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2020 Vol.37(4)

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2020, (4): 602-602.
[Abstract](1381) [FullText HTML] (871) [PDF 345KB](21)
Plateau zokor mound community vegetation structure and stability in the Qinghai alpine steppes
XU Wenbing, SHI Ying, XING Yayun, ZHANG Xi, ZHENG Zhihu, LUO Qiaoyu
2020, 37(4): 603-611. doi: 10.11829/j.issn.1001-0629.2019-0328
[Abstract](24128) [FullText HTML] (1897) [PDF 880KB](162)
Eospalax baileyi is one of the most important rodents living underground in the Qinghai-Tibet Plateau. It accumulates a mound of soil on the grassland through excavation behavior, forming bare hills of different sizes with a mosaic distribution, which has some impact on the surrounding plant communities. In this study, the plant species composition and important values of biomass composition of functional groups, species diversity and community stability were quantitatively analyzed, and the convergence rule of plant community structure and stability characteristics under grazing and fencing was clarified. The results indicated that: 1) Number of plant species was very small on mounds in fenced and grazing plots, there have 17 and 11 species, respectively. Fencing was beneficial to the invasion and growth of plants on the mound. 2) The formation of the mound increased biomass (122.71 g·m–2) and the proportion of hemicryptophytes (20.77%), and decreased the proportion of geophytes (22.50%) in the surrounding plant communities, which promoted the transformation from grassland/sedge community to grass community, but had no effect on plant species diversity of the grassland community. 3) Fencing decreased the stability, while grazing increased the stability of grassland communities around mound and non-mound areas. 4) The increase in plant biomass in the mound meadow could partly compensate for the loss of biomass in the nude mound, with 35.28% and 57.93% loss in biomass in the nude mound in fencing and grazing plots, respectively.
Effects of microbial inoculant on Seriphidium transiliense seed germination characteristics
TANG Lisi, SUN Zongjiu, LI Peiying, ZHOU Lei, JIANG Liming
2020, 37(4): 612-624. doi: 10.11829/j.issn.1001-0629.2019-0400
[Abstract](2935) [FullText HTML] (1033) [PDF 944KB](30)
To ensure reseeding survival rate, we measured the effects of different dilution multiples (× 10, × 100, × 1 000, × 3 000, × 5 000, × 10 000) of a variety of microbial inoculants on seed germination percentage, germination energy, root length, bud length, and seedling weight per plant of Seriphidium transiliense. Suitable seed treatment methods were then selected using principal component analysis and membership functions. The results showed that seed germination percentage, germination energy, root length, bud length, and seedling weight per S. transiliense plant increased with suitable dilution multiples of microbial inoculants; further, compared with the control, these indexes were significantly higher or did not differ significantly. The only exception was compound Bacillus, which decreased the seed germination and germination energy. According to a comprehensive evaluation of the membership functions, the microbial inoculants promoted seed germination and seedling growth in the following descending order: B. licheniformis, Paenibacillus polymyxa bacillus, compound B., Amyloliquefaciens, agricultural compound microorganism bacteria, Actinomyces, and EM bacteria. Combined with the potted results of microbial inoculant, B. licheniformis × 1 000, B. licheniformis × 10, B. licheniformis × 5 000, and Paenibacillus polymyxa × 1 000 were better at improving the germination and growth of S. transiliense as a whole and should the first choices for seed treatment before reseeding.
The influence of Loess Tableland slope vegetation type on soil pore characteristics
FENG Lu, DING Kang, QU Yuanyuan, Farhat Ullah KHAN, DU Feng, XU Xuexuan
2020, 37(4): 625-634. doi: 10.11829/j.issn.1001-0629.2019-0514
[Abstract](2305) [FullText HTML] (796) [PDF 808KB](28)
Vegetation was planted on the Loess Tableland slope with the aim of solidifying the slope. The soil pore structure under the influence of vegetation can help increase rainfall infiltration and reduce water erosion hazards caused by slope runoff. In this project, four types of vegetation located on the Changwu Loess tableland slope were chosen as research objects. Undisturbed soil columns were collected from the 0 – 30 cm soil layer. Quantitative analysis of soil porosity, pore number, pore rounding rate, and pore fractal dimension was carried out using computerized tomography scanning and image-processing techniques. The main factors affecting the structure of the soil pores were analyzed in combination with the physicochemical properties of the soil layer samples. The results showed that pore size did not differ significantly between cropland and Platycladus orientalis vegetation types. Grassland and Hippophae rhamnoides roots increased porosity and pore number and reduced pore-rounding rates. Grassland and Hippophae rhamnoides vegetation types are therefore favorable for rainfall infiltration, making these the preferred choices for creating solid slopes. There was a significant (P < 0.001) or (P < 0.05) correlation among soil organic matter and clay content and pore parameters, and changes in these parameters had an important effect on soil pore characteristics.
