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2017 Vol.34(1)

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2017, 11(1): 0-.
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2017, 11(1): 0-0.
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Orginal Article
2017, 11(1): 1-2.
[Abstract](1008) [FullText HTML] (81) [PDF 1062KB](449)
Evaluation of the regularity of energy formation of sweet sorghum in saline-alkali soils
Yu Cai, Yong-qian Zhang, Ji-li Liu, Na Wu
2017, 11(1): 3-6. doi: 10.11829/j.issn.1001-0629.2016-0177
[Abstract](394) [FullText HTML] (26) [PDF 1564KB](476)
To determine the quality of sweet sorghum energy in saline-alkali soil, and to select the appropriate growth for the area and higher quality energy varieties, a field test was conducted to evaluate the agronomic traits and physiological indexes of sweet sorghum related to the comprehensive evaluation of five different genotypes of sweet sorghum grown in cracking alkali soil. The results showed that under the condition of cracking alkali soil, soluble sugar content and sugar yield of stems of different varieties of sweet sorghum increased with growth, during which the accumulation of large amounts of sugar occurred during the first 20 days after flowering. Soluble sugar content and sugar yield were higher in ZNH18 and ZNH07, followed by ZNH12, and were lowest in ZNH05 and CT-2. Stalk cellulose and hemicellulose content and yield in the genotypes of sweet sorghum decreased with growth. Lignin and yield showed an increasing trend; however, Ligno cellulose content of each component showed some advantages in ZNH18 and ZNH07. In addition, in cracking alkali soil, ZNH18 and ZNH07 could obtain higher grain and biological yield. Therefore, sweet sorghum ZNH18 and ZNH07 could better adapt to cracking alkali soil, with higher sugar, biological, and fibre yield. As such, these are excellent genotypes that are suitable for planting in this environment.
Effects of fencing and grazing management on bud bank in a semiarid steppe on the Loess Plateau
Wei Cui, Ling-ping Zhao, Fu-rong Zhao
2017, 11(1): 9-15. doi: 10.11829/j.issn.1001-0629.2016-0151
[Abstract](1017) [FullText HTML] (97) [PDF 1382KB](408)
In perennial grassland ecosystems, the bud bank plays an important role in vegetation maintenance and recruitment. In this study, we used field root-digging to examine the bud bank, analyze above-ground vegetation characteristics, and below-ground bud bank density, under fencing and grazing management measures. Results showed that the bud bank in a semiarid perennial steppe on the Loess Plateau was dominated by tiller buds, and bud bank density ranged from 832 to 6 848 bud·m-2. Short-term fencing significantly increased the bud bank density and the density of grass bud banks, and decreased the density of forb bud banks in relation to grazed grasslands (P<0.05). The change of tiller buds, rhizomatous buds and root sucker buds caused a change in total bud bank density under two management types. The density of tiller buds and rhizomatous buds was significantly higher and the density of root sucker buds was significantly lower in grasslands fenced for five years than in grazed grasslands (P<0.05). Grass bud bank density was significantly and positively correlated with above-ground biomass, but negatively correlated with above-ground shoot numbers (P<0.05). To a certain extent, the effects of grazing and fencing on aboveground vegetation in a semiarid steppe on the Loess Plateau are mediated through grass bud bank demography. The bud bank is an excellent predictor of the above-ground vegetation. We can predict grassland productivity and succession direction using bud bank determination.
Dynamic assessment of alpine pasture grassland ecosystem health——A case study from the Gannan region
Yu-ting Zhao, Wen-long Li, Di Chen, Cui Yu, Xin-lai Zhao, Jing Xu, Xu-lin Guo
2017, 11(1): 16-29. doi: 10.11829/j.issn.1001-0629.2016-0177
[Abstract](1272) [FullText HTML] (207) [PDF 3888KB](408)
The “Pressure-State-Response” (PSR) model considers the 3 ecosystem aspects of pressure, state, and response. Seventeen indicators were chosen to build a PSR indicator system for the assessment of alpine grassland ecosystem health in Gannan. Using the application of Analytic Hierarchy Process (AHP) and GIS/RS, alpine grassland ecosystem health was assessed from 2001 to 2013. Meanwhile, the spatial and temporal variation characteristics of ecosystem health assessment were analyzed. We found that grassland ecosystem health level can be graded as one of the following levels of health: very low, low, medium, high, and very high, which respectively amount to 3.82%, 23.5%, 0.82%, 53.06%, and 18.81% of the total area. Grassland ecosystems of Zhuoni, Zhouqu, Diebu, Maqu, and Luqu were found to be very high in their level of health, while those of Hezuo, Lintan, and Xiahe were of low health. We also found that the Gannan alpine grassland ecosystem health showed an obviously declining trend over the past 13 years, with 68.01% of the total area deteriorating in health, 27.75% staying the same, and only 4.18% improving.
