Many different chicken breeds are found around the world, their features vary among them, and they are valuable resources.  Currently, there is a huge lack of knowledge of the genetic determinants responsible for phenotypic and biochemical properties of these breeds of chickens.  Understanding the underlying genetic mechanisms that explain across-breed variation can help breeders develop improved chicken breeds.  The whole-genomes of 140 chickens from 7 Shandong native breeds and 20 introduced recessive white chickens from China were re-sequenced.  Comparative population genomics based on autosomal single nucleotide polymorphisms (SNPs) revealed geographically based clusters among the chickens.  Through genome-wide scans for selective sweeps, we identified thyroid stimulating hormone receptor (TSHR, reproductive traits, circadian rhythm), erythrocyte membrane protein band 4.1 like 1 (EPB41L1, body size), and alkylglycerol monooxygenase (AGMO, aggressive behavior), as major candidate breed-specific determining genes in chickens.  In addition, we used a machine learning classification model to predict chicken breeds based on the SNPs significantly associated with recourse characteristics, and the prediction accuracy was 92%, which can effectively achieve the breed identification of Laiwu Black chickens.  We provide the first comprehensive genomic data of the Shandong indigenous chickens.  Our analyses revealed phylogeographic patterns among the Shandong indigenous chickens and candidate genes that potentially contribute to breed-specific traits of the chickens.  In addition, we developed a machine learning-based prediction model using SNP data to identify chicken breeds.  The genetic basis of indigenous chicken breeds revealed in this study is useful to better understand the mechanisms underlying the resource characteristics of chicken.

Genetic improvement has promoted wheat’s grain yield and nitrogen use efficiency (NUE) during the past decades. Therefore, the current wheat cultivars exhibit higher grain yield and NUE than previous cultivars in the Yangtze River Basin, China since the 2000s. However, the critical traits and mechanisms of the increased grain yield and NUE remain unknown. This study explores the mechanisms underlying these new cultivars’ increased grain yield and NUE by studying 21 local cultivars cultivated for three growing seasons from 2016 to 2019. Significantly positive correlations were observed between grain yield and NUE in the three years. The cultivars were grouped into high (HH), medium (MM), and low (LL) grain yield and NUE groups. The HH group exhibited significantly high grain yield and NUE. High grain yield was attributed to more effective ears by high tiller fertility and greater single-spike yield by increasing postanthesis single-stem biomass. Compared to other groups, the HH group demonstrated a longer leaf stay-green ability and a greater flag leaf photosynthetic rate after anthesis. It also showed higher N accumulation at pre-anthesis, which contributed to increasing N accumulation per stem, including stem and leaf sheath, leaf blade, and unit leaf area at preanthesis, and promoting N uptake efficiency, the main contribution of high NUE. Moreover, tiller fertility was positively related to N accumulation per stem, N accumulation per unit leaf area, leaf stay-green ability, and flag leaf photosynthetic rate, which indicates that improving tiller fertility promoted N uptake, leaf N accumulation, and photosynthetic ability, thereby achieving synchronous improvements in grain yield and NUE. Therefore, tiller fertility is proposed as an important kernel indicator that can be used in the breeding and management of cultivars to improve agricultural efficiency and sustainability.

Bread wheat (Triticum aestivum L.) is one of the most important staple crops worldwide.  The phytohormone auxin plays critical roles in the regulation of plant growth and development.  However, only a few auxin-related genes have been genetically demonstrated to be involved in the control of plant architecture in wheat thus far.  In this study, we characterized an auxin-related gene in wheat, TaIAA15, and found that its ectopic expression in rice decreased the plant height and increased the leaf angle.  Correlation analysis indicated that TaIAA15-3B was associated with plant height (Ph), spike length (SL) and 1 000-grain weight (TGW) in wheat, and Hap-II of TaIAA15-3B was the most favored allele and selected by modern breeding in China.  This study sheds light on the role of auxin signaling on wheat plant architecture as well as yield related traits.

Green manure cover crops (GMCCs) planting has a potential for mitigating greenhouse gas emissions (GHG) in agroecosystems and provides important ecosystem services, thereby achieving the Sustainable Development Goals (SDGs) stipulated by the United Nations.  However, the advantages of cultivating GMCCs on arable land are not widely recognized.  For example, in the whole of China, the GMCCs planting area is less than 3.5% of total arable land.  The aim of this study is to explore reasons for the low adoption rate of GMCCs planting.  Using best–worst scaling (BWS) approach, farmers ranked their preferred conservation practices including three types of GMCC cropping systems.  Taking Gansu Province in Northwest China as a case study, a survey with 276 farmers was conducted.  The findings indicated that three factors are related to the low adoption rate of GMCCs: 1) farmers preferred improving farmland irrigation facilities and substituting chemical fertilizers with organic rather than planting GMCCs; 2) lack of awareness and understanding of government policy on GMCCs and limited access to training courses; 3) financial support and subsidies from the government are insufficient.  This study provides insights and strategic implications for policymakers on how to further promote GMCCs in the future.

