Hylocereus undatus widely grows in southern China. Some varieties are planted for their fruits, known as dragon fruits or Pitaya, while some varieties for their flowers known as Bawanghua. Fresh or dried flowers of Bawanghua are used as routine Chinese medicinal food. Since 2008, a serious anthracnose disease has led to great losses on Bawanghua flower production farms in the Baiyun district of Guangzhou city in China. Anthracnose symptoms on young stems of Bawanghua are reddish-brown, sunken lesions with pink masses of spores in the center. The lesions expand rapidly in the field or in storage, and may coalesce in the warm and wet environment in spring and summer in Guangzhou. Fewer flowers develop on infected stems than on healthy ones. The fungus overwinters in infected debris in the soil. The disease caused a loss of up to 50% on Bawanghua. Putative pathogenic fungi with whitish-orange colonies were isolated from a small piece of tissue (3 × 3 mm) cut from a lesion margin and cultured on potato dextrose agar in a growth chamber at 25°C, 80% RH. Dark colonies with acervuli bearing pinkish conidial masses formed 14 days later. Single celled conidia were 11 to 18 × 4 to 6 μm. Based on these morphological characteristics, the fungi were identified as Colletotrichum gloeosporioides (Penz.) Penz. & Sacc (2). To confirm this, DNA was extracted from isolate BWH1 and multilocus analyses were completed with DNA sequence data generated from partial ITS region of nrDNA, actin (ACT) and glutamine synthetase (GS) nucleotide sequences by PCR, with C. gloeosporioides specific primers as ITS4 (5'-TCCTCCGCTTATTGATATGC-3') / CgInt (5'-GGCCTCCCGCCTCCGGGCGG-3'), GS-F (5'-ATGGCCGAGTACATCTGG-3') / GS-R (5'-GAACCGTCGAAGTTCCAC-3') and actin-R (5'-ATGTGCAAGGCCGGTTTCGC-3') / actin-F (5'-TACGAGTCCTTCTGGCCCAT-3'). The sequence alignment results indicated that the obtained partial ITS sequence of 468 bp (GenBank Accession No. KF051997), actin sequence of 282 bp (KF712382), and GS sequence of 1,021 bp (KF719176) are 99%, 96%, and 95% identical to JQ676185.1 for partial ITS, FJ907430 for ACT, and FJ972589 for GS of C. gloeosporioides previously deposited, respectively. For testing its pathogenicity, 20 μl of conidia suspension (1 × 106 conidia/ml) using sterile distilled water (SDW) was inoculated into artificial wounds on six healthy young stems of Bawanghua using sterile fine-syringe needle. Meanwhile, 20 μl of SDW was inoculated on six healthy stems as a control. The inoculated stems were kept at 25°C, about 90% relative humidity. Three independent experiments were carried out. Reddish-brown lesions formed after 10 days, on 100% stems (18 in total) inoculated by C. gloeosporioides, while no lesion formed on any control. The pathogen was successfully re-isolated from the inoculated stem lesions on Bawanghua. Thus, Koch's postulates were fulfilled. Colletotrichum anthracnose has been reported on Pitaya in Japan (3), Malaysia (1) and in Brazil (4). To our knowledge, this is the first report of anthracnose disease caused by C. gloeosporioides on young stems of Bawanghua (H. undatus) in China. References: (1) M. Masyahit et al. Am. J. Appl. Sci. 6:902, 2009. (2) B. C. Sutton. Page 402 in: Colletotrichum Biology, Pathology and Control. J. A. Bailey and M. J. Jeger, eds. CAB International, Wallingford, UK, 1992. (3) S. Taba et al. Jpn. J. Phytopathol. 72:25, 2006. (4) L. M. Takahashi et al. Australas. Plant Dis. Notes 3:96, 2008.
Dengue is a rapidly spreading mosquito-borne disease caused by the dengue virus (DENV) and has emerged as a severe public health problem around the world. Guangdong, one of the southern Chinese provinces, experienced a serious outbreak of dengue in 2014, which was believed to be the worst dengue epidemic in China over the last 20 years. To better understand the epidemic, we collected the epidemiological data of the outbreak and analyzed 14,594 clinically suspected dengue patients from 25 hospitals in Guangdong. Dengue cases were then laboratory-confirmed by the detection of DENV non-structural protein 1 (NS1) antigen and/or DENV RNA. Afterwards, clinical manifestations of dengue patients were analyzed and 93 laboratory-positive serum specimens were chosen for the DENV serotyping and molecular analysis. Our data showed that the 2014 dengue outbreak in Guangdong had spread to 20 cities and more than 45 thousand people suffered from dengue fever. Of 14,594 participants, 11,387 were definitively diagnosed. Most manifested with a typical non-severe clinical course, and 1.96 % developed to severe dengue. The strains isolated successfully from the serum samples were identified as DENV-1. Genetic analyses revealed that the strains were classified into genotypes I and V of DENV-1, and the dengue epidemic of Guangdong in 2014 was caused by indigenous cases and imported cases from the neighboring Southeast Asian countries of Malaysia and Singapore. Overall, our study is informative and significant to the 2014 dengue outbreak in Guangdong and will provide crucial implications for dengue prevention and control in China and elsewhere.
In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.