Welcome Pratacultural Science,Today is

2016 Vol.33(3)

Display Mode:          |     

2016, 10(3): 352-352.
[Abstract](536) [FullText HTML] (23) [PDF 301KB](427)
The type and productivity of grassland grazing system
Fu-jiang Hou, Jiao Ning, Qi-sheng Feng
2016, 10(3): 353-367. doi: 10.11829/j.issn.1001-0629.2016-0035
[Abstract](1144) [FullText HTML] (180) [PDF 1962KB](631)
According to the Comprehensive and Sequential Classification System(CSCS), the grazing system is classified into eight categories as alpine steppe, desert, semi-desert, subtropical forest shrub, typical steppe, meadow steppe, temperate forest shrub and tropical forest shrub. The succession stages of grazing systems are original nomadism, extensive nomadism, overgrazing and modern grazing. According to long-term productivity dynamic of three grazing systems, China is still in the overgrazing stage, and converting to modern farming system. Average production capacity of grazing system in China is 18.04 APU·ha-1, and the total production capacity is 6.35 billion APU. The national meat production is 2.959 million t·a-1. The grazing system was structurally overloaded in China, namely the overall overload. Meanwhile, there are still potential increase in seasonal utilization in some region. At present, the potential to increase grassland productivity potential is about 0.5 to 2 times in China, the key measure is the transform into the modern grazing systems in China.
The characteristics of plant species and soil quality in the restoration process of the Loess Hilly Region
Chao-yu Xue, Feng Jiao, Hai-dong Zhang, Hai-li Ru
2016, 10(3): 368-376. doi: 10.11829/j.issn.1001-0629.2015-0428
[Abstract](783) [FullText HTML] (66) [PDF 682KB](480)
Using the methods of comparative analysis and substituting temporal serial with spatial serial, the changing characteristics of plant communities biomass and soil nutrient in the process of plant restoration were studied based on the survey data of abandoned lands in the Loess Hilly Region with the five different ecological restoration periods (0-5,6-10,11-15,16-20,and 21-25 years). The results showed that the main dominant species in the Loess Hilly Region with these five plant restoration periods were Leymus scalinus, Artemisia scoparia, Lespedeza davurica, Stipa bungeana and Bothriochloa ischaemun, respectively. Generally, Simpson index, Shannon-Wiener index, Pielou index and Margalef index increased firstly and then decreased which suggested that the ecological system in the Loess Hilly Region can gradually improved by both natural and artificial restoration modes. With the increase of restoration period, the aboveground biomass, soil organic matter, total nitrogen and available nitrogen content decreased firstly and then increased, however, the total phosphorus content changed in opposite way. The soil nutrient contents in different layer decreased with soil depth (0-20 cm, 20-40 cm, 40-60 cm) increased. Soil organic matter and total nitrogen reached the peak in area with the 21-25 years restoration period and total phosphorus content reached the peak in area with the 16-20 years restoration period which indicated that the content of soil nutrient in the Loess Hilly Region can be gradually improved with low speed.
Effect of simulated grazing on carbon storage of meadow grassland ecosystem in the north slope of Tianshan Mountain
Xia Sun, Wei Ding, Hong-tao Jia, Jun-xiang Jin
2016, 10(3): 377-384. doi: 10.11829/j.issn.1001-0629.2015-0093
[Abstract](747) [FullText HTML] (59) [PDF 572KB](451)
In order to evaluate the potential effects of grazing intensity on organic carbon storage in the north slope of Tianshan Mountain meadow grassland, organic carbon storage in plant biomass, litter, root and soil were analysis in the steppes with four simulated grazing intensities (no grazing, light grazing, moderate grazing, heavy grazing) in 2012-2013. The results showed that the organic carbon storage in total, plant biomass and litter decreased with the increase of intensity. The carbon storage in root decreased in the following order: light grazing > no grazing > moderate grazing > heavy grazing and moderate grazing decreased by 42.25% and heavy grazing decreased by 72.41% compared with light grazing. The carbon storage in soil decreased in the following order: no grazing > moderate grazing > light grazing > heavy grazing. With the increase of soil depth, the carbon storage in roots gradually reduced and the changes of organic carbon density in soil varied which had an overall decline trend. The organic carbon storage in root and soil surfaced significantly. The carbon storage in the 0-20 cm soil layer account for 40% of the total carbon and the carbon storage decreased in the following order: soil > root > ground biomass. The organic carbon storage in soil was highest which account for more than 85% whereas the carbon storage in litter was the least.
