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2013 Vol.30(3)

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Point pattern analysis of subalpine meadows in Dongling Mountain
Chunling XIANG, Jintun ZHANG
2013, 7(3): 317-321.
[Abstract](1304) [PDF 759KB](344)
In this study point pattern analysis and a multivariate spatialpattern analysis method were used to examine the spatial pattern of subalpine meadows in Dongling Mountain. The result showed that population patterns and spatial association of the subalpine meadow populations were closely linked with the tourism interference factors. With strong interference of the tourism, the subalpine meadow populations have shown the characteristic with clustered distribution and spatial negative association at each scale.
Age structure of modules on Calamagrostis pseudophragmits population in Huocheng County
Yu ZHAO, Ying LIU, Nurmamat
2013, 7(3): 322-327.
[Abstract](1955) [PDF 418KB](270)
Calamagrostis pseudophragmits is a perennial, rhizomatic and typical clone grass. Components and age structure of modules of C.pseudophragmites populations were studied at the end of growth season in different habitats in the Gully Mountains in Huocheng County of Xinjiang, China. It was found that the tiller nodes of C.pseudophragmits in three habitats kept alive as long as for 6 year, and there were five age classes of tillers which showed a stable age structure. Viewing the general conclusions as a whole, the productivity of per tillers in the second habitat (H2) was significantly higher than those of the third habitat (H3), the least was 2nd (H1), and there were significant difference among different habitats which showed that some difference of productivity per tiller occurred in different vegetations (P0.05). The cumulate length of rhizomes and its biomass was the highest for the oneyearold class, and it decreased with an increased age, the storage of dry matter within per meter rhizome was the highest for the 1st (in H1) or 2nd (in H2 and H3) age class. The results showed that loosen and damp sandy soil was advantageous to the growth and storage of dry matter in rhizomes.
Relationships between stocking rate and species richness on alpine steppe
Hua WANG, Fujiang HOU, Hang YUAN, Xiuli WAN, Lei XU, Xianjiang CHEN, Shenghua CHANG
2013, 7(3): 328-333.
[Abstract](1799) [PDF 446KB](402)
The research selected six plots of different grazing gradient of winter pasture in Sunan Deer Farm, and used neststyle methods to investigate the number of grassland plant communities species. Focus on the relationship between stocking rate and species richness of grassland community in Gansu wapiti grazing system on mountain grassland. The results showed that:1)Species increased gradually with the expansion of sampling area in winter pasture, among the grazing intensity gradient, the trend of species richness resulted from grazing alleviate increased, and the contribution of grazing effected on species richness enhanced. 2)The minimum sampling area of alpine grassland was 0.71-1.54 m2, and the dramatic change of species richness happened in the range of 0.16-0.32 m2 and 0.32-0.64 m2 respectively in all stocking rates. 3)Species richness showed downward trend along with increasing of stock rate, and inflection point of stocking rates was 2.45 AUMhm-2. The effect of stocking rate on species diversity was different on both sides of inflection point. That suggested 2.45 AUMhm-2 was the appropriate stocking rate on alpine grasslands. 4)The contribution of stocking rate on species richness does not work at the condition of an sampling area of more than 2.56 m2 in the pasture scale.
A screening of the substrates for Sedum lineare in tropic and humid environmental conditions
Cong TANG, Wei GUO, Guifen CAI, Lingying XIAN, Nian LIU
2013, 7(3): 334-340.
[Abstract](1596) [PDF 438KB](311)
Sedum lineare is a popular choice among green roofing projects due to its extensive management, easy propagation and tolerance for heat and drought adaptability. However, the project practice shows that Sedum lineare cannot resist water logging, it even leads to root rot and death in tropic and humid environmental conditions. The test is adopted to screen the substrates of S.lineare for the green roofs with the import peat, domestic peat, green waste, perlite and palm fiber. Based on the growth index of S.lineare and the physicochemical property of the substrates, the test aims to screen which is the most suitable substrate for S.lineare. The result shows that the green waste is the best suitable substrate for S.lineare in tropic and humid conditions, and it is the cheapest one to save engineering cost. Furthermore, an orthogonal experiment is adopted to find green waste∶perlite∶Palm fiber is 8∶1∶3 and 8∶3∶2 and both have a remarkable effect on S.lineare growth.
The toxicities and effects text of seven fungicides on Pythium aphanidermatum
Yinping LI, Qinghua YUAN, Yu WANG
2013, 7(3): 341-345.
