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2015 Vol.32(8)

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2015, 9(8): 0-.
[Abstract](1314) [PDF 1990KB](361)
2015, 9(8): 1201-.
[Abstract](922) [PDF 401KB](436)
Distribution characteristics of Epichloё endophyte in gramineous grasses
Xiao-jing ZHAO, Ping WANG, Xiu-zhang LI, Li-jun GU, Chun-jie LI
2015, 9(8): 1206-. doi: 10.11829/j.issn.1001-0629.2014-0393
[Abstract](1109) [PDF 8308KB](465)
In the present study, the internodal region of stems, sheaths, blades and seeds of four different species including Achnatheru inebrians, Festuca sinensis, Hordeum brevisubulatum and Elymus dahuricus were observed by the light microscopy and transmission electron microscopy. The results showed that Epichloё endophyte distributed in all these four tested tissues in each species. The endophyte distribution characteristics in these 4 different species were similar, which included hyphae densely distribution in the internodal region of stems and followed by sheaths whereas sparse distribution in blades. The hyphae were straight or curved and long, thin and unbranched and longitudinally growth in the cell extension direction. In the seeds, Epichloё endophyte hyphae were widely distributed in the aleurone layers of F. sinensis, H. brevisubulatum and E. dahuricus, however, it was sparely distributed in the aleurone layers of A. inebrians. Epichloё endophyte hyphae were also observed in the seed coats and embryos of these four gramineous grasses.
Effects of alfalfa root exudates on insoluble phosphorus in soil
Li-ning YANG, Aotegen·baiyin, Qiu-feng LI, Yan-xia GAO, Min-yun XU, Jin-hua FENG, Yun-qi LI
2015, 9(8): 1216-. doi: 10.11829/j.issn.1001-0629.2014-0607
[Abstract](1153) [PDF 461KB](433)
The root exudates of 6 alfalfa cultivars including Zhongmu No.1, Target, TG3, Knight 2, Knight T and Adina growing in hydroponics with phosphorus or without phosphorus were collected to investigate their activation of insoluble phosphorus and effects on P effectiveness in soils. Compared with the soils without root exudates, the contents of effective P (OlsenP) increased, the contents of Ca2P extremely significantly decreased (P<0.01), the contents of AlP、FeP and Ca8P significantly decreased (P<0.05) and the contents of OP and Ca10P did not change in soils treated with root exudates(P>0.05). The activation of insoluble phosphorus of root exudates from plants without P was better than that of root exudates from plants with P. The contents of Ca2P had the largest decline in soil treated with TG3 root exudates with the highest P effectiveness. The contents of Ca8P had the largest decline in soil treated with Knight T root exudates with the secondly P effectiveness. Alfalfa root exudates have activation on AlP, FeP, Ca8P, Ca2P and especially for Ca2P which was the largest source of OlsenP under phosphorus deficiency condition.
Changes of community characteristics in the degradation process of the alpine swamp wetland in the Yellow River Source area
Guo-hua REN, Bin DENG, Yuan HOU
2015, 9(8): 1222-. doi: 10.11829/j.issn.1001-0629.2015-0272
[Abstract](1133) [PDF 644KB](494)
Based on the method of replacing time series with spatial sequence, the changes of plant community spatial distribution characteristics in the degradation process of the alpine swamp wetland were investigated in the Yellow River Source area in QinghaiTibetan Plateau of China. The results showed that the degradation process of the wetland experienced from swamp meadow to alpine meadow, and to degraded grassland. During this progress, the species component in plant communities had succession and hygrophytes were replaced by mesophytes and xerophytes, the dominant plants, Kobresia tibetica, gradually disappeared and forbs became constructive species. Species richness index, evenness index and diversity index firstly increased and then decreased whereas dominance index inversely decreased and then increased which peaked at the alpine meadow stage. As the succession proceeded, the aboveground biomass showed a unimodal decreased curve, the proportion of perennial forbs increased dramatically and the speciesabundance distribution gradually changed into a ZipfMandelbrot model from the early lognormal model.
