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2017 Vol.34(12)

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Ecosystem carbon exchange of an alpine meadow under simulated gradient warming in the Tibetan Plateau, China
Xiao-dong Geng, Xuri
2017, 11(12): 2407-2415. doi: 10.11829/j.issn.1001-0629.2017-0090
[Abstract](1197) [FullText HTML] (156) [PDF 636KB](422)
Alpine meadow is one of the primary alpine grassland ecosystems in the Tibetan Plateau region, which is sensitive to climatic changes, including global warming. Therefore, it is crucial to investigate how the ecosystem carbon exchange of the alpine meadow varies with increasing temperature. In the present study, we conducted a five-level warming experiment (T0, no warming; T1-T4 represent the different warming treatments) and the ecosystem carbon exchange was measured using open-top chambers (OTCs) and infrared analyzer, respectively, over three consecutive growing seasons. Our results showed that: 1) compared to the control, warming enhanced the temperature of 5 cm soil layer by 1.73 (T1), 1.83 (T2), 3.03 (T3) and 3.53 ℃ (T4), respectively for four warming treatments; but soil moisture changed in a non-linear fashion. 2) The negative values of the net ecosystem carbon exchange (NEE) indicated that the alpine meadow acted as a carbon sink. 3) Warming that less than 2 ℃ substantially improved the gross ecosystem productivity (GEP), but had no significant effect on ecosystem respiration (ER), resulting in a net increase in NEE value. In other words, moderate warming could stimulate carbon sequestration in the alpine meadows, but in a warmer scenario (e.g. temperature increased by more than 3 ℃), carbon sequestration would be restricted due to the decrease in GEP. These findings suggest that the alpine meadow will uptake more/less CO2 in moderate/outranged warming scenarios, accordingly.
The agricultural drought remote sensing monitoring methods and prospects based on different underlying surface conditions
Yao-yao Zhang, Xia Cui, Qing-jie Song, Gao-feng Zhu
2017, 11(12): 2416-2427. doi: 10.11829/j.issn.1001-0629.2017-0080
[Abstract](1081) [FullText HTML] (147) [PDF 673KB](202)
Drought is one of the major natural disasters for China’s agricultural industry. By selecting asuitable monitoring index based on land surface conditionsduring different growth periods of crops, remote sensing monitoring ofagricultural drought can timely and effectively evaluate the effect of drought on crop growth and provide animportant source for decisions to be made by thegovernment. The present study summarized the widely used agricultural remote sensing monitoring methods, which were based on different land surface conditions. These methods weredivided into three classes: monitoring methods based on bare surface or low vegetation cover, monitoring methods based on high vegetation cover, and integrated monitoring methods based on all land cover conditions. In addition, the future development directions of agricultural remote sensing drought monitoring werestudied and discussed, and included: 1) monitoring data beingtransformedfrom asingle data source to multi-source data; 2)monitoring indicatorschangingfrom single meteorological monitoring indicators to acomprehensive monitoring index, which integratesmeteorological, satellite remote sensing with crop physiological and physical characteristics; 3) the 3S technology integration and data sharing.
Vertical distribution characteristics of Miscanthus sinensis roots and its relationship to soil nutrients in the Wugong Mountains
Xiao-juan Hou, Zhi Li, Cheng Cui, Kai Li, Fei Yu, Ying-dan Yuan, Xiao-min Guo, De-kui Niu
2017, 11(12): 2428-2436. doi: 10.11829/j.issn.1001-0629.2017-0135
[Abstract](919) [FullText HTML] (112) [PDF 603KB](191)
Roots are structures that connect vegetation to the soil. Studies of the relationship between roots and soil help understand the biochemical cycle of nutrient elements and provides a theoretical basis for vegetation restoration. In the present study, soil nutrients were studied by normal analysis methods using Miscanthus sinensis Anderss as a model plant from the Wugong Mountains. Root parameters were determined by a root scanner. Correlation analysis and regression analysis were performed to examine the relationship between soil and roots. The results demonstrated that root parameters decreased with an increase in soil depth. Approximately 80% of the roots were distributed in the 0 to 16 cm soil layer. Power functions were fitted between different soil layers and root parameters (biomass density, root length density, and root surface area density), and were y=238x-1.555 9 (R2=0.891 14),y=169.9x-0.882 05(R2=0.408 36) and y=22.397x-0.926 14(R2=0.364 57), respectively. The content of soil organic matter, total N, total P, available P, and available K decreased with depth of soil in the 0 to 40 cm soil layer whereas the content of total K and available N fluctuated slightly. Correlations between soil nutrients and root parameters differed among nutrients, whereas organic matter, total N, and total K correlated positively with root parameters (P<0.05). Therefore, fertilizing effectively in the top soil surface layer is beneficial for root development and nutrient uptake.
