Resistance of transgenic rice events (rbcS:cry1Ac) against three lepidopteran rice pests

The transgenic rice expressing cry1Ac gene, which is linked to the rice rbcS promoter and its transit peptide sequence (tp), was highly resistant against all instars of Cnaphalocrocis medinalis (Guenetée) (Lepidoptera: Crambidae). In this study, we evaluated the larval mortality, behavior change, and field occurrence of three main rice pests, C. medinalis, Naranga aenescens (Moore) (Lepidoptera: Noctuidae), and Parnara guttata (Bremer & Grey) (Lepidoptera: Hesperiidae) in T4 generations of three Bt rice events (rbcS3:cry1Ac; 608102, 608104 and 608107) and non-Bt rice. All of the three Bt rice events were resistant to C. medinalis which showed significantly higher mortality for all instars compared to non-Bt rice. The resistance of Bt rice events against the larvae decreased gradually as the larvae developed. However, the survived larvae which ingested Bt rice events died eventually without further development. The resistance of three Bt rice events was investigated in the pot test, which was conducted with 3rd instars of C. medinalis, N. aenescens, and P. guttata, showed mortalities of over 70%. In behavioral assay, C. medinalis fed on the Bt rice events showed feeding avoidance and less leaf rolling behavior compared to that of the larvae fed on non-Bt rice. A 2-yr field survey conducted with larvae of C. medinalis and P. guttata also showed that the three Bt rice events significantly had lower damaged on leaves compared to that of non-Bt rice. Overall, the three Bt rice events were highly resistant to the larvae of lepidopteran target rice pests.     

Incidence and occurrence profiles of the small brown planthopper (Laodelphax striatellus Fallén) in Korea in 2011–2015

The small brown planthopper (SBPH, Laodelphax striatellus Fallén) is an important pest that causes severe yield losses in rice by transmitting viral plant diseases. For the proper management of this pest, therefore, it is necessary to understand its temporal and spatial dynamics by establishing a periodical monitoring system. A dataset, including the number of SBPHs by location, collection method [aerial collection net (AeCN) or light trap (LT)] and period (May–Aug.) for five years (2011–2015) was provided by the Rural Developmental Administration, and missing values were imputed using multiple imputation methods. Of the 15,848 individuals collected, approximately 47% and 52.9% were collected using the AeCN and LT methods, respectively. Large numbers of SBPHs were generally collected from western coastal regions using AeCNs but not LTs. A high incidence of migratory SBPHs was observed during Julian days 144–166 using the AeCN method, with slightly different migration periods in each year. Generally, the migratory SBPHs made up 39.4% of the total populations of SBPHs during those periods. According to clustering analysis, the migratory region was located along the western coastal regions. Putative migration paths were estimated by trajectory cluster analyses using meteorological data. Interestingly, an L-shaped trajectory path emerged as a potentially important route for migratory SBPHs, passing through major wheat cultivation areas in Henan, Anhui, Jiangsu, and Zhejiang provinces in China, where high densities of SBPHs occur from late May to early June. These results would provide valuable information to predict the incidence period of migratory SBPHs and establish a proactive management system against SBPH, including the basis for the detection of hazardous factors and decisions regarding appropriate pesticide treatment periods.     

Comparing the genetic diversity and structure of indigenous Korean and Chinese populations of Laodelphax striatellus Fallén using mitochondrial haplotypes

