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2018 Vol.35(2)

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2018, 12(2): 232-232.
[Abstract](575) [PDF 379KB](76)
Research on the quantitative evaluation of grassland degradation and spatial and temporal distribution on the Mongolia Plateau
Yan-zhen Zhang, Zhao-qi Wang, Yue Yang, Jian-long Li, Ying Zhang, Chao-bin Zhang
2018, 12(2): 233-243. doi: 10.11829/j.issn.1001-0629.2017-0220
[Abstract](815) [FullText HTML] (60) [PDF 2937KB](100)
In this study, we used remote sensing technology to obtain a quantitative evaluation of the present situation of grassland degradation on the Mongolia Plateau. The time scale investigated was 1982 to 2013. We used NDVI data inversion vegetation coverage, and took vegetation coverage in the period 1982-1985 as the main indicator of ecosystem health. Furthermore, we calculated the grassland degradation index(GDI) and evaluated grassland degradation in the Mongolia Plateau during the period 1986-2013 to gain a quantitative estimate of the Mongolia Plateau grassland degradation time and space distribution characteristics. The results showed that the grassland vegetation coverage reached 14.60% and 18.43%, respectively, in the periods 1986-2000 and 2001-2013, with both showing an increase trend. The areas of significant(P<0.05) and highly significant (P<0.01) increase were 298.86 and 189.67 km2 in the period 1986-1999, respectively, and the areas of significant (P<0.05) and highly significant (P<0.01) increase were 443.32 and 92.46 km2 in the period 2001-2013, respectively. Compared with 1986, the worst grassland coverage was in 2007, whereas it was poor in 2001 and 1995. The best grassland coverage was recorded in 2013. In terms of the GDI, in the period 1986-1999, severely degraded grassland area had the largest area percentage(50.35%), whereas in the period 2000-2013, the percentage areas of moderately and seriously degraded grassland were 39.42% and 30.34%, respectively. Collectively,the results showed that grassland degradation conditions are improving on the Mongolia Plateau, from extremely serious and serious degradation to moderate and light grassland degradation.
Analysis of the land use structure change and driving factors in the delta oasis of the Yarkand-Kashghar River over the last 22 years
Aizezitiyuemaier·Maimaiti, Yusufujiang·Rusuli, Baihetinisha·Abudoukerimu, Hui He
2018, 12(2): 244-255. doi: 10.11829/j.issn.1001-0629.2017-0291
[Abstract](795) [FullText HTML] (87) [PDF 2698KB](101)
Land use/Cover Change (LUCC) is one of the hot topics in global change research. In order to understand the rules of LUCC structural change and its attributions in the Yarkant-Kashgar River Delta oasis, this study explored the change process, direction and attribution mechanism of LUCC by methods of change trajectory, dynamic degree and transfer matrix integration of Landsat data, hydrological data, metrological data, and socio-economic data of Yarkant-Kashgar River delta oasis area. The research results showed that: 1) the land cover changed over 22 years of research; evidently, the urban land, vegetation and wetland areas increased about 240.09, 3 908.22, and 539.73 km2, respectively, while water and unused land areas decreased by 464.60 and 4 223.44 km2, respectively. The rate of change in land cover in the latter 10 years was greater than the rate of change in the previous 10 years. 2) The results of change trajectory analysis demonstrated that 66.22% of land use type did not change; the most stable land cover types are layland, followed by vegetation, urban land, water, and wetlands. 3) During the 22 years of research, temperature showed an increasing trend, and reached a significant level; the relative humidity was shown to decrease, and also reached a significant level; precipitation fluctuation was shown to decrease, but did not reach a significant level; population and GDP were shown to increase, but not significantly; the warming and drying of climate, and the rapid growth of population and GDP, to some extent, lead to the increase of urban land and vegetation area and the decrease of water and desert land in the study area.
Effect of grazing on greenhouse gases in grassland ecosystems
Ya-ni Song, Huhe, Yun-xiang Cheng, Fu-jiang Hou, Sheng-hua Chang
2018, 12(2): 256-265. doi: 10.11829/j.issn.1001-0629.2017-0140
[Abstract](831) [FullText HTML] (92) [PDF 588KB](154)
Grazing affects grassland greenhouse gas (GHG) emissions by changing the physical and chemical properties of soil, such as the soil water content, porosity, and microbe and organic matter contents. Respiration of plant roots, soil microbial activities, and various physical, chemical, and biological functions in grassland ecosystems are the main sources of GHGs. Based on the mechanism and function of GHG emissions in grassland ecosystems, this paper reviews the GHG emissions in grassland ecosystems from grazing management, grazing intensity, and grazing animals. The effects of grazing on GHGs in grassland ecosystems, the focus and direction of research prospects, and a summary of the measures taken in different ecosystems to reduce GHGs are discussed in this paper.