Soil moisture characteristics of eight types of shelter forest in the Kubuqi desert
Meng-he Gu, Ze-hui Xie, Chun-hui Wang, Li-hua Zhou
2017, 11(12): 2437-2444. doi: 10.11829/j.issn.1001-0629.2016-0615
[Abstract](782) [FullText HTML] (72) [PDF 521KB](158)
In this paper, we analyzed the variation characteristics and variable coefficient of soil moisture among eight kinds of travel highway shelter forest at Qixinghu Lakes in the Kubuqi desert by field investigation, to study the soil moisture characteristics and soil moisture variability of shelter forest in the Kubuqi area. The results showed that the soil moisture, measured in five soil layers (0-20, 20-40, 40-60, 60-80, 80-100 cm depth), gradually increased with soil depth. The soil moisture coefficients of variation were 0.70, 0.94, 0.92, 0.94, and 0.90, respectively, and increased gradually with soil depth. From big to small, the soil moisture in the eight types of shelter forest were, respectively: Salix matsudana+Populus popular’s (9.31%), S. matsudana (8.93%), Elaeagnus angustifolia+S. psammophila (5.69%), E. angustifolia (3.31%), Populus spp.(2.12%), Populus spp.+ Hedysarum laeve (1.90%), Caragana korshinskii (1.60%), and H. laeve (1.02%). According to the soil moisture coefficients of variation, the eight kinds shelter forest were divided into three groups: Caragana korshinskii (0.08) was weak variation; H. laeve (0.11), Populus spp. (0.11), Populus spp.+ H. laeve (0.36), and E. angustifolia+S. psammophila (0.39) were low variation; S. matsudana (0.64), S. matsudana+P. popular’s (0.67), and E. angustifolia (0.79) were medium variation. We find that S. matsudana+P. popular’s, S. matsudana, and E. angustifolia+S. psammophila were the most suitable choices to conserve soil water. E. angustifoli and C. korshinskii were the next. H. leave, Populus spp. and H. laeve+Populus spp. were not satisfactory choice.
Physiological response of four wild Poa to soil pH
Yan-feng Tian, Xiao-ming Bai, Xiao-jun Zhang, Zheng-qiang Wei, Run-juan
Xu-yang Niu
2017, 11(12): 2445-2453. doi: 10.11829/j.issn.1001-0629.2017-0084
[Abstract](859) [FullText HTML] (40) [PDF 1008KB](214)
To investigate the mechanism by which soil pH affects physiological characteristics of wild bluegrass and to determine the optimum growth pH for wild bluegrass, the physiological indicators of four wild bluegrasses collected in Gansu Province were determined under 8 pH treatments. The results showed that in the range of 3 to 10, with an increase in pH, relative membrane permeability, free proline(Pro), soluble sugar(SS), and MDA and POD activity of the four wild bluegrasses showed first a decrease and then an increase, whereas the soluble protein content(SP) and activity of superoxide dismutase(SOD) and catalase(CAT) showed an opposite trend. The optimal pH values, in which damage to the bluegrass was minimal, was 7 for Kentucky bluegrass, small medicine bluegrass, and annual bluegrass, and 6 for hard bluegrass. These results provide information for the maintenance and management of Kentucky bluegrass lawns, as well as the introduction and domestication of wild Kentucky bluegrass.
