The Internet is believed to bring more technological dividends to vulnerable farmers during the green agriculture transformation.  However, this is different from the theory of skill-biased technological change, which emphasizes that individuals with higher levels of human capital and more technological endowments benefit more.  This study investigates the effects of Internet use on farmers’ adoption of integrated pest management (IPM), theoretically and empirically, based on a dataset containing 1 015 farmers in China’s Shandong Province.  By exploring the perspective of rational inattention, the reasons for the heterogeneity of the effects across farmers with different endowments, i.e., education and land size, are analyzed.  The potential endogeneity issues are addressed using the endogenous switching probit model.  The results reveal that: (1) although Internet use significantly positively affects farmers’ adoption of IPM, vulnerable farmers do not benefit more from it.  Considerable selection bias leads to an overestimation of technological dividends for vulnerable farmers; (2) different sources of technology information lead to the difference in the degree of farmers’ rational inattention toward Internet information, which plays a crucial role in the heterogeneous effect of Internet use; and (3) excessive dependence on strong-tie social network information sources entraps vulnerable farmers in information cocoons, hindering their ability to reap the benefits of Internet use fully.  Therefore, it is essential to promote services geared towards elderly-oriented Internet agricultural technology information and encourage farmers with strong Internet utilization skills to share technology information with other farmers actively.

Soybean mosaic virus (SMV) is one of the major viral pathogens affecting soybean crops worldwide.  Three SMV resistance genes, R_SC4, R_SC8, and R_SC14Q , have been identified and mapped on soybean chromosomes 14, 2, and 13 from Dabaima, Kefeng 1, and Qihuang 1 cultivars, respectively.  Soybean cultivar Nannong 1138-2 is widely grown in the Yangtze River Valley of China.  In this study, crosses were made between Qihuang 1×Kefeng 1 and Dabaima×Nannong 1138-2.  Ten simple sequence repeat (SSR) markers linked to three resistance loci (R_SC4, R_SC8, and R_SC14Q ) were used to assist pyramided breeding.  Pyramided families containing three resistance loci (R_SC4, R_SC8, and R_SC14Q ) were evaluated by inoculating them with 21 SMV strains from China.  Results indicated that the 10 markers can be used effectively to assist the selection of resistant individuals containing R_SC4, R_SC8, and R_SC14Q .  A total of 53 F6 plants were confirmed to contain three homozygous alleles conferring resistance to SMV.  Five F₇ homozygous pyramided families exhibited resistance to 21 strains of SMV and showed desirable agronomic traits using dual selection.  The strategy of pyramiding resistance gene derived from different varieties has practical breeding value in providing broad-spectrum resistance against the existing strains of SMV in China.  

The brown planthopper, Nilaparvata lugens is an economically important pest on rice plants. This species produces macropterous and brachypterous morphs in response to environmental cues, which makes it very difficult to control. The molecular basis of wing patterning in N. lugens is still unknown. It is necessary to identify wing patterning genes of N. lugens, and also to clarify the expression differences of wing patterning genes between macropterous and brachypterous morphs. High-throughput deep sequencing of transcriptome of N. lugens wing pad yielded 116 744 580 raw reads and 113 042 700 clean reads. All the reads were assembled into 55 963 unigenes with an average length of 804 bp. With the E-value cut-off of 1.0E–5,18 359 and 2 883 unigens had hits in NCBI-NR (NCBI non-redundant protein sequences) and NCBI-NT (NCBI nucleotide sequences) databases, respectively. A total of 16 502 unigenes were assigned to GO (gene ontology) classification, 9 709 ungenes were grouped into 26 COG (cluster of orthologous groups of proteins) classifications, and 6 724 unigenes were assigned to different KEGG (Kyoto encyclopedia of genes and genomes) pathways. In total, 56 unigenes which are homologous to wing patterning genes of Drosophila melanogaster or Tribolium castaneum were identified. Out of the 56 unigenes, 24 unigenes were selected, and their expression levels across the five nymphal stages between macropterous strain and brachypterous strain were examined by qRT-PCR. Two-way ANOVA analysis showed that development stage had significant effects on the expression level of all the 24 genes (P<0.05). The expression levels of 8 genes (Nlen, Nlhh, Nlsal, NlAbd-A, Nlwg, Nlvg, Nlexd and NlUbx) were significantly affected by wing morph. This is the first transcriptome analysis of wing pads of hemimetabolous insect, N. lugens. The identified wing patterning genes would be useful resource for future exploration of molecular basis of wing development. The 8 differentially expressed wing patterning genes between macropterous strain and brachypterous strain would contribute to explain molecular mechanism of wing-morph differentiation in N. lugens.