Effects of enclosure on the soil seed banks of sand-fixed Pinus sylvestris var. mongolica forests
FANG Xiang, WANG Dongli, LI Jia, LYU Gang, WANG Kai, LIAN Zhao, LIU Yang, QIAN Xiaotong
2020, 37(4): 635-644. doi: 10.11829/j.issn.1001-0629.2019-0299
[Abstract](3315) [FullText HTML] (755) [PDF 755KB](17)
The effects of enclosure on the properties of sand-fixed Pinus sylvestris var. mongolica forests were examined. A total of four forests were chosen as study sites: one that had been semi-enclosed for 5 years (E5), one that had been fully enclosed for 10 years (E10), and two unenclosed control forests (CK1, and CK2). Species composition, density, vertical distribution characteristics, and species diversity of the soil seed bank of the different P. sylvestris forest sites were analyzed by combining field investigations, sampling, and indoor germination tests. The results showed that there were 20 species belonging to 9 families and 18 genera in forests that were semi-enclosed for 5 years, 15 species belonging to 7 families and 13 genera in CK1, 17 species belonging to 6 families and 15 genera in forests that were enclosed for 10 years, and 15 species belonging to 6 families and 13 genera in CK2. In enclosed forests, the annual plants, perennial plants and shrubs and semi-shrubs accounted for 47.83%, 39.13% and 13.04% of all species, respectively. While the annual plants, perennial plants and shrubs and semi-shrubs accounted for 50%, 38.89% and 11.11% of all species in the control forests, respectively. The soil seed bank densities of the understory vegetation in CK1, E5, CK2, and E10 plots were 6 741.5, 8 529.7, 11 559.7, and 7 836.9 grains·m–2, respectively. The density of the soil seed bank was greatest in the 0 – 2 cm soil layer, suggesting surface aggregation. The vertical distribution of the soil seed bank density in enclosed forest sites was consistent with that of unenclosed forest sites. The Margalef richness index of the enclosed forest site was higher than that of the control forest site. The Shannon-Wiener index, Simpson dominance index, and Pielou evenness index of the E5 forest site were lower than those of the control forest sites, but the opposite was true for E10 sites. The similarity index for the species composition of the soil seed bank between enclosed and control site was 0.88. Leguminous plants were very different between enclosed and control sites. In conclusion, 5 years of semi-enclosure can increase the species richness of communities and increase the proportion of perennial plants and shrubs as well as increase the density of the soil seed bank. At the same time, enclosure can increase the community development potential and improve ecosystem stability, so as to ensure the stability and development of sand-fixing P. sylvestris forests.
Study on the geochemical cycles of carbon and nitrogen in shrub encroachment soils
LIU Chaowen, MA Wenming, ZHOU Qingping, CHEN Hong
2020, 37(4): 645-657. doi: 10.11829/j.issn.1001-0629.2019-0481
[Abstract](2010) [FullText HTML] (926) [PDF 665KB](34)
Shrub encroachment is one of most pressing ecological concerns within terrestrial ecosystems as it is an important process of grass soil carbon stocks. Shrub encroachment is the result of the combination of global climate change, rainfall, fire, and biological activities and has a significant impact on regional environments, climate, soil properties, and the carbon cycle. At present, the impacts of shrub encroachment on ecosystems are still unclear, and differences in soil organic carbon and nitrogen reserves, nutrient cycling, and soil greenhouse gas emissions have all been reported after shrub encroachment under different climates and rainfall gradients. This paper summarizes and reviews the effects of shrub encroachment on aggregate stability, enzyme activity, and soil carbon and nitrogen cycling. Shrub encroachment alters the stability and enzyme activities of soil aggregates, which affects soil respiration and the storage, decomposition, and recycling of soil-derived materials. This will significantly affect regional and global climate change. Therefore, this paper proposes strengthening the long-term localization of experimental observations of the shrub formation process to understand the controllable influencing factors underlying shrub encroachment. In addition, this paper recommends strengthening the stability of the soil organic carbon pool and soil aggregates within the carbon and nitrogen cycle after shrub encroachment.
