The yield of winter wheat is hindered by drought and low temperature in the Loess Plateau of China.  Two common mulching methods to conserve soil moisture, ridge furrows with plastic film mulching (RP) and flat soil surfaces with plastic film mulching (FP) are helpful for wheat production.  Our previous study indicated that FP could improve wheat yield more effectively than RP, but the reason remains unclear.  The effect of mulching method on functional bacteria also needs to be further studied.  In this study, winter wheat was employed to evaluate the impacts of mulching method on soil temperature, moisture content, microorganisms and grain yield.  The results showed that FP had a warming effect when the soil temperature was low and a cooling effect when the temperature was too high.  However, the ability to regulate soil temperature in the RP method was unstable and varied with year.  The lowest negative accumulated soil temperature was found in the FP treatment, which was 20–89 and 43–99% lower than that of the RP and flat sowing with non-film mulching control (NP) treatments, respectively.  Deep soil moisture was better transferred to topsoil for wheat growth in the FP and RP treatments than the NP treatment, which made the topsoil moisture in the two treatments (especially FP) more sufficient than that in the NP treatment during the early growing stage of wheat.  However, due to the limited water resources in the study area, there was almost no difference between treatments in topsoil water storage during the later stage.  The wheat yield in the FP treatment was significantly higher, by 12–16 and 23–56%, respectively, than in the RP and NP treatments.  Significant positive correlations were observed among the negative accumulated soil temperature, spike number and wheat yield.  The Chao1 and Shannon indices in the RP treatment were 17 and 3.9% higher than those in the NP treatment, respectively.  However, according to network relationship analysis, the interspecific relationships of bacteria were weakened in the RP treatment.  Phosphorus solubilizing, ammonification and nitrification bacteria were more active in the RP than in the FP treatment, and microbes with nitrate reduction ability and plant pathogens were inhibited in the RP treatment, which improved nutrient availability and habitat for wheat.

Osteoblasts are considered as a major factor contributing to bone development and mineralization, however, few studies have been done to establish and evaluate the primary cultured tibial osteoblast model of broiler chicks.  Therefore, in the present study, two experiments were conducted to establish and evaluate the primary cultured tibial osteoblast model of broiler chicks.  In experiment 1, osteoblasts were isolated from the tibia of one-day-old Arbor Acre male broiler chicks using the explant method and identified through the cell morphology, alkaline phosphatase (ALP) and alizarin red staining.  Experiment 2 was carried out to evaluate the vitality and mineralization of primary cultured tibial osteoblasts of broilers on days 4, 8, 12, 16, 20, 24, 28 and 32 after incubation, respectively.  The results from experiment 1 demonstrated that primary cultured tibial osteoblasts of broilers showed a spindle-shaped, triangular or polygonal morphology.  More than 95% of the cells were stained blue-black after ALP staining, and mineralized nodules were formed after 4 days of continuous incubation.  in experiment 2, lactate dehydrogenase (LDH) activity stayed at a relatively stabilized level although incubation time affected (P=0.0012) it during the whole culture period.  Additionally, incubation time affected (P≤0.0001) the number and proportion of the area of mineralized nodules.  They increased linearly and quadratically (P<0.04) with the increase of incubation time, and remained at a stabilized level from 24 to 32 days of incubation.  The estimates of the optimal incubation time were 17 and 26 days based on the best fitted broken-line or quadratic models (P<0.0001) of the number and proportion of the area of mineralized nodules, respectively.  These results indicate that the primary cultured tibial osteoblast model of broilers has been established successfully by the explant method, and it showed typical osteoblast morphology and characteristics of ALP activity and mineralization, and could maintain a relatively stabilized vitality from 4 to 32 days of incubation; and the optimal incubation time of primary tibial osteoblasts was 17 to 26 days.  Therefore, it could be used to further study the underlying mechanisms of bone development and mineralization of broiler chicks.

