Winter wheat (Triticum aestivum L.) cultivars Yangmai 9 (water-logging tolerant) and Yumai 34 (water-logging sensitive) were subjected to water-logging (WL) from 7 d after anthesis to determine the responses of photosynthesis and anti-oxidative enzyme activities in flag leaf. At 15 d after treatment (DAT), net photosynthetic rate under WL was only 3.7 and 8.9 μmol(CO 2 ) m -2 s -1 in Yumai 34 and Yangmai 9, respectively, which was much lower than in the control. Ratios of variable to maximum and variable to initial fluorescence, actual photosynthetic efficiency, and photochemical quenching were much lower, while initial fluorescence and non-photochemical quenching were much higher under WL than in control, indicating damage to photosystem 2. WL decreased activities of superoxide dismutase and catalase in both cultivars, and activity of peroxidase (POD) in Yumai 34, while POD activity in Yangmai 9 was mostly increased. The obvious decrease in the amount of post-anthesis accumulated dry matter, which was redistributed to grains, also contributed to the grain yield loss under WL.

Breeding durable resistance to pathogens and pests is a major task for modern plant breeders and pyramiding different resistance genes into a genotype is one way of achieving this. Three powdery mildew resistance gene combinations, Pm2+Pm4a, Pm2+Pm21, Pm4a+Pm21 were successfully integrated into an elite wheat cultivar ‘Yang047′. Double homozygotes were selected from a small F2 population with the help of molecular markers. As the parents were near‐isogenic lines (NILs) of ‘Yang158′, the progenies showed good uniformity in morphological and other non‐resistance agronomic traits. The present work illustrates the bright prospects for the utilization of molecular markers in breeding for host resistance.

No abstract

Changes of sucrose metabolism in the subtending leaf to cotton (Gossypium hirsutum L.) boll at different fruiting branch nodes (FBN) were investigated. Two cotton cultivars, Kemian 1 and Sumian 15, were grown in the field at three planting dates in 2009 and 2011. Cotton planted on different dates but experiencing similar climatic factors flowered on the same date and had similar boll opening dates, but had different FBN. In the present study, boll weight and carbohydrate content were significantly affected by both flowering date (FD) and FBN. However, only cystolic fructose-1,6-bisphosphatase (cy-FBPase) and sucrose-phosphate synthase (SPS) activities of the sucrosemetabolizing enzymes were influenced significantly by FBN, and the influence of FBN was lower with delayed FD. In general, effects of FBN on boll weight and sucrose metabolism in the subtending leaf were higher at the optimal FD (13 August) than those at later FD (9 September 2009 and 2 September 2011), and total fruiting branches were used to characterize cotton physiological age in the current study. Sucrose transport capacity (Tn) and SPS in the subtending leaf had significantly positive correlations with boll weight at 17-24 days post anthesis (DPA), a crucial period when boll weight was significantly affected. In addition, higher SPS activity was favourable for sucrose export and boll weight during boll development.

This study was conducted to evaluate the effects of supplemental common yeast culture (CY) and glycerol-enriched yeast culture (GY) on performance, plasma metabolites, antioxidant status, and heat shock protein 70 (HSP70) mRNA expression in lactating Holstein cows under heat stress. During summer months, 30 healthy multiparous lactating cows (parity 3.25 ± 0.48; 60 ± 13 d in milk [DIM]; 648 ± 57 kg BW; an average milk yield of 33.8 ± 1.6 kg/d) were blocked by parity, previous milk yield, and DIM and randomly allocated to 3 dietary treatments: no supplemental yeast culture (Control), 1 L/d of CY (33.1 g yeast) per cow, and 2 L/d of GY (153.2 g glycerol and 31.6 g yeast) per cow. During the 60-d experiment, values of air temperature and relative humidity inside the barn were recorded hourly every 3 d to calculate temperature-humidity index (THI). Weekly rectal temperatures (RT) and respiration rates and daily DMI and milk yield were recorded for all cows. Milk and blood samples were taken twice monthly, and BW and BCS were obtained on d 0 and 60. In this experiment, THI values indicated cows experienced a moderate heat stress. Cows supplemented with CY and GY had greater yields of milk, energy-corrected milk and milk fat, and milk fat percent but lower HSP70 mRNA expression in peripheral blood lymphocytes than Control cows (P < 0.05). Supplementing CY and GY tended (P < 0.15) to decrease RT at 1400 h, increase milk protein yield and erythrocyte glutathione, and reduce plasma urea nitrogen compared with Control. Lower plasma NEFA concentration and HSP70 mRNA expression in peripheral blood lymphocytes (P < 0.05) and tendencies towards greater plasma glucose concentration (P = 0.11) but less BW loss (P = 0.14) were observed in GY relative to CY cows. In conclusion, either CY or GY supplementation partially mitigated the negative effects of heat stress on performance and HSP70 mRNA expression of lactating cows, and GY supplementation provided additional improvements in energy status and HSP70 gene expression of lactating cows.

