Density and row spacing of short-season cotton suitable for machine picking in the cotton region of Yellow River Basin.

To determine the suitable planting density and row spacing of short-season cotton suitable for machine picking in the Yellow River Basin of China, we conducted a two-year field experiment in Dezhou during 2018-2019. The experiment followed a split-plot design, with planting density (82500 plants·hm-2 and 112500 plants·hm-2) as the main plots and row spacing (equal row spacing of 76 cm, wide-narrow row spacing of 66 cm+10 cm, equal row spacing of 60 cm) as the subplots. We examined the effects of planting density and row spacing on growth and development, canopy structure, seed cotton yield and fiber quality of short-season cotton. The results showed that plant height and LAI under high density treatment were significantly greater than those under low density treatment. The transmittance of the bottom layer was significantly lower than under low density treatment. Plant height under 76 cm equal row spacing was significantly higher than that under 60 cm equal row spacing, while that under wide-narrow row spacing (66 cm +10 cm) was significantly smaller than that under 60 cm equal row spacing in peak bolling stage. The effects of row spacing on LAI varied between the two years, densities, and growth stages. On the whole, the LAI under the wide-narrow row spacing (66 cm+10 cm) was higher, with the curve declining gently after the peak, and it was higher than that in the two cases of equal row spacing in the harvest time. The change in transmittance of the bottom layer presented the opposite trend. Density, row spacing, and their interaction had significant effects on seed cotton yield and its components. In both years, seed cotton yield was the highest (3832 kg·hm-2 in 2018, 3235 kg·hm-2 in 2019) under wide-narrow row spacing (66 cm+10 cm), and it was more stable at high densities. Fiber quality was less affected by density and row spacing. To sum up, the optimal density and row spacing of short-season cotton were as follows: density with 112500 plants·hm-2 and wide-narrow row spacing (66 cm+10 cm).

Study on Adsorption and Desorption Characteristics of Cd2+ and Cu2+ on the Surface Sediments of Sanhuhekou of Yellow River by Using ICP-MS.

In order to study the interaction mechanism between Cd2+, Cu2+ and surface sediments in the upper reaches of the Yellow River, the surface sediment of Sanhuhekou (YRSSM) was chosen as research object with inductively coupled plasma mass spectrometry (ICP-MS) as analysis method. The adsorption reaction condition such as liquid-solid ratio, reaction time and pH were optimized, and the adsorption and desorption characteristics of Cd2+ and Cu2+ onto the surface sediments under the optimized experimental conditions were studied. The results showed that the adsorption capacity of Cu2+ was greater than that of Cd2+, the equilibrium absorption capacity were 0.88 and 0.13 mg·g-1 under each optimum experimental condition, respectively. The adsorptions of Cu2+ and Cd2+ were in accord with the pseudo-second-order kinetic, while adsorption rate of Cu2+ was also greater than that of Cd2+. The adsorption thermodynamics data were in accordance with the Freundlich model and the fitting. Results showed that the adsorption process of Cu2+ and Cd2+ belonged to the preferential adsorption, and were endothermic and spontaneous processes. The desorption process showed that the Elovich equation were suitable for Cd2+ and Cu2+ and belonged to the heterogeneous diffusion. Multi-ions competitive adsorption and desorption experiments indicated that Cu2+ was influenced more by co-existing ion. The study revealed not only the mechanism of adsorption and desorption between Cd2+, Cu2+ and surface sediment in Sanhuhekou, but also the influence of coexisting ions on the adsorption and desorption characteristics. The results demonstrated that the distribution mechanism of heavy metals between solid-liquid phases, and provided a theoretical basis for the migration ability of heavy metals. It also had a guiding significance for establishing heavy metals preventive and control measures of the study area.

[Effect of selenium-enriched garlic on chronic gastritis of the glandular stomach of Mongolian gerbils induced by H. pylori].

OBJECTIVE: To detect the therapeutic effect of selenium-enriched garlic (SeG) on chronic gastritis. METHODS: Chronic gastritis was induced of the glandular stomach of male Mongolian Gerbils via gastric instillation of H. pylori TN2 strain once every 4 days for 5 consecutive times followed by random classification into six groups. Fresh SeG suspension was administrated daily at dosages of 4.70, 1.5, 0.47, 0.15 g.kg(-1).d(-1) for four weeks. The gerbils in the positive control group were treated with omeprazole, clarithromycin, and amoxicillin for one week. The gerbils were killed for pathological examination four weeks after SeG-treatment. RESULTS: Chronic gastritis (CAG), low-grade dysplasia or gastric intraepithelial neoplasia (DYS/GIN) were observed among 77% and 38.5% of the 13 H. pylori-treated animals in the negative control group, respectively; whereas 40% and 26.7% in the positive control group (n = 15), respectively. The incidences of CAG and DYS/GIN in the SeG groups (n = 21 - 27) were reduced dose-dependently, 16.7% - 38.7% and 11.1% - 14.3% for CAG and DYS/GIN, respectively. CONCLUSION: SeG administration inhibits the development and progression of CAG induced by H. pylori remarkably.