Influences of white clover returning to apple orchard on soil microbial community
Qian-qian Wei, Wen-quan Yang, Ming-yu Han, Xiao-qian Mu, Jian-cun Kou
2016, 10(3): 385-392. doi: 10.11829/j.issn.1001-0629.2015-0418
[Abstract](704) [FullText HTML] (33) [PDF 688KB](527)
In order to understand the effects of burying and covering white clover (Trifolium repens) in apple (Malus pumila) orchard on the soil microbial community, the soil microbial community functional diversity was analyzed by Biolog microplate method after 1, 3 and 6 months treatments which fresh white clover was buried or covered in apple orchard by litter nylon bag, respectively. The results indicated that both covering and burying white clover could significantly elevate (P<0.05) the soil microbial metabolism activities, the microbial Shannon-Winner diversity index(except 6 months) and richness index while significantly reduced (P<0.05)uniformity index and changed soil microbial community structure. The effects of covering white clover were greater than that of burying. And the time of white clover degradation also had effects on soil microbial community. Principal component analysis of soil microbial community showed that the major differences between covering and burying were the utilization of carboxylic acids, whereas the major differences of microbial metabolism activities between degradation periods were sugars. These results indicated that both covering and burying white clover can change the soil microbial community in apple orchards, and the effects of covering were greater than that of burying.
Tissue culture and rapid propagation of Salvia hispanica
Wei-li Li, Li-fang Huang, Xin-jie Xia
2016, 10(3): 393-399. doi: 10.11829/j.issn.1001-0629.2015-0424
[Abstract](1376) [FullText HTML] (30) [PDF 979KB](465)
In order to establish the tissue culture and rapid propagation system of Salvia hispanica, the present study explored the impacts of different concentrations of hormone on callus induction, proliferation and root induction with the mature seed of S. hispanica as explant and 1/2MS as the basic medium. The results showed that the optimal medium for callus induction was 1/2MS medium with 10.0 mg·L-1 6-BA, 1.0 mg·L-1 NAA and 0.4 mg·L-1 ZT, which had the highest induction rate of 66.5%. The optimal medium for the proliferation was 1/2MS medium with 3.0 mg·L-1 6-BA and 0.5 mg·L-1 NAA, with the highest multiplication coefficient of 7.69. The optimal medium for the root induction was 1/2MS medium with 0.5 mg·L-1NAA, which had the highest root induction rate of 100% and the average rooting coefficient of 5.68. Plants grew very well after transplanting with a survival rate of 97%.
The floristic characteristics of woody plants in Anxi Nature Reserve, Gansu
Qian-yi Ding, Yang-yun Kong, Xun Pu, Ying-wen Yu
2016, 10(3): 400-407. doi: 10.11829/j.issn.1001-0629.2015-0292
[Abstract](817) [FullText HTML] (47) [PDF 460KB](442)
The exploration of the floristic geographical characteristics of woody plants in Anxi Nature Reserve will provide some scientific basis for the protection and utilization of woody plants resources in this area. In the present study, the woody plants species composition, floristic geographical characteristics and endemic species distribution in Anxi National Nature Reservation were analyzed combining the related documents, web data and the field investigation. The results showed that the woody plants species in the study area were very rich, where had 120 species of woody plants belongs to 47 genera in 21 families. There were 5 species of gymnosperms belonged to 2 genera in 2 families and 115 species of angiosperms belonged to 45 genera in 19 families; 7 species of arbor belongs to 4 genera in 3 families, 55 species of shrub belonged to 19 genera in 14 families. The floristic geographical composition of this area was complex which had 5 distributional types and 2 subtypes in the family level, 9 distributional types and 4 subtypes in the genera level, and 33 species of Chinese endemic species of woody plants. Woody plant in Anxi National Nature Reservation had an ancient origin, with some obvious the temperate component and the Mediterranean Sea component, which had a contact with the pantropic component. The woody plants in this area reflected the Mediterranean characteristics more obviously, while the herbaceous plants reflected the cosmopolitan characteristics and temperate characteristics more obvious.