Effects of jasmonic acid pretreatment on perennial ryegrass seed germination under heat stress
SU Yanning, WANG Ruijia, CAI Jiabang, TANG Mingyu, LIAO Zongchao, YANG Xinying, ZHANG Xinquan, NIE Gang
2020, 37(4): 658-668. doi: 10.11829/j.issn.1001-0629.2019-0443
[Abstract](3299) [FullText HTML] (965) [PDF 504KB](20)
Using perennial ryegrass varieties ‘Mathilde’ and ‘Esquire’ as test materials, we evaluated the effects of different temperatures (20, 25, 30, and 33 ℃) and jasmonic acid concentrations (5, 10, 20, 40, 60, 80, and 100 μmol·L–1) on the seed germination of perennial ryegrass. To a certain degree, the results demonstrated that high temperature stress affected the germination characteristics of perennial ryegrass seeds. The germination rate, germination potential, and germination index of perennial ryegrass seeds decreased significantly with increasing temperature, especially affecting root and seedling length. Notably, the germination characteristics of ‘Mathilde’ were better than ‘Esquire.’ Under high temperature stress, the germination ability of perennial ryegrass seeds was significantly improved by soaking seeds in jasmonic acid concentrations between 40 and 60 μmol·L–1. Meanwhile, the superoxide dismutase (SOD) activity of the seedling significantly increased while the malonic dialdehyde (MDA) content decreased. Treatment with an appropriate concentration of jasmonic acid could efficiently improve the germination ability and activity of perennial ryegrass seeds under heat stress.
Physiological correspondence of four varieties of perennial ryegrass to drought stress
ZHAO Chuncheng, LI Xiaoning, ZHANG Yinkun, ZHANG Ting, FU Jinmin
2020, 37(4): 669-677. doi: 10.11829/j.issn.1001-0629.2019-0528
[Abstract](2073) [FullText HTML] (1006) [PDF 967KB](24)
In order to study the drought resistance of different varieties of perennial ryegrass (Lolium perenne), four perennial ryegrass varieties were selected, and turf quality was determined by hydroponic experiment in the greenhouse using Macrogol 6000 (PEG-6000) to simulate drought stress. The physiological indexes of perennial ryegrass were determined, such as turf quality, aerial growth and root growth, water content, chlorophyll content and antioxidant enzyme activity. Results showed that after ten days of drought stress, the growth of the four perennial ryegrass varieties was obviously inhibited, and the water content of the four varieties was decreasing. In addition, the activity of antioxidant enzymes such as superoxide dismutase, peroxidase and catalase in the four varieties initially increased, and then decreased, and the content of malondialdehyde increased. Ranking of drought resistance was carried out using membership function analysis. The results indicated that the drought resistance of the four perennial ryegrass varieties ranked as: Pr521 > Vidas > Larking > Pr525.
Effect of temperature on the components and content of aromatic substances in ‘Purple Ruffles’ Ocimum basilicum leaves
LI Jiaojiao, SONG Li, ZHOU Xinsheng, YANG Xiuyun
2020, 37(4): 678-684. doi: 10.11829/j.issn.1001-0629.2019-0533
[Abstract](1813) [FullText HTML] (793) [PDF 639KB](16)
Potted ‘Purple Ruffles’ Ocimum basilicum plants were treated with different temperatures; the components and relative content of the leaf aromatic substances were then analyzed using SPME and GC-MS. A total of 55 compounds were detected in the leaves of ‘Purple Ruffles’ O. basilicum at different temperatures; linalool was the main aromatic component of the leaves. The components and relative content of aromatic substances differed among the different temperature treatments. We concluded that 15℃ (day/night, 20℃/10℃) is the ideal growth temperature for extracting aromatic components from the leaves of ‘Purple Ruffles’ O. basilicum.
A bibliometric analysis of the application of grassland ecological restoration technology
JIANG Shengjing, FENG Tianjiao, LIU Guohua, HE Jinsheng
2020, 37(4): 685-702. doi: 10.11829/j.issn.1001-0629.2019-0318
[Abstract](2896) [FullText HTML] (1119) [PDF 1300KB](99)
The degradation of grassland ecosystems seriously affects global ecological security, and it is therefore imperative to explore convenient and effective ecological restoration techniques. By utilizing the literature in the Web of Science core database and CNKI(China National Knowledge Infrastructure) from 2000 to 2018, this paper compared the research status and development trends of grassland restoration technology in China and abroad, and analyzed the implementation effects of different ecological restoration techniques in China. The results showed that research on grassland ecological restoration in China has an increasing trend, with the number of published papers ranking second in the world. At present, there are 20 different kinds of grassland ecological restoration techniques used in China, the main ones including resowing, ploughing, and reasonable grazing. In China, more articles have been published on using fencing than in other countries, but fewer on using fire, mowing, and weed control. In addition, there is a lack of studies on techniques using hay spreading and turf transfer, while the straw checkerboard barriers and grassland deratization are unique to China. In terms of implementation effect, all the ecological restoration technologies showed positive recovery effects on degraded grassland, but the results vary between different ecological restoration targets. This paper puts forward reasonable suggestions for further research on the restoration of degraded grassland in China, aiming to provide scientific direction for future grassland restoration in China.