The aim of the study was to investigate whether phosphorus (P) transporters, type IIb sodium-dependent phosphate cotransporter (NaP-IIb) and inorganic phosphate transporter 2 (PiT2), were directly involved in P absorption across primary cultured duodenal epithelial cell monolayers of chick embryos.  The siRNAs against NaP-IIb or PiT2 were designed, synthesized and transfected into primary cultured duodenal epithelial cells of chick embryos.  Then, the inhibitory efficiency of siRNAs against NaP-IIb or PiT2 was analyzed, and the most efficacious siRNAs were selected to be used for subsequent P absorption experiments.  Briefly, primary cultured duodenal epithelial cells of chick embryos were transfected with either NaP-IIb or PiT2 siRNAs and grown in confluent monolayers on transwell plates.  The untransfected or transfected cell monolayers were then incubated in an uptake medium containing 0 or 0.25 mmol L^–1 of P as KH₂PO₄ to measure the P absorption across duodenal epithelial cell monolayers.  The results showed that among the siRNAs designed, si-1372 and si-890 were demonstrated to be the most effective in inhibiting the NaP-IIb and PiT2 expressions, respectively.  Supplemental P increased (P=0.065) the protein abundance of PiT2 and enhanced (P<0.0001) P absorption in primary cultured duodenal epithelial cell of chick embryos.  Furthermore, NaP-IIb silencing decreased (P=0.07) P absorption across duodenal epithelial cell monolayers, while PiT2 silencing had no effect (P=0.345).  It is concluded that the NaP-IIb, but not PiT2, might be directly involved in the P absorption of chick duodenal epithelial cells.

The bone morphogenetic protein (BMP) and mitogen-activated protein kinase (MAPK) signaling pathways play an important role in regulation of bone formation and development, however, it remains unclear that the effect of dietary different levels of non-phytate phosphorus (NPP) on these signaling pathways and their correlations with bone phosphorus (P) retention and bone development in broilers.  Therefore, this experiment was conducted to investigate the effect of dietary P supplementation on BMP and MAPK signaling pathways and their correlations with bone P retention and bone development in broilers.  A total of 800 one-day-old Arbor Acres male broilers were randomly allotted to 1 of 5 treatments with 8 replicates in a completely randomized design.  The 5 treatments of dietary NPP levels were 0.15, 0.25, 0.35, 0.45 and 0.55% or 0.15, 0.22, 0.29, 0.36 and 0.43% for broilers from 1 to 21 days of age or 22 to 42 days of age, respectively.  The results showed that extracellular signal-regulated kinase 1 (ERK1) mRNA expression in the tibia of broilers on days 14 and 28, phosphorylated-ERK1 (p-ERK1) on day 14, and BMP2 protein expression on days 28 and 42 decreased linearly (P<0.04), while c-Jun N-terminal kinase 1 (JNK1) mRNA expression on day 42 increased linearly (P<0.02) with the increase of dietary NPP level.  At 14 days of age, total P accumulation in tibia ash (TP_TA), bone mineral concentration (BMC), bone mineral density (BMD), bone breaking strength (BBS) and tibia ash were negatively correlated (r=–0.726 to –0.359, P<0.05) with ERK1 and JNK1 mRNA as well as p-ERK1; tibia alkaline phosphatase (ALP) and bone gal protein (BGP) were positively correlated (r=0.405 to 0.665, P<0.01) with ERK1 mRNA and p-ERK1.  At 28 days of age, TP_TA, BMC, BMD, BBS and tibia ash were negatively correlated (r=–0.518 to –0.370, P<0.05) with ERK1 mRNA and BMP2 protein, while tibia ALP was positively correlated (r=0.382 to 0.648, P<0.05) with them.  The results indicated that TP_TA, BMC, BMD, BBS or tibia ash had negative correlations, while tibia ALP and BGP had positive correlations with ERK1 and JNK1 mRNAs, BMP2 protein and p-ERK1, suggesting that bone P retention and bone development might be regulated by BMP and MAPK signaling pathways in broiler chickens.