Assessment of soil fertility in lucerne stands of different ages using grey correlative degree analysis
Zhen-nan WANG, Qing-ping ZHANG, Jiao-yun LU, Mei YANG, Hui-min YANG
2015, 9(8): 1230-. doi: 10.11829/j.issn.1001-0629.2014-0473
[Abstract](961) [PDF 452KB](387)
Soil fertility reflects the performance and growth potential of plant which is easily affected by the plant. In the perennial grasslandecosystem, the effect of forage age on the soil fertility has not been clearly elucidated yet. In the present study, the soil fertility in lucerne stands with six different ages were comprehensively analysed using grey correlative degree analysis to evaluate the effect of stand age on soil fertility. In different soil layers, the contents of organic carbon, total nitrogen, ammonium, nitrate, total phosphorus, available phosphorus and total potassium were different in different lucerne stands cultivated in different years, and they differently varied with stand age. Using grey correlative degree analysis, the best soil fertility was observed in 5year old stands in 0-10 and 10-20 cm soils, the best soil fertility was observed in 8year old stands and the better soil fertility was observed in 5year old stands in 20-30 cm soils. Conclusively, in the Loess Plateau, the optimal utilisation age of lucerne was 5year old considering soil fertility.
Cloning of SAMDC gene from Festuca arundinacea Qiancao No. 1 and construction of its plant expression vector
Qing-fei ZENG, Chun-yan YANG, Xiao-dong LI, Jia-hai WU, Xiao-li WANG
2015, 9(8): 1237-. doi: 10.11829/j.issn.1001-0629.2014-0573
[Abstract](961) [PDF 619KB](404)
SAMDC gene was amplified from cDNA of Festuca arundinacea Qiancao No. 1 leaves and DNA sequencing analysis indicated that the amplified fragment contained 1 835 nucleotides, which involved a tiny upstream open reading frame(ORF) of 9 bp, a small upstream ORF of 147 bp and a main ORF of 1 185 bp encoding 395 amino acids. There was one overlap base between the tiny upstream ORF and the small upstream ORF. The homology between the cloned fragment and the FaSAMDC gene of Festuca arundinacea registered in GenBank was 95.05% and the homology of their encoded amino acid was 98.22%. This cloned fragment was inserted into modified plant expression vector pCAMBIA1300 with multiple cloning sites using the KpnI and PstI enzyme. The plant expression vector pCAM-SAMDC with genes of SAMDC and hygromycin resistance was obtained by agarose gel detection, restriction enzyme digestion and sequencing which was suitable for monocotyledons genetic transformation. The recombinant plasmid was transmitted into Agrobacterium tumefaciens component cells GV3101 and EHA105 and the positive clone was selected by PCR. These works laid a foundation for further stress tolerance Poaceae grass via Agrobacterium-mediated method.
The research of growth curve for monoculture and mixture planting crops grown under different density conditions
Jia-wei GUAN, Ming-fei JI, Zhi-qiang WANG, Zhe-xuan FAN, Jin-zhi RAN, Jian-ming DENG
2015, 9(8): 1243-. doi: 10.11829/j.issn.1001-0629.2015-0373
[Abstract](1032) [PDF 535KB](402)
According to metabolic scaling theory (MST), plant metabolic rate is nearly isometric to body size (biomass) for seedlings and samplings, and the scaling power is convergent to a constant 3/4 with the increasing plant size. Recently, we developed the dynamic growth model of individual sampling and seedling based on MST. However, plant individual which grown under intraspecies or interspecies competition pressure, will be strongly affected by the neighbors competition during development, it's unclear whether the growth model is suitable to the plant individuals with different pressure from intra and interspeciesneighbor competition. Therefore, three crops including spring wheat, flax, corn were selected and planted by monoculture and pair combination mixture cultivation ways, with three originally sowing densities(i.e. high, middle and low densities). We tracked the dynamic growth of individual plants in each plot for six times from germination to mature period including plant height, caudex, canopy and biomass. After fitting the growth curves based on the dynamic growth model proposed by Deng et al.(2012),we found that the growth curvesof plant individuals conform to the modelregardless of density gradient and planting way. However, the plant grows better and has bigger mature size for the species with similar nichesand in mixture cultivation plots than that in monoculture cultivation plots. Furthermore, and the growth rates and mature sizes decrease with the increasing densities or competition intensities for all species and planting ways. In a word, although the growth rate and mature size of plant vary with the competitive pressureof neighbors, growth curves of plant individual is still conformed to our growth model under different intra and interspeciescompetitive pressure. In current paper, we not only examined the growth model of small plant and the metabolic scaling theory, but also further pushing the development of metabolic theory.
