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2012 Vol.29(5)

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Analysis of NDVI distribution and limiting factors of alpine grassland in permafrost area of the upper Shule River
2012, 6(5): 671-675.
[Abstract](1286) [PDF 667KB](532)
The most direct impacts of global warming on permafrost are ground temperature rising and active layer thickening, which will reduce moisture content of surface soil, and then, influence vegetation of permafrost zone. In this study, we studied distribution and changes of NDVI of the alpine grassland and built relationships between NDVI and land surface temperature (LST) to infer the limiting factors (water and energy) of vegetation growth on the source region of Shule River basin, a semiarid zone, which locates in the western of Qilian Mountain. The result showed that the distribution of NDVI was in the shape of reversed U from extreme stable permafrost zone to seasonal frost zone. Second, Since 1995, NDVI has increased slightly in extreme stable and stable permafrost zones and the increase were more significant in substable and transition permafrost zones. However, NDVI has decreased in unstable permafrost zone and seasonal frost zone. Moreover, limiting factor of vegetation growth was transfered from energy in extreme stable permafrost zone to water in seasonal frost zone.
Effect of Shallow tillage during different season on grassland vegetation and
2012, 6(5): 676-680.
[Abstract](1029) [PDF 482KB](613)
An experiment was conducted to investigate the effect of spring and summer shallow tillage on grassland vegetation and soil in the Xilamuren region of North Yin Mountains to find the optimal technology for restoration of degraded grassland. This study showed the spring shallow tillage resulted in severe wind erosion and soil roughness and the summer shallow tillage did not cause wind erosion and soil roughness. The vegetation treated by the spring shallow tillage was sparse because many seedlings and rootstalk were dead or blew by wind, where annual herbs, such as Salsols collina, Corispermum declinatum, Chenopodum aristatum, Artimisia annua became dominant with cover of 30%; however, the vegetation cover treated by the summer shallow tillage was 62% because the Leymus chinensis grew rapidly after several rain and its important value was 0.7. At the end of growth season, the litters cover of grassland treated by the spring shallow tillage was below 10%, and the soil organic matter decreased by 33%; while the litters cover of grassland treated by the summer shallow tillage was 30%, and the soil organic matter increased by 8%. In spring of 2011, the recoverygreen of the spring shallow tillage was worse than that of the summer shallow tillage. This study suggested that the summer shallow tillage was better than spring shallow tillage.
Response of Alternanthera philoxeroides to heavy metals and its sorption effectiveness for heavy metals
2012, 6(5): 681-686.
[Abstract](1165) [PDF 474KB](611)
The phytoremediation is an effective way to solve more and more heavy metal problems and becomes an important field in ecological and environmental sciences, in which the response of plant to heavy metals and its sorption effectiveness for heavy metals are the scientific basis. A pot experiment with different ratio of sludge to soil (0, 5%, 10%, 20% sludge) was carried out to determine the response of Alternanthera philoxeroides to heavy metals and its sorption effectiveness by measuring the chlorophyll content, peroxidase (POD) activity, and superoxidedismutase (SOD) in the leaves of A. philoxeroides after three, four, five and six months treatment, and the metals content (Cd,Cr,Mn,Ni,Pb,Cu, and Zn) in the leaves, roots, and stems of A. philoxeroides after six months treatment. This study showed that the chlorophyll content, POD and SOD activity in the leaves of A. philoxeroide increased as the sludge volume increased; however, they decreased when A. philoxeroide grew in the soil containing heavy metals for six months. This study also showed that the Mn, Ni, Cr, Pb, Cu, and Zn content of the leaves and the stems were higher than those of the roots in different treatments. These results indicated that although A. philoxeroides was useful for phytoremediation of heavy metals in sludge due to its good growth ability, strong tolerance to the heavy metals, and higher transfer coefficient for Mn, Ni, Cr, Pb, Cu, and Zn.
Physiological characteristics of Phalaris arundinacea cv.Picta under rought stress simulated by PEG
2012, 6(5): 687-693.