Effect of soil moisture fluctuations on CO2 and N2O emission in alpine meadow ecosystem
Rui Wang, Ping Wang, Yong-heng Gao, Gang Ma
2018, 12(2): 266-275. doi: 10.11829/j.issn.1001-0629.2016-0241
[Abstract](762) [FullText HTML] (34) [PDF 903KB](105)
Under the influence of topography and climate, plateau grassland soil experiences frequent soil moisture fluctuations. To explore the influence of soil moisture fluctuations on CO2 and N2O emission from alpine meadows in the Qinghai-Tibet Plateau, we used an undisturbed soil column to simulate soil water content fluctuation from a high (60 cm3·cm-3) to low value (30 cm3·cm-3),and to a high (60 cm3·cm-3) again; this duration of each phase was 38, 57, and 46 days. A soil column with constant HYPERLINK “javascript:;” humidity level (soil humidity 60 cm3·cm-3) was considered the control. The results showed that: 1) soil moisture fluctuations significantly increased CO2 emission. A significant relationship was observed between CO2 emission and soil temperature; additionally, CO2 emission correlated positively with soil dissolved organic carbon (DOC) concentration in the first high soil-water content phase. 2) Moisture fluctuations significantly decreased N2O emission. In the control treatment, there was a strong significant negative correlation between N2O emission and NH4+-N; however, no close relation between N2O emission and NH4+-N level was observed throughout the moisture fluctuation process.
Niche and interspecific associations for dominant species in wetland herb communities in the northern branch of the Zhuozhang River Watershed, Shanxi
Yu Wang, Run-cheng Bi, Wen-ming Ru
2018, 12(2): 276-285. doi: 10.11829/j.issn.1001-0629.2017-0276
[Abstract](861) [FullText HTML] (77) [PDF 573KB](111)
Based on sample investigations of wetland herb communities in the northern branch of the Zhuozhang River Watershed, we analyzed interspecies relationships and niche characteristics for 16 main species. Important findings were as follows: 1) Scirpus triqueter, Polygonum hydropiper, and Cyperus glomeratus showed tendencies of generalized species such as the largest niche breadth among dominant species; 2) a niche overlap of 55% was observed in 0 of 120 species pairs, and lower niche overlap between species indicated weaker interspecific competition; 3) Overall association of phytocoenosium was significantly negative correlation at the 0.05 level, the ratios of positive and negative associations in 2-tests and Pearson correlation coefficients were 0.52 and 0.15; therefore, the negative associations were more than the positive associations, and most interspecific associations were not significant, suggesting that wetland herb communities structure is simple, the interaction between species is weak, the communities are still under dynamic succession; 4) both association coefficients (AC)and Pearson correlation coefficients indicated niche overlap, with the fitting effect of Pearson correlation coefficient showing a stronger positive association than the AC. To provide a theoretical foundation for ecological restoration in the norther branch of the Zhuozhang River Watershed, this study integrated niche characteristics and interspecific associations to understand the dominant species, their interrelations, dynamic characteristics of the communities and current wetland utilization.
Species diversity and characteristics of a Dactylis glomerata community at different elevations in Tarbagatai Shan
Pan-xing He, Xian-hua Zhang, Jin-zhong Zhu
2018, 12(2): 286-296. doi: 10.11829/j.issn.1001-0629.2017-0460
[Abstract](844) [FullText HTML] (46) [PDF 1131KB](237)
For the protection and development of germplasm resources, the quantitative characteristics and species diversity of the Dactylis glomerata community in different elevation areas of a natural grassland were studied in the concentrated area of 1300-1900 m above sea level in Tarbagatai Shan, Xinjiang. The results showed that there was a difference in the number of characteristics in the Tarbagatai Shan; however, there was no regularity in the change. D. glomerata was always the dominant species in the community, and the importance values were more than 35%. When elevation was increased, the variation in α diversity decreased first and then increased, forming a V-shaped curve. The β diversity exhibited higher community similarity, and there were more common species, and the species diversity was negatively correlated with altitude, indicating that the species tended to decrease with altitude. The results of the study revealed a difference in the number and species diversity in the D. glomerata community at different elevations of Tarbagatai Shan area, and the effects of habitat conditions on species composition and diversity.
Adaptability of a malignant invasive plant Parthenium hysterophorus in different types of soil
Xing-xiang Gao, Zuo-wen Sun, Mei Li, Hong Zhu, Mi-ruo Zhao, Jian Li, Feng Fang
2018, 12(2): 297-304. doi: 10.11829/j.issn.1001-0629.2016-0220
[Abstract](855) [FullText HTML] (45) [PDF 807KB](74)
Parthenium hysterophorus is an alien weed that is highly invasive in China. To better understand the potential area of spread for P. hysterophorus, a pot experiment was conducted to study the adaptability of P. hysterophorus in 31 different types of soil. Results showed that P. hysterophorus exhibited strong adaptability to different types of soil. There were 23 types of soil suitable for its growth, which was equivalent to 74.19% of soils tested. The eight types of soil that were not suitable accounted for 25.81%. Moreover, results demonstrated that the growth of P. hysterophorus was not affected by nitrogen, phosphorus, potassium, organic matter content, or soil type, but was affected by pH, soil texture, and salt content of the soil. In particular, it was adversely affected by highly acidic, clay loam or sandy soil and highly saline soil. This indicated that the soil of the mountainous regions of mid-Shandong and plain regions of northwestern Shandong were the most suitable to P. hysterophorus growth, and hill regions of eastern Shandong, plain regions of mid-Shandong and mountainous regions of southern Shandong were appropriate for its growth. However, the coastal regions of northern Shandong and plain regions of southwestern Shandong and low-lying areas were not suitable for P. hysterophorus growth.
