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β-glucosidase is a key enzyme in the degradation of lignocellulosic biomass, which is responsible for the conversion of oligosaccharides from cellulose hydrolysates to glucose. However, its required high temperatures and the presence of inhibitors have limited its use in industry. In this study, a new β-glucosidase gene, named thbg2, was obtained from the metagenome Ruidian Hot Spring, Tengchong City, Yunnan Province, southwestern China. The gene was synthesized, cloned, heterologously expressed, and enzymatically characterized. Its optimum temperature and pH were 60 °C and pH 5.6, respectively. ThBg2 exhibited more than 60% relative activity in temperatures ranging from 40 °C to 70 °C and across a pH of 4.0–6.6. It maintained 100% relative activity after incubation at either 50 °C for 24 h or 60 °C for 12 h and more than 80% residual activity after incubation at pH 4.0–6.0 for 24 h. Moreover, it maintained more than 80% relative activity in the presence of heavy metal ions, ethanol, SDS etc. Furthermore, glucose yields from corn stalks increased by 20% after ThBg2 (0.05 mg/mL) was added to the commercial cellulase reaction system. Overall, this work identified a thermophilic and inhibitor-tolerant β-glucosidase with potential applications in commercial lignocellulose utilization and the bioenergy industry. [ABSTRACT FROM AUTHOR]

[Objectives] The study was to confirm the etiological agent of leaf spot on banana in Yunnan Province of China. [Methods] Fungus isolates were isolated from the diseased tissues, and cultured to observe the morphological characteristics of colony and spore. Furthermore, phylogenetic analyses and pathogenicity test were also conducted to confirm the pathogen. [Results] The fungus isolated from the diseased tissues was identified as Neopestalotiopsis clavispora. [Conclusions] N. clavispora is a new pathogen causing leaf spot of banana. This research provides the first description of N. clavispora as a causal agent on banana in China, and adds new insights related to the host range of N. clavispora. [ABSTRACT FROM AUTHOR]

The information collected through multi-environment testing of wheat genotypes not only provides basis to identify promising genotypes but also to ascertain their yield potential and the genetic gains. For this purpose, in the presented study, the data originated from the Yunnan provincial Regional Yield Trials (RYT) conducted during 2006 and 2018 was used. During this period, 107 genotypes were evaluated at 18 locations under Upland Wheat (UW) management scheme, while 116 genotypes were evaluated at 21 locations under Field Wheat (FW) management scheme. By adopting standard statistical approaches and through repeated elimination procedures, 7 genotypes emerged as promising for UW and 11 for FW cultivation. These genotypes have genetic variance >1 and 44/33% higher average yield than that of UW/FW genotypes. Most of these promising genotypes were tested during 2016 and 2018 cropping seasons. This indicated a good genetic gain of around 0.7 t/ha in recent years from that of base year. These genotypes, however, needs to be further evaluated in diverse environments suitable for spring type wheat cultivation to ascertain the extent of their interaction with wider environmental conditions and possibility of using in local breeding programs of those target environments. [ABSTRACT FROM AUTHOR]

Introduction: Since the late 1970's, time-space clusters of sudden unexplained death (SUD) in northwest Yunnan, China have alarmed the public and health authorities. From 2006-2009, we initiated enhanced surveillance for SUD to identify a cause, and we warned villagers to avoid eating unfamiliar mushrooms. Methods: We established surveillance for SUD, defined as follows: sudden onset of serious, unexplained physical impairment followed by death in <24 hours. A mild case was onset of any illness in a member of the family or close socially related group of a SUD victim within 1 week of a SUD. We interviewed witnesses of SUD and mild case-persons to identify exposures to potentially toxic substances. We tested blood from mild cases, villagers, and for standard biochemical, enzyme, and electrolyte markers of disease. Results: We identified 33 SUD, a 73% decline from 2002-2005, distributed among 21 villages of 11 counties. We found a previously undescribed mushroom, Trogia venenata, was eaten by 5 of 7 families with SUD clusters compared to 0 of 31 other control-families from the same villages. In T. venenata-exposed persons SUD was characterized by sudden loss of consciousness during normal activities. This mushroom grew nearby 75% of 61 villages that had time-space SUD clusters from 1975 to 2009 compared to 17% of 18 villages with only single SUD (p<0.001, Fisher's exact test). Discussion: Epidemiologic data has implicated T. venenata as a probable cause of clusters of SUD in northwestern Yunnan Province. Warnings to villagers about eating this mushroom should continue. [ABSTRACT FROM AUTHOR]