[Abstract](1299) [PDF 578KB](549)
In order to provide the academic basis of application and popularization, morphological and physiological characteristics of Phalaris arundinacea cv. Picta under drought stress simulated by PEG6000 with different concentrations and different periods were studied in this experiment. The results showed that the percentage of withered leaves, leaf relative electrolytic leakage, contents of MDA and free proline increased gradually; while content of water soluble protein declined firstly and then increased. SOD and POD activities welevated at begainning then declined. Above 7 parameters showed a significant positive correlation with PEG stress. However, the leaf relative water content decreased continuously and showed an obvious negative correlation with PEG stress. According to the morphological and physiological parameters under drought stress, P.arundinacea cv. Picta could be determined as a drought tolerance species and grew normally under moderate drought stress, but it would be damaged under severe drought stress.
Evaluation of salt tolerance of four Festuca arundinacea varieties during seed germination stage
2012, 6(5): 694-698.
[Abstract](1305) [PDF 390KB](641)
Seeds of four Festuca arundinacea varieties (Barlexas, Arid 3, Jaguar 3 And Red Elephant) germinated under the stress of 0, 0.2%, 0.4%, 0.6%, 0.8%, 1.0% NaCl solutions. The relative germination percentage, the relative germination potential, the ratio of root to seedling and relative reduction percentage of root length were measured during the germination stage. The results of this study showed that the relative germination percentage, relative germination potential and the ratio of root to seedling of four varieties declined with rising salt concentrations, while the relative reduction percentage of root length increased. The results of comprehensive evaluation showed that Barlexas was the most salttolerant variety, but Arid 3 was the weakest one among four varieties.
Effects of light intensity on morphological change and lawn quality of wild Cynodon dactylon
2012, 6(5): 699-703.
[Abstract](1213) [PDF 380KB](620)
In order to provide reasons for developing and using wild Cynodon dactylon germplasm resources, the morphological changes of aerial parts of 4 germplasms of wild C.dactylon under diffirent light intensities were compared with Tifway 419 (an introduced variety of C.dactylon) in this study. The effects of light intensities on their lawn qualities were also evaluated. The results showed that when the illumination was reduced from 100% to 68.0% and 38.5%, the erect stem height, the stem internode length and the leaf length increased and the leaf size enlarged. There were negative correlations between light intensities and above modalities. The stem diameter and the leaf width decreased, which had positive correlations with light intensities. The lawn qualities of wild C.dactylon were downgraded due to the morphological changes of the stems and leaves. The changes on the stems and leaves of C.dactylon G1 and G4 were the minimum so that their lawn qualities were higher with strong shadetolerance. However, the stems and leaves of C.dactylon G3 were changed much under different light intensities, so its lawn quality was the worst among the four germplasms.
Preliminary evaluation of salt tolerance of Axonopus compressus
2012, 6(5): 704-709.
[Abstract](1426) [PDF 479KB](721)
A preliminary assessment of Axonopus compressus salt tolerance among one cultivar and 19 different geographical distributions of accessions utilized total stem length, total number of branches, root to shoot ratio, leaf brown percentage and turf quality. The results showed that there were significant or very significant differences among different accessions treated with 150 mmolL-1 of NaCl solution. The coefficients of variation of different indicators ranged from 9.1%-50.9%, of which the minimum of root to shoot ratio, and maximum of leaf brown percentage. There were significant correlations (maximal correlation coefficient of -0.927) among different indexes of A.compressus. Based on the five characteristics (total stem length, total number of branches, root to shoot ratio, leaf brown percentage and turf quality), SPSS 16.0 was used to divide A.compressus accessions into three salt tolerance types:salt tolerance, intermediate and saltsensitive.
Resource survey of wild Carex plants and evaluation of their ornamental characteristics in Beijing
2012, 6(5): 710-716.
[Abstract](966) [PDF 397KB](547)
Nature resources of Carex plants and their ornamental characteristics in Beijing was investigated in this study. The results showed that 18 species of wild Carex were found from 7 surveys. 6 out of 18 species could be utilized as turfgrasses, which were C.breviculmis, C.giraldiana, C.stenophylloides, C.humilis, C.subpediformis and C.lanceolata. Some of other species, such as C.leiorhyncha, C.remotiuscula, C.longerostrata and C.neurocarpa could be used as ornamental grasses with other plants configuration application in Landscape.