Estimating grassland coverage based on hyperspectral remote sensing in the northern Tianshan Mountains
Jiao Chen, Li Zhang
2017, 11(1): 30-39. doi: 10.11829/j.issn.1001-0629.2016-0403
[Abstract](982) [FullText HTML] (117) [PDF 1566KB](512)
By taking the Gan’gou Township in Urumqi County on the northern slope of the Tianshan Mountains as the study area, and using an America SVC HR-768 portable spectroradiometer, we collected hyperspectral data and corresponding grassland coverage data at 25 sites. Using these data, we analysed the correlation between grassland coverage and the original spectrum and the first-order differential spectrum and the hyperspectral characteristic variables. We also constructed a hyperspectral estimation model of grassland coverage by using regression methods based on the hyperspectral position variables, the hyperspectral area variables, and the hyperspectral vegetation index variables, and evaluated the accuracy of simulation models. The results showed that there was a strong correlation between grassland coverage and vegetation canopy reflectance in the spectral ranges of 354-704 nm, 1 420-1 481 nm, and 1 904-2 512 nm; the estimation models based on first-order differential spectrum and hyperspectral vegetation index variables can invert grassland coverage better. Model testing indicated that the first-derivate model based on 560 nm y=-384.153x+72.096 can be considered to be the best estimation model of grassland coverage, for which the root mean square error was 7.344% and the estimation accuracy was 90.343%.
Grassland fractional vegetation cover analysis using small UVAs and MODIS——A case study in Gannan Prefecture
Qing-jie Song, Xia Cui, Yao-yao Zhang, Bao-ping Meng, Jin-long Gao, Yu-xuan Xiang
2017, 11(1): 40-50. doi: 10.11829/j.issn.1001-0629.2016-0046
[Abstract](1481) [FullText HTML] (126) [PDF 1954KB](604)
Gannan Prefecture was selected as the study area. Photos of different sized subplots of grasslands were taken with a camera (Canon) and small UAVs (unmanned aerial vehicles). Terra/MODIS MOD13Q1 vegetation indices were obtained from May to October 2015. Correlation analyses were conducted between vegetation indices [enhanced vegetation index (EVI), normalized difference vegetation index (NDVI)] and grassland fractional vegetation cover (FVC), and regression models were determined. Based on the accuracy of different regression models, the best estimation model for grassland FVC in Gannan Prefecture was selected, and grassland spatio-temporal characteristics of FVC during the growing season were analysed. The results showed that 1) small UAVs carrying cameras could be used to obtain digital photos containing data on grassland FVC; 2) EVI was more correlated with grassland FVC than NDVI, and the logarithmic model based on EVI was the most suitable model for monitoring grassland FVC in Gannan Prefecture, with model accuracy reaching 88.00%; 3) grassland FVC of flat meadows in 2015 reached the maximum in August, and the remaining grassland types reached the maximum in July; 4) grasslands in Gannan Prefecture were dominated by high and mid-grassland FVC levels, and these grasslands were mainly distributed in Maqu County, Luqu County, and Xiahe County and Hezuo City. Overall, the grassland FVC in the mid-western and south-western areas was better than that in the eastern area. Establishment of the best model for grassland FVC was beneficial not only in elucidating the spatio-temporal distribution and seasonal dynamic variation of grassland FVC, but also to the maintenance of stable development of grassland ecosystems in Gannan Prefecture.