The research on the insecticidal activities of Artemisia sphaerocephala extract
Quan Liu, Yuan-hua He, Yong-sheng Li, Chang-yu Liu, Chun-mei Liu, You-nian Wang, Hua Fu
2018, 12(2): 305-310. doi: 10.11829/j.issn.1001-0629.2017-0109
[Abstract](791) [FullText HTML] (114) [PDF 640KB](96)
Artemisia sphaerocephala is a typical eremophyte living in the migratory dunes, and has adopted very well to the extreme climates of arid desert areas; as such, it is usually used as a sand-fixation plant to improve and aid in the recovery of desert environments. The insecticidal activities of the extract obtained from this plant against Tetranychus cinnabarinus and Spodoptera litura are reported for the first time. The phytotoxic activities of this extract on rape, alfalfa, red clover, and bluegrass have also been evaluated in this study. The results of these tests have shown that the extract has obvious acaricidal effects on the two insects and no significant effect on the growths of the host plants. The growths of alfalfa and bluegrass improved under lower concentrations of this extract. The acaricidal activity of the extract was more than 60% at concentrations of 333 μg·mL-1, whereas, the insecticidal activity was more than 50% when concentrations were 20 μg·mL-1. Under the concentrations of 50 and 25 μg·mL-1, respectively, growths of alfalfa and bluegrass were promoted more or less, and the inhibited growth rates of red clover and rape were less than 20%.
Analysis of structures of ecological and areal types of plant species in Horqin sandy land of China
Hui Jiang, Kai Gao, Li-ye Zhou, Xun Tian
2018, 12(2): 311-322. doi: 10.11829/j.issn.1001-0629.2017-0253
[Abstract](871) [FullText HTML] (63) [PDF 867KB](101)
To investigate plant diversity and ecological characteristics of plants in Horqin sandy land, and to reflect environmental change and ecological adaption traits, 56 sample plots were established in 2013. Plants were classified according to growth form of the species, growth form of the roots, Raunkiaer life form, ecological type of water, and areal type. There were 121 species of plants in this region, belonging to 31 families. There were 6 plant growth forms, 5 root growth forms, 6 life forms, 5 ecological water types, and 13 areal types. Gramineae was the most abundant accounting for 23.1% of the plants, and composites and legumes accounted for 22.3% and 11.6%, respectively. Plant growth forms were primarily the vertical type, accounting for 37%, followed by the branch type and cluster type that accounted for 30% and 19%, respectively. Of the root growth forms, the taproot type was the most abundant, accounting for 61%, followed by brush root and rhizome type that accounted for 22% and 15%, respectively. The structure of life style was primarily hemicryptophyte species, accounting for 35%, and annual plants and ground geophytes accounted for 26% and 14%, respectively. The ecological water type was primarily the born in, accounting for 44%, followed by the xeric and mcsoxerophyte type that accounted for 26% and 23%, respectively. Distribution structure of the species was primarily the Mongolian-Northeastern-Dahuricia-North China, accounting for 30%, followed by the Mongolia area and Mongoian-Northeastern-North China areal type that accounted for 18% and 10%, respectively. These results indicate that the Horqin sandy land is at the early stage of ecological recovery. Its flora is complex, with a lack of large changes in water conditions, which are beneficial for the positive succession of plant communities. However, the top soil is still vulnerable, and most of plants are annual plant species. Thus, improvement of grassland management is still needed to protect and properly utilize the plant resources.
Effect of thiophanate methyl on the growth and physiological and biochemical characteristics of Hordeum brevisubulatum-Epichloë bromicola symbionts
Ying Cao, Xiang Yao, Shui-hong Chen, Chun-jie Li
2018, 12(2): 323-330. doi: 10.11829/j.issn.1001-0629.2017-0128
[Abstract](885) [FullText HTML] (113) [PDF 570KB](95)
Hordeum brevisubulatum, a salt-tolerant forage grass species in northern China, was studied to explore the impact of thiophanate methyl on the growth and physiological and biochemical characteristics of endophytic fungi within the wild barley. Results showed that the rate of emergence decreased significantly, from 85% to 72%, after sown seeds were treated with a 500× dilution of thiophanate methyl for 8 h (P<0.05), and the seedling carrier rate decreased significantly from 100% to 12% (P<0.05). Fungicide treatment reduced plant height and tillers of wild barley, whereas chlorophyll, malondialdehyde, and proline content and catalase, peroxidase, and superoxide enzyme activity were not significantly affected (P>0.05), C, N, and P content of wild barley decreased by 4.87%, 10.99%, and 13.50%, respectively, after fungicide treatment, compared with that in the control group (P<0.05). Therefore, treatment of seeds with 500× diluted thiophanate methyl for 8 h was an effective method to eliminate fungal endophytes in H. brevisubulatum.