[Abstract](1590) [PDF 514KB](424)
The toxicities of seven fungicides were tested by using mycelia growth rate method and inhibiting method of the formation of sporangium. Potted plants test were adopted by using seed treatment to test the control effect of Pythium aphanidermatum. Laboratory toxicity tests results indicated that the effects of these fungicides were significantly different in inhibiting the growth of mycelium and the formation of sporangium of P.aphanidermatum. Cymoxanil mancozeb, Mancozeb and Propamocarb had the better inhibiting effect on the mycelia growth and the EC50 values of these fungicides were 1.28, 1.28, 3.26 mgL-1. While in the inhibiting experiment of the formation of sporangium of P.aphanidermatum, Pyraclostrobin, Cymoxanil mancozeb and Mancozeb performed well with the EC50 value 0.09, 0.21, 0.46 mgL-1. After taking Fungicide seed treatments, all of tall fescue germination rate had different degrees of improvement, and Cymoxanil mancozeb and Mancozeb had the better control effect. Based on the results of the laboratory toxicity tests and pot tests, it's concluded that Cymoxanil mancozeb and Mancozeb on Pythium disease control effect is better than in the other five kinds of fungicides.
Effects of eugenol on soil microbes in wheat fababean intercropping and monocropping systems
Huijuan LIU, Qiang CHAI, Gaobao HUANG, Haiyan ZHOU, Jing ZHU
2013, 7(3): 346-351.
[Abstract](1779) [PDF 401KB](316)
In order to provide theoretical basis for the regulation of intercropping system of existed allelochemicals, effects of eugenol, a kind of wheat rootexudate, on microbial population and diversity of intercropped and monocropped wheat fababean systems under 75% field capacity condition were investigated by a pot experiment. Results showed that as a whole, soil microbial diversities decreased, fungi and actinomycetes population decreased, and bacteria population increased in wheatfaba bean intercropping and monocropping systems. Among the three cropping patterns, compared with no eugenol application, eugenol treatments displayed inhibitory effects on the amounts of soil fungi and actinomycetes, which decreased by 21.95%-98.42% and 13.33%-92.82%, respectively. Bacterial population of sole wheat decreased by -118.63%-90.73% than intercropping treatments, while that of sole bean increased by -56.39%-76.76%. The relative amount of actinomycetes of the microbial population declined by -4.42%-4.32%, while the ratio of bacterial population increased by -4.36%-4.32%. Compared with wheat and bean monoculture, wheatbean intercropping could reduce soil microbial diversity index, in which soil microbial diversity index decreased by 15%-26.98% and -45.45%-6.67%, respectively. The microbial diversity index of monoculture with eugenol treatment declined.
Effects of Achnatherum inebrians/Neotyphodium endophyte symbiont on microflora and nutrient of soil
Xi HUANG, Xiuzhang LI, Qing CHAI, Chunjie LI
2013, 7(3): 352-356.
[Abstract](1555) [PDF 401KB](463)
Drunken horse grass (Achnatherum inebrians), is a kind of intoxicating grass growing on native grassland in Northwestern China. The aim of this research is to determine the effects of endophyte infected (E+) A.inebrians on the quantity of soil microbes and nutrient components of rhizosphere soil of accompanying species. The results indicated that the quantity of soil fungi was 1.33-1.55 times than accompanying species in Sangke, Ganjia and Yuzhong, where soil bacteria was 1.60-2.65 times. The measurement results of soil nutrients showed that organic matter, total nitrogen, available phosphorus and available potassium of rhizosphere soil of A.inebrians were higher than those of accompanying species. However, the content of total phosphorus and total potassium had no significant effects on the rhizosphere soil of A.inebrians and accompanying species.
Isolation of endophytic fungi from medicinal plant Glycyrrhiza uralensis and its microbial inhibition activity
Jiangtao BI, Xiaoxia WANG, Weimin CHEN, Jing WANG, Dahan HE
2013, 7(3): 357-364.