Molecular identification and biological activity of three Bacillus strains isolated from an alpine meadow rhizosphere in Qinghai Province
Xiao-hui Wu, Yong-li Xie, D′Ovidio Renato, Ying Zhang, Guang-xin
Zong-xiu Xin, Masci Stefania
2017, 11(12): 2454-2463. doi: 10.11829/j.issn.1001-0629.2017-0055
[Abstract](934) [FullText HTML] (74) [PDF 1861KB](242)
For the purpose of restoring degraded vegetation and improving the aboveground biomass of grassland, the biological activity of three strains of Bacillus spp. bio-control agents were isolated and screened. Three strains isolated from an alpine meadow (Kobresia pygmaea) rhizosphere in Huangnan Autonomous Prefecture, Qinghai Province, were identified by 16S rDNA and gyrB partial sequence analyses. Antagonistic activity of strains to pathogenic fungi were determined by the flat confrontation test, and the growth-promoting activities of strains were checked by soaking plant seeds in strain suspension (106 cfu·mL-1 of cell concentration). In addition, cellulose-degrading activities of strains were checked with carboxymethylcellulose (CMC) plate test, Gram staining, and 3,5-dinitrosalicylic acid (DNS) methods; moreover, cellulase coding genes of the strains were amplified and analyzed. The results showed that the isolate of HNC3 was identified as Bacillus pumilus, and isolates of HNC8 and HNC11 were identified as B. thuringiensis. The three strains presented distinct antagonistic activity to Fusarium graminearum S and Fusarium oxysporum (inhibition zone diameter ≥ 11 mm). Furthermore, the strains showed obvious germination and growth-promoting activity after soaking the wheat seeds in Bacillus suspension. The effect of the isolate of HNC3 on the growth of wheat seedlings was significant; the rate of bud and root length growth increased by 55% and 80%, respectively. The cellulase activity of the isolate of HNC3 reached 367.51 U·mL-1, and its cellulase coding genes could be amplified including lichenase (blg1S), mannosidase (ManSig), and xylanase (xynD, xynB). The three Bacillus strains used as bio-control agents all showed antagonistic, plant growth-promoting, and cellulose-degrading activities, which present future research opportunities into the potential of their application in the recovery of plateau grassland vegetation, as well as in the field of ecological animal husbandry.
Floristic characteristics of woody plants in the Beita Mountain of Xinjiang
Shan-shan Li, Shu-ping Yang, Ping Yan, Shan-shan Ren, Wen-bin Xu
2017, 11(12): 2464-2469. doi: 10.11829/j.issn.1001-0629.2017-0060
[Abstract](870) [FullText HTML] (51) [PDF 426KB](167)
This study aimed to collect and identify the flora of Beita Mountain in Xinjiang. The research showed that there are 71 species of woody plants belonging to 41 genera in 21 families in this area, including 6 species of gymno-species belonging to 3 genera in 3 families and 65 species of angiosperms belonging to 38 genera in 18 families. Among the families, 7 families were each represented by a single species, while 11 families were each represented by 2~9 species, and the family Chenopodiaceae was represented by 15 species. Among the genera, 24 genera were each represented by a single species, while 17 genera were each represented by 2~4 species. The geographical distribution of the flora in this area is complex, exhibiting 5 distributional types and 3 subtypes at the genera level that mainly corresponded to variants of temperate floral distributions.
Diseases of Angelica sinensis and screening fungicides for controlling leaf spot disease in Minxian County of Gansu Province
Shu-zhen Chen, Xu-xia Ji, Cheng-de Yang, Yan Wang
2017, 11(12): 2470-2475. doi: 10.11829/j.issn.1001-0629.2016-0611
[Abstract](892) [FullText HTML] (66) [PDF 480KB](175)
The diseases of Angelica sinensis were surveyed in the Minxian district of Gansu Province from 2012 to 2016 and fungicide for controlling leaf spot diseases were tested. In total, 11 diseases have been identified in this region. These include nematode disease (Ditylenchus destructor), root rot (Fusarium sp.), brown spot (Septoria sp.), powdery mildew (Erysiphe heraclei), gray mold (Botrytis sp.), anthracnose disease (Colletotrichum dematium), sclerotinia (Sclerotinia sp.), water rot (Pseudomonas fluorescens), viral disease (ToMV), and two bacterial diseases. With regard to Angelica brown spot disease, treatment with 80% mancozeb, 10% difenoconazole, 70% thiophanate methyl, or 46.1% copper hydroxide reduced the disease index by 64.83%, 59.66%, 53.84%, and 51.56%, respectively. With regard to bacterial leaf spot disease, treatment with 46.1% copper hydroxide, 50% carbendazim, or 70% thiophanate methyl reduced the disease index by 74.20%, 59.67%, and 58.07%, respectively. These results provide the basis for the control of Angelica diseases in Minxian County of Gansu Province.