Research progress on carbon sinks and carbon sources in the turfgrass ecosystem
2012, 6(5): 717-723.
[Abstract](1020) [PDF 453KB](638)
The research progress of carbon sinks and carbon sources in the turfgrass ecosystem both at home and abroad was reviewed in this paper. In the first part, the paper reviewed three aspects: 1) turfgrass biomass, leaf area index and net primary productivity; 2) dynamic changes of soil organic carbon accumulation in the turfgrass ecosystem; 3) soil respiratory intensity. In the second part, it discussed the main research methods of carbon sinks and carbon sources in the ecosystem. There are two main methods, which are eddy correlation and chamber measurements. Furthermore, in the third part, we summarized different factors affected the dynamics of carbon sinks and carbon sources. The factors could be summed as two aspects, which on the one hand was natural environmental factors, such as photosynthetic active radiation, atmospheric temperature, soil moisture content and soil temperature; on the other hand was human factors, including mowing, fertilization and irrigation,etc. In the last part of the paper, it also indicated problems of the present researches and the sides to be improved. This paper thus provides reference information for relevant researches in the future.
A review on methods of sterilization and inhibition of arbuscular mycorrhizal fungi in Soil
2012, 6(5): 724-732.
[Abstract](1303) [PDF 460KB](1117)
A symbiotic relationship between arbuscular mycorrhizal fungi (AMF) and plant roots is one of the hottest studies in the microbial research field currently. Establishing a nonAMF control group (nonAMF soil) is a key point to reveal effects of arbuscular mycorrhizal fungi on plants. This paper summarizes 5 methods, including autoclaving, chemical fumigation, irridation, benomyl and severance of hyphae, to establish nonarbuscular mycorrhizal fungi control groups. Autoclaving, chemical fumigation and irridiation can be adopted in indoor experiments, while the former two may affect the phsical and chemical charasteristics of soil and the latter is not enviromentalfriendly. Benomyl and severance of hyphae are suitable for outdoor experiments. The quantity of benomyl should be rigidly controlled due to its negative effects on the environment. Though severance of hyphae would not damage the environment, it may affect the exchange of water and nutrition between plants and soil. Thus, researchers should choose suitable methods for their studies auording to enviroment and purpose of the study.
2012, 6(5): 733-734.
[Abstract](850) [PDF 397KB](1290)
Tissue culture and rapid propagation of Orostachys malacophyllus leaves with axillary buds
2012, 6(5): 735-740.
[Abstract](1343) [PDF 608KB](584)
The leaves with axillary buds of Orostachys malacophyllus were selected to investigate the effect of different plant growth regulators on axillary buds initiation by using MS medium with different concentrations of 6benzylamino purine, 1naphthaleneacetic acid, and 2,4dichlorophenoxyacetic acid for developping an efficient procedure of plant regeneration of O. malacophyllus. The results of this study showed that the optimum initiating culture medium for leaves axillary buds of O. malacophyllus was MS medium appended with 3 mgL-1 6benzylamino purine and 0.1 mgL-1 1naphthaleneacetic acid. The optimum proliferative medium for axillary buds of O. malacophyllus was MS medium added with 1.5 mgL-1 6benzylamino purine and 0.02 mgL-1 2,4dichlorophenoxyacetic acid, and multiplication times was 5.35. In root induction culture, shoot clusters in the1/2 MS medium supplemented with 0.3 mgL-1 1naphthaleneacetic acid were well rooted and grew vigorously with the 96.67% rate of root formation, and the best survival rate was 76.67%. This study suggested that the efficient plant regeneration in O. malacophyllus from leaves with axillary buds was possible.
Establishment and optimization of SSRPCR system of Salix oritrepha
2012, 6(5): 741-747.