The loss of N in farmland is an important cause of agricultural non-point source pollution, which seriously impacts the aquatic environment.  A two-year (2017–2018) experiment was conducted to investigate the characteristics of runoff and N losses under different tillage practices.  Taking downslope ridge planting and cross ridge planting as the experimental treatments, the characteristics of surface runoff, interflow, and N losses in sloping farmlands with yellow soil were studied throughout the maize growth period.  As the rainfall increased, the surface runoff and interflow also increased.  The surface runoff and N losses in the surface runoff of downslope ridge planting were significantly higher than those of cross ridge planting.  The interflow volumes and N losses in the 0–20 and 20–40 cm soil layers of the cross ridge planting were significantly higher than those of the downslope ridge planting.  The total N (TN) losses from surface runoff accounted for 54.95–81.25% of the N losses from all pathways.  Therefore, we inferred that surface runoff is the main pathway of N losses.  Dissolved total N (DTN) was the main form of N loss under different tillage measures, as it accounted for 55.82–94.41% of the TN losses, and dissolved organic N accounted for 52.81–87.06% of the DTN losses.  Thus, we inferred that dissolved N is the main form of N loss.  Future research must focus on the prevention and control of the N losses during the maize seedling stage to reduce the environmental pollution caused by ammonium N through runoff.

Organic phosphorus (P) is an important component of the soil P pool, and it has been proven to be a potential source of P for plants.  The phosphorus utilization efficiency (PUE) and PUE related traits (tiller number (TN), shoot dry weight (DW), and root dry weight) under different phytate-P conditions (low phytate-P, 0.05 mmol L^–1 and normal phytate-P, 0.5 mmol L^–1) were investigated using a population consisting of 128 recombinant inbred lines (RILs) at the vegetative stage in barley.  The population was derived from a cross between a P-inefficient genotype (Baudin) and a P-efficient genotype (CN4027, a Hordeum spontaneum accession).  A major locus (designated Qpue.sau-3H) conferring PUE was detected in shoots and roots from the RIL population.  The quantitative trait locus (QTL) was mapped on chromosome 3H and the allele from CN4027 confers high PUE.  This locus explained up to 30.3 and 28.4% of the phenotypic variance in shoots under low and normal phytate-P conditions, respectively.  It also explains 28.3 and 30.7% of the phenotypic variation in root under the low and normal phytate-P conditions, respectively.  Results from this study also showed that TN was not correlated with PUE, and a QTL controlling TN was detected on chromosome 5H.  However, dry weight (DW) was significantly and positively correlated with PUE, and a QTL controlling DW was detected near the Qpue.sau-3H locus.  Based on a covariance analysis, existing data indicated that, although DW may affect PUE, different genes at this locus are likely involved in controlling these two traits.

Maize genotypes vary significantly in their nitrogen use efficiencies (NUEs).  Better understanding of early grain filling characteristics of maize is important, especially for maize with different NUEs.  The objectives of this research were (i) to investigate the difference in apical kernel development of maize with different NUEs, (ii) to determine the reaction of apical kernel development to N application levels, and (iii) to evaluate the relationship between apical kernel development and grain yield (GY) for different genotypes of maize.  Three maize hybrid varieties with different NUEs were cultivated in a field with different levels of N fertilizer arranged during two growing seasons.  Kernel fresh weight (KFW), volume (KV) and dry weight (KDW) of apical kernel were evaluated at an early grain filling stage.  Ear characteristics, GY and its components were determined at maturity stage.  Apical kernel of the high N and high efficiency (HN-HE) type (under low N, the yield is lower, and under higher N, the yield is higher) developed better under high N (N210 and N240, pure N of 210 and 240 kg ha^–1) than at low N (N120 and N140, pure N of 120 and 140 kg ha^–1).  The low N and high efficiency (LN-HE) type (under low N, the yield is higher, while under higher N, the yield is not significantly higher) developed better under low N than at high N.  The double high efficiency (D-HE) type (for both low and high N, the yield is higher) performed well under both high and low N.  Apical kernel reacted differently to the N supply.  Apical kernel developed well at an early grain filling stage and resulted in a higher kernel number (KN), kernel weight (KW) and GY with better ear characteristics at maturity.