Physiological and molecular mechanisms of response to drought stress in alfalfa
Sha-sha Li, Hong Li, Wei-guang Yang, Zhao Yang, Xiao-long Wang, Hua Chai
2018, 12(2): 331-340. doi: 10.11829/j.issn.1001-0629.2017-0125
[Abstract](746) [FullText HTML] (48) [PDF 698KB](87)
Alfalfa (Medicago sativa) is a major forage crops throughout the world, and of great nutritional, economic, and ecological value. It is mainly cultivated in the northwestern and northeastern regions of China, where water is the main limiting factor influencing plant yield. In this study, we quantified changes in photosynthesis, respiration, antioxidant activity, osmoregulation, and abscisic acid levels under drought stress, and proposed the mechanisms of physiological response to drought stress in alfalfa. The response process involving transcription factors, protease genes, and drought-resistance genes under drought stress was investigated as well. In conclusion, our study emphasized the importance of response to drought stress in alfalfa from a new perspective.
Physiological integration of antioxidant enzymes and malondialdehyde in connected and disconnected Zoysia japonica clonal ramet under nutrient heterogeneity
Su-nan Xu, Yue Li, Zhong-lin Chen, Li-hong Zhang
2018, 12(2): 341-347. doi: 10.11829/j.issn.1001-0629.2017-0270
[Abstract](817) [FullText HTML] (56) [PDF 539KB](94)
Using a clonal Zoysia japonica plant as the experimental subject, connected and disconnected ramets were treated with different nutrient concentrations, and the study was conducted to analyze changes in antioxidant enzyme activity and malondialdehyde level in Z. japonica under nutrient heterogeneity. The results indicated that parent ramets treated with moderate or high nutrient concentrations had significantly increased the activities of SOD and CAT, and reduced MDA level in connected daughter ramets under nutrient heterogeneity. Contrastingly, daughter ramets treated with moderate or high nutrient concentrations exerted no influence on antioxidant enzyme activity and malondialdehyde level in connected parent ramets. There existed a physiological integration from parent ramets to daughter ramets, and daughter ramets benefited from parent ramets under nutrient heterogeneity; however, parent ramets did not benefit from daughter ramets. Daughter ramets were the unidirectional beneficiaries of the physiological integration.
Evaluation of germination response and the resistance of main plant species seedling to drought stress in the hill-gullied Loess Plateau region of northern Shaanxi
Fang-hong Ge, Ning Wang, Shu Hu, Zheng-chao Zhou, Ping-hai Jiang
2018, 12(2): 348-356. doi: 10.11829/j.issn.1001-0629.2017-0227
[Abstract](668) [FullText HTML] (40) [PDF 553KB](85)
In the hill-gullied Loess Plateau region of northern Shaanxi, lack of soil water is a dominant factor affecting vegetation restoration, and the effect of drought stress on seed germination is a key limiting factor for plant regeneration. This experiment was conducted to estimate the seed germination characteristics and drought resistance of 16 main plant species in the hill-gullied Loess Plateau region. Different concentrations of polyethylene glycol (PEG-6000) solution were used to simulate the drought stress in this study. The results showed that germination of all seeds was subjected to different degrees of inhibition with the increase of PEG concentration. Generally, with drought stress increase, the seed germination time lag was prolonged, or even the seeds did not germinate, and the germination potential, germination rate, germination index, and drought resistance index of all seeds tended to decline. However, slight drought stress (50 g·L-1) promoted the germination of some seeds and increased seed germination potential and germination rate. The comprehensive evaluation of the relative germination potential, relative germination rate, relative germination index, and drought resistance index of 16 species by the membership function method indicated that the drought resistance of Bidens pilosa, Artemisia scoparia, and Setaria viridis was the strongest, and that of Stipa grandis was the weakest.
Response on the clonal growth of Ligularia virgaurea genets to light intensity
Man-tang Wang, Quan-ke Zhao, Dong-liang Cheng
2018, 12(2): 357-362. doi: 10.11829/j.issn.1001-0629.2017-0215
[Abstract](998) [FullText HTML] (46) [PDF 499KB](88)
Understanding the life history strategies of Ligularia virgaurea in the alpine meadow of the Qinghai-Tibet plateau is important to preventing and controlling this weed. We studied the response to light intensity of clonal growth and traits of L. virgaurea genets in field pots experiments to fill the gap in research and provide a theoretical basis for the prevention and control of this weed. Two light intensity levels were used to simulate the light intensities in bare soil and in low, open vegetation of disturbed meadows on the eastern Qinghai-Tibet plateau. The results showed that there was not a linear relationship between the length of rhizomes in L. virgaurea and the time under full natural irradiance. In shaded conditions, there was a significant positive linear relationship between the length of rhizomes in L. virgaurea and time (P<0.05). Light intensity directly affected the dry mass per unit rhizome length. It also indirectly affected the dry mass per unit rhizome length by increasing the dry mass of the genets. There was no trade-off between the length of rhizomes and the dry mass per unit rhizome length in L. virgaurea. Light intensity had a significant impact on relative clonal growth rates of L. virgaurea (P<0.05). The relative clonal growth rates under shaded conditions were significantly higher than those under full natural irradiance. Therefore, the main function of rhizomes is foraging in shaded conditions, but, under the full natural irradiance, their primary role is storage and anchoring.