Identifying and applying the symbolic elements of golfers’ place attachment
Yong Luo
2017, 11(12): 2476-2484. doi: 10.11829/j.issn.1001-0629.2017-0303
[Abstract](920) [FullText HTML] (41) [PDF 618KB](174)
In this study, the symbolic elements of golfers’ place attachment are identified and applied using the Zaltman metaphor elicitation technique. The results show that there are 22 kinds of symbolic elements related to place attachment, which can be divided into five categories: style, geography, participation, reception, and culture. These elements elicit feelings of “friendship”, “health”, “happiness”, “high quality”, and “beautiful scenery” to golfers. Golf course operators should make full use of the meaning of these symbolic elements, and focus on building the golf course infrastructure, landscape, reception service, and culture. They should actively explore the coupling values of the structure, improve the interaction between players and the course, and actively create a golf player to avoid the interruption or shifting of local attachment.
Effects of three salt stresses on growth, physiology, and biochemistry of Cirsium japonicum
Cong-ying Long, Hui-ming Deng, Ming-jie Su, Shi-zhen Cai, Xiao-ming Xu
2017, 11(12): 2484-2492. doi: 10.11829/j.issn.1001-0629.2017-0102
[Abstract](851) [FullText HTML] (61) [PDF 616KB](228)
The effects of three salt stresses (NaCl, Na2SO4, Na2CO3) at different concentrations (0.1%, 0.2%, 0.3%, 0.4%, 0.5%, and 0.6%) on seedling height, relative water content, malondialdehyde (MDA), antioxidase activity (POD, SOD, and CAT), and osmotic regulation substances (soluble sugar and free proline contents) in leaves of Cirsium japonicum were studied in pot experiments. The results showed that seedling heights and relative water contents were reduced compared to the control (CK) in all salt stress treatments except 0.1% NaCl treatment and that the effects increased with increasing salt concentrations. Seedling heights in the 0.3% NaCl, 0.4% Na2SO4, and 0.1% Na2CO3 treatments were 62.15%, 58.00%, and 45.77%, respectively, of the CK level; seedlings in the 0.5% Na2CO3 treatment died. Increasing salt concentrations and length of treatment caused an increase in MDA contents in leaves. The POD, SOD and CAT activities of leaves varied with changes in salt concentration and treatment time. A significant activity threshold was observed for POD on the fifth day of the 0.3% NaCl treatment, 0.3% Na2SO4 treatment, and 0.4% Na2CO3 treatment. Significant activity of SOD was first detected on the third day with 0.3% NaCl treatment, on the first day of 0.5% Na2SO4 treatment, and on the third day with 0.4% Na2CO3 treatment. Significant CAT activity was first observed on the third day with 0.3% NaCl treatment, 0.2% Na2SO4 treatment, and 0.1% Na2CO3 treatment. At the same process times, the proline contents increased at first and then decreased in the NaCl treatments; in the Na2SO4 and Na2CO3 treatments, the soluble sugar content increased gradually with the increase in salt concentration. In conclusion, C. japonicum shows some tolerance to NaCl, Na2SO4, and Na2CO3 stress, and can survive and grow under conditions of less than 0.3% NaCl, 0.4% Na2SO4, or 0.1% Na2CO3.
Functional traits of major herbaceous plants in the hydro-fluctuation belt of the Three Gorges Reservoir
Ting Gao, Miao Chen, Cheng-qiang Dang, Hui-min Huang, Rong Dong, Jian-ping Tao
2017, 11(12): 2493-2503. doi: 10.11829/j.issn.1001-0629.2017-0072
[Abstract](1756) [FullText HTML] (395) [PDF 965KB](213)
The environmental heterogeneity of the hydro-fluctuation belt in the Three Gorges Reservoir is illustrated by the fact that each elevation corresponds to a different time and depth of water submergence. We analyzed seven plant functional traits in 37 major herbaceous species from three sample sites in the reservoir hydro-fluctuation belt. We then divided the plant species into different groups (including different life forms and different plant families) and analyzed variations in their functional traits. To determine growth and resource utilization adaptability of plants located in different elevation belts, we analyzed the plant functional traits and trait correlations at different elevations (corresponding to different water environments). We identified four particular traits in the results. 1) Leaf dry matter content (LDMC) and fine root tissue density (FRTD) of perennials were significantly higher than those of annuals and biennials (PPPP<0.05). 4) There was convergence in plant traits among different elevation belts. The study showed that different herbaceous plant groups generate various trait combinations to adapt to the environment. Plants growing in lower elevation habitats have a low investment and quick recovery growth strategy, and vice versa. The plant trait correlation convergence among different elevation habitats implies a convergent adaptation of herbaceous plants in the hydro-fluctuation belts of the Three Gorges Reservoir.