Analysis on the temporal variation of soil CO2 flux and its response to the environmental factors in Haikou urban lawn—A case study of the south campus of Hainan Normal University
Wen-xian Xu, Zhi-qing Zhuo, Cong-ju Zhao, Min-jie Zhu, Qi Han, Xiao-wei Wu
2017, 11(1): 51-58. doi: 10.11829/j.issn.1001-0629.2016-0415
[Abstract](1025) [FullText HTML] (73) [PDF 1591KB](519)
To explore the change characteristics of soil CO2 flux and its response to air temperatures, soil temperatures, soil moistures and other environmental factors, the soil respiration rates of tropical urban lawn ecosystems were measured by using the LI-8100A Soil CO2 Flux System, and meanwhile air temperatures, soil temperatures at 5 cm and soil moisture 0-10 cm in depth were monitored from November of 2013 to October of 2014. The results showed that: 1) Daily variation of soil respiration was single peak curve. The peaks usually occurred at 09:00-16:00, and the time when peak values generally appeared were different in different months and weather conditions. Yearly variation of soil respiration was also a single peak curve. The mean daily soil respiration rate was 0.86 to 4.27 μmol·(m2·s)-1, with the maximum in June, and the minimum in December. 2) There was a significant positive correlation between soil respiration rate and air temperature and soil temperature. However, the relationship between the CO2 flux and soil volumetric water content was more complex, and the correlation was not significant. 3) Rainfalls had complicated effects on soil respiration. A light rain didn’t significantly change soil respiration, but a heavy rainfall could have an obvious extrusion effect on soil CO2 flux. At the early stage of a heavy rainfall process, soil respiration rate increased with the increase of rainfall, however, continuous rainfall could increase the soil moisture, and rainfall became an important factor limiting soil respiration.
Short-term effect of fungicide on seed germination and seedling growth of standing milk vetch(Astragalus adsurgens)
Bin-hua Yu, Wen-jian Wang, Jian-peng Yin, Yan-chao Wang, Si-yu Yu, Lu-lu Qi
2017, 11(1): 59-66. doi: 10.11829/j.issn.1001-0629.2016-0009
[Abstract](1115) [FullText HTML] (78) [PDF 1434KB](447)
Fungal disease is the main factor reducing perennial forage’s biomass of standing milk vetch (Astragalus adsurgens). In this study, the seeds of standing milkvetch were pretreated with three kinds of fungicide: carbendazim, mancozeb and thiophanate-methyl, with the purpose of evaluating the fungicide effects, seed germination and seedling growth after inoculation through resembling the natural environment. The results suggested that three kinds of fungicide treatments significantly(P<0.05) improved the seed germination in petri dishes and pots compared with sterile water controls, and the plant height, root length as well as dry weight revealed a uniform trend. Significant reductions of incidence, mortality and average disease severity index (DSI) were caused by the fungicides. Based on the results, the fungicides have different roles on seed germination and seedling growth under the pathogen conditions, of which mancozeb was the best choice in this study.
Effects of increased N O-3-N application on PSⅡ function in leaves of Morus alba seedlings under Na2CO3 stress
Nan Xu, Hui-hui Zhang, Si-yu Gu, Xin Li, Yu-wei Zhu, Yan Yang, Kun Liu, Xiu-li Zhang
2017, 11(1): 67-74. doi: 10.11829/j.issn.1001-0629.2016-0249
[Abstract](1002) [FullText HTML] (88) [PDF 2250KB](315)
In this study, we analysed the effects of increased nitrate (N O-3-N) (from 7.5 mmolL-1 to 17.5 mmolL-1) on the growth and photosynthetic characteristics of mulberry seedlings, which were subjected to alkaline salt (50 mmolL-1 Na2CO3) stress using hydroponic methods. The results showed that plants displayed obvious symptoms of injury when subjected to 50 mmolL-1 Na2CO3 stress. Furthermore, compared with the control, the photochemical reaction centre activity of PSⅡ in stressed seedlings was significantly decreased, and electron transport was affected to different degrees on both the donor side and receptor side of PS Ⅱ. Under Na2CO3 stress, increasing N O-3-N promoted photosynthetic electron supply and transmission capacity, enhanced the function of the oxygen complex in the electron donor of PS Ⅱ, and increased the acceptor electron capacity of the receptor library. In addition, increasing N O-3-N also improved the stability of leaf thylakoid membrane structure, promoted the distribution of more light energy to the photochemical reaction centre, and decreased the proportion of energy in the form waste heat dissipation. In conclusion, increasing N O-3-N enhanced the function of PS Ⅱ under 50 mmolL-1Na2CO3 stress, which ensured the normal operation of photosynthesis.