[Abstract](1028) [PDF 585KB](473)
In this study, the SSRPCR system of Salix oritrepha from four altitudes was optimized. The main factors of the system were studied using orthogonal design and single factor experiment. Meanwhile, the suitable annealing temperature of primer SHUK123 was optimized. The results of this study showed the optimized system was: 1 L Mg2+ (2.50 mmolL-1), 1.5 L dNTPs concentration (0.10 mmolL-1), 1 L Taq polymerase (0.5 U), 1 L DNA template (20 ngL-1), 2 L each primer concentration (0.5 molL-1), 2 L 10 Taq Buffer in a mixture of 20 L. The PCR procedure included an initial step of 94 ℃ for 3 min, followed by 30 cycles of 94 ℃ for 45 s, annealing 45 s (annealing temperature varies with the primers), 72 ℃ extension 30 s, and a final extension at 72 ℃ for 5 min. The products of PCR were saved at 4 ℃. The optimized annealing temperature of primer SHUK123 was 56 ℃. The optimized SSRPCR system was stable and repeatable, which will be a good choice in the study of S. oritrepha.
Effect of H2O2 pretreatment on salt tolerance of wheat seedlings
2012, 6(5): 748-752.
[Abstract](1149) [PDF 468KB](433)
The improvement of salt tolerance is of great importance to enhance wheat (Triticum aestivum) adaptability to saline and alkalized soils in the practice of wheat cultivation. Under NaCl and H2O2 treatments, the plant height of wheat and related physiological parameters were measured to elucidate the effect of H2O2 pretreatment on salt tolerance of wheat seedlings. Leaf malondialdehyde (MDA) content, relative electrical conductivity (REC), water soluble sugar (WSS) content, proline content and peroxidase (POD) activity increased with 1.2% NaCl treatment. However, under H2O2 + 1.2% NaCl treatment, there was less increment in MDA and REC contents, more increment in WSS content and POD activity, and less decrease in plant height of wheat seedlings compared to those under 1.2% NaCl treatment. It suggested that H2O2 pretreatment could, to some extent, improve salt tolerance of wheat seedlings, but there was difference in the response to such treatments between two wheat cultivars.
Influences of CoCl2 on seed germination and seedling resistance of Lolium multifolorum under acid stress
2012, 6(5): 753-758.
[Abstract](1188) [PDF 464KB](628)
Seeds of Lolium multiflorum were soaked in different concentrations of CoCl2 solutions for 24 h and then germinated in acid solutions with different pH to study effects of CoCl2 on seed germination and seedling growth under acid stress. With increase of acidity the germination vigor, germination capacity, germination index, vitality index and chlorophyll content of L.multiflorum deceased obviously, while the inhibition index of root, malondialdehyde (MDA) content, production rate of O-2 and H2O2 content and the activities of superoxide dismutase (SOD) increased significantly. The activities peroxydase (POD) increased firstly and then decreased; and membrane stability index also declined. Under the condition of acid stress, seed germination rate, chlorophyll content, shoot length, dry weight of aerial part and the SOD activity of L.multiflorum were obviously elevated by the treatment of 0.1 mmolL-1 CoCl2, while the MDA content and POD activity were impaired. In general, under the acid stress, the seed germination, seedling growth and the resistance to acid stress of L.multiflorum were prompted obviously by the treatment of 0.1 mmolL-1 CoCl2 .
Effects of temperature on the germination of Elymus nutans seeds
2012, 6(5): 759-767.
[Abstract](1138) [PDF 714KB](488)
This study was aimed at determing suitable germination conditions for Elymus nutans seeds collected from four altitudes (3 941, 3 528, 3 212 and 2 925 m). These seeds were germinated under different temperatures and light gradients. The results indicated that the suitable germination temperatures of E.nutans ranged from 15 ℃ to 25 ℃. Variable temperature can significantly improve germination uniformity and germination rate. The best combination of variable temperature was 20 ℃/10 ℃, in which germination rate and germination potential increased 20.2% compared with that at 20 ℃. Germination of E.nutans seeds were not sensitive to light conditions. In the lower temperature, seed germination ability from the lower altitude was superior to that from the higher altitude, while in the higher temperature, seed germination ability from the higher altitude was superior to that from the lower altitude. In the intermediate temperature, however, the seed germination performance did not show significant differences among four altitude levels.
Comparison of morphological and productive characteristics between MT1 elephant grass and Mott elephant grass
2012, 6(5): 768-774.