Estimation of biomass based on HJ-HSI data in Seriphidium transiliense desert grassland
Xiu-hong Wei, Gui-li Jin, Yan-min Fan, Sha-zhou An, Xi-wen Zhu, Hui-ning Wang
2017, 11(12): 2504-2511. doi: 10.11829/j.issn.1001-0629.2017-0059
[Abstract](799) [FullText HTML] (85) [PDF 648KB](150)
The aboveground biomass of degraded Seriphidium transiliense desert grassland areas under different utilisations (N: fenced area, W1: unfenced and heavily degraded area, and W2: unfenced and moderately degraded area) were estimated using spectral variables and band variables selected from the spectral reflectance of a HJ-HSI satellite image taken in the same period. The results showed that: 1) The spectral reflectance of the grassland communities differed among plots during different seasons, and their reflectance was ordered as W2 > N > W1 in spring, W2 > W1 > N in summer, and W1 > W2 > N in autumn; 2) HJ-HSI can be used to estimate the aboveground biomass of this kind of grassland, and the results of the estimation models vary among different community types and seasons. The estimates obtained by the models for the spring, summer, and autumn were as follows: DVI, NDVI, 620.225-627.895 nm reflectance average construction in plot N; Rn, 656.305 and 776.8199 nm reflectance normalised values, MSAVI construction in W1; 652.09 and 732.01 nm reflectance normalised values, Rr, 584.52-598.295 nm average construction in plot W2.
Effects of different planting densities and fertilization levels on yield and quality of sweet sorghum grown under covering film cultivation in the dry land of Qinghai
Hui-ying Yan, Chun-xi Li, Pei-lin Ye, De-hu Mao, Rong Li
2017, 11(12): 2512-2520. doi: 10.11829/j.issn.1001-0629.2017-0331
[Abstract](954) [FullText HTML] (103) [PDF 666KB](172)
In this experiment, Jitian 5 and Jiutianza 3 were used as materials in an experimental study on the effects of different planting densities. Linespacing×plant spacing: (40 cm×40 cm, 40 cm×30 cm, 40 cm×20 cm) and amount of urea (0, 150, 225 kg·ha-1) in the topdressing on the yield and quality of sweet sorghum were studied at an altitude of 2 040 m on dry land in Qinghai by covering film cultivation. The results showed that the fresh and hay yields of two cultivars were the highest at the spacing of 40 cm × 20 cm (120 000 hole·ha-1). The yield of fresh grass was 99.75 and 108.17 t·ha-1.The hay yieldswere 17.89 and 22.58 t·ha-1, respectively. The yield was higher and quality was better at 150 kg·ha-1 urea at the jointing stage. The crude protein of the two cultivars was 5.47% and 4.80%, crude fat was 5.67 and 7.57 g·kg-1, acidic detergent fiber was low, and comprehensive performance was good. In conclusion, a planting density of 120 000 hole·ha-1 and topdressing urea of 150.0 kg·ha-1 at the jointing stage are most suitable for sweet sorghum in the Qinghai dry land
Sowing a mixture of alfalfa modulates the population density of alfalfa pests
Jian-hua Ma, Zi-hua Zhao, Rong Zhang
2017, 11(12): 2521-2527. doi: 10.11829/j.issn.1001-0629.2017-0018
[Abstract](836) [FullText HTML] (76) [PDF 961KB](160)
Alfalfa is an important forage crop, referred to as the “king of forage”. With the development of the alfalfa industry, pest damage in alfalfa fields had increased rapidly. Therefore, ecologically based pest management strategies have gained importance in habitat management. In the present study, six varieties of alfalfa were used in 18 treatments sowing either mixture or monoculture, which was aimed to determine the effects of mixture sowing of alfalfa on pest and natural enemies. The results showed that mixture sowing decreased the population density of aphids and enhanced the population density of lady beetles. The minimum population density in mixture sowing alfalfa was 149 individuals per straw, whereas the maximum population density in monoculture alfalfa was 823 individuals per straw. However, mixture sowing had no significant effects on thrips. These results provide important experiment data to support the development of the alfalfa industry and suggest planting patterns for integrated pest management.