Effects of salt stress on germination characteristics of Agropyron mongolicum and salttolerance evaluation
Lu-lu ZHOU, Bing-zhe FU, Dong-mei XU, Li-ping CHEN, Xiao-juan WU, Xue-qin GAO
2015, 9(8): 1252-. doi: 10.11829/j.issn.1001-0629.2014-0569
[Abstract](1038) [PDF 548KB](405)
The germination characteristics of 7 wild ecotypes of Agropyron mongolicum from different areas and cultivar Mengnong No. 1 under different NaCl concentrations(0.00%, 0.30%, 0.60%, 0.90%, 1.20%)were measured and salt tolerance performances were comprehensive evaluated by membership function. The result showed the salt stress had obvious inhibition on each index because the germination percentage, germination potential, germination index, vitality index and relative seedling length and root length obviously decreased with the increase of salt stress. Light salt stress (0.30% and 0.60%) promoted radicle growth for some materials and heavy salt stress (0.90% and 1.20%) strongly inhibited radicle growth for all these 8 germplasms. Based on the membership function method, the salt stress tolerance of these studied 8 germplasms decreased in the following order: Fengjigou No.7 Xinzhuangji No.5 Maerzhuang No.4 Yehujing No.3 Sidunzi No.1 Sidunzi No.2 Agropyron mongolicum cv. Mengnong No.1 Luoshan protection No.6. Thus, the germplasms from Fengjigou had stronger salt tolerance and the germplasms from Luoshan natural reservation had weaker tolerance.
Effects of ethephon soaking seeds on growth of Lolium perenne seedlings at different soil moistures
Li SU, Di DONG, Qi CHAI, Jian-quan ZHANG, Fei-ji CEN, Qun YU, Hong-mei MA, Jia-ning WEI, Mei YANG
2015, 9(8): 1260-. doi: 10.11829/j.issn.1001-0629.2014-0424
[Abstract](968) [PDF 616KB](517)
The present study evaluated the growth performance of perennial ryegrass (Lolium perenne cv. Accent) at seedling stage response to ethephon soaking treatment under different soil moistures treatments. Three different soil water contents (30%, 50% and 70% of maximum field water capacity, FWC) were set to simulate the severe dry, moderate and moist soil condition. Meanwhile, the seeds were soaked with 4 different concentrations of ethephon solution (control,0.05%,0.1% and 0.2%) for 24 hours before planting. The results indicated that FWC 30%~50% were the ideal soil water contents for perennial ryegrass growth which did not need too much irrigation. The concentrations of 0.05%~0.1% ethephon concentration could reduce the effects of soil water content on perennial ryegrass growth. However, soil water content had major impacts on perennial ryegrass growth compared with ethephon soaking.