The distribution and deposition pattern of lignin in alfalfa stem tissue
Jin-qing Zhang, Fen-qi Chen, Fang-zhen Wang, Qiang-en Fang, Shang-li Shi
2018, 12(2): 363-370. doi: 10.11829/j.issn.1001-0629.2017-0403
[Abstract](959) [FullText HTML] (78) [PDF 2242KB](104)
This study tested the occurrence, distribution, and deposition of lignin in stem tissue of the alfalfa variety ‘Gannong No.5’ using the histochemical staining method. The research results showed that the distribution of lignin in the stem of alfalfa is closely related to the vascular tissue in different development stages. At the apex of the stem tissue, lignin is only found in the primary xylem. Then, lignin begins to deposit in the primary phloem fibers, secondary xylem, and pith rays, with the internode moving down.Both guaiacyl (G) lignin and syringyl(S) lignin are present in alfalfa stems, and S lignin occurs later than G lignin. Between the vascular bundles, the deposition pattern of the two kinds of lignin is “vascular bundle near the collenchyma→vascular bundles between the collenchyma”. However, the deposition of lignin shows the heterogeneity within the vascular bundle. The deposition pattern of G lignin is “primary xylem vessels→primary phloem fibers→secondary xylem and pith rays”, while the deposition pattern of S lignin is “primary phloem fibers→secondary xylem and pith rays→pith parenchyma”. It is suggested that the special deposition pattern of lignin in the stem of alfalfa is a strategy that is probably appropriate to the growing environment in the north temperate zone.
Photosynthetic, physiological, and morphological characteristics of Haloxylon ammodendron assimilation twigs in Minqin Oasis
Hua Zhang, Rui Wu, Ya-rong Kang
2018, 12(2): 371-379. doi: 10.11829/j.issn.1001-0629.2017-0133
[Abstract](1014) [FullText HTML] (190) [PDF 607KB](103)
Haloxylon ammodendron is a dominant species in arid zones and plays an important role in regional ecosystem stability. In order to more fully understand the photosynthetic, physiological, and morphological characteristics of H. ammodendron and to determine how they adapt to environmental factors, we employed comparative analytical methods to study these traits at the end of May and the end of July in Minqin Oasis. Our results showed that the change trends for assimilation twigs were bimodal on a daily scale for net photosynthetic rate (Pn), transpiration rate (Tr), and stomatal conductance (Gs) in May and July. The Pn reduction was mainly due to stomatal limitation factors in May; the Pn reduction was caused by non-stomatal limitation factors in July. Morphological characteristics, including area (LA), fresh weight (FW), dry weight (DW), water content (LWC), dry matter content (LDMC), and specific leaf area (SLA) increased by 79%, 94%, 99%, 33%, 14%, and 3%, respectively, in July more than in May. Area was the most representative morphological character of the assimilation twigs. The environmental impact factors of H. ammodendron were mainly photosynthetically active (PAR), air relative humidity (RH), and soil water content (SWC) in May. Other factors of importance were atmospheric temperature (Ta) and SWC in July.
Effect of arbuscular mycorrhiza and a grass endophyte on the drought tolerance of perennial ryegrass
Xiao-yu Wang, Yan-e Guo, Xi Feng, Ying Shi, Ting-yu Duan
2018, 12(2): 380-390. doi: 10.11829/j.issn.1001-0629.2017-0210
[Abstract](1849) [FullText HTML] (58) [PDF 710KB](118)
We established a pot experiment in a greenhouse to study the effects of arbuscular mycorrhiza(AM) fungus and a grass endophyte on perennial ryegrass drought tolerance, aiming to identify two kinds of symbioticmic roorganisms to improve plant drought stress tolerance. The AM treatments involved inoculation with or without arbuscular mycorrhizal fungus.Seeds of perennial ryegrass infected with a grass endophyte (E+) and without grass endophyte (E-) were used to establish plants with and without a grass endophyte, respectively. After 38 days of growth, ryegrass grown in the above microorganism treatments were exposed to four soil water treatments of 15%, 30%, 45%, and 60% of the maximum soil water holding capacity. The mycorrhizalfungus and grass endophyte mostly showed positive effectson plant growth and nutrition uptake in 45% and 60% soil water. The two types of symbiotic fungi not onlypromoted the growth of perennial ryegrass and enhanced shoot and root biomass but also promoted plant nitrogen and phosphorus uptake, enhanced peroxidase activity, and reduced malonaldehyde concentrations.Therefore, the two symbionts enhanced plant drought tolerance and reduced (P<0.05) the damage to perennial ryegrass under semi drought stress.