Influence of grazing and arbuscular mycorrhiza fungal infections on vegetative growth and powdery mildew incidence in Elymus sibiricus grown in the eastern margin of the Tibetan Plateau in summer
Fang Li, Feng Zhang, Yan-e Guo, Ping Gao, Ting-yu Duan
2017, 11(12): 2528-2537. doi: 10.11829/j.issn.1001-0629.2016-0618
[Abstract](882) [FullText HTML] (54) [PDF 706KB](170)
We established a greenhouse experiment to study the influence of arbuscular mycorrhiza (AM) fungal infections on plant growth and powdery mildew incidence in the grass species Elymus sibiricus. Soil was collected from Gansu Maqu alpine grassland and used as follows: no treatment, sterilized to eliminate all microorganisms, sterilized and microorganisms returned except for AM fungi, sterilized and inoculated with a mix of Rhizophagus intraradices and Claroideoglomus etunicatum. E. sibiricus was grown on each of the treated soils and subjected to light grazing (LG), moderate grazing (MG), or heavy grazing (HG). Our analyses showed that growth and powdery mildew incidence in E. sibiricus was influenced by grazing and AM fungal colonization. Powdery mildew incidence varied among grazing intensities and soil treatments. Compared with the intensity in LG, in MG and HG, E. sibiricus had a lower powdery mildew incidence and higher total dry weight, total P content, and photosynthetic rate. The rate of powdery mildew was the highest (59.83%) in plants on soil without any treatment and the lowest (44.73%) in plants on sterilized soil. The rate of E. sibiricus powdery mildew disease decreased 13.15% and total plant dry weight increased by 56.46% after inoculation with AM fungi compared with no treatment. Grazing intensities and soil treatments had interaction effects on total P content, chlorophyll content, and PPO activity.
Effects of Bupleurum extract on the performance and blood metabolism in heat-stressed dairy cows
2017, 11(12): 2538-2545. doi: 10.11829/j.issn.1001-0629.2017-0495
[Abstract](712) [FullText HTML] (27) [PDF 675KB](169)
This experiment was conducted to evaluate the effects of Bupleurum extract (BE) on the performance and blood metabolism in dairy cows under heat stress. Forty-eight lactating Holstein cows were randomly assigned to one of four 2.5 treatments based on their dry matter intake (DMI), milk yield, and parity. Treatments consisted of 0, 0.5, 2.5 and 5.0 g·kg-1 BE, supplemented over a trial period of 10 weeks. Supplementation of BE affected the rectal temperature, DMI, milk yield, milk protein yield, and somatic cell score of the test subjects in a quadratic manner, and the peak values were reached at a dose of 0.5 g·kg-1 BE. Milk urea nitrogen concentration, milk fat, total solid content, and blood urea nitrogen, albumin, total cholesterol, high-density lipoprotein cholesterol, and β-hydroxybutyricacid were decreased (PPP=0.05) in cows fed 2.5 or 5.0 g·kg-1 of BE. Compared to cows fed 0 or 0.5 g·kg-1 of BE, serum total cholesterol and high-density lipoprotein cholesterol levels increased in cows fed 5.0 g·kg-1 of BE. Therefore, the appropriate supplemental BE level for heat-stressed dairy cows is 0.5 g·kg-1, and the safe dosage of BE is no more than 5.0 g·kg-1 .
Comparison of methods for detecting aflatoxins B1 and M1 in milk
Yu-fen Luo, Xiu-xiu Weng, De-fu Tang, Jian-zhong Pan, Fang Nian
2017, 11(12): 2546-2553. doi: 10.11829/j.issn.1001-0629.2017-0104
[Abstract](762) [FullText HTML] (81) [PDF 590KB](161)
Immunoaffinity column-high performance liquid chromatography (HPLC) and enzyme-linked immunosorbent assay (ELISA) methods were adopted to determine aflatoxins (AF) B1 and M1 in milk. The recovery, detection limit, and precision of these two methods were compared in this study. The results showed that, for HPLC, the detection limits of AFB1 and AFM1 were 0.02 and 0.01 μg·L-1, respectively, while for ELISA, the detection limits of AFB1 and AFM1 were 0.05 and 0.02 μg·L-1, respectively. Standard solutions of AFB1 (0.003, 0.006, 0.012, and 0.024 μg·kg-1) and AFM1 (0.005, 0.01, 0.025, and 0.05 μg·kg-1) were added into blank milk samples and the results of recovery experiments indicated that, for HPLC, the recoveries of AFB1 and AFM1 were 77.58%~82.81% and 77.51%~82.23% with relative standard deviations of 1.93% and 3.51%, respectively. For ELISA, the recoveries of AFB1 and AFM1 were 77.28%~79.11% and 75.40%~76.34% with relative standard deviations of 2.20% and 3.80%, respectively. The recovery of AFB1 did not significantly differ between the two methods (P>0.05). However, the recovery of AFM1, when the amount added was more than 0.025 μg·kg-1, was significantly higher by HPLC than by ELISA (P1, the accuracy of HPLC was better than that of ELISA.