The analysis of stable isotope value, chlorophyll and nutritional quality of Leymus chinensis
Tian MA, Jing MENG, Dong-mei QI, Gong-she LIU
2015, 9(8): 1268-. doi: 10.11829/j.issn.1001-0629.2014-0577
[Abstract](1130) [PDF 598KB](482)
The stable isotope value (13C), chlorophyll (SPAD) value and main nutrients of different varieties of Leymus chinensis which were planted in 3 different types of soils were determined and the correlation and regressions between these indices were explored and discussed. The results showed that the effects of the soil on 13C and SPAD values of L. chinensis varieties BG2 and B were high significant (P0.01), while the effect on the SPAD value of the varieties Y1 were not significant. The correlations between the 13C values of L. chinensis and the soil organic matter(SOM), available nitrogen (AN), total salt content (TS) and water content (WC) ranged from 0.737 to 0.800 (P<0.01). In addition to that the regression relationship of the 13C value of L. chinensis with the total salt content of the soil was significant(P<0.05), its regression relationships with the other measured soil factors were all high significant(P<0.01). The correlations indices between the 13C values (-28.613~-27.383)and the crude protein(CP), crude fiber(CF) and lysine were 0.533, 0.591 and 0.401 respectively and the regression relationships were significant. The correlations with the indispensable amino acid (IAC) and energy content were 0.469 and 0.649, respectively and the regression relationships were significant. The correlations between the SPAD values of L. chinensis and the CP, neutral detergent fiber, phosphorus, crude ash and dry matter (DM) content were relatively high with the correlation indices ranging from 0.596 to 0.783. The correlation between the SPAD values(37.075~42.893) and the proline was the highest (R2=0.902, P<0.01). The correlations between the SPAD values and the total amino acid (TAA) content and IAC content ranged from 0.833 to 0.887 and the regression relationships were both high significant. These tested indices performed significant regression relationship. In conclusion, the SPAD value was the best index to suggest the nutrition quality of L. chinensis. The Y1 and Y3 varieties of L. chinensis should be widely cultivated as they had relatively high SPAD value, DM, CP, energy content, the proportion of TAA and IAC and relatively low CF content.
Effects of heavy metal cadmium on morphology and physiology of Festuca arundinacea seedlings
Jin FAN, Qing-hua YUAN
2015, 9(8): 1278-. doi: 10.11829/j.issn.1001-0629.2014-0579
[Abstract](947) [PDF 560KB](479)
A comprehensive evaluation of 20 Festuca arundinacea cultivars tolerance to heavy metal cadmium (Cd) was conducted by measuring their morphological and physiological response under different Cd2+ concentrations. The results showed that survival rate, plant height, above ground biomass and leaf water content significantly decreased with the cadmium concentration increasing whereas tiller numbers firstly increased and then decreased with the cadmium concentration increasing. Two strong cadmium tolerant cultivars(M15 and M8) and two weak cadmium tolerant cultivars (M5 and M11) were screened using the standard deviation coefficient allocation weight method. And then, the physiological response of these 4 cultivars to Cd2+ including the activities of peroxidase (POD) and catalase (CAT) and the contents of chlorophyll and proline (Pro) were measured. With the cadmium concentration increasing, the activities of POD and CAT of 2 strong cadmium tolerant cultivars increased whereas those of 2 weak cadmium tolerant cultivars firstly increased and then decreased. With the cadmium concentration increasing, the chlorophyll contents of all tested cultivars decreased and Pro contents of all tested cultivars increased.
Study on introduction of Galega orientalis cv. Xinyin No.1 to Xining area
Shu-juan LI, Chang-hui LI, Ying ZHANG, Yong-peng TANG, Xiu-jin LIANG
2015, 9(8): 1289-. doi: 10.11829/j.issn.1001-0629.2015-0487
[Abstract](729) [PDF 488KB](354)
Based on the special natural conditions in Qinghai Province and the shortage of leguminous forage grass, the good forage variety Galega orientalis cv. Xinyin No.1 was introduced from Xinjiang and the following cultivation and evaluation were conducted. The results showed that Xinyin No.1 can finish life cycle and normally fruit and rapidly grow which had hay yield of 13 414 kgha-1, crude protein content of 20.28% at the squaring period, stemleaf ratio of 1∶1.58 and overwintering rate of 100%. These results suggested that Xinyin No.1 had good cold resistance, fast growth, high nutritional value and strong adaptability which can meet the demands of Xining regions. The experiment provided scientific basis for choosing and utilizing good leguminous forage grass varieties, and provided excellent grass varieties for the development of forage industry in Xining and similar stockbreeding areas.