Cuticular wax plays an important role in protecting land plant against biotic and abiotic stresses.  Cuticular wax production on plant surface is often visualized by a characteristic glaucous appearance.  This study identified quantitative trait loci (QTLs) for wheat (Triticum aestivum L.) flag leaf glaucousness (FLG) using a high-density genetic linkage map developed from a recombinant inbred line (RIL) population derived from the cross Heyne×Lakin by single-seed descent.  The map consisted of 2 068 single nucleotide polymorphism (SNP) markers and 157 simple sequence repeat (SSR) markers on all 21 wheat chromosomes and covered a genetic distance of 2 381.19 cM, with an average marker interval of 1.07 cM. Two additive QTLs for FLG were identified on chromosomes 3AL and 2DS with the increasing FLG allele contributed from Lakin.  The major QTL on 3AL, QFlg.hwwgr-3AL, explained 17.5–37.8% of the phenotypic variation in different environments.  QFlg.hwwgr-3AL was located in a 4.4-cM interval on chromosome 3AL that was flanked by two markers IWA1831 and IWA8374.  Another QTL for FLG on 2DS, designated as QFlg.hwwgr-2DS which was identified only in Yangling in 2014 (YL14), was flanked by IWA1939 and Xgwm261 and accounted for 11.3% of the phenotypic variation for FLG.  QFlg.hwwgr-3AL and QFlg.hwwgr-2DS showed Additive×Environment (AE) interactions, explaining 3.5 and 4.4% of the phenotypic variance, respectively.  Our results indicated that different genes/QTLs may contribute different scores of FLG in a cultivar and that the environment may play a role in FLG.

Avian influenza (AI), caused by the influenza A virus, has been a global concern for public health. AI outbreaks not only impact the poultry production, but also give rise to a risk in food safety caused by viral contamination of poultry products in the food supply chain. Distinctions in AI outbreak between strains H5N1 and H7N9 indicate that early detection of the AI virus in poultry is crucial for the effective warning and control of AI to ensure food safety. Therefore, the establishment of a poultry surveillance system for food safety by early detection is urgent and critical. In this article, methods to detect AI virus, including current methods recommended by the World Health Organization (WHO) and the World Organisation for Animal Health (Office International des Epizooties, OIE) and novel techniques not commonly used or commercialized are reviewed and evaluated for feasibility of use in the poultry surveillance system. Conventional methods usually applied for the purpose of AI diagnosis face some practical challenges to establishing a comprehensive poultry surveillance program in the poultry supply chain. Diverse development of new technologies can meet the specific requirements of AI virus detection in various stages or scenarios throughout the poultry supply chain where onsite, rapid and ultrasensitive methods are emphasized. Systematic approaches or integrated methods ought to be employed according to the application scenarios at every stage of the poultry supply chain to prevent AI outbreaks.

Grape white rot caused by Coniella vitis is a global concern in the grape industry. pH regulation is essential for cell growth, reproductive processes and pathogenicity in phytopathogenic fungi. In this study, we observed that the growth rate, spore production and virulence of C. vitis significantly declined in alkaline pH, as well as the suppressive effect on secretion of hydrolytic enzymes. Transcriptomic and metabolomic analyses were used to investigate the responses of C. vitis to acidic (pH=5), neutral (pH=7) and alkaline environments (pH=9). We identified 728, 1780 and 3386 differentially expressed genes (DEGs) at pH 5, pH 7 and pH 9, when compared with the host pH (pH=3), and 2122 differently expressed metabolites (DEMs) in negative and positive ion mode. Most DEGs were involved in carbohydrate metabolic process, transmembrane transport, tricarboxylic acid cycle, peptide metabolic process, amide biosynthetic process, and organic acid metabolic process. In addition, metabolomic analysis revealed ABC transporters, indole alkaloid biosynthesis, diterpenoid biosynthesis, and carotenoid biosynthesis pathways in response to the pH change. Furthermore, we found that the aspartate synthesis metabolic route associated with the TCA cycle is a key limiting factor for the growth and development of C. vitis in alkaline environments, and aspartate supplementation enables C. vitis to grow in alkaline environments. Plant cell wall-degrading enzymes (PCWDEs) could contribute to the pathogenicity, when C. vitis infected at pH 3. Importantly, aflatrem biosynthesis in acidic environment might contribute to the virulence of C. vitis and has a risk of causing human health problems due to its acute neurotoxic effects.