The fresh postharvest golden needle mushroom (Flammulina velutipes) sporocarp has a high moisture content and crisp texture, but it still has high physiological activity and respiration, leading to senescence and quality deterioration.  Treatments with 1-methylcyclopropene (1-MCP) and polypropylene (PP) crispers were used to study the changes of lignification and softening of F. velutipes during storage.  The main findings were as follows: the crisper packaging could effectively prolong the storage time of F. velutipes; either the 1-MCP treatment, crisper packaging or the combination of the two treatments could significantly inhibit the accumulation of lignin and the decreases in the contents of cellulose and pectin, and had certain inhibitory effects on the activities of enzymes involved in lignification and softening including phenylalanine ammonia-lyase (PAL), cinnamyl alcohol dehydrogenase (CAD), cellulase (Cx), pectin methylesterase (PME) and polygalacturonase (PG).  Among them, the inhibitory effect of the crisper packaging was higher than the 1-MCP treatment, while the combination of the two treatments was the best.  The results of transmission electron microscopy (TEM) and scanning electron microscopy (SEM) showed that the crisper packaging in combination with the 1-MCP treatment could effectively maintain the integrity and stability of the F. velutipes cellular structure and inhibit the emergence of plasmolysis to prevent cell membrane rupture.  The transcription levels showed that the crisper packaging and the combination of the 1-MCP treatment and crisper packing could effectively affect the expression of genes for enzymes related to lignification and softening of F. velutipes.  In conclusion, 1-MCP and PP crispers could delay the lignification and softening of F. velutipes during storage.

Careful soil management is important for the soil quality and productivity improvement of the reclaimed coastal tidal flat saline land in northern Jiangsu Province, China. Farmyard manure (FYM) and mulch applications, which affect soil characteristics and plant significantly, are regard as an effective pattern of saline land improvement. As a conventional management in the study region, FYM and mulch are used for the amendment of the new reclaimed tidal flat regularly, but little is known about their effects on soil physical properties functioning. A study was conducted on a typical coastal tidal flat saline land, which was reclaimed in 2005, to evaluate the effects of FYM, polyethylene film mulch (PM), straw mulch (SM), FYM combined with PM (FYM+PM), FYM combined with SM (FYM+SM), on soil hydraulic properties and soil mechanical impedance. CK represented conventional cultivation in study area without FYM and mulch application and served as a control. The experiment, laid out in a randomized complete block design with three replications, was studied in Huanghaiyuan Farm, which specialized in the agricultural utilization for coastal tidal flat. Result showed that capillary water holding capacity (CHC), saturated water content (SWC), saturated hydraulic conductivity (Ks) and bulk density (BD), cone index (CI) were affected significantly by the FYM and mulch application, especially in the 0-10 cm soil layer. FYM and mulch management increased CHC, SWC and Ks over all soil depth in the order of FYM+SM>FYM+PM>FYM>SM>PM>CK. With the contrary sequence, BD and CI decreased significantly; however, FYM and mulch application affected BD and CI only in the upper soil layers. CHC, SWC and Ks decreased significantly with the increasing of soil depth, BD and CI, and a significant liner equation was found between CHC, SWC, Ks and BD, CI. With the highest CHC (38.15%), SWC (39.55%), Ks (6.00 mm h-1) and the lowest BD (1.26 g cm-3) and CI (2.71 MPa), the combined management of FYM and SM was recommend to be an effective method for the melioration of reclaimed coastal tidal flat saline soil.

The extracts from hulls, brans and flours of Fagopyrum esculentum Möench (FEM, three varieties) and Fagopyrum tartaricum L. Gaerth (FTG, seven varieties) were screened for free and bound phenolic content or total phenolic content (TPC), as well as 1,1 diphenyl-2-picryl hydrazyl (DPPH) free radical scavenging activity and reducing power. Free phenolics were predominant in buckwheat hulls, brans and flours. FEM hulls extract exhibited the highest reducing power and DPPH free radical scavenging activity with the average EC50 84.54 μg mL-1 and IC50 11.54 μg mL-1 respectively, FTG brans extract had the highest average TPC (24.87 mg GAE g-1 DW), and FEM flours extract showed the lowest TPC, reducing power and radical scavenging activity. Furthermore, the correlations among TPC, DPPH free radical scavenging activity and reducing power of all the samples were investigated. The rank correlation coefficient (rs) between reducing power and DPPH free radical scavenging activity of buckwheat hulls, between TPC and DPPH free radical scavenging activity of buckwheat flours were 0.76 and 0.79, respectively (P<0.05). However, there is no significant correlation between the remaining indexes of hulls and flours, as well as the ten buckwheat brans. This result indicated that some non-phenolic compounds also contributed to the total antioxidant activity in hulls, brans and flours of buckwheats. This study demonstrated that buckwheat hulls and brans, rather than flours, are good source of antioxidants.

This study has investigated the suitable drip irrigation scheduling for tomato grown in solar greenhouse based on 20-cm pan evaporation (Epan) in North China Plain. Irrigation treatments included three irrigation frequencies (I1 10, I2 20 and I3 30 mm, and irrigation interval of 2-6 d for I1, 4-9 d for I2 and 8-12 d for I3) based on accumulated pan evaporation (Epan), and four plant-pan coefficients (Kcp1 0.5, Kcp2 0.7, Kcp3 0.9 and Kcp4 1.1). Results indicate that total irrigation amount, seasonal crop evapotranspiration (ET) and tomato yield (Y) were 185.1-365.8 mm, 249.1-388.0 mm and 99.6-151.8 t ha-1, respectively. Irrigation frequency and amount increased the yield, and second-degree polynomial relationship was found between Y and ET (R2=0.8671). Irrigation frequency did not increase mean fruit weight, diameter and length significantly but increased fruit number, total soluble solids content (TSS), TSS yield, fruit firmness and water use efficiency (WUE) and irrigation WUE (IWUE) significantly. Irrigation amount increased external quality of tomato but reduced TSS content, TSS yield, fruit firmness, WUE and IWUE significantly. Kcp3 and Kcp4 treatments had the highest fruit yield, but Kcp2 and Kcp3 treatments had the highest WUE. I1Kcp3 treatment (irrigation interval of 2-6 d, and Kcp=0.9) had higher IWUE, WUE, external quality, yield, and TSS yield, so it is recommended as the suitable irrigation scheduling for tomato grown in solar greenhouse in North China Plain.