Evaluation of Vicia sativa germplasm resources in Gausu
Bing-lin LU, Xing-guo BAO, Jiu-dong ZHANG, Xin-qiang YANG, Wei-dong CAO
2015, 9(8): 1296-. doi: 10.11829/j.issn.1001-0629.2014-0372
[Abstract](1167) [PDF 461KB](413)
In the present study, germplasm resources of 42 Vicia sativa varieties were evaluated to screen optimal V. sativa varieties for planting green manure in Gausu. Results showed that there were obvious differences in the tested trait indices of germplasm resources of 42 V. sativa, in which pods per plant and grains per plant were the main elements of V. sativa production. Four indices including grain yield, fresh yield, grains per plant and pods per plant indicated characteristics of V. sativa which can clustered these 42 varieties into four groups. Seven varieties belonged to groupⅠ and groupⅡ which had grain yield and fresh yield of 2 623.26~2 990.25 and 32 357.70~35 967.38 kgha-1, respectively. Sujian 3, Longjian 1 and 333/A belonged to early maturing varieties which were optimal for five culture including intercropping and multiple cropping after wheat crops harvest, early maize intercropping, green manure intercropped with potato, green manure intercropped with fruit tree and green manure monocropping. Shanxi spring V. sativa and MB5/794 belonged to midmaturing varieties which were optimal for intercropped with potato, and fruit tree and monocropped. Ximu 820 and Polish Vicia sativa belonged to latematuring varieties which were optimal for intercropped with fruit tree and monocropped.
Production performance and nutrient contents evaluation of the different Leymus secalinus populations from Shanxi
Peng-peng FAN, Li-xia DU, Ya-di HUO, Kuan-hu DONG
2015, 9(8): 1303-. doi: 10.11829/j.issn.1001-0629.2014-0608
[Abstract](1031) [PDF 483KB](258)
In order to provide theoretical basis for reasonably selecting and utilizing the genetic resources of Leymus secalinus, eight populations of L. secalinus from Shanxi Province were cultivated at Taigu, Shanxi. Production performance and nutrient contents of these populations were evaluated. Except with the numbers of fertile stems, spikelets, florets and seeds, seed reproduction traits including spike length, ripening rate and weight of 1 000 seeds were significantly different (P<0.05) among populations. The principal component analysis of seed reproduction traits showed that the first 3 principal component factors were spike length, floret and fertile stems and the cumulative contribution rate was up to 81.09%. The principal component analysis of nutrient contents showed that the first 3 principal component factors were crude protein, crude fat and crude ash and the cumulative contribution rate was 87.89%. The comprehensive analysis indicated that the production performance and nutrient contents of populations from Youyu and Hunyuan were the best, which could be used for breeding in the future.
Effects of CO2 and illumination on wheat grain yields based on APSIM model
Juan-juan LEI, Li-juan YAN, Guang LI, Li-xia DONG, Zhen-ni GAO
2015, 9(8): 1310-. doi: 10.11829/j.issn.1001-0629.2014-0389
[Abstract](1023) [PDF 500KB](454)
In order to explore the effects of illumination intensity and CO2 concentration on wheat (Triticum aestivum) grain yield, the grain yield under different illumination intensities and CO2 concentrations was simulated by validated Agricultural Production System Simulator Model(APSIM) and cooperation factors were analysised by multiple regressions. The results showed that the grain yield rapidly decreased with the increase of illumination intensity under the same CO2 condition which had maximum grain yield losses of 17.16% and the average grain yield losses of 9.40% with the light intensity increased by 0.5 MJm-2. The grain yield increased with the increase of CO2 condition under the same illumination intensity which had maximum grain yield losses of 22.08% and the average grain yield losses of 11.27% with the CO2 concentration increased by 100 molmol-1. There was negative interaction between light intensity and CO2 concentration which suggested the local environment was suitable for wheat growth.
