First report on zircon U-Pb age of the quartz monzonite from the Pandian skarn iron deposit in the Luxi area, Eastern China

Canadian goldenrod (Solidago canadensis L., Asteraceae) is a rhizomatous perennial plant native to North America that has invaded eastern China and continues to spread northward and westward. It is quite common on field borders, roadsides, and in undeveloped areas, posing a serious threat to native ecosystems and their biodiversity. During the late summers of 2007 and 2008, wilted Canadian goldenrod plants were occasionally found in invasive populations in the suburb of Nanjing city. Wilted plants were transplanted and maintained in a greenhouse at Nanjing Agricultural University. A white mass of fungal hyphae, which grew on the soil surface around the stem of the symptomatic S. canadesis plants and eventually covered the stem, was observed. Initially, the base of the stem became yellow, turned brown, and the light brown discoloration extended up the stem to a height of 3 to 7 cm. The leaves then collapsed, starting from the top until the entire plant wilted. The fungus produced numerous, small, roundish sclerotia of uniform size (0.7 to 2.0 mm in diameter), which were white at first and then became brown to dark brown. The fungus grew into the stems and downward into the rhizome area, but no sclerotia were detected inside the stem or root. Diseased tissue with sclerotia was disinfested for 1 min in 1% NaOCl and plated on potato dextrose agar amended with 100 mg/liter of streptomycin sulfate. On the basis of sclerotia morphology and the presence of clamp connections at hyphal septa, the fungus was identified as Sclerotium rolfsii. Pathogenicity of the isolate was confirmed by inoculating 1-year-old S. canadensis plants (average 1.5 m high) grown in pots. The inoculum consisted of cottonseed hulls infested with mycelium and sclerotia of the pathogen and was placed on the soil surface around the base of each unwounded plant. Noninoculated plants served as controls. The pathogenicity test was conducted twice. After inoculation, the plants were maintained at high humidity and 30°C for 3 days and then transferred to a greenhouse. All inoculated plants developed symptoms of southern blight. Inoculated plants developed symptoms of wilting 5 to 7 days after inoculation and were completely wilted within 15 to 20 days. Symptoms of wilting were soon followed by the appearance of white-to-light brown sclerotia on the collar region. Control plants remained symptomless and Sclerotium rolfsii was reisolated from inoculated plants. To our knowledge, this is the first report of southern blight of Canadian goldenrod caused by Sclerotium rolfsii in China.

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First Report of Colletotrichum karstii Causing Glomerella Leaf Spot on Apple in Santa Catarina State, Brazil

Plant Disease ◽

10.1094/pdis-05-13-0498-pdn ◽

2014 ◽

Vol 98 (1) ◽

pp. 157-157 ◽

Cited By ~ 14

Author(s):

A. C. Velho ◽

M. J. Stadnik ◽

L. Casanova ◽

P. Mondino ◽

S. Alaniz

Keyword(s):