The flora characteristic of seed plants in the Southern and Northern Mountains of Lanzhou
Jin-feng Xu, Hong-mei Ma, Jian-quan Zhang, Qi Chai
2016, 10(3): 408-423. doi: 10.11829/j.issn.1001-0629.2015-0273
[Abstract](949) [FullText HTML] (104) [PDF 819KB](435)
In order to understand the distribution characteristics and geographical elements of flora and fully reveal the process of natural history in the Northern and Southern Mountains of Lanzhou, the present study investigated the seed plants in this area. The results showed that the germplasm resources in the studied areas were relatively abundant which included 155 seed plant species belonging to 39 families and 115 genera in both gymnosperm and angiosperm although only 1 species in gymnosperm. The dominant families were Gramineae, Compositae, Leguminosae which were large families including 10~29 species. The middle family including 2~9 species was the main composition of flora in the study area. The families dominance was obvious and the family, genus and species of Gramineae, Compositae and Leguminosae accounted for 7.69%, 43.48% and 45.80%, respectively. The genus species distribution was loose with rich diversity and poor advantage. The geographical elements of spermatophytic families had 5 types and 4 subtypes. The dominant families in the studied area belonged to cosmopolitan which accounted for 53.85% of total families. Excepted with cosmopolitan, the tropical and temperate families were 25.64% and 6.96% of total families, respectively. The geographical elements of spermatophytic genera had 12 types and 9 subtypes. The temperate genera were dominant which accounted for 50.44% and the genera of tropical and Mediterranea accounted for 15.65% and 6.96%, respectively, which revealed that the flora in studied area had relationship with Paleo-Mediterranean flora. The composition of Central Asia and East Asia elements was weak. There was no family endemic to China and 1 genera endemic to China which was Xanthoceras. The distribution difference of germplasm resources in Southern and Northern Mountains indicated that species richness in the Northern Mountains was more abundant than that in Southern Mountains, however, the density, coverage degree, biomass, plant height, canopy and other growth indices in Southern Mountains were higher than those in Northern Mountains.
Effect of colchicines and 60Co-γ-rays on germination of Cleistogenes songorica seeds
Dai-yu Zhang, Fan Wu, Ji-yu Zhang, Yan-rong Wang, Yan Zhang, Dong Luo
2016, 10(3): 424-430. doi: 10.11829/j.issn.1001-0629.2015-0234
[Abstract](775) [FullText HTML] (90) [PDF 566KB](490)
This experiment systematically analyzed germination percentage, germination index and seedlings growth of Cleistogenes songorica with different doses of colchicine's and 60Co-γ-rays treatments. The results showed that colchicine had certain degree of inhibition on seed germination of C. songorica. With the treatment of 0.1% colchicine solution for 48 h, the germination percentage and germination index were 54.3% and 43.3% of the control which were 41% and 0.55, respectively. However, the effects of 60Co-γ-rays on germination percentage, germination index and the growth of seedlings varied with does. Low doses(50~200 Gy)increased germination percentage and germination index whereas high doses(400~2 000 Gy)inhibited the germination percentage, germination index and seedling growth. The germination percentage was 48.5% under the treatment of 600 Gy. The present study preliminary determined the semi-lethal dose treatment was 0.1% colchicine solution for 48 h and 600 Gy 60Co-γ-rays, respectively, which provided a theoretical basis for the innovation of germplasm resources in C. songorica.