[Abstract](1278) [PDF 442KB](500)
Mott elephant grass (Pennisetum purpureum cv. Mott) is a kind of valuable forage in south China. In order to evaluate productivity of MT1 elephant grass (P. purpureum cv. MT1), bred from Mott population, comparative analysis between MT1 elephant grass and Mott elephant grass on morphological characters, modular and bunch biomass during vegetative and reproductive growth periods were conducted from 2007 to 2009. The results indicated that the plant height and clump diameter of MT1 were significantly higher than those of Mott (P<0.01), and the tiller number of Mott was a little more than that of MT1. The leaf biomass (in vegetative period), dead leaf biomass, culm biomass, inflorescence biomass and ramet biomass of MT1 were significantly higher than those of Mott (P<0.01). However, the leaf to culm ratio of Mott was significantly higher than that of MT1 (P<0.01). The bunch biomass of MT1 in vegetative and reproductive growth periods, were 1.42-1.84 times and 1.07-1.87 times of Mott, respectively. The annual biomass of MT1 ranged from 31 246.50 to 48 838.60 kgha-1, while that of Mott just ranged from 18 201.70 to 36 306.60 kgha-1. In summary, the productivity of MT1 was better than that of Mott according to the outstanding biomass yield.
Evaluation of yield and nutrition performence of four Bromus inermis germplasms in alpine region
2012, 6(5): 775-779.
[Abstract](1280) [PDF 398KB](465)
Four Bromus inermis germplasms were compared in agronomic characters, grass yield, seed yield and nutrients at dry farming in the western town of Haibei of QinghaiTibet Plateau. The results of this study showed they could over winter safely in this region, and performed strong capacity of drought, coldresistance.Grass yield, hay yield and seed production of B.inermis cv. Gannongda were the highest among four materials with 30 136.11, 14 833.61 and 2 116.20 kgha-1. The difference between this material and the other three materials was significantly (P0.05), which indicates B.inermis cv. Gannongda is a forage cultivar with high yield and good quality.
Effects of different nitrogen and phosphorous fertilizer on yields and nutrients of Vicia unijuga
2012, 6(5): 780-784.
[Abstract](944) [PDF 639KB](443)
The experiment was performed to investigate the influences of nitrogen (0, 50, 75, 100 kgha-1) and phosphorous (0, 70, 140, 210 kgha-1) fertilizer on nutrients and yields of Vicia unijuga. It was found that both 75 kgha-1 nitrogen fertilizer and 140 kgha-1 phosphorous fertilizer could maximize the dry matter yields of V.unijuga, the highest yield was 3 048 and 2 752 kgha-1, respectively. The yields were 50% and 35% higher than those with no fertilizer, respectively. In addition, by using 75 kgha-1 nitrogen fertilizer and 140 kgha-1 phosphorous fertilizer, the contents of Cu, Mn and Zn elements were much higher than those without fertilizer (P0.05). Under the 50 kgha-1 nitrogen fertilizer and 70 kgha-1 phosphorous fertilizer, the contents of water soluble sugar and crude protein were all the highest. The contents of water soluble sugar and crude protein in 50 nitrogen were 11.0% and 23.5% higher than those without nitrogen. It should be noted that excessive amounts of nitrogen or phosphorous fertilizer would decrease the yield and quality of V.unijuga, and the actual amount of fertilizer should be considered in practice.
Maize yield and growth on waste substrate in organic ecotype soil free cultivation
2012, 6(5): 785-789.
[Abstract](9367) [PDF 372KB](6485)
The effect of waste matrix produced from organic ecotype soilless cultivation then returned to soil on botanical characteristics, yield and economic benefit of maize (Zea mays) seed production and the soil properties of available potassium, phosphorus and alkalihydrolyzable N were studied using a randomized block experiment in this paper. The result showed that the maize seed yield of T1 (4 m3 waste matrix +N24P12K6) was the highest; yields between T3 (4 m3 waste matrix +N6P3K1.5 ) and Control (N24P12K6) did not show a significant difference. Spike grain weight, 100seed weight and yield of T1increased by 7.3 g, 2.03 g, 2.07 kg compared to Control, respectively. Soil organic matter, available potassium, available phosphorus and alkalihydrolyzable N in T1 increased by 0.4 gkg-1, 24.61 mgkg-1, 0.68 mgkg-1, 0.65 mgkg-1 compared to Control, respectively. The income of T3 increased by 1 791.6 CNYha-1 and the chemical fertilizer investment reduced by 2 207.8 CNYha-1 compared with Control by the organic ecotype waste matrix. However, soil chemistry properties and maize botanical characteristics did not show significant differences between treatments.