[Abstract](2267) [PDF 494KB](334)
In order to explore the resource diversity and microbial inhibition activities of endophytic fungi from medicinal plant Glycyrrhiza uralensis,the endophytic fungi were isolated from root,stem and leaf of the host by tissue inoculation culture,the five kinds of pathogenic fungi,Gaeumannomyces graminis var. tritici,Colletotrichum gloeosporioides,Botrytis cinerea,Fusarium oxysporium f. sp. cucumeris,Rhizoctonia solani,and the four kinds of bacteria,Bacillus subtilis, Escherichia coli, Staphylococcus aureus,Pseudomonas aeruginosa,were used as indicators to test microbial inhibition activities of the isolates by agar plate antagonistic action and modified agar gel diffusion methods. The results indicated that twenty endophytic fungi strains were isolated from the root,stem and leaf as a whole, and the most isolates came from the root,making up 65.0% of the total, then from stem, and leaf as the least;Based on morphological characters,the isolated strains attribute to two genera,two families and five orders,and Fusidium sp.was the dominant genera, amounting to 85.0% of the total isolates;For the isolated strains fifteen strains had antifungal activities against one or more pathogenic fungi,accounting for 75.0% of the total isolates,nineteen strains showed antibacterial activities to one or more bacterial indicators,taking up 95.0% of the total isolates; There were seven strains showed inhibition activities to B. subtilis, and eight strains had inhibition activities to S. aureus and three strains expressed inhibition activities to E. coli and one strain to P. aeruginosa; Of which the strain RLEFR015 had significant differences statistically for microbial inhibition activity against B. cinerea, S. aureus(P<0.05), the strain RLEFR010 had significant differences statistically for microbial inhibition activity against E. coli and S. aureus(P<0.05),the strain RLEFR002 had significant differences statistically for microbial inhibition activities against B.subtilis and S.aureus(P<0.05),the strains, RLEFR015, RLEFR010, RLEFR002, belonging to Fusidium sp. were strong bioactive isolates. The endophytic fungi isolated from the host showed diversity and antimicrobial activities, and majorities of the strains isolated from the host had antimicrobial activities against pathogens, inclined towards being more antagonistic to S. aureus and B. subtilis, and all that indicated that endophytic fungi from G.uralensis have important resource value.
Mechanism of plant tolerance to heavy metals enhanced by arbuscular mycorrhizal fungi
Shuangshuang LIN, Xiangwei SUN, Xiaojuan WANG, Yuanyuan LI, Qiaoyu LUO, Li SUN, Liang JIN
2013, 7(3): 365-374.
[Abstract](2332) [PDF 562KB](528)
Arbuscular mycorrhizae (AM) are the symbionts between AM fungi and plant roots in natural and artificial ecosystems. AM symbionts could decrease the harmful stress from heavy metals and regulate the heavy metals uptake and translocate to their host plants. In order to discover the physiological and molecular mechanism of heavy metals tolerance induced by AM fungi, the function and strategies of AM symbionts were discussed in this paper: 1) the fungal hyphae could immobilize heavy metals and restrict the translocation of heavy metals from roots to shoots; 2) chelating substances could immobilize heavy metals; 3) AM fungi could promote the nutrient acquisition to host plants; 4) AM fungi could regulate the distribution of heavy metals in host plants; 5) AM fungi could influence the antioxidative enzymes system activity and hormones in host plants; 6) the molecular mechanisms that AM fungi regulate heavy metal uptake and translocation. On the basis, this study focused on the possibility of using the system of AMsoil microbiologyhost plant for remediation of heavy metals polluted soil in future.
2013, 7(3): 375-375.
[Abstract](893) [PDF 225KB](1027)
Bulking strategies for genetic diversity analysis of annual ryegrass based on SSR markers
Yongcong LUO, Xiao MA, Xinquan ZHANG
2013, 7(3): 376-382.
[Abstract](1578) [PDF 548KB](428)
Since Annual ryegrass (Lolium multiflorum) belongs to the typical crosspollinated species, the sampling strategies are closely related to the authenticity and the efficiency of molecular genetic diversity analysis. Two Annual ryegrass varieties, Changjiang No.2 and Tetragold were selected and their bulked DNA samples obtained from 5, 10, 15, 20, 25 and 30 individual plants respectively. The result of genetic diversity analysis based on simple sequence repeat(SSR)markers showed that there were no differences in the PIC index among seven sampling methods, PIC reached the highest when bulked plant sample were 20. The number of average allele and the alleles, types of per SSR loc increased along with the plant number in the bulked plant samples increasing, which kept relatively steady when bulked plant samples surpassed 20 (including 20) plants, meanwhile the SSR banding patterns were relatively uniform. The bulked samples 20 were able to detect the most high frequency (10%) alleles with excellent reproducibility, if disregard the undetection of rare alleles (10%). It could be concluded that 20 individual plants was the suitable sampling size in genetic diversity analysis of annual ryegrass based on SSR markers.