Analyze the genetic variation and drought resistance of the potato germplasm
Yan Lou, Jiang-ping Bai, Hong-yu Yang, Wei-ting Li, Hui-juan Gao, Jun-lian Zhang, Di Wang, Jin-lin Zhang, Wang-tian Wang
2016, 10(3): 431-441. doi: 10.11829/j.issn.1001-0629.2015-0182
[Abstract](848) [FullText HTML] (88) [PDF 1123KB](489)
To explore the relationship between potato (Solanum tuberosum) different genetic traits and its response to water stress, we analyzed the genetic diversity of test materials by the methods of SSR, studied the content variation of peroxidase (POD and CAT) activity and soluble protein of different potato varieties under water stresses by processing potato transplanting seedling for PEG-6000 simulated water stress and natural water stress method. The results showed that the genetic similarity coefficient (GS) at 0.700 level, 44 potato materials can be divided into five types, most breed clustered together, explaining the genetic basis of testing varieties is still relatively narrow. Through a GGE-biplot comprehensive analysis of soluble protein, POD and CAT variation, 44 selected materials were divided into 6 groups. Comparative analysis of genetic diversity analysis and physiological results found that there were no obvious consistency between them, namely the species differences in genetic traits can't react their drought resistance performance difference directly. But two stress modes with high consistency on studying the characteristics of varieties of drought resistance. This research provides the reference for further drought resistance research.
Effect of CO2 enrichment on hormone content of different types fall dormancy alfalfa
Xiao-meng Zhai, Chun-xin Zang, Min Wang, Meng-yun Ren, Xiao Guan
2016, 10(3): 442-449. doi: 10.11829/j.issn.1001-0629.2015-0396
[Abstract](793) [FullText HTML] (48) [PDF 699KB](397)
To investigate the effects of elevated CO2 on endogenous hormone content of three different fall dormancy alfalfa(Medicago sativa) cultivarsfor the entire growth period of alfalfa processing under three different CO2 concentration gradient (700 μmol·mol-1, 550 μmol·mol-1 and normal atmospheric CO2 concentration 350 μmol·mol-1). The results of measured in each growth stage leaves endogenous hormone showed that: the higher CO2 concentration, the higher auxin (IAA), gibberellin (GA3), the lower content of abscisic acid (ABA) contentin .The IAA/ABA and GA3/ABA of the alfalfa increased by high CO2 concentration handling throughout whole growth period, also, high CO2 concentrations was conducive to the lifting of dormancy alfalfa, maintaining growth. Meanwhile, high CO2 concentrations had a significant effect (P<0.05) of endogenous hormones alfalfa when early flowering and flowering. It was most favorable for growth and development of semi Alfalfa, then the non-fall dormancy alfalfa when the air CO2 concentration increased. The fall dormancy of fall dormancy Alfalfa decreased and the growth period was prolonged in the treatment of high CO2 concentration.
Relationship between leaf morphology and physiological responses of perennial ryegrass under cold stress
Bi-hui Sun, Rong-quan Li, Xiao-chun Duan, Zhi-hui Chang
2016, 10(3): 450-458. doi: 10.11829/j.issn.1001-0629.2015-0430
[Abstract](931) [FullText HTML] (57) [PDF 746KB](502)
Perennial ryegrass(Lolium perenne) is susceptible to cold and windy condition in winter, which results in dehydration and death. In order to explore the relationship between leaf morphology and physiological changes of perennial ryegrass under cold stress, leaf morphology, relative water loss rate of detached leaves and some physiological indices under cold stress 0 ℃ of cultivar 'Brightstar SLT' (freezing-tolerant) and 'Linn' (freezing-sensitive) were measured. Under natural condition, the stomatal number of 'Brightstar SLT' was significantly higher than (P<0.05) that of 'Linn', whereas stomatal length, stomatal area, leaf epidermal cell and leaf relative water loss of 'Brightstar SLT' were significantly lower than (P<0.05) those of 'Linn'. Under cold stress, transpiration rate and stomatal conductance of both perennial ryegrass cultivars increased in a short time, however, those of the 'Brightstar SLT' were significantly lower (P<0.05) than those of 'Linn'. In addition, the photosynthetic rate of 'Brightstar SLT' was significantly higher (P<0.05) than that of 'Linn', whereas electrolyte leakage of 'Brightstar SLT' was lower than that of 'Linn'. In conclusion, there was a close correlation between lower water loss rate along with better performance under cold stress (including stable photosynthesis ability and less cold injury) and leaf morphology (including larger quantity of stoma, shorter stomatal length, smaller stomatal size and smaller leaf epidermal cell) in freezing-tolerant cultivar.