Literature analysis on the research status and development of grassland conservation technology
GUAN Zhenhuan, LIU Guohua, HE Jinsheng
2020, 37(4): 703-717. doi: 10.11829/j.issn.1001-0629.20190406
[Abstract](1822) [FullText HTML] (805) [PDF 1297KB](60)
Grassland is an important natural resource. With economic development and climate change, it is facing increasingly serious threats. Current grassland protection measures in China have improved local grassland degradation, but have not stopped the overall trend in degradation. Therefore, grassland protection technology needs to be improved to ensure a sustainable future. Based on the practical problems of grasslands in China, this paper starts from both the broad and narrow sense of grassland protection. CiteSpace was used to analyze relevant literature on grassland protection technology from the Web of Science core data set from 2000 to 2019, to compare the status quo and the development trend of similar technologies in the world and China, to produce suggestions for the development of grassland protection technology in China. The results show that although the research influence of grassland protection in China ranks third in the world, the frequency of citation is low, and the advanced grassland protection technology from abroad needs to be used for reference in the Chinese context. Compared with the development of foreign technologies, China needs to improve the construction standards of national parks, promote the cultivation of grasslands, increase the research and development of intelligent mowing, strengthen the selection of biological feed bacteria, and improve traditional fence lines. It is also necessary to reduce the technical cost and enlarge the scope of application of pest control. Research and resources need to be directed toward grassland conservation in order to cope with the problems of grassland ecological function, declining grassland productivity caused by grassland exploitation, natural disasters and pests, in order to leave a legacy of grassland care.
Development and verification of EST-SSR markers in Medicago archiducis-nicolai by transcriptome sequencing
WANG Yingfang, ZHANG Yemeng, LIU Demei, SHEN Yingfang, WANG Haiqing
2020, 37(4): 718-727. doi: 10.11829/j.issn.1001-0629.2019-0435
[Abstract](2976) [FullText HTML] (829) [PDF 665KB](27)
Medicago archiducis-nicolai, which is endemic to the Qinghai-Tibet Plateau and its adjacent regions, is a species of Platycarpae in the genus Medicago. This species is characterized by its superior adaptability to extremely harsh environments. In this study, we developed EST-SSR markers of M. archiducis-nicolai using transcriptome sequencing. Polymerase chain reactions verified 350 of 477 randomly chosen EST-SSR primer sets in M. archiducis-nicolai. Of the verified primer sets, 346 were successfully amplified in M. ruthenica, indicating high transferability of the EST-SSR primers to M. ruthenica. The genetic diversity and structure of M. archiducis-nicolai and M. ruthenica populations were characterized using 64 non-genetically linked EST-SSR loci that did not deviate from Hardy-Weinberg equilibrium. Results show significant inter- and intra-species genetic differentiation of the two species, implying geographic distance and environmental selection influenced intra-species genetic differentiation. The EST-SSR markers developed in this study provide useful tools for detailed characterization of the genetic diversity of M. archiducis-nicolai and M. ruthenica and reveal the mechanisms underlying their adaptation to harsh environments.
Evaluation of traits related to the biological nitrogen fixation in Melilotus albus half-sib families
WU Xingwang, Saman BOWATTE, ZHANG Jiyu, HOU Fujiang
2020, 37(4): 728-735. doi: 10.11829/j.issn.1001-0629.2019-0296
[Abstract](1840) [FullText HTML] (762) [PDF 609KB](21)
In this study, half-sib families of Melilotus albus populations were established in two different locations (Yuzhong and Linze) and their phenotypic variations in relation to biological nitrogen fixation (BNF) were evaluated. Root dry weight (RW), number of nodules per plant (NN), nodule weight (NW), leaf total nitrogen (LTN), leaf total phosphorus (LTP) and the percentage of nitrogen derived from the atmosphere (%Ndfa) in plant leaves were measured. The results showed that the coefficients of variation for these indices were greater than 15%, and principal component analysis identified four groups of half-sib families. The RW, NN, NW, LTN, LTP, and %Ndfa values of group 1 were 4%, 26%, 10%, 17%, 21%, and 11% higher, respectively, than in the control (RX-02). The maximum and minimum values of %Ndfa for half-sib families were 58% and 43%, respectively.The progeny families with good biological nitrogen fixation traits selected in this study can lay a foundation for further breeding of new varieties with strong biological nitrogen fixation ability.