Effects of temperature on seed germination characteristics of eight wild Poa germplasm
Jiayuan HE, Jingting WANG, Xiaoming BAI, Qin DONG, Youwei LV
2013, 7(3): 383-389.
[Abstract](1828) [PDF 430KB](333)
In order to provide the foundation for the introduction, domestication and utilization of wild Poa, six constant temperature treatments and two variable temperature treatments were employed to investigate the optimum temperature range on seed germination of eight wild Poa varieties. The results showed that the germination rate, germination potential, germination index, seeding length, root length and fresh weight of these varieties first increased then decreased with increasing temperature at constant temperature range of 10-35 ℃. The maximum germination rate occurred between 20-30 ℃ for the constant temperature treatment, the initial germination time was 4-5 days, the minimum occurred at 10 ℃ with the initial germination time between 11-14 days, which was 6-10 days later than the maximum germination rate. The germination rate, germination potential, germination index were taken as the primary parameters for optimal germination temperature selection, with reference of frond and root length, and fresh weight, the optimal germination temperatures of P.poophaqorum, P.pratensis and P.micrandra were 20 ℃ at constant temperature treatment, while those of P.pratensis(Xinglongshan), P.pratensis(Sunnan), P.pratensis(Weiyuan), P.pratensis(Tianzhu) and P.sphodylodes were 25 ℃ at constant temperature treatment. For most of the tested seeds, higher constant temperature favored the growth of frond, while lower (20 ℃) constant temperature or variable temperature favored the growth of root. Parameters at 5/20 ℃ and 10/25 ℃ variable temperature treatments were lower than their counterparts at 20 ℃ and 25 ℃ constant treatments.
Study on character of annual seeds yield, soil seed bank and seedling recruitment of Seriphidium transiliense
Weihua LU, Aitian REN, Jiejing YANG, Guili JIN
2013, 7(3): 390-396.
[Abstract](1527) [PDF 478KB](276)
Seriphidium transililense seeds yield was observed for three years (2007-2009), and the character of soil seed bank and seedlings recruitments were analyzed. The result showed that fence and climate affected seed yield of seeds. Seed yield inside fence is higher than outside fence significantly, and fluctuating of seed yield is more acutely in different years because of climate change, and shows 200720092008. Seed yield and weight of single S.transililense seedling are very sensitive to fence and climate change, and have significant difference inside, outside fence and in different years(P0.01), the seed mode does not change significantly. The seed germination rate has significant difference(P0.01), but there is no difference between years(P0.05). The germinable seeds of soil seed bank have dramatic changes and have significant differences in the annual and fences inside and outside, seedlings emergence quantity inside fence is larger than outside, but there is no significant difference in three years. The survival rate of seedlings is very low in three years and inside, outside the fence, but fences can significantly increase seedling survival rate. The conversion rate of every stage is relatively low from seed, soil seed bank, seedlings to seedling recruitment, the life story of S. transililense showed significant r strategy.
Diurnal changes of photosynthetic characters of four Juglans regia cultivars
Jianwei ZONG, Yuhua YANG, Fengling YANG, Yahong LIANG, Duling LIU, Hailan ZHU
2013, 7(3): 397-401.
[Abstract](1298) [PDF 415KB](298)
Diurnal changes of photosynthetic characteristics in four Juglans regia cultivars were studied by LI6400 portable photosynthesis analyzer for a theoretical basis of higheryield,higherquality and standardized production .The results showed that the diurnal changes of Pn in the four cultivars, all exhibited double peak curve and significant lunch break phenomenon at 14:00; Photoinhibition of Qiangtele and Zhonglin5 occurred earlier than Luguang and Zha343.There was a significant positive correlation between Pn and PAR of four cultivars in Juglans regia , however, their correlation coefficient was different, correlation coefficient descending order: Zha343>Qiangtele>Luguang>Zhonglin5
Study on diurnal variations of photosynthesis and response to light of Mesona chinensis
Jian DENG, Xiaohui LI, Yingyi LUO, Pinggang ZHANG, Fengqiong GAN, Liangbo LI, Rongshao HUANG
2013, 7(3): 402-408.
