Hybrid wild boar husbandry is an important component of livestock production in Northeast China.  However, the current disease situation of these animals is largely unknown due to a lack of disease surveillance.  The present study was conducted to determine the prevalence of several important viral diseases in the hybrid wild boar population of Northeast China.  Between September 2015 to December 2016, 169 blood and 61 tissue samples were collected from apparently healthy hybrid wild boars from farms in Jilin, Inner Mongolia and Heilongjiang provinces.  ELISA detected serum antibodies against classical swine fever virus (CSFV), porcine reproductive and respiratory syndrome virus (PRRSV), pseudorabies virus (PRV), porcine circovirus type 2 (PCV2) and Japanese encephalitis virus (JEV), but not against African swine fever virus (ASFV), with PCV2 having the highest seropositive rate (87.2–100% in different farms).  RT-PCR or PCR performed on the processed samples detected only PCV2, with 33.1% (56/169) of blood samples and 32.8% (20/61) of spleen samples being positive, respectively, indicating widespread PCV2 infection in hybrid wild boars.  Phylogenetic analysis of 15 PCV2 ORF2 sequences showed that they belong to genotypes PCV2a, PCV2b and PCV2d, with nucleotide and deduced amino acid homologies of 88.5–100% and 88.1–100%, respectively. 

The growth and yield of peanut are negatively affected by continuous cropping.  Arbuscular mycorrhizal fungi (AMF) and calcium ions (Ca²⁺) have been used to improve stress resistance in other plants, but little is known about their roles in peanut seedling growth under continuous cropping.  This study investigated the possible roles of the AMF Glomus mosseae combined with exogenous Ca²⁺ in improving the physiological responses of peanut seedlings under continuous cropping.  G. mosseae combined with exogenous Ca²⁺ can enhance plant biomass, Ca²⁺ level, and total chlorophyll content.  Under exogenous Ca²⁺ application, the F_v/F_m in arbuscular mycorrhizal (AM) plant leaves was higher than that in the control plants when they were exposed to high irradiance levels.  The peroxidase, superoxide dismutase, and catalase activities in AM plant leaves also reached their maximums, and accordingly, the malondialdehyde content was the lowest compared to other treatments.  Additionally, root activity, and content of total phenolics and flavonoids were significantly increased in AM plant roots treated by Ca²⁺ compared to either G. mosseae inoculation or Ca²⁺ treatment alone.  Transcription levels of AhCaM, AhCDPK, AhRAM1, and AhRAM2 were significantly improved in AM plant roots under exogenous Ca²⁺ treatment.  This implied that exogenous Ca²⁺ might be involved in the regulation of G. mosseae colonization of peanut plants, and in turn, AM symbiosis might activate the Ca²⁺ signal transduction pathway.  The combination of AMF and Ca²⁺ benefitted plant growth and development under continuous cropping, suggesting that it is a promising method to cope with the stress caused by continuous cropping.

Abiotic stresses, especially drought and salt, severely affect maize production, which is one of the most important cereal crops in the world.  Breeding stress-tolerant maize through biotechnology is urgently needed to maintain maize production.  Therefore, it is important to identify new genes that can enhance both drought and salt stress tolerance for molecular breeding. In this study, we identified a maize ABA (abscisic acid)-responsive element (ABRE) binding protein from a 17-day post-pollination (dpp) maize embryo cDNA library by yeast one-hybrid screen using the ABRE2 sequence of the maize Cat1 gene as bait.  This protein, designated, ABRE binding protein 2 (ABP2), belongs to the bZIP transcription factor family.  Endogenous expression of ABP2 in maize can be detected in different tissues at various development stages, and can be induced by drought, salt, reactive oxygen species (ROS)-generating agents, and ABA treatment.  Constitutive expression of ABP2 in transgenic Arabidopsis plants enhanced tolerance to drought and salt stress, and increased sensitivity to ABA.  In exploring the mechanism by which ABP2 can stimulate abiotic stress tolerance, we found that ROS levels were reduced and expression of stress-responsive and carbon metabolism-related genes was enhanced by constitutive ABP2 expression in transgenic plants.  In short, we identified a maize bZIP transcription factor which can enhance both drought and salt tolerance of plants.