Evaluation of production performance of 35 introduced varieties of alfalfa in Chifeng area of Inner Mongolia
2012, 6(5): 790-797.
[Abstract](1345) [PDF 500KB](625)
A field experiment of 35 introduced varieties of alfalfa (Medicago sativa) was performed in Chifeng area to compare the differences in winter surviving rate, plant height, fresh yield, hay yield, leaf to stem ratio in the second growth year; and the productive adaptability of 35 varieties were also evaluated with gray correlation analysis. The results indicated that Longmu No.806 was the best on its comprehensive characteristics, while Grandeur, Zhaodong, Longmu No.801 and Gongnong No.1 were in the seond best group. These cultivars deserve popularization in Chifeng area. Zhaodong, Longmu, Gongnong No.1 and Aohan Alfalfa with higher winter surviving rates and excellent comprehensive characteristics were more suitable to be extended in the colder climate of northern counties of Chifeng area.
The age structure of Bromus inermis populations in two habitats in Yili of Xinjiang
2012, 6(5): 798-803.
[Abstract](1075) [PDF 453KB](409)
In order to evaluate the reproduction potential of natural populations of Bromus inermis in Yili of Xinjiang, the age structure of tillers, rhizomes, winterness tillers and buds of B. inermis sampled from the fields by an unit area sampling method in two habitats (meadow or arid habitat) were analyzed in August 2010. The results showed that in two habitats, the dominance level of tillers, rhizomes, winterness tillers and buds of B. inermis populations at the lowest two age classes was significantly higher than those in other age classes. Reproductive tillers had three age classes, while vegetative tillers, rhizomes, winterness tillers and buds all had four age classes. The tiller nodes of rhizome could reproduce a maximum of four generations and survive for up to five growing seasons. The number of tillers and buds, and the length of rhizomes of populations in the meadow habitat were larger than those in the arid habitat; while the number of winterness tillers was opposite. The ranking of the number of vegetative tillers and winterness tillers were 1yearold>2yearsold>3yearold>4yearold, the number of buds was 0yearold>1yearold>2yearold>3yearold. The components of tillers, rhizomes, winterness tillers and buds of B. inermis natural populations showed expansive age structures in toth habitats.
Change of spatial pattern of Potentilla fruticosa population along altitudinal gradient in Dongdahe forest area of Qilian Mountains Nature Reserve
2012, 6(5): 804-808.
[Abstract](1076) [PDF 399KB](461)
The basic characteristics, coverage spatial pattern and the change along altitudinal gradient of Potentilla fruticosa population in Dongdahe forest areas of Qilian Mountains Nature Reserve were studied by using the methods of pattern indexes, accumulation intensity indexes and accumulation mean values. The results showed that the average population abundance, the average coverage and average height of Potentilla fruticosa reached their maximum values at an altitude of 2 842, 2 990 and 3 017 m, respectively. The appropriate altitude of P. fruticosa population distribution were about 2 900 ―3 100 m in the southeast slope.The population coverage was an aggregated distribution. With altitude elevating, the pattern index increased gradually and reached the maximum value at 2 990 m, and then fluctuated and declined. The change of accumulation intensity had the same pattern as the pattern index. The main reason for the aggregated distribution of P. fruticosa population was the survival environment of P. fruticosa population.
A study on biomass potentials of perennial gramineous energy plants
2012, 6(5): 809-813.
[Abstract](1059) [PDF 448KB](494)
Takeing Panicum virgatum. as a control, the morphological properties and biomass characteristics of Miscanthus sacchariflora, Miscanthus sinensis, Arundo donax, Phragmites australis, Miscanthus sinensis Zebrinus, Glyceria maxima were studied in Nanjing. The results showed that annual dry matter yield (32.11 and 29.96 tha-1), calorific value (17.692 and 18.202 MJkg-1) and standard coal equivalent (19.42 and 18.64 tha-1) of M.sinensis and M.sacchariflorawere were higher compared with other materials, while their ash contents (29.7 and 23.8 gkg-1) were lower. The measured indicators of all materials, except calorific value, moisture and hemicellulose, were significantly different with those of P.virgatum (switchgrass). Thus, native Miscanthus plants compared to switchgrass were excellent biomass energy plants for China. The calorific values of bioenergy plants were negatively correlated with ash contents. Biomass yield, ash content and caloric value are two effective targets for screening the appropriate biomass linear regression relation energy plants.