Effects of light intensity and clipping treatment on the compensatory growth of Caragana korshinskii seedlings
Yi Sun, Xing-fu Yan, Li-biao Zhou, Ying-quan Miao
2017, 11(1): 75-83. doi: 10.11829/j.issn.1001-0629.2016-0113
[Abstract](950) [FullText HTML] (74) [PDF 1493KB](370)
Under 3 light intensities of 100% natural sunlight (NS), 37% NS and 16% NS respectively, the experiment was conducted to investigate the effects of light and clipping intensity (non-clipping, stubbled 30 cm, stubbled 20 cm, stubbled 10 cm and stubbled 3 cm) on compensatory growth of two-year-old Caragana korshinskii seedlings. The results showed that: 1) High light and clipping treatment facilitated compensatory growth of C. korshinskii seedlings. Both the sprout number and basal stem diameter of sprout of clipped seedlings maximized under high light intensity, while a decreasing trend was observed with the increasing of clipping intensity. 2) Shoot height (SH), basal stem diameter (BSD), taproot length (TRL), and lateral root number (LRN) of clipped seedlings all presented in the order of 100% NS>37% NS>16% NS in all clipping treatments. SH and BSD of clipped seedlings were lower than those of control and declined with the clipping intensity increasing. Slight clipping treatment accelerated taproot growth and increased LRN, while they were inhibited when clipping intensity increased. 3) High light facilitated the accumulation of biomass of clipped seedlngs, but a decline of total seedling biomass was detected with the increasing of clipping intensity, in another words, biomass accumulation of clipped seedlings appeared as under-compensatory growth. With the decline of light intensity, the compensation index of biomass of clipped seedlings increased and only slightly fluctuation among different intensities of clipping under the lower intensity of 16% NS, suggesting that the biomass accumulation of clipped seedlings mainly depended on new carbohydrate from photosynthesis under high light intensity and on nutrient supply from the root system and stubble under relative low light intensity. The results indicate that the ability of compensatory growth of clipped C. korshinskii seedlings declined with the increasing of clipping intensity and appeared as under-compensatory growth, and that high light can facilitate compensatory growth and biomass accumulation of clipped C. korshinskii seedlings. This result would provide reference for seedling cultivation, forage production and management of grassland ecosystem.
Effects of Cd concentrations on growth, photosynthetic indices and bioconcentration of two Pennisetum during different growth stages
Da-lin Liu, Qi-xin Sun, Jiang Shao, Ming-hui Chen, Hua Zhang
2017, 11(1): 84-93. doi: 10.11829/j.issn.1001-0629.2016-0117
[Abstract](1073) [FullText HTML] (74) [PDF 1459KB](368)
The growth, photosynthetic indices of Pennisetum americanum(ML) and P. americanum×P. purpureum(ZL) under different cadmium(0,5,25,50,75,100 mg·kg-1)were investigated by pot experiment and make a comparison between the two cadmium tolerance and the difference on the absorption and transport of cadmium. Results showed that: 1) the plant height decreased after increasing Cd concentration, fresh weight and dry weight decreased while leaf width changed no significant with the Cd concentration increased at the same growth stage; the indicators above increased gradually with the extension of the growth period at the same Cd concentration, however leaf width and fresh weight of ZL showed bigger; 2) At the same growth stage, Chla and Chlb content in ML were more than ZL. When Cd concentration at 5 mg·kg-1, it showed little effects on the net photosynthetic rate, transpiration rate, intercellular carbon dioxide concentration, but with the Cd concentration increased each treatment became significantly decreased compared with the control(P<0.05), which indicated that high concentrations of Cd treatment had significant effect on the photosynthesis of Pennisetum especially ZL. 3) Growth performance of American pennisetum was better than hybrid pennisetum, while the bioconcentration factor was less, indicating that the former had better tolerance to Cd, and the latter was more suitable for the remediation of cadmium contaminated soil. 4) the root system is the main bioconcentration site and Cd in root part transfered little to the overground part, in three growth stages,the content of Cd was the highest in seedling stage, which showed the seedling stage was when the plant was the most susceptible to Cd stress. ZL had a better effect than ML on the remediation of cadmium contaminated soil. If the soil under low Cd concentrations(<1.0 mg·kg-1), pennisetum still can be used as edible forage.