United States ◽

Leaf Spot ◽

Management Practices ◽

Eastern China ◽

The United States ◽

Subtropical Climate ◽

Santa Catarina ◽

First Report ◽

Glomerella Leaf Spot ◽

Santa Catarina State

Glomerella leaf spot (GLS) is an emerging disease of apple (Malus domestica Borkh.) that has been reported in regions with a humid subtropical climate, such as southern Brazil, the southeastern United States, and more recently eastern China. GLS is favored by high humidity and temperatures between 23 and 28°C and can result in extensive defoliation when the severity is high. The disease was first reported 1988 in Brazil on cvs. Gala and Golden Delicious in orchards in Paraná State (3), but now is widespread in the country's producing areas. Two Colletotrichum species of different complexes have been associated with GLS, C. gloeosporioides (Penz.) Penz. & Sacc. and its sexual stage Glomerella cingulata (Stoneman) Spaulding & Scherenk, and C. acutatum J. H. Simmonds, although GLS is more commonly associated with the former. In the summer of 2012, necrotic spots were observed on apple leaves (cv. Gala) in Santa Catarina state, Brazil. The first symptoms were reddish-brown spots, evolving to small necrotic lesions 1 to 10 mm long at 7 to 10 days after symptoms were first noted. Pure cultures were obtained by monosporic isolation and grown on PDA at 25°C and with a 12-h photoperiod under fluorescent light. The color of the upper surface of the colony varied from white to gray and the reverse was pink. The conidia length and width ranged from 9.1 to 17.1 μm ([Formula: see text] = 12.8) and from 2.9 to 6.8 μm ([Formula: see text] = 4.9), respectively, and were cylindrical, hyaline, and straight. After germination, conidia formed oval or circular appressoria measuring between 4.0 and 10.0 ([Formula: see text] = 6.3) × 3.0 and 9.0 ([Formula: see text] = 5.7). To confirm pathogenicity, susceptible apple seedlings (cv. Gala) were inoculated with a suspension of 1 × 106 conidia.mL–1. Seedlings sprayed with sterile distilled water served as controls. Seedlings were incubated in a moist chamber at 25°C and 100% RH for 48 h. First symptoms appeared 4 days after inoculation and were similar to those observed in the field. The control treatment remained symptomless. The pathogen was reisolated from lesions, confirming Koch's postulates. Fungus was molecularly characterized by sequencing the internal transcribed spacer (ITS) rDNA and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and the nucleotide sequence was deposited in the GenBank database (KC876638 and KC875408). C. karstii, considered as part of the C. boninense species complex (1), was identified with 100% sequence homology. This species was previously reported in China (4), Thailand, and the United States, affecting Orchidaceae plants (2), and in Brazil it has been reported affecting Carica papaya, Eugenia uniflora, and Bombax aquaticum (1). To our knowledge, this is the first report of C. karstii causing GLS on apple in Brazil. The development of pre-harvest management practices may be warranted to manage this disease. References: (1) U. Damm et al. Stud. Mycol. 73:1, 2012. (2) I. Jadrane. Plant Dis. 96:1227, 2012. (3) T. B. Sutton. Plant Dis. 82:267, 1998. (4) Y. Yang. Cryptogamie Mycologie 32:229, 2011.

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First Report of the Soybean Cyst Nematode, Heterodera glycines, on Soybean in Zhejiang, Eastern China

Plant Disease ◽

10.1094/pdis-93-3-0319b ◽

2009 ◽

Vol 93 (3) ◽

pp. 319-319 ◽

Cited By ~ 4

Author(s):

J. Zheng ◽

Y. Zhang ◽

X. Li ◽

L. Zhao ◽

S. Chen

Keyword(s):

Soybean Cyst Nematode ◽

Heterodera Glycines ◽

Eastern China ◽

Mainland China ◽

Its Region ◽

Cyst Nematode ◽

Northeastern China ◽

First Report ◽

Soybean Plants ◽

Two Populations

The soybean cyst nematode (SCN), Heterodera glycines Ichinohe, is a destructive pest of soybean. Damage to soybean by SCN was first reported from northeastern China in 1899 (1). SCN has been documented in Anhui, Beijing, Hebei, Heilongjiang, Henan, Jiangsu, Jilin, Liaoning, Neimenggu, Shaanxi, Shandong, and Shanxi provinces in mainland China (1). These provinces are situated in the Heilongjiang and Songhuajing valleys in northeastern China and the eastern region of the Yangtze and Yellow rivers in northern China and have cold to temperate climates. In June of 2008, cyst-forming nematodes were detected in two soybean-growing areas of Hangzhou and Xiaoshan in Zhejiang Province, in subtropical eastern China. The soybean plants at the Hangzhou site showed symptoms of stunting and chlorosis, whereas no aboveground or root symptoms were observed on soybean plants at the Xiaoshan site, except for the presence of SCN females on the roots. The two populations had the same morphological and molecular characters. The cysts were lemon shaped with posterior protuberance, ambifenestrate, underbridge and bullae strongly developed, and lateral field of second-stage juveniles consisted of four incisures. The key morphometrics of cysts were fenestra length (41 to 52 μm) and width (33 to 48 μm), vulval silt (47 to 55 μm), and underbridge length (79 to 94 μm), all of which were coincident with that of SCN (2). Amplification of rDNA-internal transcribed spacer (ITS) region using primers TW81 (5′-GTT TCC GTA GGT GAA CCT GC-3′) and AB28 (5′-ATA TGC TTA AGT TCA GCG GGT-3′) yielded a PCR fragment of approximately 1,030 bp. The digestion patterns of the PCR fragments of the ITS region with AluI, AvaI, CfoI, MvaI, and RsaI showed identical restriction profiles to H. glycines (3), and the sequences exhibited 100% similarity with those of H. glycines isolates, Accession No. AY667456 from GenBank. Morphological and molecular identification confirmed that the two populations of cyst-forming nematodes from Zhejiang are SCN. To our knowledge, this is the first report of SCN in Zhejiang, now the most southern location in mainland China with confirmed infestation of SCN. References: (1) Z. X. Liu et al. Int. J. Nematol. 7:18, 1997. (2) R. H. Mulvey. Can. J. Zool. 50:1277, 1972. (3) J. Zheng et al. Russ. J. Nematol. 8:109, 2000.