Effects of sheep wintering grazing on growth and yield of winter wheat
Fei LI, Xiu-zhen ZHANG, Xian-ru GAO
2015, 9(8): 1317-. doi: 10.11829/j.issn.1001-0629.2014-0374
[Abstract](1072) [PDF 446KB](309)
In order to evaluate the effect of sheep wintering grazing on growth and yield of winter wheat (Triticum aestivum), the soil water, tiller number, plant height, forage yield and seed yield of winter grazed wheat and nongrazed wheat as control were observed in a rainfed region of the Loess Plateau. The results showed that the green forage yield and dry weight of winter wheat in wintering were 4.68 and 1.35 tm-2, respectively. After winter grazed, soil water in 10-20 cm soil layer increased by 1.13% at returning green stage and the tillers of winter grazed wheat was 5.5 per plant at standing stage which significantly increased by 19.6% compared to nongrazed winter wheat (4.6 per plant). The height of winter grazed wheat significantly reduced by 3.5-5.3 cm (P<0.01) and the fresh weight per pant corresponding decreased at the growth stage although without significance. Compared to nongrazed winter wheat, the height of winter grazed wheat was 76.5 cm which significantly reduced by 5.6 cm (P<0.05),spikes of winter grazed wheat reduced 24.3 spikesm-2 and seed yield of winter wheat grazed only reduced 2.5% which did not affect the winter wheat production. In conclusion, the utilization of winter wheat by sheep grazing in wintering was reasonable and practicable in the Loess Plateau agricultural region
Influence of ear stripping and stalk harvesting time on main nutrient components of sweet corn stalks
Gui-long YAN, Shu-fei TIAN, Xiu-ming MU, Chun-mei CAO, Rui-bing WANG, Zhe-kai CHEN
2015, 9(8): 1323-. doi: 10.11829/j.issn.1001-0629.2014-0558
[Abstract](1160) [PDF 455KB](395)
In the present study, the influence of ear stripping and stalk harvesting time on main nutrient components of sweet corn stalks were investigate using the 2 Zea mays cultivarsSBS903 and Krispy King. SBS903 sweet corn stalks harvesting from the day of ear stripping to the seventh day after ear stripping, the contents of neutral detergent fiber (NDF), acid detergent fiber(ADF), acid detergent lignin(ADL), crude protein, crude fat, calcium, and phosphorus decreased whereas the contents of water soluble carbohydrates (WSC) and total sugars increased. The contents of NDF, ADF, ADL, crude ash, crude fat, and calcium in SBS903 sweet corn stalks increased with the postpone of harvest whereas the contents of crude protein, phosphorus, WSC, and total sugars decreased. The Krispy King sweet corn stalks had similar nutrition content variations with the above SBS903. These results suggested that the nutritive value of sweet corn stalks increased with the postpone of harvest time after ear stripping, and the nutritive value of sweet corn stalks decreased with the postponement of ear stripping or stalk harvesting when physiological conditions were similar.
