS-1 and ACT gene regions. The results revealed that the isolates belonged to two phylogenetic species complexes, C. gloeosporioides species complex (CGSC) comprising C. gloeosporioides and C. kahawae, and C. acutatum species complex (CASC) including C. nymphaeae, C. godetiae, C. fioriniae and a new species, namely Colletotrichum juglandis sp. nov.. Among them, C. kahawae was firstly reported from walnut.

To distinguish between the normal $q\bar q$ and exotic diquark-antidiqark ($q^2\bar q^2$) contents of the lowest-lying scalar meson ($S_0$), we investigate the semileptonic $D\to S_0 e^+\nu_e, S_0\to M_1 M_2$ decays, where $M_{1(2)}$ represents a pseudoscalar meson. With the form factors extracted from the current data, we calculate ${\cal B}(D_s^+\to \sigma_0 e^+\nu_e,\sigma_0\to\pi^0\pi^0) =(12.9^{+6.3}_{-4.9})\times 10^{-4}$ and $(0.8^{+1.2}_{-0.7})\times 10^{-4}$ for the $q\bar q$ and $q^2\bar q^2$ quark structures, respectively, and compare them to the experimental upper limit: $6.4\times 10^{-4}$. It is clearly seen that $S_0$ prefers to be the $q^2\bar q^2$ bound state. Particularly, ${\cal B}_{q\bar q}(D_s^+\to \sigma_0 e^+\nu_e,\sigma_0\to\pi^+\pi^-) =(25.8^{+12.5}_{-\;\,9.8})\times 10^{-4}$ and ${\cal B}_{q^2\bar q^2}(D_s^+\to \sigma_0 e^+\nu_e,\sigma_0\to\pi^+\pi^-) =(1.5^{+2.4}_{-1.3})\times 10^{-4}$ are predicted to deviate far from each other, useful for a clear experimental investigation., Comment: 10 pages, 1 figure, 1 table

Colletotrichum juglandis X. Wei & J.X. Deng, sp. nov. Fig. 3 MycoBank No: 843086. Etymology: In reference to the host genus name, Juglans. Type. China, Hubei Province, Yichang city, Xingshan county on infected leaves of Juglans regia. 11 July, 2019, J. X. Deng (ex-type culture YZU 191277) Description: Colonies on PDA attaining 47–52 mm diam. after 7 days at 25 °C, whitish to gray, dense, aerial mycelium with masses of conidial ooze. Conidia on SNA unicellular, hyaline, smooth-walled, aseptate, straight, subcylindrical to fusiform with one end round and one end slightly acute, 6–15×2–5 μm (av.: =10.8×4.1, n =50). Appressoria single, brown to dark brown, smooth-walled, variable in shape, irregular unlobed or slightly lobed, 6–17× 4–10 μm (av.: =9.3×6.4, n =30). Chlamydospores formed laterally on hyphae. Setae absent. Sexual morph not observed. Materials examined: China, Hubei Province, Yichang City, Xingshan County, Walnut orchard, from the leaf of Juglans regia anthracnose 11 July, 2020, X. Wei, living cultures YZU 191277 and YZU 201192. Note: This species belongs to C. acutatum species complex (Fig. 1) and forms a mono-lineage in a clade comprising C. chrysanthemi, C. cosmi, C. guajavae, C. nymphaeae, C. scovillei, and C. walleri with 1.0/100% (PP/BS) values. It is phylogenetically close related to C. nymphaeae, C. guajavae, C. scovillei and C. chrysanthemi. Morphologically, it is readily differentiated with C. chrysanthemi by conidia shape and distinct from the other three species by producing larger appressoria (Table 2). In addition, C. guajavae and C. scovillei produce conidia with acute ends (Damn et al. 2012a), which is not observed in this species. Pathogenicity tests Pathogenicity tests revealed that Colletotrichum juglandis sp. nov. from Juglans regia could induced necrotic symptoms on living leaves by the spore suspension of isolate YZU 191277. After 7 days, the disease symptoms caused by spore suspension were around 4.3 mm in diameter (Fig. 3B), while symptomless on controls. After re-isolation, the same pathogen was obtained and identified based on morphology., Published as part of Wei, Xin, Yang, Shu Qi, Jiang, Zhi Gang, Cui, Meng Jiao, Deng, Jian Xin & Zhang, Yi, 2022, Colletotrichum juglandis sp. nov. (Ascomycota: Glomerellaceae) associated with walnut leaf spot in China, pp. 256-268 in Phytotaxa 556 (3) on pages 263-264, DOI: 10.11646/phytotaxa.556.3.2, http://zenodo.org/record/6972824

A study on the two-band observations of the millisecond pulsar J0437- 4715 is carried out based on the radio data of the Parkes Observatory of Australia and the X-ray data obtained with the ASM (All Sky Monitor) in the RXTE (Rossi X-ray Timing Explorer). For the radio observations of J0437-4715 the software TEMPO2 is applied to the calibration of the timing data of different terminal systems, thereby improving the accuracy of the timing model. By taking advantage of the all-weather observations of the ASM in the RXTE, the study of the medium- and long-term light variations of the pulsar J0437-4715 at the X-ray wavelengths is carried out by means of structure function, and it is found that this pulsar has a 620 d light period in the X-ray waveband.