Correlation, path, and cluster analysis of agronomic characteristics of the F1 population from the cross between Agropyron mongolicum and diploid Agropyron cristatum
Qing-qing Duan, Rong-rui Xu, Xu-qing Li, Yong-he Che, Jin-peng Zhang, Xiu-quan Li, Xin-ming Yang, Wei-hua Liu
2017, 11(1): 94-100. doi: 10.11829/j.issn.1001-0629.2016-0155
[Abstract](968) [FullText HTML] (37) [PDF 1422KB](329)
To explore the relationship among nine agronomical characteristics of Agropyron. and provide the theoretical basis for improving the efficiency of wheat breeding, the F1 generation of the cross between Agropyron mongolicum (female parent) and the diploid A. cristatum (male parent) was analysed. The nine agronomic characteristics of 116 F1 plants was analysed using different methods of data analysis. The results showed that all characteristics exhibited significant genetic variation (11.2%~40.13%). The variation in grains per spikelet and grains per spike were the greatest, with a value of 30.56% and 40.13% respectively. Correlation and path analysis showed that florets per spikelet had a significant effect on thousand kernel weight with an r value of 0.168 (P<0.05) and a direct path coefficient of 0.364. This was followed by spike length (r = 0.235, P<0.05) and kernels per spikelet (r=0.126). The 116 plants of the Agropyron F1 population were clustered into three groups. The first and third group had greater plant height and more foliage. As such, these groups could represent varieties with high-quality forage grass for breeding. The first and third group had numerous positive characteristics, including more florets per spikelet, more spike grains, among others, which represent good germplasm resources for forage grass and wheat breeding.
Comprehensive evaluation of drought resistance in six Elymus breviaristatus accessions from the Northwest Plateau of Sichuan Province at seedling stage
Xin Liu, Kai-xin Fu, Zhi-hui Guo, Xin-quan Zhang, Shi-qie Bai, Da-xu Li, Chang-bing Zhang, Cheng-lin Zhang, Ming Sun, Xiao Ma
2017, 11(1): 101-111. doi: 10.11829/j.issn.1001-0629.2016-0233
[Abstract](1288) [FullText HTML] (90) [PDF 1801KB](341)
Drought tolerance of six Elymus breviaristatus accession samples from the Northwest Plateau of Sichuan Province was investigated over 21 days using a water-controlled potting experiment. Relative water content (RWC), relative electric conductivity (REC), content of proline (Pro), content of chlorophyll (Chl), content of malondialdehyde (MDA), activity of superoxide dismutase (SOD), and peroxidase (POD) of leaves were measured in the control (CK, without drought stress), and on the 7th, 14th, and 21st days after drought stress treatment, respectively. Additionally, drought resistance of germplasms was evaluated using subordinate function analysis. Our results showed that drought stress had significant effects on physiological indices (P<0.05), and significant differences in phenotypic values were observed between drought treatments and the control (CK) (P<0.05). There was also a significant difference detected between the different accession samples (P<0.05). With the extension of drought stress time, RWC and Chl followed a declining trend. By contrast, MDA, REC, Pro and the activity of POD followed a significant rising trend. The activity of SOD increased at first and then decreased. Based on the subordinate function analysis of seven physiological characteristics, the rank order for drought resistance among these E. breviaristatus accessions were as follows: 205176>205133>Red 10-5>204290>Red 6-5>205104.
Effects of water stress on nutritional quality of alfalfa in arid and semiarid areas
Jing-hai Wang, Guang-ping Qi, Yan-xia Kang, Yan-lin Ma, Xiao-wei Shi, Xuan-hao Zhu
2017, 11(1): 112-118. doi: 10.11829/j.issn.1001-0629.2016-0240
[Abstract](972) [FullText HTML] (67) [PDF 1432KB](407)
This study examined the effects of water stress on nutritional quality of alfalfa in arid and semiarid areas, which are under strict controls of water consumption. We conducted a field experiment considering alfalfa under full irrigation conditions (4 200 m3·hm-2), 80% full irrigation (3 360 m3·hm-2), and 60% full irrigation (2 520 m3·hm-2), and measured the stem-leaf ratio and nutritional quality index. We found that throughout the growing season, there were significant differences in the distribution of crude protein, ether extract and crude ash among different cuttings. The size of these differences declined from the first cutting to the third cutting. In leaf-stem ratio, neutral detergent fiber content, and acid detergent fiber content, this trend was reversed. Further analysis showed that in comparison with full irrigation, yield from plants irrigated at 80% increased by 5.10%, and in comparison with 60% full irrigation, yield from plants raised under 80% irrigation increased by 10.60%. Under the same comparisons, crude protein content rose 9.60% and 22.74%, ether extract content rose 3.33% and 7.90%, acid detergent fiber content fell 8.57% and 13.30%, content of neutral detergent fiber fell 6.51% and 11.56%, and crude ash content rose 3.20% and 4.54%. We conclude that 80% full irrigation during the growing season is an optimum level for improving water use efficiency and nutritional quality of alfalfa in arid and semiarid areas.