Effects of grazing on the vegetation composition of Lolium perenne and Trifolium repens mixed pasture
2012, 6(5): 814-820.
[Abstract](1679) [PDF 435KB](495)
In order to understand effects of grazing intensities on vegetation composition of Lolium perenne and Trifolium repens mixed pasture, the chemical characteristics of soil, L. perenne tillers, T. repens stolons, the number of leaves, the stem and leaf composition, the height and biomass of herbage under four grazing intensities (light, moderate, heavy and over grazing; with postgrazing height at 7.5 cm, 5.5 cm, 3.5 cm and2.0 cm, respectively) were studied at Weining, Guizhou. The results showed that the response of soil available nutrient contents to the grazing intensity was more sensitive, but their stability was lower. Tiller density and leaf biomass of L. perenne increased significantly with increasing grazing intensity, while tiller weight of L. perenne and stolon density of T. repens, height and biomass of herbages decreased significantly. Grazing intensities had no effects on the number of leaves of L. perenne and T. repens, the ratio of stem to leaf and stolon weight of T. repens. The homogeneity of growth characteristics of L. perenne and T. repens was reduced and their plasticity was enhanced by the grazing treatments. The response of L. perenne to grazing intensity was more sensitive than that did T. repens, whereas the plastical growth of the former was lower than the latter. Dactylis glomerata and native species had higher coefficients of variation under different grazing intensities. Thus, the effect of grazing animals on grassland vegetation could be revealed from three levels: individual plants, populations and communities. The low component sown grass (D. glomerata) and native grass species were the key species during the change of vegetation composition of mixed pasture.
Inoculation effects of phosphoric bacteria agent on alfalfa
2012, 6(5): 821-823.
[Abstract](1023) [PDF 339KB](433)
Inoculated effects of phosphoric bacteria agents on potted alfalfa (Medicago sativa) after 77 d indoor incubation have been evaluated in this study. The results indicated that inoculating the phosphoric bacteria agent could improve alfalfa growth significantly. Compared with control (without the phosphoric bacteria agent), numbers of root nodule and yield of alfalfa increased 32.4% and 45.95%; and contents of WSC, CP and NDF were improved 0.40%, 2.24% and 4.88%, respectively. Compared with a calcium superphosphate treatment, contents of WSC, CP and NDF of potted alfalfa inoculated with the phosphoric bacteria agent were also improved 0.03%, 0.02% and 0.32%, respectively. The suitable dosage of the phosphoric bacteria agent was 22.5 kgha-1 and increased the production by 12.9% compared with application of 750 kgha-1 chemical P and K fertilizer.
Weed species and distribution and harmfulness of vegetables field of eggplant in the Changde Area
2012, 6(5): 824-828.
[Abstract](987) [PDF 413KB](516)
A field survey was conducted to investigate the weed species and their distribution and harmfulness of vegetables field of eggplant in the Changde areas. This study indicated that the weeds of vegetables field of eggplant were 38 species, belonging to 16 families, in which Gramineae, Compositae, Caryophyllaceae, Polygonaceae, Scrophulariaceae, Cyperaceae and Cruciferae were dominant families. The dominant species included Beckmannia syzigachne, Digitaria sanguinalis, Cyperus rotundus, Cerastiwm arvense, Portulaca oleracea, Alternanthera philoxeroides, Acalypha australis, Mazus japonicus, Ludwigia prostrata, Poa annua. This study also comprehensively compared the weed species and their distribution and harmfulness in vegetable field with plastic film to those in vegetable field without plastic film, which would provide the important information for control weeds of vegetable field of eggplants.
Effects of depilation by drugs on serum hormone and enzyme levels of Liaoning Cashmere goat
2012, 6(5): 829-832.