The production characteristics of Sophora alopecuroides populations in different habitats
Zhi-chao Fan, Yan-rong Wang
2016, 10(3): 459-470. doi: 10.11829/j.issn.1001-0629.2015-0251
[Abstract](915) [FullText HTML] (89) [PDF 900KB](370)
In order to compare the production characteristics of Sophora alopecuroides from arid and moist habitats, the indices including herbage yields, seed yields, seed sizes and hard seed rates were measure for the samples from five positions in main distribution areas including Linze County and Minqin County, Gansu Province; Yanchi County, Ningxia Province; Left Banner and Ejina Banner of Alxa League, Inner Mongolia. The results showed that environments greatly affected the production characteristics of S. alopecuroides. The forage yield per branch (4.9 g) in arid habitats was less than that (7.2 g) in moist habitats. The average forage yield per unit area was 1 330.7 kg·ha-1 in arid habitats and 1 546.1 kg·ha-1 in moist habitats. The seed yields per area and branch, harvest indexes, hard seed rates and thousand seed weights in arid habitats were all higher than those in moist habitats. The average actual seed yield and harvest index were 335.0 kg·ha-1, 1.2 g per branch and 17.0% in arid habitat, which were significantly increased (P<0.05) by 2.2, 1.7 and 2.1 times than those in moist habitat. The average rate of hard seed in arid habitat was 91.0% which was 5.7% higher than that in moist habitat. The average thousand seed weight was 19.5 g in arid habitat, which was 1.3 times of that in moist habitat. In both two habitats, the fertile shoots density and seeds per pod had greatly significant correlations (P<0.01) with seed yield per unit area. The nationwide herbage yield of S. alopecuroides was estimated to be 2 395 000~2 783 000 tons and the seed yield was estimated to 278 000~603 000 tons based on the measured data.
Comparative test of three orchardgrass cultivars (lines) in Ya'an, Sichuan
Sheng-ting Yang, Ming Zhong, Qian Ban, Xin-quan Zhang, Lin-feng Jiang, Peng Hu, Wei-ping Ma, Lin-kai Huang
2016, 10(3): 471-478. doi: 10.11829/j.issn.1001-0629.2015-0412
[Abstract](798) [FullText HTML] (53) [PDF 559KB](380)
To explore the discrepancies among several different orchardgrass (Dactylis glomerata) cultivars (lines), cultivars comparative tests were conducted with three orchardgrass cultivars (lines) in Ya'an from 2012 to 2014. The results showed that 'Baoxing' and 'Dianbei' were early-maturing, while 'Aldebaran' was late-maturing which can be used for longer time. 'Dianbei' had the highest yield of 11 443 kg·ha-1 in 2013, while 'Baoxing' had the highest yield of 8 101 kg·ha-1 in 2014. In 2013, the yields of 'Aldebaran' had significant difference with the yields of 'Baoxing' and 'Dianbei' (P<0.05), although the latter two had no significant difference (P>0.05). In 2014, there was no significant difference among these three cultivars (lines). Comparing with other two cultivars, 'Aldebaran' had the lowest stem-leaf ratio, indicating rich leaves. The results of nutrients analysis showed that the rank of protein content from high to low was 'Aldebaran' (21.63%), 'Dianbei' (20.70%), and 'baoxing' (20.37%), and the crude protein content of 'Aldebaran' exceeded 'Dianbei' and 'Baoxing' by 0.93% and 1.26%, respectively. In summary, 'Aldebaran' had better quality than 'Baoxing' and 'Dianbei'.