Herdsmen livestock production and snow disaster countermeasures in the southern pastoral area of Qinghai Province
Song Gao, Ying-wen Yu, Qi-sheng Feng
2017, 11(12): 2554-2560. doi: 10.11829/j.issn.1001-0629.2016-0633
[Abstract](806) [FullText HTML] (78) [PDF 675KB](218)
The type and number, reproductive survival rate and mortality rate, slaughter number, body weight loss and herbage supplement level of livestock, greenhouse construction, income, and expenditure of typical herdsmen were investigated by the household survey method in Dari County, Maduo County and Chengduo County, in the southern pastoral area of Qinghai Province, and the benefit scheme designed for the winter and spring snow disasters was also analysed. The result showed that the number of livestock of herdsmen was 82.5~423.2 animal units (AU), the supplementary feeding level was 1.2~26.5 CNY·(a·AU)-1, and the livestock slaughter was minimal, while only 1/3 of the herdsmen have a greenhouse constructed. The income of the herdsmen was mainly from government subsidies, and the forage reserve of herdsman was low, accounting for < 5% of the total expenditure. The ability to respond to snowstorms for individual herdsman was weak. In the snow storm and moderate snow disaster years, the reproductive survival rate of livestock was 41.5%~75.9% and 65.0%~86.4%, respectively, while the livestock mortality was 13.2%~24.4% and 8.2%~12.8%, and the body weight loss was 30%~40% and 20%~30%. Basing the main problems on the livestock management of the herdsmen, we suggest enhancing the livestock slaughter rate and increasing the livestock supplement feeding in the cold season, which can reduce the livestock death loss in winter-spring snow disasters, improving the herdsmen’s ability to respond to the snowstorms.
Temporal dynamics and optimal partition of aphids in an alfalfa field
Zhao-liang Liu, Zhong-lin Yuan, Guo-feng Yang, Lan Luo
2017, 11(12): 2561-2568. doi: 10.11829/j.issn.1001-0629.2017-0088
[Abstract](705) [FullText HTML] (57) [PDF 650KB](140)
Aphids are one kind of serious insect pest in alfalfa fields. In order to clarify the spatial distribution pattern and population dynamics of alfalfa aphids in Qingdao, and provide a basis for integrated management, aphid population dynamics were analyzed in a Qingdao alfalfa field in 2013. We studied spatial distribution pattern and optimal partition using aggregation index method and optimal partition method, respectively. The results showed that the aphid population had two annual peak occurrences: late May and late October. The population demonstrated aggregate distribution when at a higher density, and the aggregation intensity decreased with an increase in population density. The population dynamics could be divided into seven periods using the optimal partition method: initial stage (before April 6); developing stage (April 14 to May 11); quick-increase stage (May 18-25); decline stage (June 1-8); secondary initial stage (June 8 to September 15); secondary developing stage (September 22 to October 2); and secondary quick-increase stage (October 7-27). We discussed the characteristics and impact factors of each stage. Alfalfa aphids in Qingdao demonstrated aggregate distribution and the population experienced two peaks. The suitable control stages are early May and early October.
