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[Objective] The present paper aimed to isolate and identify mixed infections of Escherichia coli and Eimeria in a large-scale sheep farm in Ningxia and analyze the histopathological changes of target organs. [Method] Solid culture medium was used to isolate bacterial patho- gens, and saturated saline floating method was used to detect parasites. The gene sequence was amplified and sequenced using 16S rRNA primers from E. coli, and the DNA Star software was used to compare the sequencing results of the isolated strains with the sequence of the standard strains in GenBank. The adjacency method in MEGA 7.0 software was used for genetic evolution analysis. The phylogenetic tree of isolates was constructed based on 16S rRNA using the adjacency method in MEGA 7.0 software. The target organ tissues were subjected to histopathological observation. [Result】 A metallic black single colony was observed in eosin methylene blue medium, and a grey circular sin- gle colony with a hemolytic ring was observed in the blood plate. It was stained as Gram negative bacilli. A total of 3 strains were isolated. McMaster test showed that there were ovoid, smooth surface sporulated Eimeria oocysts in the feces, with an average OPG of 2200, indicating a mild infection. The amplified fragment of 16S rRNA from three strains was consistent with the positive control, and the phylogenetic tree constructed based on 16S rRNA gene sequence was in the same branch as E. coli. Histopathological observation showed that the number of lymphocytes in mesenteric lymph nodes decreased and neutrophils infiltrated. There was dissolution and necrosis of villi in the mucosal layer of intestinal tissue, and loss of mucosal epithelial structure. There were coccidia bodies in the lamina propria of the ileum, which were eosin-ophilic and round in shape. There were neutrophils infiltrating the interstitium of the jejunum, and there were schizoites of coccidia falcifor- mis in the glandular cavity. There were ulcerative foci in the local mucosa of the colon, with a large amount of weakly basophilic short rod- shaped substances deposited. 【Conclusion】 The comprehensive analysis of pathogenic morphology and molecular biology results showed that the diarrhea in this sheep group was caused by the co-infection of E. coli and Eimeria. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to the effects of phosphorus application rate on switchgrass growth and soil nutrients in saline-alkali soil, in order to determine the appropriate amount of phosphorus, which provided a theoretical basis for saline-alkali soil improvement and high yield and high efficiency cultivation of switchgrass in Yinbei area of Ningxia.【Method】In Yinbei area of Ningxia, switchgrass, an energy crop, was used as material to study the effects of different treatments on the growth, soil saline-alkali content and nutrient absorption and utilization of switchgrass by setting 0,30 and 90 kg/hm² of phosphorus fertilizer（expressed as P0, P30 and P90, respectively） through field experiments.【Result】At the mature stage of switchgrass, the soil salinity and alkali content in 0-100 cm soil layer of each treatment were all P0>P30>P90, and the soil organic matter, available phosphorus and alkali-hydrolyzable nitrogen contents were all P90>P30>P0. Compared with P0, P90 treatment significantly reduced the soil salinity and alkali content and increased the nutrient content. Phosphorus application contributes to the growth of switchgrass, which promoted the absorption and utilization of nitrogen and phosphorus, and improved the accumulation of aboveground dry matter. Under three phosphorus levels, soil nitrogen balance of payments were deficit, and soil phosphorus balance was surplus only under P90 treatment.【Conclusion】The comprehensive results showed that under the conditions of this experiment, 90 kg/hm² P application rate could not only ensure the good growth of switchgrass and obtain high biomass yield, but also alleviate the saline-alkali pressure, improve the soil nutrient status and maintain a reasonable balance of nitrogen and phosphorus. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to understand the influence of planting years on the soil fertility characteristics of wine vine-yards at the eastern foot of Ilelan mountain in Ningxia, and to provide a basis for the sustainable development of wine industry. [Method] vineyard rhizosphere soil and non-rhizosphere soil of 3 years,8 years and 20 years were collected from Ganchengzi district of Qingtongxia city at the eastern foot of Helan mountain in Ningxia, and soil fertility variation characteristics were measured. [Result] The pH value and electrical conductivity of grape rhizosphere soil were higher than that of non-rhizosphere soil regardless of the planting years. The total N, total K, organic carbon and available K in grape soil were increasing first and then decreasing under different planting years. The average content of total N, total K, organic; carbon and available K were the highest at 8 years. The content of alkaline N, available F and total P in grape soil increased with the planting years. There was no significant difference in microbial biomass C, N and P in grape rhizosphere soil and non-rhizosphere soil between 3 years and 20 years. [Conclusion] With the increase of planting years, nutrient enrichment rate in root zone was weaker and weaker, but the soil fertility was accumulated in the vineyard with the planting years. [ABSTRACT FROM AUTHOR]

【Objective】This paper aimed to reveal the characteristics of sap flow and its correlation with major meteorological factors in the dry and water-deficient areas.【Method】The plantation forests in the loess hilly region of southern Ningxia were used as research objects.In June and October 2018,thermal diffusion needles were used.The sap flow,combined with the meteorological factors of the HOB automatic meteorological station,were continuously investigated to analyze the sap flow rate and its influencing factors.【Result】(i)The daily variation of sap flow rate was unimodal on sunny days,and the curve showed a bimodal or multi-peak change in rainy days; The seasonal variation of daily average sap flow rate was wavy,but there was a trend of increasing first and then decreasing; The starting time of liquid flow in June was 6: 30,7-10 months was 8:30.(ii) The daily variation of solar radiation and temperature in each meteorological factor was similar to that of sap flow,and the similarity of other factors was low.(iii) At the growing season scale,solar radiation and temperature were significantly positively correlated with liquid flow rate(P<0.01),and wind speed and liquid flow rate were significantly negatively correlated(P<0.01),and air relative humidity was not correlated.There were differences in meteorological factors affecting sap flow in different months.(iv)A regression model of sap flow rate and main meteorological factors were established to predict the sap flow rate of the mountain sap.【Conclusion】The research results would provide a scientific and technological support for the ecological hydrological process and integrated water resources management of forest trees in the loess hilly area of southern Ningxia. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to investigate the effect of warming on the physiological activities of lily in the 10 leaf stage, 20 leaf stage and bud stage after low temperature stress. 【Method】 A lily cut flower variety, ‘Robina’, commonly seen in greenhouses in Ningxia, was used in the present study. The room temperature(22 ℃/14 ℃ for day/night) was used as the control(CK), and the artificial climate chamber was used to simulate the low temperature environment(8 ℃/2 ℃) for 3, 7, 10 days, followed by warming immediately(temperature increased to room temperature). Then, the activities of superoxide dismutase(SOD), peroxidase(POD) and catalase(CAT), relative conductivity(REC), proline(Pro) and soluble sugar were determined via nitroblue tetrazolium(NBT) photochemical reduction method, guaiacol method, ultraviolet absorption method, conductance instrument method, acid ninhydrin colorimetry and anthrone colorimetry, which could provide a theoretical basis for temperature regulation of solar greenhouse in winter and technical reference for planting management of cut flower lily.【Result】Compared with CK, the activities of SOD, POD and CAT, relative electrical conductivity(REC), proline(Pro) and soluble sugar content of lily leaves increased with the prolongation of treatment time under low temperature stress. After 10 days of stress, they reached 1.03-2.19, 2.96-5.48, 1.94-2.15, 1.58-2.43, 0.72-1.81, 1.35-2.59 times of CK, respectively. The SOD, POD and CAT activities, REC, Pro and soluble sugar content all decreased with the increase of treatment time after warming. After 10 days of warming, each index tends to CK at each stage, which is 1.03-1.49, 1.33-1.55, 1.11-1.14, 1.24-1.39, 0.70-1.05, 0.38-1.10 times of CK, respectively. 【Conclusion】 Overall, the activity of antioxidant enzymes(SOD, POD, CAT), relative electric conductivities and soluble sugar content of lily leaves changed most with temperature during the whole treatment, and increasing the temperature after low temperature stress can alleviate the physiological damage of ‘Robina’ in different growth stages. [ABSTRACT FROM AUTHOR]