Effects of grassland plant communities on ramet expansion ability and biomass allocation of Potentilla anserina
Xing Fan, Jian Cai, Jin-ping Liu, de Wu, Ren-xu Zong
2017, 11(1): 119-128. doi: 10.11829/j.issn.1001-0629.2016-0161
[Abstract](900) [FullText HTML] (34) [PDF 1395KB](330)
In this study, Potentilla anserina plants were grown in six types of plant communities characterized by different dominant species. Quantitative traits and biomass structure at three levels (genet, mother ramet, and clone) were measured. The objective of this study was to analyse the differences in space expansion and biomass distribution of P. anserina grown in the different plant communities, and to determine its growth strategies in response to the different communities. The results showed: 1) Community composition had a highly significant effect on the roots of the mother ramet (P<0.01). Compared to the control, root length and root number of the mother ramet in all other communities significantly decreased (P<0.05), and the number of roots and root length of the daughter ramet also showed a decline. However, the number of roots of the daughter ramet was not significantly different in any community. 2) Community composition had a significant effect on the length and diameter of clone stolons and spacer length (P<0.05). P. anserina grown in different communities exhibited greater expansion ability of the genet by reducing stem diameter and increasing spacer length. 3) Community composition had a significant effect on both the horizontal and vertical expansion indices of the genet (P<0.05). P. anserina grown in different communities significantly increased expansion area and space, and decreased expansion entropy, thus increasing efficiency by using the guerrilla growth pattern to obtain needed environmental resources. 4) Community composition significantly reduced biomass accumulation in the levels of ramets (P<0.05). Biomass of the genet preferentially allocated to the mother ramet, and biomass of the mother ramet was preferentially allocated to the leaves. Compared to the control, the biomass allocation ratio of clones declined, but the allocation ratio of stolons exhibited an increasing trend. 5) Community composition had a significant impact on biomass structure of the genet (P<0.05). Compared to the control, the ratio of root to stem and leaf to stem of the genet grown in most communities significantly increased. In summary, P. anserina can survive and grow because it has characteristics of morphological plasticity. Expansion ability and biomass allocation of P. anserina genets perhaps change because of the biological characteristics of the community species and competition among daughter ramets of clones. Further research is needed.
Advances in the molecular biology study of seed aging
Hang Cheng, Ling-ling Chen, Fang-shan Xia, Hui-fang Yan, Pei-sheng Mao
2017, 11(1): 129-137. doi: 10.11829/j.issn.1001-0629.2016-0148
[Abstract](1244) [FullText HTML] (134) [PDF 1437KB](455)
It is necessary to develop the agricultural production of seeds which are considered as basic materials. However, seed aging leads to a decline in seed quality and ultimately to the loss of seed vitality, which causes huge economic losses in agricultural production. Thus, it is very important to conduct research on the aging mechanism, in order to identify suitable methods to control seed aging. Currently, most studies on seed aging focus on physiological and biochemical changes. It is possible to accurately determine the aging mechanism by using the techniques of molecular biotechnology, which are rapidly developing. This paper summarizes the achievements of molecular biology studies on seed aging. The genetic integrity of seeds was found to be lower after aging. Genes related to energy metabolism, signal transduction, stimulus-response, and the glycolytic pathway, among others, were differentially expressed after seed aging. Some genes that participate in lipid peroxidation and repair of DNA damage were identified. Developing trends in the study of the seed aging mechanism are also discussed. Localization of proteins and mRNAs, gene function analysis, and characterization of the signal transduction pathways will be important areas of focus in the future.
Situation and countermeasures of milk safety production in China
Jie Zhang, Dong-ji Shi, Zhao-feng Wang, Fu-jiang Hou
2017, 11(1): 138-147. doi: 10.11829/j.issn.1001-0629.2016-0223
[Abstract](2016) [FullText HTML] (238) [PDF 1556KB](544)
Milk production and occupancy per capita over the last 15 years in China can be divided into two periods of time: a rapid growth period (2000-2007, with average annual increases of 22.64% and 21.97%) and a slow growth period (dating from the 2008 “melamine” milk powder incident, with the average annual increase of 0.72% and 0.49%). Since 2000, the milk production and milk occupancy per capita of China have respectively increased 4.35 and 4.11 times, but is still 1/3 of the milk production in the United States and 1/2 of that in India, and milk occupancy per capita is still less than 1/10 of that in the United States and 1/2 of that in India. The per capita dairy consumption of urban and rural residents increases linearly with increase in milk yield and dairy product importance, with respective average annual increases of 5.35% and 15.77%. China’s milk production has a significant impact on rural dairy consumption, and dairy imports have a significant effect on dairy consumption of both urban and rural residents. Through a comparative analysis of domestic and international information, it can be concluded that China’s milk production system should speed up the grass planting-dairy production-milk processing-milk sales of the longitudinal system coupling, and strengthen the production of many units through the contract system of lateral coupling. According to the theory of four production layers of grassland agriculture, our next steps should be to establish dairy production supervision and protection, from the level of soil and water conservation to the level of consumption, to improve the income distribution mechanism of dairy industry chain based on forage grass planting and dairy cattle breeding, and to take advantage of the integrated systems of grassland and dairy cattle.
