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The current study intended to have a brief understanding-based analysis of the Chinese university students' understanding of the traditional Chinese classroom teaching method and the PAD classroom teaching method to investigate the feasibility and efficiency of the two teaching methods in the Chinese university students' "College English" classes. Through applying a quantitative research design using the descriptive approach, questionnaires were distributed to thirty Chinese university students. The current study had revealed that the PAD classroom teaching method was much more favorable than the traditional Chinese classroom teaching method by most of the Chinese university students in their "College English" classes. Thus, the implication of the current study was that the PAD classroom teaching method was strongly suggested to be given more opportunities to be applied and practiced by the teachers in the Chinese university students' "College English" classes.

This paper aims to further understand the future development of literacy theory and language learning in contemporary Chinese universities through the research on the current situation of EFL students' literacy in Chinese universities and the teaching characteristics of contemporary Chinese teachers. In this study, literature analysis method, literature comparison analysis method, literature synthesis method and other analytical methods were used to obtain the results. Based on our results, the lack of literacy training is an extremely important reason for the defects of literacy skills of contemporary Chinese college EFL students in the process of language learning. The strengthening of literacy training is one of the key measures to improve the comprehensive level of literacy of contemporary Chinese college EFL students in the process of their language learning. Theoretically, the future development of literacy theories and language learning among contemporary Chinese college EFL students is bound to closely connect with the new theory of multiliteracies and critical literacy in literacy development and the multiliteracies teaching methodology in language learning. Practically, the new theory of multiliteracies puts forward a series of hypotheses for school literacy education to cope with the drastic changes facing the world today. At the same time, the critical literacy theory is rooted in critical education theory, focusing on the important role of literacy in the formation of individual human values. Besides, the multiliteracies teaching methodology in language learning explores how to change traditional teaching methods, effectively using multimedia resources, and cultivating language learners' skills of multiliteracies.

Abstract Background Huanglongbing (HLB) is a highly destructive disease of citrus production worldwide. 'Candidatus Liberibacter asiaticus', an unculturable alpha proteobacterium, is a putative pathogen of HLB. Information about the biology and strain diversity of 'Ca. L. asiaticus' is currently limited, inhibiting the scope of HLB research and control. Results A genomic region (CLIBASIA_05640 to CLIBASIA_05650) of 'Ca. L. asiaticus' showing hyper-sequence variation or locus mosaicism was identified and investigated using 262 bacterial strains (188 from China and 74 from Florida). Based on the characteristic electrophoretic profiles of PCR amplicons generated by a specific primer set, eight electrophoretic types (E-types) were identified, six E-types (A, B, C, D, E, and F) in China and four E-types (A, C, G, and H) in Florida. The 'Ca. L. asiaticus' strains from China consisted predominately of E-type A (71.3%) and E-type B (19.7%). In contrast, the 'Ca. L. asiaticus' strains from Florida was predominated by E-type G (82.4%). Diversity of 'Ca. L. asiaticus' in China was also evidenced. Strains from the high altitude Yunnan Province consisted of five E-types with E-type B being the majority (62.8%), whereas strains from the low altitude coastal Guangdong Province consisted of only two E-types with E-type A as the majority (97.0%). Sequence analyses revealed that variation of DNA amplicons was due to insertion/deletion events at CLIBASIA_05650 and the downstream intergenic region. Conclusions This study demonstrated the genomic mosaicism of 'Ca. L. asiaticus' resulted from active DNA insertion/deletion activities. Analyses of strain variation depicted the significant inter- and intra-continent diversity of 'Ca. L. asiaticus'.

Summary: Legumes form a symbiosis with atmospheric nitrogen (N2)‐fixing soil rhizobia, resulting in new root organs called nodules that enable N2‐fixation. Nodulation is a costly process that is tightly regulated by the host through autoregulation of nodulation (AON) and nitrate‐dependent regulation of nodulation. Both pathways require legume‐specific CLAVATA/ESR‐related (CLE) peptides.Nitrogen‐induced nodulation‐suppressing CLE peptides have not previously been investigated in Medicago truncatula, for which only rhizobia‐induced MtCLE12 and MtCLE13 have been characterised. Here, we report on novel peptides MtCLE34 and MtCLE35 in nodulation control.The nodulation‐suppressing CLE peptides of five legume species were classified into three clades based on sequence homology and phylogeny. This approached identified MtCLE34 and MtCLE35 and four new CLE peptide orthologues of Pisum sativum. Whereas MtCLE12 and MtCLE13 are induced by rhizobia, MtCLE34 and MtCLE35 respond to both rhizobia and nitrate. MtCLE34 was identified as a pseudogene lacking a functional CLE‐domain. MtCLE35 was found to inhibit nodulation in a SUNN‐ and RDN1‐dependent manner via overexpression analysis.Together, our findings indicate that MtCLE12 and MtCLE13 have a specific role in AON, while MtCLE35 regulates nodule numbers in response to both rhizobia and nitrate. MtCLE34 likely had a similar role to MtCLE35, but its function was lost due to a premature nonsense mutation. [ABSTRACT FROM AUTHOR]