Effect of five Trichoderma strains on growth and nutritional quality of Orchard grass
Yang Yuan, Yin-chen Wang, Bing Zeng, Jin-hua Zhang, Yu-zhu Han
2018, 12(2): 391-397. doi: 10.11829/j.issn.1001-0629.2017-0149
[Abstract](712) [FullText HTML] (58) [PDF 514KB](128)
In this study, the effects of five Trichoderma strains, 3 strains of Trichoderma harzianum (M1, M2, HM), 1 strain T. longibrachiatum (LM) and T. reesei (LS), on growth and nutrient levels of Dactylis glomerata were evaluated under potting conditions. The results showed that the 5 Trichoderma strains had marked growth-promoting effects on Orchard grass. Compared with the control, the dry weight of the aboveground and underground parts, tiller number, and leaf width of Orchard grass, whose the mean values were increased 0.88 g, 0.40 g, 2.22, 0.31 mm, respectively, and the height and leaf length decreased slightly to 6.31 cm and 7.19 cm, respectively. Trichoderma infection could increase the dry matter, crude ash, crude protein, crude fat and calcium, and phosphorus contents of the Orchard grasses, whose mean values were 8.16%, 5.73%, 34.48%, 33.47%, 38.64%, and 5.95, respectively. All Trichoderma treatments effectively reduced the values of neutral detergent fiber and acid detergent fiber of the Orchard grasses by 7.11% and 8.04%, respectively. The 5 Trichoderma strains could substantially improve the nutritional quality of Orchard grass. Strain M1 showed the most desired effects. In a later test, M1 was identified as Trichoderma harzianum.
Effect of arbuscular mycorrhizal fungi on ecological stoichiometry characteristics of alfalfa under different water conditions
Li-xiang Guo, Jie-yu Yang, Ming-xiu Long, Wen-xue Ma, Jia-ming Yue, Jie Liu, Lin Zang, Tian-ming Hu, Shu-bin He
2018, 12(2): 398-406. doi: 10.11829/j.issn.1001-0629.2017-0015
[Abstract](720) [FullText HTML] (66) [PDF 586KB](96)
To evaluate the effect of arbuscular mycorrhizal fungi (AMF) on element contents and ecological stoichiometry of alfalfa (Medicago sativa) under drought and well-watered conditions, alfalfa plants inoculated with AMF (Glomus versiforme, M), rhizobia (Sinorhizobium meliloti, R), dual inoculation (RM), or no inoculations (CK) were evaluated in a pot experiment under controlled conditions. Organic carbon (C), nitrogen (N), phosphorus (P), and potassium (K) of plant leaves and roots were measured and ecological stoichiometric characteristics were calculated. The results showed that drought reduced the biomass of alfalfa and decreased the contents of C, N, and K in leaves and N, P, and K in roots. The M, R, and RM treatments improved the biomass of alfalfa and the contents of C, N, P, and K in leaves, but decreased the contents of N, P, and K in roots under drought. The response of C/N to water stress was not consistent, but drought improved N/P and C/P of alfalfa in leaves and roots. However, the M treatment increased C/N, N/P, and C/P of alfalfa in leaves and roots under drought condition. With different metabolic characteristics, alfalfa leaves and roots exhibited varied responses to AMF and different water availabilities. Moreover, there was no general synergistic effect of dual inoculation with AMF and rhizobia on any parameter, except for the biomass and the contents of N, P, and K in leaves. All these results contribute to clarify the mechanism between consumption of C and transfer of N and P nutrition in symbiosis.
Release characteristics and planting effects of promoted-release mixed phosphate and magnesium substrates
Jun-tao Zhang, Shao-ping Ye, Zong-wen Liao
2018, 12(2): 407-414. doi: 10.11829/j.issn.1001-0629.2017-0433
[Abstract](883) [FullText HTML] (53) [PDF 553KB](64)
Four promoted-release materials (W, Y, QW, and FS) were chosen to activate the mixture of phosphate rock and calcined magnesium oxide. Type Ⅰ and type Ⅱ mixtures of promoted-release phosphate rock and calcined magnesium oxide were added to 3% and 5% promoted-release materials, respectively. Next, promoted-release mixed phosphate and magnesium substrates for herbaceous flowers were prepared, whereas a leaching experiment and a pot experiment were conducted to study the release characteristics of water-soluble P and Mg and their effects on growth and flowering of Torenia fournieri and Catharanthus roseus. The results were summarized as follows: 1) As compared with the substrate without adding any promoted-release materials, the water-soluble P contents of promoted-release P-Mg substrates added with W, Y, QW, and FS were significantly increased by 15.42%~27.10% (P<0.05), whereas the water-soluble Mg content in treatments added with W, Y, QW, and FS showed no significant differences (P>0.05). 2) Promoted-release P-Mg substrates added with W I increased the number of flowers of T. fournieri and the crown diameter, branch number, and above-ground biomass of C. roseus; substrates added with FS-Ⅱ promoted the accumulation of above-ground biomass of T. fournieri, but adding Y-Ⅰ showed no positive effects on the growth of T. fournieri or C. roseus. Generally, promoted-release W-Ⅰ and FS-Ⅱ showed positive effects on substrates of herbaceous flowers and the appropriate addition ratios were 3.09 and 3.16 kg·m-3, respectively.
