[Changes of grain yield and agronomic traits during millet variety replacements in northern Shaanxi, China.] / 陕北谷子品种更替过程中产量及农艺性状的演变.

A field trial was conducted to examine the differences of grain yield and agronomic characters of six millet (Setaria italica) varieties in Yulin, Shaanxi during 2018-2019 growing seasons. Those varieties were planted in northern Shaanxi in different decades (1960s-1970s, 1980s-1990s, 2000s-2010s). The results showed that the grain yield of millet varieties exhibited an increasing trend across all the decades. The average yield of varieties bred from 2000s to 2010s were 0.46 (2018) and 0.66 kg·m-2 (2019), respectively. The yield increased significantly by 22%-53% compared with the bred before 2000s. Changes of plant height, panicle weight, leaf weight and stem weight were similar to that of yield, while one-thousand kernel weight and spike length were relatively stable which did not change significantly across the decades. The flag leaf width increased significantly with the variety replacements. There was a significant correlation between panicle weight, stem weight, leaf weight, plant height and grain yield, respectively. Results of principal component analysis showed that millet varieties bred from 2000s to 2010s had greater advantages. In the process of millet cultivars replacement in northern Shaanxi, yield per unit area was mainly increased through the improvement of plant height and spike weight. In the future, we should focus on the improvement of plant height, spike weight, stem weight, and leaf weight, especially the exploration of the optimal plant height suitable for mechanical harvesting.

Supplemental Nicotinamide Dose-Dependently Regulates Body Phosphorus Excretion via Altering Type II Sodium-Phosphate Co-Transporter Expressions in Laying Hens.

BACKGROUND: Dietary supplemental nicotinamide is used to treat hyperphosphatemia in humans. However, the mechanisms of its impact on body phosphorus homeostasis remain unclear. OBJECTIVE: This study was to determine effects and molecular mechanisms of 3 dietary nicotinamide concentrations on body phosphorus homeostasis in laying hens. METHODS: Hy-Line Brown layers (total = 21; 40 wk old; body weight: 1,876 ± 24 g) were individually housed (n = 7) and fed a corn-soybean meal-based diet supplemented with nicotinamide at 20 (N20), 140 (N140), and 1000 (N1000) mg/kg for 21 d. Serum phosphorus and fibroblast growth factor 23 (FGF23) concentrations, phosphorus and calcium excretion, and mRNA and/or protein of type II sodium-phosphate co-transporters (NPt2a, NPt2ab) and FGF23 and FGF23 receptors were measured in the intestines, calvaria, kidney, and liver. RESULTS: Hens in the N1000 group had a 16% lower serum phosphorus concentration and 22% greater phosphorus excretion than those in the N20 or N140 group (P ≤ 0.05). Compared with hens in the N20 group, hens in the N140 and N1000 groups, which did not differ, had 15-21% lower serum FGF23 concentrations, 19-22% greater calcium excretion, 43-56% lower ileum NPT2b protein production, and 1.5- to 1.6-fold greater kidney NPT2a protein production, respectively (all differences at P ≤ 0.05). CONCLUSIONS: Supplementing high concentrations of nicotinamide in diets for laying hens led to accelerated phosphorus and calcium excretions and decreased serum phosphorus and FGF23 concentrations, which were associated with downregulated intestinal NPt2b protein production. Our findings exclude kidney NPt2a protein production as a primary mechanism for the nicotinamide-induced body phosphorus loss.

The complete mitochondrial genome of the pen shell Atrina pectinata (Mollusca: Bivalvia: Pinnidae): the first representative from the family Pinnidae.

In this study, we described the complete mitochondrial genome of the pen shell Atrina pectinata. It was 16,811 bp in length and consisted of 35 genes including 12 protein-coding genes, 2 ribosomal RNAs, and 21 transfer RNAs (trnS2 and atp8 lacked). All genes were encoded on the same strand. In gene order, there was no completely identical block compared to those of Mytilus edulis, Crassostrea gigas, Chlamys farreri and Venerupis philippinarum. It may be a ground pattern of Pinnidae mitochondrial genomes.