Karyotype analysis of seven species of Salvia
FENG Qi, ZHANG Jiapei, ZHAO Yixuan, SUN Haonan, LIU Dongyun
2020, 37(4): 736-742. doi: 10.11829/j.issn.1001-0629.2019-0420
[Abstract](2898) [FullText HTML] (981) [PDF 688KB](16)
In order to study the characteristics and degree of similarity of Salvia spp., karyotype analysis was performed on root tip cells of S. horminum ‘Oxford Blue’, S. patens ‘Patio’, S. japonica, S. sclarea var. turkentanica, S. farinacea ‘Rhea Blue’, S. farinacea ‘Victoria White’ and S. farinacea ‘Fairy Queen’. The karyotype formula of the seven sample plants was K (2n) = 14 = 6m + 1sm, K(2n) = 18 = 6m + 3sm, K(2n) = 14 = 3m + 4sm, K(2n) = 20 = 8m + 2sm, K(2n) = 16 = 5m + 1sm + 2st, K(2n) = 18 = 2m + 4sm + 3st, K(2n) = 18 = 4m + 5sm, respectively. The asymmetric coefficients (AS.K%) were 56.04%, 61.20%, 61.52%, 60.90%, 62.55%, 73.11% and 66.84%, respectively, and the karyotype classification criteria were “1A”, “2B”, “2A”, “2B”, “2B”, “3B” and “2B”, respectively. According to data inference, the asymmetric coefficient was 73.11%, and the karyotype classification of “3B” type S. farinacea ‘Victoria White’ had the highest degree of evolution, with S. horminum ‘Oxford Blue’ having the lowest degree of evolution. The karyotype classification is closely related to the four samples belonging to “2B” type.
Study on seed morphological characteristics and viability determination method in Apocynum spp. and Poacynum spp.
ZHAO Yufeng, GAO Jihong, ZENG Yanjun, ZHANG Jiyu, WANG Yanrong, WANG Li
2020, 37(4): 743-752. doi: 10.11829/j.issn.1001-0629.2019-0261
[Abstract](1946) [FullText HTML] (765) [PDF 675KB](23)
Seed morphological characteristics, 1 000-seed weight, and viability measurement methods were studied using eight genotypes of Apocynum and Poacynum in Allahak Town, Altay City, Xinjiang Uygur Autonomous Region. Results showed that the mean seed length of Apocynum venetum was 2.75 mm, with a width of 0.68 mm and thickness of 0.49 mm. Among the seven Poacynum genotypes, seeds of the genotype with purple spotted medium flowers were longest, with a mean length of 4.51 mm. Seeds of the genotype with green stems and white flowers were widest, with a mean width of 0.90 mm, and seeds of the genotype with green stems and white flowers and P. hendersonii were the thickest (0.61 mm). The length, width, and height of the eight genotype seeds ranged from 2.75 to 4.51 mm, 0.68 to 0.90 mm, and 0.48 to 0.61 mm, respectively. The purple spotted medium flower was the largest genotype and A. venetum was the smallest genotype. 1 000-seed weight ranged from 0.38 to 1.32 g. All genotypes had brown seeds, but P. hendersonii had the deepest color. Seeds of eight genotypes were characterized by non-dormancy seed germination with a short germination time, which could be used to determine the viability quickly. When viability was measured by tetrazolium staining, all tested seeds showed impermeable tetrazolium. The seed coat was cut vertically after a pre-wetting period of 12~14 hours, then cut seeds were dyed for 12 hours. The identification criteria was 80% staining of seed embryos. This experiment mainly carried out the research on the morphological characteristics and viability measurement methods of Apocynum and Poacynum, which can provide a certain basis for the identification of venetum seed viability, large-scale planting, and seed breeding
Screening of the best mixed ratio of Avena sativa and × Triticale Wittmack in the high-cold area of Guoluo, Qinghai Province
MA Xiaodong, SUN Jinjin, WANG Pengbin, ZHAO Yishan, SONG Meijuan, YU Xiaojun
2020, 37(4): 753-761. doi: 10.11829/j.issn.1001-0629.2019-0466
[Abstract](3591) [FullText HTML] (779) [PDF 660KB](18)