To characterize changes in ruminal epithelial bacterial communities and immune-related gene expression during concentrate starter feeding before weaning in lambs, 6 pairs of 10-d-old Hu lamb twins were selected: 1 kid received milk (M, = 6), and the other received milk plus starter (M+S, = 6). All lambs received hay and water ad libitum and were slaughtered at 56-d-old. Their rumen fluid was collected to determine ruminal pH and VFA levels; rumen epithelia were collected to characterize their bacterial communities using Illumina MiSeq sequencing and to determine mRNA expression of immune-related genes using quantitative real-time PCR (qRT-PCR). Results showed that starter feeding caused a decreased ruminal pH ( = 0.004) and increased concentrations of acetate, propionate, butyrate, and total VFA ( < 0.001). Principal coordinate analysis and analysis of molecular variance revealed that starter feeding affected ruminal epithelial bacterial communities in the lambs ( = 0.001), with higher relative abundance of dominant taxa , unclassified BS11 gut group, , unclassified Synergistaceae, , , , , and ( < 0.05) but lesser relative abundance of , unclassified Bacteroidales, unclassified Candidate, unclassified RF9, and ( < 0.05). Additionally, a phylogenetic investigation of communities by reconstruction of unobserved states analysis indicated that starter feeding markedly increased relative abundance values of dominant ruminal epithelial bacterial-inferred genes related to other ion-coupled transporters, pentose and glucuronate interconversions, glycosyltransferases, other glycan degradation, AA metabolism, sphingolipid metabolism, biotin metabolism, glycosphingolipid biosynthesis-globo series, and lysosome ( < 0.05) but decreased relative abundance values of genes related to carbon fixation pathways in prokaryotes and energy metabolism ( < 0.05) in the lambs. The qRT-PCR results showed that starter feeding decreased the relative mRNA expression of IL-6 ( = 0.003), IL-10 ( = 0.013), and interferon γ ( = 0.003). Collectively, this study showed that starter feeding could alter ruminal epithelial bacterial communities and some key immune-related genes' expression in preweaned lambs. All these responses of ruminal epithelial bacteria and the immune system would be beneficial for starter-fed lambs to be weaned.

The objectives of this study were to examine the clinical response, changes in ruminal bacterial microbiota, and inflammatory response in lamellar tissues during oligofructose-induced laminitis. Ten fistulated sheep were randomly assigned into a control group ( = 5) and a treatment group ( = 5). The treatment group was infused with oligofructose (21 g/kg BW) by rumen cannula, and the control group was sham-treated with saline. Results showed that all 5 sheep treated with oligofructose developed anorexia and diarrhea 8 to 12 h after the administration of oligofructose. By 12 to 24 h after treatment, the treatment group developed lameness and roach back. Compared with the control group, oligofructose administration decreased ( < 0.001) the rumen pH and concentrations of total VFA and increased ( < 0.001) the level of lactic acid in the rumen. Microbial data analysis revealed that oligofructose infusion increased the abundance of ( = 0.009) and ( = 0.008) and decreased the percentage of unclassified Christensenellaceae ( = 0.028), unclassified Ruminococcaceae ( = 0.009), ( = 0.016), unclassified Lachnospiraceae ( = 0.009), and ( = 0.009) compared with the control group. Oligofructose infusion decreased the ACE ( = 0.047) and Shannon ( = 0.009) indices compared with the control group. The histomorphology analysis revealed that oligofructose overload resulted in damage to the dermoepidermal junction in the lamellar tissue of sheep. Quantitative real-time PCR results showed that compared with the control group, the mRNA expression of membrane-type metalloproteinase-1 ( = 0.049) was downregulated whereas the expression of proinflammatory IL-6 ( = 0.004) and matrix metalloprotease-9 ( = 0.037) was upregulated in the lamellar tissues of the oligofructose treatment group. In general, the present study provides the foundation for a sheep model of oligofructose-overload-induced acute laminitis that could be used in later experiments. Our findings suggest that intraruminal infusion of oligofructose altered ruminal microbiota and resulted in acute laminitis and that the inflammatory damage to the lamellae tissue may be related to the upregulation of matrix metalloprotease-9. The information generated will provide more insight into the systemic effects of lameness caused by oligofructose overload in sheep.

Duck hepatitis A virus type 1 (DHAV-1) is one of the main pathogens of ducklings and causes a high mortality rate. Baicalin (BA) has potent antiviral effect, but the solubility is very poor. In order to increase the absorption, solubility, and pharmacological activity, the phospholipid complex was used to modify BA in present study. Therefore, BA phospholipid complex (BAPC) was prepared. The anti-DHAV-1 abilities of BA and BAPC in vitro was evaluated by cell counting kit-8 and reverse transcription quantitative PCR. The curative effects of BA and BAPC on ducklings which were infected by DHAV-1 in addition to the ALT and AST levels were also detected. The results indicated the anti-DHAV-1 ability of BAPC was stronger than that of BA both in vitro and in vivo. To explore the anti-DHAV-1 mechanism, the influence of BAPC on DHAV-1 adsorption, replication, and release was studied. Furthermore, the anti-oxidative and immuno-enhancing abilities of BAPC in the treatment of infected ducklings were also determined. The results showed BAPC inhibited DHAV-1 adsorption, replication and release. Furthermore, it played anti-oxidative and immno-enhancing roles in the treatment, and the immno-enhancing role was crucial to the treatment.