Effect of castration on meat quality of simmental cattle
Tong-jun Guo, Chang-jiang Zang, Lian-qun Wang, Duan-ji Sang, Xiong Yu
2017, 11(1): 152-160. doi: 10.11829/j.issn.1001-0629.2016-0212
[Abstract](1039) [FullText HTML] (91) [PDF 1369KB](356)
We investigated meat quality of Simmental cattle, aged from 17 to 21 months, after castration. Fifty healthy Simmental bull calves at 16 months of age were classified into two groups. Twenty-five were assigned to either the castrated or the uncastrated group according to their body weight. Both groups were fed the same diets according to their nutrient requirements during the 150 days of experiment. Our results showed that the myoglobin concentration of beef was higher in the castrated group than in the uncastrated group (P<0.01). Additionally, the pH was significantly lower in beef from castrated bulls (P<0.01), and the marble patterns, fat, dry matter, oleic acid, monounsaturated fatty acid (MUFA)/saturated fatty acid (SFA), and MUFA/polyunsaturated fatty acid (PUFA) contents were significantly high (P≤0.05). Stearic acid content tended to decrease in the castrated group than in the uncastrated group (0.05<P≤0.10). The results suggested that castration can promote the marbling grade of meat, improve the color, increase the content of fat and dry matter, and enhance oleic acid and unsaturated fatty acid content. We recommend castration at 1.5 years of age for Simmental cattle for optimum meat quality.
Semiarid area should develop dry farming grasslands
Xiang-yang Hou
2017, 11(1): 161-164. doi: 10.11829/j.issn.1001-0629.2016-0164
[Abstract](829) [FullText HTML] (53) [PDF 1260KB](372)
Grass based livestock production is one of the most important pillar industry in semiarid area of Western China. In this paper, we discussed the strategic meaning of changing grain to forage and developing cultivated grassland. On the basis of this, we analyzed the restrains of this area in water, soil and natural resources. Then, we suggested that dry farming grasslands should be developed in this area and that different parties should act collectively and strengthen the researches and extension on theories and techniques of dry farming grassland.
Influence of variety and growth period on the nutrient content and in vitro gas production characteristics of Stylosanthes
Ya-ge Zhang, Mao Li, Han-lin Zhou, Lin Hu, Wei Li, Tie-shan Xu
2017, 11(1): 165-172. doi: 10.11829/j.issn.1001-0629.2016-0189
[Abstract](881) [FullText HTML] (72) [PDF 1640KB](302)
This experiment was conducted to investigate the influence of variety and growth period on the nutrient content of Stylosanthes guianensis cv. Reyan No. 2, S. guianensis cv. Reyan No. 20, and S. guianensis cv. Reyan No. 21, and the in vitro gas production characteristics. The results showed that S. guianensis cv. Reyan No. 2 had higher content of crude protein(CP)and crude fat(EE) than did S. guianensis cv. Reyan No. 20 and S. guianensis cv. Reyan No. 21 in terms of nutrients, but the in vitro gas production of the three varieties was similar, except for S. guianensis cv. Reyan No. 21, which had lower in vitro dry matter digestibility(IVDMD) and microbial protein content(MCP). Content of some nutrients in Stylosanthes, such as crude protein, acid detergent fiber(ADF), neutral detergent fiber(NDF), and relative feed value(RFV), presented obvious regularity following the growth periods. The content of CP initially increased, subsequently decreased, and reached a maximum in the initial flowering stage. The content of ADF and NDF increased with growth, and RFV gradually decreased. It was concluded that Stylosanthes have a high content of CP and low fibre content, and are high-quality forage for domestic animals. It was also concluded that the vegetative stage was the proper growth period for animal feed.