In order to determine the optimal ratio of Avena sativa and × Triticale Wittmack in the “Source of Three Rivers” region, a mixed treatment of A. sativa and × Triticale Wittmack was carried out in Gande County, Qinghai Province. The results showed that the mixed hay yield of the combination of A. sativa 60% + × Triticale Wittmack 40% was the highest of the five mixed treatments, at 13 605 kg·ha–1, and the treatment was significantly higher than that of monoculture yields (P < 0.05). There was no significant difference between A. sativa 50% + × Triticale Wittmack 50% (P > 0.05). The plant height of A. sativa was greatest in the A. sativa 60% + × Triticale Wittmack 40% treatment. This was 6.5% higher than the value under A. sativa alone. The yield per plant and the underground biomass per plant of A. sativa treated with A. sativa 60% + × Triticale Wittmack 40% was significantly higher than that of A. sativa alone, and other mixed treatments (P < 0.05). The yield per plant of × Triticale Wittmack was highest in A. sativa 60% + × Triticale Wittmack 40%. The content of acid and neutral detergent fiber (ADF and NDF) of A. sativa and Triticale treated with A. sativa 60% + × Triticale Wittmack 40% was lower than that of the monocultures, and A. sativa 60% + × Triticale Wittmack 40% had the highest crude protein content. The comprehensive evaluation of the optimal ratios was carried out by using the relative values of hay yield, crude protein content, soluble sugar content, starch content, ADF and NDF content, and was determined as A. sativa 60% + × Triticale Wittmack 40%.
Effects of polymer-coated nitrogen fertilizer combined with different potassium fertilizer dosages on physiological indicators and yield of ryegrass
CHEN Junjie, ZHU Sanming, HAO Miao, HAN Tongyu, LI Yu, WANG Gaoyang, YANG Xiuyi, GENG Jibiao, CHEN Jianqiu
2020, 37(4): 762-769. doi: 10.11829/j.issn.1001-0629.2019-0503
[Abstract](3021) [FullText HTML] (742) [PDF 505KB](22)
To determine the best fertilization ratio for the growth of ryegrass (Lolium perenne), a potted experiment was performed to study the effect of polymer-coated nitrogen fertilizer combined with different potassium fertilizer dosages on the growth characteristics and yield of ryegrass. Compared with common urea, the polymer-coated nitrogen fertilizer significantly increased the SPAD (soil plant analysis development) value, plant height, leaf area, net photosynthetic rate, prolonged the green stage, and prevented the premature senescence of ryegrass (P < 0.05). Using the same amount of potassium fertilizer, the SPAD values of four grass cuttings increased by 11.2%, 6.9%, 33.6%, and 195.2%, respectively, and the plant height increased by 14.1%, 6%, 25.1% and 85.4%, respectively. Compared with urea treatment, polymer-coated nitrogen fertilizer increased the dry mass weight of ryegrass by 12.4%~25.0%. The leaf area index and net photosynthetic rate of ryegrass increased maximally following polymer-coated nitrogen fertilizer with moderate amounts of potassium fertilizer. Thus, it is recommended as an optimal fertilization ratio, providing a theoretical basis for the rational application of nitrogen and potassium fertilizer in ryegrass production.
Comparison of productivity and feed value of different forage plants in the semi-arid regions of the Loess Plateau, China
HUANG Ze, CUI Zeng, LIU Yifan, LIU Yu, WU Gaolin
2020, 37(4): 770-776. doi: 10.11829/j.issn.1001-0629.2019-0438
[Abstract](1897) [FullText HTML] (706) [PDF 475KB](17)
In order to select suitable forage plants for semi-arid regions, three typical forage crops, including forage corn (Zea mays), forage sorghum (Sorghum bicolor) and sudangrass (Sorghum sudanense), and two forage grasses alfalfa (Medicago sativa) and siberian wildrye (Elymus sibiricus), were selected to compare and analyze their dry matter yield, nutritional quality and forage value. The results showed that the plant height of sorghum (from Japan) was the highest (289.25 cm), which was approximately 10% higher than that of sweet sorghum and maize. The plant height of sudangrass SP20 (from America) was the lowest (172.80 cm). The dry matter yield of sweet sorghum was the highest (17.38 kg·m–2), followed by sorghum (12.35 kg·m–2), both of which were higher than that of maize (P < 0.05). The content of neutral detergent fiber (NDF) and acid detergent fiber (ADF) in sudangrass was relatively low, and the difference between sweet sorghum and forage maize was not significant (P > 0.05). The relative feed values (RFV) of sudangrass and alfalfa were highest (135~143), followed by forage maize and sweet sorghum (107~109), and sorghum and siberian wildrye were the lowest (95~102). It was concluded that sweet sorghum had similar forage value to forage maize, but had a higher yield, which has greater development potential in semi-arid areas.