Effect of nitrogen fertilizer on switchgrass yield, N-use efficiency and residual nitrate nitrogen in Kubuqi Sandland soil
Meng Tao, De-rong Su, Shi-hai Lyu, Tie-mei Wang, Jun-han Chen
2018, 12(2): 415-422. doi: 10.11829/j.issn.1001-0629.2017-0232
[Abstract](660) [FullText HTML] (44) [PDF 574KB](72)
In order to improve the ecological environment of Kubuqi sandland and realize the effective combination of ecological and economic benefits, the warm-season herbaceous bioenergy plant switchgrass (Panicum virgatum) was introduced to Kubuqi sandland. Switchgrass BL-1 was used as the experimental material to study the effect of ammonium sulfate and urea on the yield and nitrogen-use efficiency of this species, and the distribution and accumulation of soil nitrate nitrogen in the 0-40 cm soil layer. The study used a completely randomized block design. Nitrogen fertilization was carried out with four treatments of nitrogen application rate (0, 75, 150, and 225 kg·ha-1) and three duplicates for each treatment. Urea and ammonium sulfate were applied directly to the experimental plots at the seedling stage, tillering stage, and jointing stage, with amount equivalent to 1/5, 2/5, and 2/5 of nitrogen application rate, respectively. The yield of switchgrass and the content of soil nitrate nitrogen were measured at the early flowering stage. The results showed that the application of both urea and ammonium sulfate could significantly increase the yield of switchgrass (P<0.05). The yield, nitrogen uptake, and nitrogen-use efficiency of switchgrass fertilize with ammonium sulfate increased the increase in nitrogen application rate, which first increased and then decreased when urea was applied, and the maximum was at the nitrogen application rate of 150 kg·ha-1. The nitrate nitrogen was mainly distributed at 10-20 cm soil layer and the accumulation of nitrate N increased with the increase of nitrogen application rate in the 0-40 cm soil layer.
Effect of climate change on the phenological phase of herbs in meadow grassland of Tongliao City, Inner Mongolia
Ya-min Gao
2018, 12(2): 423-433. doi: 10.11829/j.issn.1001-0629.2017-0265
[Abstract](946) [FullText HTML] (99) [PDF 641KB](99)
Plant phenology can directly reflect the effects of climate change, and it has become the focus of global climate change research. We compiled the meteorological data from 1981 to 2016 and the observational data of phenophases of four main herbs, Leymus chinensis, Agropyron cristatum, Potentilla chinensis, and Plantago asiatica from the Enkhbayar animal husbandry meteorological experiment station of Tongliao City, Inner Mongolia. The purpose of this research is to elucidate the effects of climate change on germination stage, withering stage, and the growing-season length for herbs. The results showed that the average air temperature had increased 0.35 ℃·10 a-1 (P<0.01) and precipitation had decreased 22.73 mm·10 a-1, and the climate was getting warmer and drier. The herb germination stage had been postponed 1.16~7.60 d·10 a-1, but the reasons were different with different herbs. The germination stages of L. chinensis and P. asiatica were mainly affected by the cumulative precipitation reduction from February to March, and the germination stages of A. cristatum and P. chinensis were affected by the cumulative precipitation reduction from February to April and March to April, respectively. The withering stage of herbs had different trends. The delay of the withering stage of L. chinensis and A. cristatum were mainly affected by precipitation in summer and early autumn. The advance in the withering stage of P. chinensis was mainly affected by precipitation and sunshine in summer and early autumn. The withering stage of P. asiatica was delayed mainly by average temperatures in summer and early autumn. The length of the growing season was mainly influenced by air temperature and precipitation. Our research demonstrated that the coming climate change will shorten the growing season of L. chinensis, A. cristatum and P. chinensis, due to the air temperature significantly increasing and precipitation decreasing in summer and the growing season; however, the increasing air temperature will extend the growing season of P. asiatica, due to its sensitively to temperature.
Dosage-dependent effects of Eupatorium adenophorum on Saanen goat blood levels and the histopathology of several organs
Jie Fu, Yan-chun Hu, Wei-hong Chen, Jia-hua Weng, Li-wen Hu, Zhen Shi, Ya-jun He, Quan Mo, Ya Wang, Zhi-hua Ren, Guang-neng Peng, Zhi-cai Zuo, Jun-liang Deng
2018, 12(2): 434-440. doi: 10.11829/j.issn.1001-0629.2017-0214
[Abstract](1072) [FullText HTML] (48) [PDF 1264KB](86)
The present study investigated the effects of different dosages of Eupatorium adenophorum to the diet on routine blood levels and the histopathology of the liver, kidney, and spleen in Saanen goats. Based on the random assortment principle, 16 healthy, five- to six-month-old Saanen goats were divided into four groups: control group (no E. adenophorum in the diet) and trial groups Ⅰ, Ⅱ, and Ⅲ (with 40%, 60%, and 80% E. adenophorum in the diet, respectively). The experiment lasted three months. A routine blood examination was performed every two weeks. The goats were slaughtered at the end of the experiment to observe pathological changes in the liver, kidney, and spleen. The results showed that the white blood cell(WBC) and neutrophil(NEUT) of each trial group was significantly higher (P<0.05) than that of the control group, and very significantly higher (P<0.01) at the end of the experiment. However, the lymphocyte(LY) and hemoglobin(HGB) were significantly lower than that of the control group (P<0.01). The changes in the pathology of each trial group showed swelling of the liver and spleen. The liver cells showed congestion, and vacuolar and fatty degeneration. There was hyperemia, necrosis, granular, and vacuolar degeneration in the kidney tissues. In conclusion, E. adenophorum not only causes different levels of liver and kidney damage, but also leads to a significant effect on Saanen goat blood levels over time.
