Starch is the most important component in endosperm of sorghum grain.  Usually, two types of starch are present: amylose (AM) and amylopectin (AP).  The levels of AM and AP contents play a significant role in the appearance, structure, and quality of sorghum grains and in marketing applications.  In the present study, a panel of 634 sorghum (Sorghum bicolor (L.) Moench) accessions were evaluated for starch, AM, and AP contents of grain, which included a mini core collection of 242 accessions from the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) in India, and 252 landraces and 140 cultivars from China.  The average starch content was 67.64% and the average AM and AP contents were 20.19 and 79.81%, respectively.  We developed a total of 260 000 high-confidence single nucleotide polymorphism (SNP) markers in the panel of 634 accessions of S. bicolor using specific locus amplified fragment sequencing (SLAF-seq).  We performed genome-wide association studies (GWAS) of starch, AM, and AM/AP of grain and SNP markers based on a mixed linear model (MLM).  In total, 70 significant association signals were detected for starch, AM, and AM/AP ratio of grain with P<4.452×10^–7, of which 10 SNPs were identified with significant starch, 51 SNPs were associated with AM, and nine SNPs were associated with the AM/AP ratio.  The Gene Ontology (GO) analysis identified 12 candidate genes at five QTLs associated with starch metabolism within the 200-kb intervals, located on chromosomes 1, 5, 6, and 9.  Of these genes, Sobic.006G036500.1 encodes peptidyl-prolyl cis-trans-isomerase CYP38 responsible for hexose monophosphate shunt (HMS) and Sobic.009G071800 encodes 6-phospho-fructokinase (PFK), which is involved in the embden-meyerhof pathway (EMP).  Kompetitive allele specific PCR (KASP) markers were developed to validate the GWAS results.  The C allele is correlated with a high starch content, while the T allele is linked with a low level of starch content, and provides reliable haplotypes for MAS in sorghum quality improvement.

    Alfalfa (Medicago sativa) is difficult to ensile successfully because of the low content of moisture and water-soluble carbohydrates (WSC) in fresh alfalfa and the high buffering capacity in fresh alfalfa. Here, we conducted a study to evaluate the effects of three lactic acid bacteria (LAB) inoculants (Lactobacillus casei, Lactobacillus plantarum, and Pediococcus pentosaceus) on silage quality, in situ ruminal degradability, and in vitro fermentation of alfalfa silage. The first cut of alfalfa was wilted, chopped, and randomly divided into four groups: the control (CON) and control mixed with three separate LAB inoculants (106 cfu g^–1). Simmental steers with a body weight of (452±18) kg and with installed rumen fistulas were prepared for in situ degradation and for in vitro gas production. LAB inoculants had a lower (P<0.05) content of butyric acid than the CON group. Among them, the L. casei inoculated silage had a higher (P<0.05) content of water-soluble carbohydrate (WSC) and a lower (P<0.05) NH3-H content. The effective degradation (ED) of crude protein in LAB inoculation decreased (P<0.05), while the ED of acid detergent fiber increased (P<0.05) in situ fermentation. The alfalfa silage with LAB inoculants produced more carbon dioxide (P<0.05). The NH3-H content of mixed incubation fluid in L. casei inoculated silage was lower (P<0.05) compared with other groups. Therefore, this study showed that LAB inoculants could improve both ensiling quality and degradation. In particular, the L. casei inoculations exhibited better performance by limiting proteolysis during ensiling.

Excessive use of N fertilizer in intensive agriculture can increase crop yield and at the same time cause high carbon (C) emissions. This study was conducted to determine optimized N fertilizer application for high grain yield and lower C emissions in summer corn (Zea mays L.). A field experiment, including 0 (N0), 75 (N75), 150 (N150), 225 (N225), and 300 (N300) kg N ha–1 treatments, was carried out during 2010–2012 in the North China Plain (NCP). The results showed that grain yield, input energy, greenhouse gas (GHG) emissions, and carbon footprint (CF) were all increased with the increase of N rate, except net energy yield (NEY). The treatment of N225 had the highest grain yield (10 364.7 kg ha–1) and NEY (6.8%), but the CF (0.25) was lower than that of N300, which indicates that a rate of 225 kg N ha–1 can be optimal for summer corn in NCP. Comparing GHG emision compontents, N fertilizer (0–51.1%) was the highest and followed by electricity for irrigation (19.73–49.35%). We conclude that optimazing N fertilizer application rate and reducing electricity for irrigation are the two key measures to increase crop yield, improve energy efficiency and decrease GHG emissions in corn production.