Effect of the mixture of sorghum-sudangrass hybrids and Vicia sativa on digestibility and gases metabolism in lambs
GUO Pei, ZHANG Cheng, WANG Chunmei, YU Zhuo, HOU Fujiang, NAN Zhibiao
2020, 37(4): 777-783. doi: 10.11829/j.issn.1001-0629.2019-0196
[Abstract](1930) [FullText HTML] (786) [PDF 616KB](30)
The present study was conducted to evaluate the effects of sorghum-sudangrass basal diet with common vetch (Vicia sativa) supplementation on the apparent digestibility and greenhouse gas emission in sheep. Twelve crossbred male lambs (6 months old) were randomly assigned to two diets: Diet-1, only sorghum-sudangrass and Diet-2, sorghum-sudangrass with standard vetch supplementation (sorghum-sudangrass ꞉ common vetch = 2 ꞉ 1). There were 15 days for diet adaptation and 9 days for data collection. The dry matter (DM) intake, digestibility of neutral detergent fiber (NDF), and crude protein (CP) of sheep in Diet-2 were significantly higher than those in Diet-1 (P < 0.05). However, there were no differences in the digestibility of DM and acid detergent fiber (ADF) (P > 0.05). The results suggested that sorghum-sudangrass basal diet with standard vetch supplementation could improve the palatability of sudangrass basal diet and increase the apparent digestibility. Common vetch supplementation has the potential to improve growth performance, but further study is needed. This study provides new information for the application and utilization of common vetch.
Determination of peptide nitrogen in ruminant digesta
LI Miaoshan, WANG Hucheng, ZHANG Xia
2020, 37(4): 784-790. doi: 10.11829/j.issn.1001-0629.2019-0284
[Abstract](23015) [FullText HTML] (1589) [PDF 617KB](45)
In the present experiment, the cattle digesta from the rumen and abomasum were used to establish a moderate method for the determination of the peptide nitrogen content of the ruminant gastrointestinal digesta using the L9 (34) orthogonal design. The effects of the Tris-HCl buffer concentration (0.02, 0.04, or 0.06 mol·L–1), Tris-HCl buffer pH (6.8, 7.4, or 8.0), ratio of dry digesta to Tris-HCl buffer (1∶15, 1∶20, or 1∶25), and extraction time (40, 60, or 80 min) on the determination of the peptide nitrogen content in the cattle gastric digesta were studied. The results show that the moderate separation conditions of nitrogen from cattle gastric digesta were 0.06 mol·L–1, 6.8, 1∶25, and 60 min, respectively, and the maximum contents of peptide nitrogen were 14.97 mg·g–1 and 19.28 mg·g–1 in the rumen and abomasum digesta, respectively.
Comparison of the production performance and economic benefits of three different forage planting models in the alpine grazing area of Gannan
PEI Yabin, DU Wenhua, LIU Hancheng, LIU Cui, TIAN Xinhui
2020, 37(4): 791-799. doi: 10.11829/j.issn.1001-0629.2019-0298
[Abstract](24350) [FullText HTML] (1929) [PDF 642KB](87)
To understand the production performance and economic benefits of three different forage planting models in the alpine grazing area of the Qinghai-Tibet plateau, five planting models (autumn seeding triticale intercropped with vetch, 50% spring seeding triticale mixed with 50% vetch, autumn seeding triticale, spring seeding vetch, and oats) were used. Parameters, including the fresh weight, hay yield, nutritive value (crude protein content, acid detergent fiber content, and neutral detergent fiber content), economic benefits, and soil nutrient contents, were determined. The results showed that the treatments of autumn seeding triticale intercropped with vetch and 50% spring triticale mixed with 50% vetch, obtained hay yields of 14.06 and 12.31 t·ha–1, respectively, which was significantly higher than those of the other planting models (P < 0.05). Their net incomes were 6 286 and 11 011 CNY·ha–1, respectively. In addition, these two planting models can significantly improve the soil total nitrogen content, and can be used as efficient planting models in the Gannan alpine pastoral area.