Lipopolysaccharide-induced effects of tricin on inflammatory and lacto-protein gene expression in bovine mammary epithelial cells
Jin-shun Zhan, Kang Zhan, Xiao-lian Chen, Jun-hong Huo, Guo-qi Zhao
2018, 12(2): 441-448. doi: 10.11829/j.issn.1001-0629.2017-0184
[Abstract](683) [FullText HTML] (40) [PDF 535KB](97)
The aim of this study was to examine the lipopolysaccharide (LPS)-induced effects of tricin on inflammatory and lacto-protein gene expression in bovine mammary epithelial cells (BMECs). The BMECs were divided into four treatment groups. The BMECs were cultured in the medium without LPS(L) and tricin(T). The BMECs in groups L and L+T were treated with 1 μg·mL-1 of LPS without tricin, or with 10 μg·mL-1 of tricin, respectively. The BMECs in group T were cultured in the medium with 10 μg·mL-1 tricin. The results showed that the viability of cells was reduced significantly in the L treatment group (P<0.05), whereas cell viability was increased significantly in the T treatment group (P<0.01). The activity of superoxide dismutase(SOD) in the T treatment group was significantly higher than that of the L treatment group (P<0.01), but the contents of NO and malondialdehyde(MDA) showed the opposite results. The relative expression of IL-1β, IL-6, TNF-α, TLR2, TLR4, and MyD88 was elevated by LPS (P<0.01), whereas tricin supplementation reduced the relative expression of IL-1β, TNF-α, TLR2, and TLR4 in cells induced by LPS (P<0.01). The relative expression of JAK2, STAT5, mTOR, 4EBP1, and S6K1 in the T treatment group increased significantly (P<0.01), but the relative expression of CAT1 decreased significantly (P<0.01). LPS significantly reduced the relative expression of CAT1, LAT1, STAT5, mTOR, and 4EBP1 (P<0.01 or P<0.05), whereas tricin supplementation significantly increased the relative expression of STAT5 in cells induced by LPS (P<0.01). In conclusion, tricin increased the viability of BMECs and promoted lacto-protein gene expression in cells cultured in a medium without LPS. LPS elevated inflammatory gene expression and inhibited lacto-protein gene expression in BMECs. Tricin inhibited inflammatory gene expression; however, it did not improve lacto-protein gene expression in BMECs inhibited by LPS.
Research progress of low starch diet for dairy cow
Zhi-lan Wang, Fa-di Li, Fei Li
2018, 12(2): 449-455. doi: 10.11829/j.issn.1001-0629.2017-0233
[Abstract](814) [FullText HTML] (52) [PDF 499KB](105)
Feeding dairy cows on low-starch diets can satisfy their energy requirement during lactation, and protect the rumen health of dairy cows and avoid rumen acidosis, as well. In general, the cows were fed on low-starch diets, containing digestible forage fiber, neutral detergent-soluble fiber, and soluble sugar. Feeding on low-starch diets can effectively reduce volatile fatty acid production, inhibit decrease in ruminal pH, and promote feed intake and nutrient digestion in dairy cows. Additionally, it can improve milk quality. This study showed how to formulate the low-starch diet, influencing rumen fermentation parameters and production performance; it was necessary to feed dairy cows on the low-starch diet. In future, it would be important to investigate the optimal proportion and effect of mixing, using low-starch materials as substitutes of cereal grains, to complete the process of low-starch diet preparation for dairy cows.
Effect of different additives on the silage quality of Longdong alfalfa
Chun-sheng Xue, Rui-sheng Liu, Jian-feng Xu, Jin-lin Zhang
2018, 12(2): 456-462. doi: 10.11829/j.issn.1001-0629.2017-0292
[Abstract](697) [FullText HTML] (43) [PDF 518KB](96)
Biological additives play important roles in improving the activity of bacteria and enzymes during fermentation, thereby improving the digestibility and quality of silage. In this study, the effects of various additives (formic acid, sucrose, EM bacteria, and cellulase) on the silage quality of the alfalfa cultivar Longdong were investigated by using the first crop of alfalfa as the raw material. The results showed that the sensory evaluation scores of alfalfa silages in the four additive treatment groups were higher than that of the silage in the control group. pH values, acetic acid, and ammonia nitrogen/total nitrogen contents of the silages in the four additive groups were significantly lower than those in the control group silage, and lactic acid content was significantly higher in the treatment group silages than that in the control group silage (P<0.05). No butyric acid and propionic acid were detected. The contents of crude protein in the silages of the four additive groups were significantly higher than that in the control group, and the content of acid detergent fiber was significantly lower in all additive group silages than that in the control group silage (P<0.05). The neutral detergent fiber contents of the silages in the sucrose, EM bacteria, and cellulase groups were significantly lower than those of the silages in the formic acid and control groups (P<0.05). There were no significant differences in the crude ash contents of silages among all the groups (P<0.05). The aerobic stability of silages in the four additive groups was significantly higher than that of the silage in the control group (P<0.05). The results suggested that the four additives can improve the sensory quality, fermentation quality, and nutrient composition of silage produced from the alfalfa cultivar Longdong, and prolong its aerobic stability. The effects of the four kinds of additives on the growth of alfalfa were optimized by adding cellulase.