[Abstract](2639) [PDF 490KB](354)
In order to study the photosynthetic characteristics of six germplasm of Mesona chinensis for exploring suitable planting model, LI6400XT portable photosynthesis system was used to measure diurnal dynamics of the photosynthetic characteristics, lightresponse curve of photosynthesis,and chlorophyll content was measured with spectrophotometry. The results showed that stomatal and nonstomatal factors played a positive role in the change of photosynthesis of Sanjia Mesona and Xiaba Mesona, while stomatal factor induced the changes of photosynthesis of the others. Light compensation point (LCP) of six germplasm of Mesona size order is Lingshan smallleafSanjia MesonaXxiaba MesonaPaitan MesonaLingshan bigleafVietnam Mesona and light saturation point (LSP) size order is Lingshan smallleaf Xiaba MesonaVietnam MesonaPaitan MesonaLingshan bigleafSanjia Mesona. Variance analysis shows that LCP and LSP of lingshan smallleaf are much higher than those of other Mesona (P0.05), and it is adaptive to the environment with high level of light intensity. LCP of Vietnam Mesona is lowest (P0.01), showing that it was shadetolerant and attempted to plant under forest. There was a significant positive correlation between chlorophyll content and Pn,max, and daily variation regularity of Pn was caused by environmental factors and internal factors. The study provides theoretical basis for exploring Mesona planting model, reasonable standardized planting and screening of improved strains.
Effects of leaf cytokinin induced by root nitrate absorption on the continuous regrowth of defoliated ryegrass
Jia WANG, Xiaoling WANG
2013, 7(3): 409-417.
[Abstract](1483) [PDF 539KB](314)
The effect of root nitrate (NO3-) absorption on the continuous regrowth of ryegrass under frequent defoliation was studied in this experiment. Results showed that frequent defoliation caused a significant decline in root bleeding sap quantity, NO3- and cytokinin content in leaves, as well as biomass of newly grown leaves when no external nitrate source was available. The absorption of NO3- by roots easily increased root bleeding sap quantity, NO3- content in roots, accumulated NO3- quantity in bleeding sap, NO3- and cytokinin content in leaves, as well as biomass of newly grown leaves whenever the external nitrate source was supplied after the first or third clipping. The stimulation effect of leaf cytokinin on the continuous regrowth of defoliated ryegrass is not depending on the cytokinin transported from root to leaf, but on the synthesis of leaf cytokinin induced by the NO3- transported from roots to newly grown leaves.
Gender differences analysis of apparent traits of Humulus scandens in response to temperature in the vegetative growth stage
Jing DUAN, Jinping LIU
2013, 7(3): 418-422.
[Abstract](1355) [PDF 391KB](305)
Through determination of the vegetative growth duration of individual male and female Humulus scandens, the data of quantitative traits of components(root, stem, leaf), fresh weight, dry weight and biomass allocation, this paper analyzes the impact that temperature has on the growth characteristics of male and female Humulus scandens during their vegetative period under culture conditions with temperature of 15 ℃, 20 ℃, and 25 ℃. The results show that temperature has a significant influence on the vegetative growth duration of Humulus scandens (P0.01). Female plants are more sensitive than male plants to temperature, temperature also significantly affects the data of quantitative traits of components (root, stem, leaf), fresh weight, and dry weight and the same influence can be seen on the constitution and total biomass of the single female and male Humulus scandens in the vegetative growth stage. Material basis for reproductive growth is supported by male and female Humulus scandens, through reducing leaf biomass and increasing root biomass respectively.
Analysis of the key stress factors in winter rape under simulated salinityalkalinity mixed condition
Yaozhao XU, Wancang SUN, Xiucun ZENG, Caixia LI, Xiwang ZHOU
2013, 7(3): 423-429.