Infectious bursal disease virus (IBDV) is responsible for the highly contagious infectious bursal disease of chickens. Further understanding the gene-function is necessary to design the tailored vaccine. The amino acid residue 279, located on strand PF of VP2, is one of the three residues that have been reported to be involved in cell-tropism but with some inconsistency. In this study, to further clarify the amino acids involved in the cell tropism of IBDV, a series of mutations about residue 279 were introduced into the VP2 of vvIBDV Gx strain. With the reverse genetic system, we found single mutation of D279N, double mutations of D279N/A284T or Q253H/D279N were not enough to adapt IBDV to chicken embryo fibroblast (CEF) cell. To evaluate whether residue 279 could influence the replication and virulence of IBDV, the virus rGxHT-279 with three mutations (Q253H/D279N/A284T) was rescued and evaluated. Results showed that the mutation of residue 279 in VP2 had no efficient effects on both the replication efficiency in vitro and the virulence to SPF chickens of IBDV. In summary, the results demonstrated that residue 279 of VP2 did not contribute efficiently to cell tropism, replication efficiency, and virulence of IBDV at least in some strains. These findings provided further information for understanding the gene function of IBDV.

Food safety issues constitute an international topic discussed by many scholars. Although there is an extensive body of literature on comparisons of food safety control practices across different governance structures, these studies have been conducted mainly in terms of qualitative and descriptive analysis. In addition, little attention has been given to family farms. This study addresses the food safety control practices adopted by firms with different governance structures in China. Food safety control is expressed by the following aspects, i.e., pollution-free, green, organic, and/or geographical indication products certification, establishment of production records, and pesticide residue testing. Three types of governance structures that engage in agricultural production are distinguished: farmer cooperatives, agricultural companies, and family farms. The food safety control practices of various governance structures are investigated based on a database that comprises 600 vegetable and fruit enterprises in Zhejiang, China. The results show that (1) pesticide residue testing is adopted by the most firms, followed by products certification, and production records are adopted by the fewest firms, and (2) agricultural companies adopt more food safety control practices than family farms, while farmer cooperatives adopt the fewest food safety control practices. Governance structure features of a cooperative in terms of ownership, decision-making, and income distribution are the main reasons for the low level of food safety control in the cooperative.

Soybean mosaic virus (SMV), a member of the genus Potyvirus, is a major pathogen of soybean plants in China, and 16 SMV strains have been identified nationwide based on a former detailed SMV classification system. As the P3 gene is thought to be involved in viral replication, systemic infection, pathogenicity, and overcoming resistance, knowledge of the P3 gene sequences of SMV and other potyviruses would be useful in efforts to know the genetic relationships among them and control the disease. P3 gene sequences were obtained from representative isolates of the above-mentioned 16 SMV strains and were compared with other SMV strains and 16 Potyvirus species from the National Center for Biotechnology GenBank database. The P3 genes from the 16 SMV isolates are composed of 1 041 nucleotides, encoding 347 amino acids, and share 90.7-100% nucleotide (NT) sequence identities and 95.1-100% amino acid (AA) sequence identities. The P3 coding regions of the 16 SMV isolates share high identities (92.4-98.9% NT and 96.0-100% AA) with the reported Korean isolates, followed by the USA isolates (88.5-97.9% NT and 91.4-98.6% AA), and share low identities (80.5-85.2% NT and 82.1-84.7% AA) with the reported HZ1 and P isolates from Pinellia ternata. The sequence identities of the P3 genes between SMV and the 16 potyviruses varied from 44.4 to 81.9% in the NT sequences and from 21.4 to 85.3% in the AA sequences, respectively. Among them, SMV was closely related to Watermelon mosaic virus (WMV), with 76.0-81.9% NT and 77.5-85.3% AA identities. In addition, the SMV isolates and potyvirus species were clustered into six distinct groups. All the SMV strains isolated from soybean were clustered in Group I, and the remaining species were clustered in other groups. A multiple sequence alignment analysis of the C-terminal regions indicated that the P3 genes within a species were highly conserved, whereas those among species were relatively variable.