[Abstract](1094) [PDF 373KB](553)
This study was to examine effects of depilation by drugs on blood hormone and enzyme levels of Liaoning Cashmere goat. Twelve fouryearold female Liaoning Cashmere goats were divided into four groups randomly, in which control group was without any treatment, groupⅠ was treated with subcutaneous implantation of melatonin (60 mggoat-1), groupⅡ was subcutaneous implantation of melatonin plus injected muscularly with cyclophosphamide (26 mgkg-1), and groupⅢ was only injected with cyclophosphamide (26 mgkg-1). To determine the levels of several serum hormones and enzymes, blood samples of goats were collected and tested at 0, 30 and 50 d after treatments. Results obtained from the study showed that subcutaneous implantation of melatonin increased the levels of alpha amylase (AAMY) and alkaline phosphatase (ALP), but reduced the levels of adrenocorticotrophic hormone (ACTH), cortisol (Cor), epidermal growth factor (EGF) and creatine phosphokinase (CPK). Injection of the cyclophosphamide increased the levels of creatine phosphokinase, alpha amylase and cortisol, and reduced the levels of alkaline phosphatase and melatonin (MT).
Construction of engineered bacteria for onestep producing alcohol with Jerusalem artichoke
2012, 6(5): 833-836.
[Abstract](1057) [PDF 411KB](470)
To obtain fusant strains being able to produce ethanol directly from Jerusalem artichoke (Helianthus tuberosus) materials efficiently, the protoplast fusion technique was used and some appropriate conditions were chosen for protoplast preparation and fusion. The protoplast fusion was conducted between Saccharomyces cerevisiae and a penicillium strain obtained by selfscreening with a high yield of inulinase. The abilities of inulinase and ethanol production of detected fusants was determined. Their genetic stability was also studied. Finally, a superior strain named R8 was chosen for inulin alcoholic fermentation. The results showed that the ethanol content of fermented products was 41.16% and the raw sugar utilization rate was 75.52%.
Comparison of chlorogenic acid yield in tender leaves of different ramie germplasm
2012, 6(5): 837-840.
[Abstract](1074) [PDF 377KB](489)
Chlorogenic acid yield of different ramie tender leaves were analyed in this study. The result showed that the chlorogenic acid yield differences are more obvious for different varieties of ramie ,Xiangtan Qingpima and Sichuan Hongxian Yuanma all had higher yield were 19.809 kgha-1 and 16.714 kgha-1(the agronomic traits and the average content of chlorogenic acid were more better than other germplasm of ramie), instead that the yield of Changning Qingjiaoma ,Anren Huangjiama ,Suining Qingma,Yuanjiang Qingma,Anren Huangshuimawas low between 2.191-1.268 kgha-1. the factors that affect the chlorogenic acid production was ramie leaves yield(dry weight) and the content of chlorogenic acid in ramie leaves. At the same time ,the agronomic traits also produced a variety of integrated effects for the yield of chlorogenic acid of different germplasm of ramie.
Status, problems and countermeasures of criminal protection about grassland in China
2012, 6(5): 841-844.
[Abstract](991) [PDF 373KB](529)
Grassland protection issues is directly related to the ecological security and sustainable development of socioeconomic in China. The strategic position and seriously damaged situation of grassland show that the grassland urgently needs the criminal law to effectively protectedcriminal protection. The author analyzed summarized the criminal protection of grasslands in China at this stage and pointed out the problems of grassland criminal protection. The effective criminal protection of grassland can not be withourelies ont a complete and mature grassland criminal laws and fully implemented regulations of these lawsto be fully implemented (judicial).
Current situation and restoration strategy of ecological function of water supply area in Maqu County
2012, 6(5): 845-847.
[Abstract](1089) [PDF 364KB](482)
The grazing capacity was excessive in important water supply area of Maqu County. In the area the grassland was degrading, the land was deserting, the function of water conservation was deteriorating and the wetland was shrinking. The management measures for solving the problems mentioned above were diminishing human and animal activities, raising grass and planting trees. After implementing the policies, we may control land desertification, restore grassland vegetation and finally, we may resume the ability of water conservation and ecological function of water supply of the area in Maqu County.