Dependency between herdsmen’s diversified livelihoods and grassland ecosystem services: Taking the Kalajun World Natural Heritage Site as an example
HU Jiran, YAO Juan
2020, 37(4): 800-811. doi: 10.11829/j.issn.1001-0629.2019-0425
[Abstract](3999) [FullText HTML] (813) [PDF 546KB](23)
Herdsmen rely on ecosystem services and have an impact on the ability of these ecosystems to provide services. This research reveals the characteristic rules of the dependency that exists between the livelihoods of herdsmen in pastoral areas and ecosystem services and provides important information that can be used to achieve the coordinated development of both human well-being and ecosystems. The Index System of Farmer Dependence on Ecosystem Services (IDES) exponential model was used to analyze the data from 190 sample herdsmen and delve into the dependencies of four livelihood strategies on ecosystem services, including outward employment, tourism, animal husbandry, and the combined industry of animal husbandry and tourism. Furthermore, using a grey correlation model, we also discuss the impacts of the livelihood capitals of these four kinds strategies on IDES. The results showed that: 1) There was a significant difference among herdsmen in their incomes from ecosystem services. Herdsmen that worked in tourism received the most benefits and received the most from cultural services, with 15 564 CNY on average per household. However, they benefited the least from the modulation sector with an average of 428 CNY per household. 2) The dependencies of different livelihood strategies on ecosystem services differed, here listed in descending order: the combined industry of animal husbandry and tourism, tourism, outward employment, and finally animal husbandry. 3) The correlations between the livelihood capitals of different livelihood strategies and IDES also varied, with the strongest correlation between social capital and IDES, while the correlations between other capitals and IDES were moderate. Based on these findings, it is important to encourage herdsmen to moderately develop by-businesses, and to improve the supply ability of ecosystem services: the participation mechanisms of grassland tourism should be improved to increase the dependence on cultural services. In addition, we should increase the social capitals of herdsmen and strengthen the correlations between livelihoods and ecosystem services. Only in these ways can we achieve the sustainable development of both livelihoods and ecosystem services.
Optimized research on compound straw pellet feed production process
ZHANG Hailong, ZHAO Fangfang, ZUO Zhi, MA Yajie, SHI Bin'gang, WANG Peng, ZHANG Wei, LI Shaobin, ZHAO Zhidong, HU Jiang
2020, 37(4): 812-818. doi: 10.11829/j.issn.1001-0629.2019-0304
[Abstract](1557) [FullText HTML] (736) [PDF 453KB](18)
To improve the production efficiency, product quality, and commercialization level of forage pellet feed, this trial used corn stalk and alfalfa hay as raw materials (by quality ratio 1∶1) to evaluate the optimized production process of compound straw pellet feed. Firstly, the effect of moisture on the molding rate of mixed straw powder was examined using the single factor test design. The moisture was detected as 8%, 10%, 13%, 16%, 19%, 22%, and 25%. The results indicated that the molding rate of compound straw pellet feed showed a downward trend with increased moisture content. The molding rate of pellets was significantly higher than that of other treatment groups, especially for the no moisture addition treatment (P < 0.05). Secondly, the optimal production process parameters for the compound straw pellet feed were evaluated by using the L9 (34) design orthogonal test, moisture (8%, 10%, and 13%), raw material pulverization particle size (4, 6, and 8 mm), and mold hole diameter (6, 7, and 9 mm); the molding rate, hardness, and density were used as indexes of influencing factors. The order in which the influencing factors affected the quality of compound straw pellet feed was mold hole diameter, raw material pulverization particle size, and moisture addition. The optimal production process parameters were 7 mm mold hole diameter, 8 mm pulverization particle size, and 8% moisture.
Introduction to turf extension work in universities of the United States and its reference value to the development of turfgrass science in China
XU Lixin, WANG Sheng, CHENG Liang, HAN Liebao
2020, 37(4): 819-826. doi: 10.11829/j.issn.1001-0629.2019-0441
[Abstract](1578) [FullText HTML] (686) [PDF 435KB](26)
In the United States, most faculty members who specialize in turfgrass science are required to fulfill a certain amount of extension work. Usually, the required percentage of such work is assigned at the appointment of employment. Meanwhile, students are encouraged to participate in outreach activities. This is quite different compared to the Chinese higher educational system where turfgrass science is a developing and relatively new discipline. Most US turfgrass science courses comprise a combination of practical skills and knowledge components, as both problems and solutions can be identified and tested in real-world scenarios. Therefore, extension is extremely important for the development of both the industry and science of turfgrass. In this article, turf extension work in the United States is explored with the intent of informing turf discipline development, particularly turf faculty recruitment and cultivation, for the Chinese higher educational system.