[Abstract](1190) [PDF 431KB](385)
Strain index of seed germination rate、seedling leaf cell membrane permeability、MDA content、proline content、soluble protein content and root activity of Longyou No. 6 seeds and seedlings were determined between A factors of 4 kinds of salt for NaCl, Na2SO4, Na2CO3 and NaHCO3, composed of salt mole ratio for A1 (1∶9∶9∶1), A2(1∶1∶1∶1), A3(9∶1∶1∶9) and A4(1∶1∶9∶9) and B factors of 5 kinds of salt concentration for B1 (10 mmolL-1), B2 (20 mmolL-1), B3 (30 mmolL-1), B4 (40 mmolL-1)and B5 (50 mmolL-1) of the double factors. Twenty kinds of salinity and different pH of saline conditions were simulated to treat winter rape No.6 seeds and seedling 7D. The results showed that 20 kinds of salinity were from 10 to 50 mmolL-1 and pH was between 8.50 and 10.24. Seed germination rate, seedling root activity and soluble protein content were decreased and leaf cell membrane permeability, MDA content and proline content were increased with the increasing of the concentration of salt treatment. The degree of increase and reduction became higher among A1 to A4 in turn. The different salt composition in treatment reached significant difference (P0.05). All stress effect factors under saline mixed conditions were caused by salinity (Na+), pH, CO32- and Cl-. Stress factors of salinealkali and strain index of Longyou No. 6 seeds and seedlings had high linear correlation. The dominant factors of winter rape stress were pH、salinity (Na+)、CO32- and stress effect on winter rape Longyou No. 6 of Cl- could not be ignored.
Changes of community characteristics in the legume/grass pasture in different year after establishment
Hai LI, Chunling ZHU, Shazhou AN, Jiangfei MA, Haifeng DENG
2013, 7(3): 430-435.
[Abstract](1398) [PDF 508KB](350)
The experiment was conducted to measure the changes of species number, yield and community characteristics in the pasture where mixed with 6 species of gramineae or leguminosae and lied in the degraded meadow steppe of Zhaosu piedmont in Xinjiang, aiming to provide theoretical basis and practical experiences for the improvement of degraded rangelands and construction of artificial pastures. The results showed that the species composition and community structure changed fundamentally compared with the control. The planted species in the pasture occupied predominate position and its aboveground biomass was significantly higher than that of the control (P0.05). The maximum biomass (about 2 500 gm-2) appeared in the middle of July with over 15 days ahead of natural grassland, and it was 2.54 times than the control. The original grasses appeared successively resulting in species richness, diversity and evenness increased collectively along with the extension of years, and the important value of plant pasture declined. There was decline trend for the species of legume, but the species of grasses increased. The productivity in the pasture showed the trend of declination, however it maintained much higher.
Different grass community development and its effects on weeds in the apple orchard
Jiancun KOU, Wenquan YANG, Mingyu HAN, Xiaojuan YANG, Muyu GU
2013, 7(3): 436-446.
[Abstract](1477) [PDF 550KB](302)
The study was conducted on the community development of the grasses planted between the apple lines in the spring in the 1yearold apple orchard and their effects on the community development of the weeds. The natural weed community was taken as the control. The results showed when the grasses were planted in the spring in the Guanzhong Area of Shannxi, Trifolium repens, T.pretense, Lolium perenne, Festuca rubra and Festuca arundinacea quickly germinated and grew fast and developed into the sward in short time. There were less species, low density and coverage of the weeds in their community and with better effects on controlling the weeds. Poa pratensis, Agrostis stolonifera, Lotus cornioulatus, Dichondra repens and Cynodon dactylon were hard to germinate and grow could not come into sward until the autumn. They could not effectively control the weeds at that time. In the second year after planting, all the grasses except for D.repens and C.dactylon had the long green period, turning green in March and scorching no earlier than November. The creeping stem of D.repens grew horizontally at a medium speed and vertically kept 10~15 cm in all seasons. And it well covered the ground and without cutting in the growth season, the maintenance cost was less. T.repens, T.pretense, L.cornioulatus grew with a right speed and the cutting was dependent on their own. L.perenne and F.arundinacea grew quickly with high yield and was necessary to cut once in the first year, the cutting frequencies were dependent on the practical situation in the second year. A.stolonifera and F.rubra grew slowly and the cutting frequencies should be less than A.stolonifera and F.rubra. C.dactylon turned green later and scorched earlier than others. In addition, it grew horizontally and levelly too fast and was not good to plant it in the apple orchard. In conclusion, the suitability of grasses in the apple orchard was different and their growth characters were important for the orchard management. The coverage was highly relative to their controlling effects on the weed community development.
Effects of light intensity on growth and physiological characteristics of Sedum sarmentosum during establishment stage
Lei ZHANG, Haidong JIANG
2013, 7(3): 447-451.