Effects of alfalfa silage on production perfermance, urea nitrogen and blood biochemical index in dairy cow
Gai-ying LI, Hong-xia LIAN, Yu SUN, Tong FU, Teng-yun GAO
2015, 9(8): 1329-. doi: 10.11829/j.issn.1001-0629.2015-0091
[Abstract](1246) [PDF 535KB](406)
In order to study the effect of alfalfa silage instead of the same amount of alfalfa hay on production perfermance, urea nitrogen and blood biochemical index of dairy cows, the big pit silage experiment adding 5% molasses to alfalfa and feeding test were carried out. The results showed that the replacement of alfalfa hay with alfalfa silage were beneficial to improve DMI (Dry Matter Intake), milk yield and milk fat although milk protein decreased in the later stage without significance(P0.05). The contents of MUN(Milk Urea Nitrogen)and UUN(Urinary Urea Nitrogen) decreased for the both groups while the content of BUN(Plasma Urea Nitrogen) firstly decreased and increased. The contents of MUN and BUN from tested groups (maize silage + alfalfa silage) were lower than those from control (maize silage + alfalfa silage hay) without significance whereas the content of UUN performed reversely. In the later stage, the content of UUN from experiment group and control group were 48.35 and 27.52 mmolL-1, respectively, which had significant difference (P0.05). The contents of ALT(Alanine Aminotransferase)、AST(Aspartate Transaminase) and ALP(Alkaline Phosphatase) from tested groups were higher than those from control without significance. The contents of ALB (Albumin) and GLU (Glucose) from tested groups gradually decreased which were lower than those from control without significance. The content of CHO (Chinese Hamster Ovary) from tested group gradually increased and that from control group gradually decreased which reached the biggest difference at 3.64 and 2.82 mmolL-1 (P=0.059), respectively. In conclusion, alfalfa silage feeding was beneficial to improve production perfermance and metabolism ability because the effect of metabolism and utilization of alfalfa silage was reduced in later experiment by Maillard Reaction,
The successful experience of alfalfa industry in United States as a reference to Gansu alfalfa industries
Jie-bing ZHANG, Zhi-biao NAN, Zeng TANG
2015, 9(8): 1337-. doi: 10.11829/j.issn.1001-0629.2014-0362
[Abstract](1022) [PDF 528KB](449)
The United States is the largest country of alfalfa acreage and export around the world. Both its production and trade are much better than China which can provide reference for Chinese production. Gansu Province is the largest province of alfalfa acreage in China. Alfalfa industry is developing rapidly in recent years, however, there are still many problems as the short development period. The present paper reviewed the status of alfalfa production and trade in the United States, analyzed their successful experiences. Taking their experience as a reference, some suggestions and countermeasures were put forward to promote the healthy development of Gansu alfalfa industry after a comprehensive analysis of problems existing in Gansu alfalfa industry.
The feeding quality dynamics of rice straw during natural wilting and the selection of suitable ensilaging time
Neng-xiang XU, Hong-ru GU, Chen-fei DONG, Yun-hui CHENG, Wen-jie ZHANG, Cheng-long DING
2015, 9(8): 1344-. doi: 10.11829/j.issn.1001-0629.2014-0476
[Abstract](1225) [PDF 523KB](289)
In the present study, one japonica rice (Octavia sativa) variety, Wuxiangjing 14, was used to investigate the dynamics of the feeding quality, the silage fermentation quality and microorganisms of straw during natural wilting period, so as to determine the suitable time for rice straw ensilaging and provide instructions for the straw forage utilization. The results indicated that the feeding quality related traits of fresh rice straw showed a declined trend during the natural wilting 72 h which slowly decreased in the first 9 h and the decrease ratio accelerated after wilting 24 h. The nonstructural carbohydrates content (NSC) in rice straw decreased from 16.65% to 13.54%. With the extended of wilting period, the starch content in the rice straw continuously decreased from 6.80% to 3.32% and water soluble carbohydrates (WSC) decreased in the first 3 wilting hours, then increased from wilting 3 h to 24 h, and then decreased slowly afterwards. The fermentation quality of rice straw during natural wilting 72 h significantly changed. In vitro dry matter digestibility(IVDMD)decreased continuously, from 44.56% of wilting 0 h to 37.55% after wilting 24 h, then decreased to 34.90% after wilting 72 h. The lactic acid (LA) content of silage decreased from 44.87 to 24.45 mgg-1 in the first 9 wilting hours, decreased to 12.41 mgg-1 after wilting 24 h, 8.74 mgg-1 after wilting 48 h and 4.50 mgg-1 after 72 h. The NH3N/total N (AN/TN) content of wilting 0 hour was 44.63 mgg-1, and then dropped to 21.39 mgg-1 after wilting 3 hour which followed by increasing between wilting 6 h and 9 h and continuously decreasing afterwards. The pH value increased during the whole wilting period. These results suggested that the fermentation quality of rice straw was the best after natural wilting 3 h which was the best ensilaging time and rice straw had good silage quality in the first 24 h.