Research progress on influencing factors of seedling establishment
Wei-zhen Zhang, Zhong-kuan Liu, He-jing Zhao, Gui-xia Liu
2016, 10(3): 479-488. doi: 10.11829/j.issn.1001-0629.2015-0059
[Abstract](747) [FullText HTML] (22) [PDF 637KB](489)
Seedling establishment is the results of successful seed germination and seedling survival, which is the vulnerable and key stage of plant life cycle. A variety of factors might affect the survival of seedlings and then influence the distribution and abundance of the plant in the community. The present study discussed the concept of seedling and seedling establishment and summarized the effects of light, temperature, soil water regime, heterogeneous habitat, microhabitat, predation and digestion by animals and plant reproduction characters, litter, the pathogen and allelopathy on seedling establishment according to relative researches from home and abroad. This review will provide theory basement for further understanding the regeneration process of vegetation community and mechanism of community succession.
Effect of three grass combinations on the nitrate reduction in rumen fluid of Hu sheep
Meng-qi Wang, Zhi-yuan Chen, Ting-ting Ma, Miao Lin
2016, 10(3): 489-494. doi: 10.11829/j.issn.1001-0629.2015-0212
[Abstract](875) [FullText HTML] (51) [PDF 477KB](329)
A 3 × 3 Latin square design was used to investigate the effect of feeding Leymus chinensis or equal proportion of alfalfa hay (Medicago sativa) and oat grass (Avena sativa) on dynamic changes of nitrate nitrogen content and fermentation characteristics of Hu sheep. Rumen fluid was obtained at 0, 1, 2, 3, 4, 5 and 6 h after feeding to determine the concentration of nitrate and nitrite and fermentation parameters. Blood samples were collected at 2 h after feeding to determine the blood methemoglobin content. The results showed that, 1) the concentrations of nitrate and nitrite in rumen fluid increased to the maximum level at 1 and 2 h after feeding, respectively, and then decreased rapidly. 2) There was no significant difference in the pH value and percentage of nitrate and nitrite among groups (P>0.05); however, ammonia nitrogen (NH3-N) concentration in group A was significantly lower than that in the other groups (P=0.018). 3) All the groups had a low concentration of blood methemoglobin, and no significant difference was observed among them (P>0.05). In conclusion, different grass combination in this study had no effect on nitrate reduction process in the rumen of Hu sheep.
The characteristics of soil fauna communities in three forest-grass patterns in Deyang, China
Tao Wu, Mao-song Feng, Dong-miao Han, Wen-bing Li, Lie-hua Tie
2016, 10(3): 495-502. doi: 10.11829/j.issn.1001-0629.2015-0421
[Abstract](723) [FullText HTML] (41) [PDF 535KB](360)
This study was conducted to study the composition and community structure of soil fauna in three types of forest-grass patterns (Juglans regia+Medicago sativa, Cichorium intybus and Dactylis glomerata), and a pure Juglans woodland was applied as a control group in Deyang, Sichuan Province. The results showed that, A total of 303 specimens of soil faunas was found in this study, which were belonged to 3 phylum, 7 classes and 17 orders. Of those, Nematoda, Hymenoptera and Acarina were the dominant groups. The soil fauna was found to gather on the surface of earth in three types of forest-grass pattern, while the order of soil fauna density was 5-10 cm>10-15 cm>0-5 cm. In addition, the diversity of Shannon-Wiener index and DG (Density-groups) index of soil fauna was the highest in the J. regia+M. sativa pattern while the lowest DG index in pure woodland that possessed the highest Pielou index; The J. regia+M. sativa pattern has a significant difference to the pure woodland pattern in individual number of soil fauna, but on the area of species of groups are similar to the pure woodland pattern, and it had a highest proportion of Saprozoic fauna in four patterns. In summary, the three forest-grass patterns can enrich the composition of soil fauna communities, and highest abundant soil fauna was observed in J. regia+M. sativa pattern.