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First Report of Peach Brown Rot Caused by Monilinia fructicola in Central and Western China

Plant Disease ◽

10.1094/pdis-03-13-0310-pdn ◽

2013 ◽

Vol 97 (9) ◽

pp. 1255-1255 ◽

Cited By ~ 2

Author(s):

L. F. Yin ◽

S. N. Chen ◽

N. N. Yuan ◽

L. X. Zhai ◽

G. Q. Li ◽

...

Keyword(s):

Prunus Persica ◽

Direct Sequencing ◽

Eastern China ◽

Morphological Characteristics ◽

Brown Rot ◽

Its Sequences ◽

Western China ◽

Its2 Region ◽

Monilinia Fructicola ◽

First Report

Brown rot of peach (Prunus persica) in China has been reported to be caused by at least three Monilinia species (1). In the present study, peaches with symptoms resembling brown rot caused by Monilinia species were collected from commercial orchards in the northwestern province of Gansu in August 2010, the southwestern province of Yunnan in July 2011, and in the central province of Hubei in July 2012. Affected fruit showed the typical symptoms of brown rot with zones of sporulation. Fungal isolates were single-spored and cultured on potato dextrose agar (PDA). Colonies showed grayness with concentric rings of sporulation after incubation at 25°C in the dark. Mean mycelial growth of isolates YHC11-1a and YHC11-2a from Yunnan, GTC10-1a and GTC10-2a from Gansu, and HWC12-14a and HWC12-23a from Hubei, was 4.6 ± 0.4 and 7.5 ± 0.7 cm after 3 and 5 days incubation, respectively. Conidia were lemon shaped and formed in branched monilioid chains, and the mean size was 9.3 (6.7 to 11.5) × 12.5 (7.9 to 17.8) μm, which was consistent with the characteristics of Monilinia fructicola (1,2). The species identification was confirmed by sequencing of the ribosomal ITS sequences. The ribosomal ITS1-5.8S-ITS2 region was amplified from each of the six isolates using primers ITS1 and ITS4 (3). Results indicated that the ITS sequences of these isolates were identical and showed the highest similarity (100%) with M. fructicola ITS sequences from isolates collected in China (GenBank Accession Nos. HQ893748, FJ515894, and AM887528), Slovenia (GU967379), Italy (FJ411109), and Spain (EF207423). The pathogen was also confirmed to be M. fructicola based on the detection of an M. fructicola- specific band (534 bp) using a PCR-based molecular tool developed for distinguishing Chinese Monilinia species affecting peach (1). Pathogenicity was tested on surface-sterilized, mature peaches (Shui Mi Tao) with representative isolates. Fruits were holed at three equidistant positions to a depth of 5 mm using a sterile cork borer. Mycelial plugs (5 mm in diameter) from the periphery of a 4-day-old colony of each isolate were placed upside down into each hole, control fruits received water agar. After 3 days of incubation at 22°C in a moist chamber, inoculated fruits developed typical brown rot symptoms while control fruits remained healthy. Pathogens from the inoculated fruit were confirmed to be M. fructicola based on morphological characteristics. To our knowledge, this is the first report of occurrence of M. fructicola in Gansu, Yunnan, and Hubei provinces, thousands of kilometers away from eastern China where occurrence of peach brown rot caused by M. fructicola has been confirmed (2,4). The results indicated the further geographical spread of the M. fructicola in China. References: (1) M. J. Hu et al. Plos One 6(9):e24990, 2011. (2) M. J. Hu et al. Plant Dis. 95:225, 2011. (3) T. J. White et al. Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. Academic Press, San Diego, 1990. (4) X. Q. Zhu et al. Plant Pathol. 54:575, 2005.

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