BACKGROUND Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, is an important pest of citrus worldwide because it transmits the bacteria causing huanglongbing (HLB). We investigated the effects and persistence of two soil application rates of thiamethoxam on ACP populations in two flushing seasons in the field. Thiamethoxam and clothianidin residues in the fruit were detected to evaluate food safety. RESULTS: Soil application of 50% thiamethoxam water‐dispersible granules at concentrations of 4 and 10 g tree−1 significantly decreased ACP populations, and there was a positive correlation between control efficacy and the persistence of thiamethoxam and clothianidin in leaves, providing longer‐term protection for up to 90 days in the fall compared with 60 days in the spring. Higher thiamethoxam and clothianidin amounts were observed in new leaves than in old leaves. Thiamethoxam and clothianidin residues at a high rate in fruit were 0.012 and 0.010 mg kg−1 at harvest, respectively, and neither insecticides was detectable at low rates. CONCLUSIONS: These results demonstrate that soil‐applied thiamethoxam plays a role in defending ACP, and provides an extended period of control efficacy. This knowledge could provide a reference for the control of ACP by soil application of thiamethoxam to reduce HLB spread. © 2018 Society of Chemical Industry Soil application of thiamethoxam provided an extended period of efficacy to Asian citrus psyllid. Thiamethoxam and clothianidin residues in fruits were below the maximum residue limit in Japan. [ABSTRACT FROM AUTHOR]

Global demand to increase food production and simultaneously reduce synthetic nitrogen fertilizer inputs in agriculture are underpinning the need to intensify the use of legume crops. The symbiotic relationship that legume plants establish with nitrogen‐fixing rhizobia bacteria is central to their advantage. This plant–microbe interaction results in newly developed root organs, called nodules, where the rhizobia convert atmospheric nitrogen gas into forms of nitrogen the plant can use. However, the process of developing and maintaining nodules is resource intensive; hence, the plant tightly controls the number of nodules forming. A variety of molecular mechanisms are used to regulate nodule numbers under both favourable and stressful growing conditions, enabling the plant to conserve resources and optimize development in response to a range of circumstances. Using genetic and genomic approaches, many components acting in the regulation of nodulation have now been identified. Discovering and functionally characterizing these components can provide genetic targets and polymorphic markers that aid in the selection of superior legume cultivars and rhizobia strains that benefit agricultural sustainability and food security. This review addresses recent findings in nodulation control, presents detailed models of the molecular mechanisms driving these processes, and identifies gaps in these processes that are not yet fully explained. Legumes form a beneficial symbiosis with soil bacteria, known as rhizobia, which is signified by the production of nodules on the host plant's roots. The host plant prevents over colonization by rhizobia through various molecular mechanisms that tightly control nodule numbers in response to biotic and abiotic factors. Components of these pathways are key to understanding and optimizing nodulation processes and are the focus of this review. [ABSTRACT FROM AUTHOR]

The prophage/phage region in the genome of 'Candidatus Liberibacter asiaticus', an alpha-proteobacterium associated with citrus Huanglongbing, included many valuable loci for genetic diversity studies. Previously, a mosaic genomic region (CLIBASIA_05640 to CLIBASIA_05650) was characterized, and this revealed inter- and intracontinental variations of 'Ca. L. asiaticus'. In this study, 267 'Ca. L. asiaticus' isolates collected from eight provinces in China were analysed with a primer set flanking the same mosaic region plus downstream sequence. While most amplicon sizes ranged from 1400 to 2000 bp, an amplicon of 550 bp (S550) was found in 14 samples collected from south-western China. Sequence analyses showed that S550 was the result of a 1033 bp deletion which included the previously known mosaic region. The genetic nature of the deletion event remains unknown. The regional restriction of S550 suggests that the 'Ca. L. asiaticus' population from south-western China is different from those in eastern China. The small and easy-to-detect S550 amplicon could serve as a molecular marker for 'Ca. L. asiaticus' epidemiology. [ABSTRACT FROM AUTHOR]