Influence of climate warming on change characteristic of husbandry production critical period in Northeastern Qinghai during 1961-2013
2015, 9(8): 1352-. doi: 10.11829/j.issn.1001-0629.2014-0483
[Abstract](887) [PDF 1762KB](379)
Based on daily temperature data collected from 9 meteorological stations in Southern Qinghai Pastoral areas from 1961 to 2013, the spatial and temporal distribution characteristics of animal husbandry critical period, such as growing season, green grass duration, fatten duration and fat-loss duration of livestock were analysis and the change trend of the future animal husbandry production critical period from 2015 to 2035 in RCPs(Representative Concentration Pathways) scene were forecast using the methods of linear regression, morlet analysis and MannKendall test. During these studied 53 years from 1961-2013, the growing season, green grass duration and fatten duration extended with earlier start and later end which lead to significantly longer duration days with extend rate of 2.5, 4.8, 4.6 d10a-1, respectively. However, fatloss duration reversely shorten with the shorten rate of 4.0 d 10a-1. These four indices all had abrupt climate change which happened at 1997/1998. Green grass duration had 8~12 a and 16~18 a cycle and fatten duration and fat-loss duration fluctuated in 4~6 a, 8~12 a, 16~18 a. Under RCPs scene, it predicted that the growing season, green grass duration and fatten duration averagely extended the 11.5~21.5 d and fat-loss duration shorten 15.7~18.1 d in the next 20 years which will be very beneficial to the livestock production in Southern Qinghai Pastoral areas.
Analysis of land usage variations and driving forces in the area around Xanadu Relics
Guan-zhi LIU, Jiang-hong ZHEN, Guo-hou LIU, Hong-ying LI, Zhe-rong LIU, Xijiri
2015, 9(8): 1363-. doi: 10.11829/j.issn.1001-0629.2015-0156
[Abstract](1018) [PDF 1632KB](327)
Combined the land usage status data by remote sensing images from 1990 to 2010 and field investigation, the land usage dynamic changes were analysis and the driving forces were revealed using the single land use dynamic degree, the comprehensive land use dynamic degree, land use degree comprehensive index, land use degree change model in the area around Xanadu relics. The results showed that grassland and cultivated land were key components of land use types, however, sandy land and other types scatter distributed in the area during 1990-2010. Grassland decreased by 6.28% whereas cultivated land and sandy land increased by 1.92% and 3.33%. Land use change very fast with significant volatility. The comprehensive dynamic degree of land use were 0.92% and 0.42% in 1990-2000 and in 2000-2010, respectively. Sandy land change was most significant with 3.23% dynamic degree. Land use degree also increased which transformed from agriculture and husbandry to nonagriculture and nonhusbandry. All the factors including warming and drying climate, sandy land expended to the north, conversion of cropland to forest and grassland, urbanization construction, agriculture, husbandry, industry and tourism development, indiscriminated cutting, overgrazing drove the change of land use. Coordination between land resources and social and economic development were essential for ecological protection and construction which was necessary to protect Xanadu relics, and the basic requirements of grassland cultural heritage.
Field practice model of undergraduate for pratacultural scienceA case of Gansu Agricultural University
Wen-xia CAO, De-gang ZHANG, Xiao-peng PU, Chang-lin XU, Tuo YAO, Gui-xin HU, Zhuo-shan CAI, Ya-juan LI
2015, 9(8): 1372-. doi: 10.11829/j.issn.1001-0629.2015-0216
[Abstract](690) [PDF 882KB](447)
The present paper reviewed the integrated field teaching practice model of undergraduate for Pratacultural Science in Gansu Agricultural University base on stable field teaching practice station. The descriptions included from the aims identification of field teaching practice, relevance analysis and system design of courses, screen of integrated practice program and managements of practice process. The effective integration of practice teaching course, practice program and other multiple teaching resources were achieved by implementing the integrated field teaching practice and the efficiency of field teaching practice were improved by taking the comprehensive, systemic and researchbased practice program as the main body which significantly improved the practical ability and the comprehensive quality of students.