The biological functions of phytogenic polysaccharides as feed additives
Yu-huai Xie, Qing-hui Shang, Gulimeina, Ying-nan Wang, Chong-yu Zhang, Wei-ren Yang, Gui-guo Zhang
2016, 10(3): 503-511. doi: 10.11829/j.issn.1001-0629.2015-0433
[Abstract](1110) [FullText HTML] (50) [PDF 816KB](519)
Phytogenic polysaccharides are a class of active materials with various biological functions. They have been widely applied in livestock breeding as functional feed additives, which promote growth, strengthen immunity, improve bowel health and product quality. This paper summarized the research progress on the biological functions and working mechanisms of phytogenic polysaccharides, and explained the application effects as well as existing problems in livestock farming breeding, to provide a good reference for further exploration in this research area.
Evaluation of mixing silage of Musa paradisiaca stems and leaves and Stylosnthes guianensis
Sha Jin, Shi-zhang Huang, Yi Zhong, Meng-di Liang, Tao Chen, Xue-mei Wang
2016, 10(3): 512-518. doi: 10.11829/j.issn.1001-0629.2015-0505
[Abstract](682) [FullText HTML] (30) [PDF 520KB](376)
This experiment was excuted to exploit the quality of fermentation of mixed Musa paradisiaca stems and leaves and Stylosnthes guianensis. Four treatment groups were set according to the proportion of S. guianensis, 100% M. paradisiaca stems and leaves, 100% S. guianensis, 75% banana stems and leaves with 25% S. guianensis, 50% M. paradisiaca stems and leaves and 50% S. guianensis, each treatment contains 3 replicates. After 5 weeks of fermentation, the sensory evaluation and laboratory test of silage were carried out. The results showed, 100% M. paradisiaca stems and leaves group got the best quality in sensory evaluation, 100% S. guianensis group got 6 in sensory evaluation, the lowest in all groups, mixed silage groups were in the middle of all groups, the quality of mixed silage were evaluated with the growing ratio of banana stems and leaves. The 100% M. paradisiaca stems and leaves group got the lowest pH value, with the rising ratio of S. guianensis, the value of pH (P<0.01) and the colony count of lactobacillus (P<0.05) were improved. The acetic acid of 100% S. guianensis group was the lowest, no significant differences were observed in the lactic acid and butyric acid of all groups(P>0.05), no significant differences in fermentation quality due to the content; 75% M. paradisiaca stems and leaves and 25% S. guianensis group improved the content of lactic acid and acetic acid and the colony count of lactobacillus. With the improving ratio of S. guianensis, the content of water and water soluble carbohydrates (WSC) were depressed(P<0.05), the content of crude protein and crude fiber were improved significantly(P<0.05). With the sensory evaluation and laboratory tests, mixture of M. paradisiaca stems and leaves and S. guianensis reduced the water content, increased the content of WSC of S. guianensis, improved the quality of fermentation of mixed silage, and the best quality is 75% M. paradisiaca stems and leaves and 25% S. guianensis.
Ultrasonic-enzyme synergistic extraction and antioxidant activity analysis of alfalfa polyphenols
Wei-mei Shi, Long-huo Wu, Xiang Yang, Sha Yang
2016, 10(3): 519-526. doi: 10.11829/j.issn.1001-0629.2015-0419
[Abstract](789) [FullText HTML] (55) [PDF 637KB](351)
The polyphenols from alfalfa were extracted by ultrasonic-enzyme synergistic method. The effects of liquid-solid ratio, enzyme addition volume, enzyme incubation time, ultrasonic time, ultrasonic temperature and pH on phenol yield of alfalfa were investigated, and the extraction technology was optimized by response surface experiment. The antioxidant activities of alfalfa phenols were also studied. The results showed that the optimum technology factors for extracting alfalfa phenols were as follows: enzyme addition was 4.9%, ultrasonic time was 74 min and ultrasonic temperature was 49 ℃. Under this condition, the highest extraction quantity of total phenols could reach 3.642 mg·g-1. In addition, the phenols showed strong activities for DPPH (2,2-diphenyl-1-picrylhydrazyl) and hydroxyl radical scavenging, and the half scavenging concentration (IC50) of DPPH and ·OH radicals were 10.78 μg·mL-1 and 19.28 μg·mL-1, respectively.