The small brown planthopper, Laodelphax striatellus Fallén, is a major migratory pest from China to Korea and transmits viral diseases of rice plants. In this study, we compared the genetic structures of overwintered indigenous Korean and Chinese populations. The eight Korean populations consisted of 33 haplotypes, and 16 of these were newly identified. The genetic diversity of the Korean population revealed high haplotype diversity (Hd) and low nucleotide diversity (π) of 0.86 ± 0.017 and 0.0024 ± 0.0001 on average, respectively. These values for the Chinese population were Hd = 0.92 ± 0.016 and π = 0.0026 ± 0.0002. Overall, genetic distances by pairwise F_ST were generally low, ranging from ? 0.022 to 0.089. Moreover, the Korean population revealed its ongoing population expansion by showing negative values in the neutrality test (Tajima's D = ? 1.4, Fu's Fs = ? 15.8) and a unimodal pattern in the mismatch distribution analysis. The genetic structures and population relationships were determined using 8 indigenous Korean and 30 Chinese populations by Bayesian approaches and population tree construction, respectively. The genetic structure was inferred as five (K = 5), and all indigenous Korean populations as well as 10 Chinese populations from the Shanghai city, Anhui, Henan, Jiangsu, Liaoning, Shandong, and Zhejiang provinces were grouped into ‘G3’. These results provide partial support for unidirectional gene flow by migratory Chinese populations into Korea. Further analysis conducted using specimens from China and Korea collected in similar periods is necessary to clarify the migration population's origin and its effect on the genetic structure of the indigenous populations.     

Suppression of Voltage Decay through Manganese Deactivation and Nickel Redox Buffering in High‐Energy Layered Lithium‐Rich Electrodes

Cobalt‐free layered lithium‐rich nickel manganese oxides, Li[Li_xNi_yMn_1?x?y]O₂ (LLNMO), are promising positive electrode materials for lithium rechargeable batteries because of their high energy density and low materials cost. However, substantial voltage decay is inevitable upon electrochemical cycling, which makes this class of materials less practical. It has been proposed that undesirable voltage decay is linked to irreversible structural rearrangement involving irreversible oxygen loss and cation migration. Herein, the authors demonstrate that the voltage decay of the electrode is correlated to Mn⁴⁺/Mn³⁺ redox activation and subsequent cation disordering, which can be remarkably suppressed via simple compositional tuning to induce the formation of Ni³⁺ in the pristine material. By implementing our new strategy, the Mn⁴⁺/Mn³⁺ reduction is subdued by an alternative redox reaction involving the use of pristine Ni³⁺ as a redox buffer, which has been designed to be widened from Ni³⁺/Ni⁴⁺ to Ni²⁺/Ni⁴⁺, without compensation for the capacity in principle. Negligible change in the voltage profile of modified LLNMO is observed upon extended cycling, and manganese migration into the lithium layer is significantly suppressed. Based on these findings, we propose a general strategy to suppress the voltage decay of Mn‐containing lithium‐rich oxides to achieve long‐lasting high energy density from this class of materials.     

Phage Application for the Protection from Acute Hepatopancreatic Necrosis Disease (AHPND) in <Emphasis Type="Italic">Penaeus vannamei</Emphasis>

Acute hepatopancreatic necrosis disease (AHPND) caused by Vibrio parahaemolyticus has been one of the most problematic diseases in marine shrimp aquaculture throughout Southeast Asia and Latin America. To evaluate the effectiveness of a bacteriophage (phage) treatment for AHPND, a series of bioassays were carried out in a marine shrimp (Penaeus vannamei) model using an AHPND-V. parahaemolyticus strain that is highly pathogenic to shrimp. We monitored the mortality and histopathological changes during phage treatment. Shrimps treated with phage prophylaxis and phage therapy displayed significant protection from AHPND and survived a lethal bacterial challenge.     

The proper localization of RESPONSIVE TO DESICCATION 20 in lipid droplets depends on their biogenesis induced by STRESS-RELATED PROTEINS in vegetative tissues

Arabidopsis LD surface proteins, SRPs are found only in higher plants and are important for LD biogenesis and abiotic stress signaling. However, the cellular mechanism of SRPs is still unclear. To investigate molecular functions of SRPs, we used tobacco transient expression system. Transient expression of SRPs was sufficient and synergistic for LD biogenesis, and SRPs participated in the formation step of LD in tobacco leaves. RESPONSIVE TO DESICCATION 20 (RD20), a known LD-localizing peroxygenase, localized to LD in the presence of an SRP, and its peroxygenase activity correlated with proper localization of RD20 to LD. Our data suggest that Arabidopsis SRPs play roles as positive factors for LD biogenesis to provide a proper localization of LD-localizing proteins in vegetative tissues.