EPG analysis of Acyrthosiphon pisum feeding behavior onsix alfalfa varieties with different resistances
Shu-hua Wei, Chun-jing Cao, Xiao-fang Zhu, Rong Zhang, Ying Wang
2017, 11(12): 2569-2574. doi: 10.11829/j.issn.1001-0629.2017-0383
[Abstract](891) [FullText HTML] (120) [PDF 635KB](156)
The feeding behavior of Acyrthosiphon pisum on six alfalfa varieties with different resistances, and the resistance mechanisms of these different cultivars, were examined using the electrical penetration graph (EPG) technique. The results showed that there were eight EPG waveforms of aphids feeding on alfalfa leaves, but the durations of the eight waveforms were different between the six cultivars. The resistance of alfalfa was consistent with the duration of the E1 wave, which was produced by A. pisum feeding on the phloem of the alfalfa varieties. The duration of the E1 wave was significantly different between the six different resistances of the alfalfa cultivars; the duration of the E1 wave was longer when the resistance of the alfalfa was stronger. The duration of the E1 wave on the most resistant cultivar was 36.83 min for ‘MF4020’, and the duration of E1 wave on the least resistant cultivar was 1.50 min on ‘Giant pastoral 37CR’.The resistance mechanisms of the different alfalfa cultivars to aphids are further illustrated by electrophysiology in research; it could provide the scientific basis for the breeding of alfalfa varieties with increased resistance to aphids
Actual research and application of the silage lactic acid bacteria additives
Hong-mei Zhang, Zhen Duan, Xia Li, Jian-yong Liang, Jian-hua Zhang, Xiao-kang Li
2017, 11(12): 2575-2583. doi: 10.11829/j.issn.1001-0629.2016-0564
[Abstract](949) [FullText HTML] (71) [PDF 594KB](198)
The addition of lactic acid bacteria (LAB) plays an significant role in improving the quality of silage. In this paper, in order to define the research and application of LAB additives globally, the fermentation characteristics of LAB in silage and the study on screening and application is summarized. At present, the research has clarified the fermentation principle and the fermentation phases. The research include several aspects, as follows: firstly, the three factors impacting fermentation comprise LAB itself, environmental factors, and crop characteristics; secondly, studies on LAB addition to silage mainly concentrated on screening and adding the most suitable LAB to ensile; thirdly, application methods of LAB to silage mainly include adding individually and mixed, with enzymes or other functional microbes. In future studies, LAB should been explored and screened from various ecological environments, and the research of utilization technology according to actual demand and agricultural technology of China should be strengthened.
An investigation of willingness and factors determining orchardists behavior of growing forage within the apple orchard in Qingyang, Gansu
Long-gang Wang, Cheng-fang Jiang, Xing-yuan Liu, Wen-e Zhang, Zi-kui
Jun-cheng Li, Yu-ying Shen
2017, 11(12): 2584-2590. doi: 10.11829/j.issn.1001-0629.2017-0041
[Abstract](884) [FullText HTML] (47) [PDF 510KB](171)
Planting forage grass in orchards has been widely applied in many areas of China as it is an environmentally friendly orchard management technique. Based on survey data from 172 orchardists in Qingyang of Gansu Province, this study analysed growing forage grass in orchards and the willingness of orchardists to grow grass. We used the logistic regression model to quantify the contribution of different factors related to the willingness of the orchardists. The results showed that 23.8% of the orchardists have planted forage grass and 36% plan on planting forage grass; the majority are unaware of the practice. The choice of orchard types(PPPP<0.05) showed significant impacts on the their willingness.
Empirical study of the influencing factors in grassland animal husbandry industry chain cooperative mechanism
2017, 11(12): 2591-2602. doi: 10.11829/j.issn.1001-0629.2017-0380
[Abstract](731) [FullText HTML] (46) [PDF 653KB](166)
For building and operating a grassland animal husbandry industry chain, a stable, harmonious, and effective interest linkage mechanism is a necessary precondition. Therefore, the research group conducted a questionnaire survey among the chain participants, namely, the herdsmen, cooperatives, and leading enterprises in four typical grassland animal industries from Xinjiang, Inner Mongolia, Qinghai, and Gansu. The group also analyzed the factors influencing the industry chain interest linkage mechanism through the structural equation model. There are four conclusions here. First, the behavioral aspect, logistic characteristics of the animal products, and cooperation intention have a significant positive influence on the industry chain interest linkage mechanism. Second, these characteristics also indirectly influence the benefits from affiliation to the cooperative mechanism while operation status has no impact. Third, the behavior of participants directly and indirectly affects the interest linkage among, them, while the logistic characteristics of animal products have very little influence on the operation intention. Fourth, the state of development, contractual relationships,distribution channel, and awareness of the operation expectations among the participants of the industry chain are prominent factors influencing the operation conditions, behavior, logistic characteristics of animal products, and operationintention in benefit coupling mechanisms respectively.