Trend, lessons and enlightenment of the alfalfa trade in the United States
Wu-jing Wang, Ming-li Wang, Guan-wang Lyu, Yu-feng Liu, Zi-zhong Shi
2016, 10(3): 527-534. doi: 10.11829/j.issn.1001-0629.2015-0397
[Abstract](1055) [FullText HTML] (150) [PDF 603KB](452)
With the rapid transformation of Chinese dairy industry and other grass-feeding livestock industry, the demand of high-quality alfalfa imported from the United States has been increased fast. As a new industry developed in recent years, Chinese alfalfa industry could not meet the huge market demand. The study on the international market trade of the United States can be effectively useful to catch up with the development of international standards. The United States is the most powerful country of alfalfa production and trading, it is of great value to analyze the alfalfa trade trend and sum up the trade experience. The findings indicate that the export quantity of alfalfa produced in the United States has been gradually increased, and the export price has been risen as well. The main experiences are as follows: 1) High standard and strict alfalfa product quality are prerequisite to protect alfalfa exports; 2) High-level marketing strategy is an important driving force to promote the export; 3) Powerful information traceability system is key means to ensure alfalfa quality; 4) Low-cost transportation system is a critical condition to enhance the export competitiveness of alfalfa. For the purpose of enhancing alfalfa industry competitiveness, Chinese government should attach importance to alfalfa international trade market, improve marketing strategy, complete the secondary compression technology, regulate industrial entities, and build grass product quality tracibility system.
Plant and animal farming development in the southwest China
Hui-lian Cen, Qi-lin Tang
2016, 10(3): 535-539. doi: 10.11829/j.issn.1001-0629.2015-0378
[Abstract](1053) [FullText HTML] (125) [PDF 352KB](417)
This study analyzed farming, animal husbandry and aquaculture proportional changes in Southwest China. Data referring to aquaculture and the Southwest forage crops from 1981-2012 were obtained from "China Agriculture Yearbook Database". The aim of the study is to provide a scientific basis for the development of forage crop area by adjusting the structure. Results show that the grain-oriented cash crops are the predominant agricultural industry in Southwest China, pigs are the main livestock and grazing livestock is in the steadily growth.
The laboratory proficiency test system of International Seed Testing Association and its implication for herbage seed in China
Yan Sun, Pei-sheng Mao
2016, 10(3): 540-546. doi: 10.11829/j.issn.1001-0629.2014-0537
[Abstract](886) [FullText HTML] (74) [PDF 479KB](404)
The definition and significance of the laboratory proficiency test (PT) were stated in this paper. The programme, scope and the results evaluation method of PT of International seed testing association (ISTA) were introduced. The current situation and problems of herbage seed testing in China were described, and some suggestions for establishing and improving the laboratory PT system of China were given.
The potential of research assistant in undergraduate teaching in pratacultural science ----A case study of Gansu Agricultural University
Jun-hu Su, Shang-li Shi, Jing Yang, Yu-kun Kang, Kai Du
2016, 10(3): 547-552. doi: 10.11829/j.issn.1001-0629.2015-0291
[Abstract](741) [FullText HTML] (77) [PDF 487KB](635)
Talent training is the fundamental mission of colleges and universities. Innovation in undergraduate teaching at a university, and exploring for more effective mode of teaching are very important for improving education system and education quality at the tertiary level. In this paper, taking the undergraduate students in pratacultural science as an example, the undergraduate "research assistant" model and its positive role in improving student learning were analyzed, and its operating mechanism and the implementation were summarized. This paper aims to strengthen the training effect of "research assistant" training model for colleges and universities, and provide professional reference for tertiary education and other professional trainings.