Effects of the addition of different additives and biological agents on the quality of potato stem and leaf silage in Shigatse
Wan Xie, Xi-zhen Yang, Li Yang, Lei Liu, Danzengwangmu, Wei-lie Zheng
2017, 11(1): 173-185. doi: 10.11829/j.issn.1001-0629.2016-0112
[Abstract](947) [FullText HTML] (90) [PDF 1406KB](285)
Fresh potato stems and leaves were used as raw material to produce silage in a laboratory-scale experiment in Shigatse. Formic acid, urea, salt, and six different types of biological agents (A, active lactic acid bacteria freeze-dried powder;B, YIJAYI straw fermentation agent; C, QIANMU EM bacteria seed; D, BAIYIBAO EM strain; E, WEITEMEI probiotic bacteria; F, degradation agent of coarse fodder) were used as ensiling additives. Corn flour, wheat bran, polymeric grass, alfalfa, forage maize straw, forage corn stalk, oat straw, barley straw, and rape shell were used to prepare mixed silage. Silage was vacuum-packed in polyethylene bags. On the basis of biochemical analysis and sensory evaluation, we adopted the subordinate function method to evaluate silage quality. The results obtained were as follows. Silage completed fermentation and after 30 days entered a stable stage, which can effectively maintain moisture and nutrients for a long time. The quality of silage produced with potato stems and leaves individually was poor, but could be improved by adding biological agents, i.e., formic acid, wheat bran, corn flour, forage maize straw, and oat grass. Among these, wheat bran was better than corn flour, and forage maize straw was better than oat grass. Although polymeric grass and alfalfa are nutritious, their high water contents result in poor fermentation when ensiled with potato stems and leaves. Rape shell is not suitable for mixed storage with potato stems and leaves. Among the biological agents assessed, the fermentation effects of A and B were better than those of E and F. The effects of the following three silage treatments are best: Potato stems and leaves+30% wheat bran, potato stems and leaves+0.3% urea+0.4% salt+30% wheat bran+D, and potato stems and leaves+30% wheat bran+B.
Optimization of anthocyanidin extraction from Anemone obtusiloba using response surface methodology
Wen-lin Lan, Zuo-jun Liu, Zhi-peng Liu
2017, 11(1): 186-193. doi: 10.11829/j.issn.1001-0629.2016-0062
[Abstract](1414) [FullText HTML] (47) [PDF 2089KB](392)
In this study, we used the sepals of Anemone obtusiloba as experimental material for extraction of anthocyanidin using response surface methodology. Four factors were selected in this experiment: the material liquid mass concentration, pH, extraction time, and extraction temperature. We selected the light absorption value of the anthocyanidin of A. obtusiloba as a response surface to optimize the extraction conditions of anthocyanidin. Our results confirmed that the most efficient extraction of anthocyanidin was achieved under the following conditions: a material liquid mass concentration of 70 g·mL-1, an extraction temperature of 61 ℃, an extraction time of 87 min, and pH 3.8. Under these conditions, we conclude that the best light absorption value of A. obtusiloba is 0.154 5.
Theory and practice of Qian Xue-sen’s deserticulture and prataculture
Liang Chen, Han-jin Hu
2017, 11(1): 194-202. doi: 10.11829/j.issn.1001-0629.2016-0159
[Abstract](1147) [FullText HTML] (196) [PDF 1349KB](312)
The practices of deserticulture and prataculture have been developing in China since their suggestion by Qian Xue-sen in 1984. After more than 30 years, deserticulture and prataculture have made remarkable achievements. Aspects of research can be reviewed from several points: those proposed by background and significance, the development of ideas, stage achievements, academic debate, prospects for the development, and other several aspects. It is suggested that the theory of deserticulture and prataculture which proposed by Qian Xue-sen presently has very important practical significance, and with the continuous development of science and technology, the prospect of further development is will be beneficial.
Spatial pattern of population-economic pressure in the northern slope pastoral areas of Qilian Mountain
Fa-lin Wei, Yue-e Yan, Xiao-lei Zhou, Yun-rui Ma, Xun-ling Huo
2017, 11(1): 203-211. doi: 10.11829/j.issn.1001-0629.2015-0531
[Abstract](834) [FullText HTML] (71) [PDF 1355KB](244)
In this study, we investigated the spatial distribution pattern of population-economic pressure in the Qilian Mountain northern slope pastoral area by employing principal component and cluster analyses. The results indicated there were striking regional characteristics in the spatial distribution pattern of population-economic pressure in the research area. The specific performances indicated the following. The western region had advanced economies, high population growth rate, and population economic pressure was small. The population-economic pressure here showed a negative correlation. The eastern region had a poor natural environment. The population-economic pressure here showed a positive correlation, and population economic pressure were large. In the central region, the population-economy pressure indexes showed a negative to positive correlation with the developing economy.