[Effect of Long-Term Biochar Application on Soil Respiration in Flue-Cured Tobacco Planting Fields in Henan Province].

A five year (2013-2017) experiment was conducted to explore the effects of biochar application on the dynamic changes in soil respiration, soil water, and heat factors under four treatments:CK (without biochar), T1 (with 1.5 t·hmbiochar), T2 (with 15 t·hmbiochar), and T3 (with 45 t·hmbiochar). The results showed that:① the soil respiration rate in the growing season of flue-cured tobacco was significantly reduced by 25.

[Effect of Biochar Amendment on Physicochemical Properties and Fungal Community Structures of Cinnamon Soil].

To identify the effect of biochar addition on soil abiotic and biotic properties and provide evidence for the soil improvement with biochar input, the soil physiochemical properties and fungal community were investigated in a cinnamon soil after 3-year biochar additions of 10, 20, and 40 t ·hm. The relationship between the fungal community and edaphic physicochemical characteristics was also analyzed. The results showed that soil pH, moisture, total nitrogen (TN), and total organic carbon (TOC) significantly increased but dissolved organic carbon (DOC) content and soil bulk density decreased with biochar addition.

[Effects of phosphorus fertilizer on the root system and its relationship with the aboveground part of flue-cured tobacco].

Using 'Yuyan 10' as the material, the effects of different phosphorus fertilizer application on root characteristics of tobacco, such as root dry mass and the difference of dry matter distribution and mineral nutrient accumulation between its above and underground parts were investigated. The results showed that the growth of flue-cured tobacco root system and the distribution of dry matter to the aboveground part were significantly promoted by phosphorus fertilizer application. The application of 30 kg P2O5 · hm(-2) led to the maximums of root dry mass, root volume, root activity and the minimum of root to shoot ratio.

Canopy and leaf gas exchange of Haloxylon ammodendron under different soil moisture regimes.

In order to reveal the drought resistance and adaptation of the C(4) desert plant Haloxylon ammodendron under artificially controlled soil moisture regimes, representative plants were selected to measure canopy photosynthesis using canopy photosynthetic measurement system. The results showed that appropriate soil moisture significantly enhances the canopy and leaf photosynthetic capacity, and extremely high soil moisture is not conducive to the photosynthesis of H. ammodendron.

[Effects of farmland shelterbelt on photosynthetic characteristics and grain yield of maize in Hexi corridor oasis].

Farmland shelterbelt is a main component of oasis agro-ecosystem in the Hexi corridor of Gansu Province, which plays an important role in maintaining local agricultural production and ecological balance. This paper studied the photosynthetic characteristics of maize at its grain-filling stage and the grain yield of maize under the protection of the shelterbelt. The results showed that at the same distances east and west of the shelterbelt, maize plants at the east side always intercepted more photosynthetic active radiation (PAR) than those at the west side.

[Analysis of RAPD on medicinal plants of Codonopsis pilosula].

Objective: To study genetic diversity and genetic relationship among 9 cultivated and 4 nature populations of Codonopsis pilosula and C. pilosula var. modesta form Gansu Province at DNA level.