Pharmacokinetics of cyadox (CYX) and its major metabolites in healthy swine was investigated in this paper. 1,4- Bisdesoxycyadox (BDCYX), cyadox-1-monoxide (CYX-1-O) and quinoxaline-2-carboxylic acid (QCA), three main metabolites of cyadox, were synthesized by College of Science, China Agricultural University. Cyadox (CYX) was administered to 8 healthy cross-bread swine intravenously (i.v.) and orally (p.o.) at a dosage of 1 mg kg-1 body weight and 40 mg kg-1 body weight respectively in a randomized crossover design test with 2-wk washout period. A sensitive high-performance liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS) method was developed for the determination of cyadox and its major metabolites in plasma. CYX and its major metabolites BDCYX, and CYX-1-O can be detected after intravenous administration of cyadox while CYX and its metabolites BDCYX, CYX-1-O and QCA can be detected after oral administration of CYX. Plasma concentration vs. time profiles of CYX and its major metabolites were analyzed by non-compartmental pharmacokinetic method. Following i.v. administration, the areas under the plasma concentration-time curve (AUC0- ) were (0.38±0.03) μg mL-1 h (CYX), (0.018±0.002) μg mL-1 h (BDCYX) and (0.17±0.02) μg mL-1 h (CYX-1-O), respectively. The terminal elimination half-lives (t1/2lz) were determined to be (0.93±0.07) h (CYX), (1.45±0.04) h (BDCYX), and (0.92±0.04) h (CYX-1-O), respectively. Steady-state distribution volume (Vss) of (2.14±0.11) L kg-1 and total body clearance (CL) of (2.84±0.19) L h-1 kg-1 were determined for CYX after i.v. dosing. The bioavailability (F) of CYX was 2.85% for oral administration. After single i.v. administration, peak plasma concentrations (Cmax) of (1.08±0.06) μg mL-1 (CYX), (0.0068± 0.0004) μg mL-1 (BDCYX) and (0.25±0.03) μg mL-1 (CYX-1-O) were observed at Tmax of 0.033 h (CYX), 1 h (BDCYX) and 0.033 h (CYX-1-O), respectively. The main pharmacokinetic parameters after p.o. administration were as follows: AUC0- were (0.42±0.04) μg mL-1 h (CYX), (1.38±0.14) μg mL-1 h (BDCYX), (0.59±0.02) μg mL-1 h (CYX-1-O) and (1.48±0.09) μg mL-1 h (QCA), respectively. t1/2lz were (4.77±0.33) h (CYX), (5.77±0.56) h (BDCYX), (4.12±0.28) h (CYX-1-O), and (8.51±0.39) h (QCA), respectively. After p.o. administration, Cmaxs of (0.033±0.002) μg mL-1 (CYX), (0.22±0.03) μg mL-1 (BDCYX), (0.089±0.005) μg mL-1 (CYX-1-O), and (0.17± 0.01) μg mL-1 (QCA) were observed at Tmax of (7.38±0.33) h (CYX), (7.25±0.31) h (BDCYX), (7.38±0.33) h (CYX-1-O), and (7.25±0.31) h (QCA), respectively. The results showed that CYX was slowly absorbed after oral administration and most of CYX was transformed to its metabolites in swine. The area under plasma concentration-time curve (AUC0- )of metabolites were higher than that of CYX after p.o. administration, and the elimination half-lives (t1/2lz) of QCA were longer than those of CYX, CYX-1-O, and BDCYX after oral administration.

In order to provide technological support for risk estimation of pesticide residues taken from vegetables, the residues of pesticide in vegetables in Jinan City, China, were investigated. Moreover, the variability of pesticide residues in vegetables was explored, and the variability factor was calculated. The level of pesticide residue was studied by statistical method. The variability factor was calculated using the Harrell-Davis method in accordance with principles recommended by the JMPR. In addition, the procedure of evaluation was validated according to the principles laid down by the JMPR (Joint Meeting on Pesticide Residues). The detection rate of pesticide residues in all marketplace samples was less than 20% in Jinan City. The unqualified rate of vegetables was low (0.6%). The chlorothalonil was found as the pesticide with the highest rate of detection. The vegetables with the highest rate of pesticide residues detected were leafy vegetables. The relationship between variability factor and mean value of concentrations of contaminations was expressed by the formula, v=4.9×Cmean. The pesticide residues in vegetables from Jinan City is low. The evaluated variability factor is larger than that the value recommended by the JMPR, however, less than the default value used for acute intake assessment of pesticide residues in UK in most cases.