[Abstract](1464) [PDF 430KB](314)
Effects of different light intensities (100%, 77%, 47% and 23% sunlight) on growth and physiological characteristics of Sedum sarmentosum during establishment stage were studied through artificially shading treatment. The results indicated that within the light intensity range in this experiment, S.sarmentosum could grow normally and showed good morphological plasticity. Low light intensity induced more new shoots and leaves, smaller diameter, longer shoot and internode. Compared with 100% sunlight, shading promoted plant dry matter accumulation and more energy distribution to the growth of stem. All these changes help capture more light to adapt to low light enviorenment. In addition, shading increased plant water content and soluble protein content, and reduced soluble sugar content. Photosynthetic pigment content increased significantly only on 23% sunlight condition which caused dramatic negative influence to root development, and slight decrease of plant dry weight contrasting to 47% sunlight. It suggested that moderate shading could accelerate covering rate in establishment, but light intensity lower than 23% was not recommended.
Effects of drought on grassland turning green period in Inner Mongolia
Xinghua LI, Suhua CHEN, Fang HAN
2013, 7(3): 452-456.
[Abstract](1230) [PDF 392KB](308)
Taking the relationship between April precipitation and grass turning green time into consideration, direct loss assessment caused by the drought on the grass turning green was studied. The results showed that grass turning green and April precipitation were negatively correlated, and the correlation coefficient was -0.185. If April precipitation reduced by 30% to 50%, grass turning green time will be delayed 5 to 15 days in the desert steppe. When April precipitation reduced over 50%, grass turning green time will be delayed 10 days in the typical steppe and meadow steppe. Correspondence of drought grade and cost of the loss between the feeding and drinking water was established, along with the fulfillment of quantitative assessment of direct economic losses of drought on the grass turning green. The assessment model is in line with the regularity of grass pasture growth and livestock production characteristics, a case assessment may reflect livestock actual loss extent. This model is able to apply on assessing influence of drought on the grassland animal husbandry service.
Situation of the black goat in winter in Wumeng Mountain Area
Fang DING, Jiawen LIU
2013, 7(3): 457-460.
[Abstract](1176) [PDF 403KB](274)
Grassland and animal industry plays an important role in economic development and improvement of ecological environment in Guizhou Province. In order to improve the productive efficiency of breeding black goat in Guizhou Province, a farm surveys and lab examination to analyze black goat overwintering were conducted in Hezhang County. The results showed that there were 19.3% mortality of black goats in winter. The mortality of goat lamb was 31.0% which was the highest, while finishing goats were as low as 3.8%. Mean body weight loss of black goat was significantly 11.4% in winter and it was the highest in January. The abortion of pregnant black goat was 28.6%. The experimental results showed that the positive rates of Toxoplasma gondii, Chlamydia and brucella in the pregnant black goats were 0. It showed that the abortion of pregnant black goat in Hezhang County was not caused by Brucella, Chlamydia, and Toxoplasma gondii. The improvement of shed facilities, ration nutrition and herd organization could reduce winter mortality, lower abortion rate, and avoid body weight loss of black goat in winter. The black goat overwintering problem could be solved in Hezhang County and the productive efficiency of grassland and animal industry could be improved.
Laboratory screening of green pesticides for controlling of turf pest Prodenia litura
Mingzhang CAO, Weifeng ZHU, Cunhuan LI
2013, 7(3): 461-464.
[Abstract](1382) [PDF 390KB](433)
To screen green pesticides for the management of Prodenia litura, laboratory efficacies of 20 green pesticides belonging to five different chemistries were evaluated on the 3rd instar larvae of P.litura using leafdip method. Results showed that efficacies of seven pyrethroids (lambdacyhalothrin, cyfluthrin, bifenthrin, betacypermethrin, cypermethrin, fenvalerate and fenpropathrin) commonly used in agriculture were lower than that of conventional organophosphorus insecticide chlorpyrifos, two novel pyrethroids (transfluthrin and tetramethylfluthrin, mainly used in vector control) had higher or equal activity compared with chlorpyrifos. Lufenuron, chlorfluazuron, hexaflumuron, tebufenozide, indoxacarb, chlorfenapyr and emamectin benzoate were the seven most effective to P.litura in laboratory among twenty tested green pesticides. Belonging to five different modes of action, these seven insecticides can be used as green pesticide candidates for the control of turf insect pest P.litura and served to be further studied in field.
Causes and harmfulness of management right dispute of grassland and its solutions in the Tibetan areas of China
Hongwei HOU, Zhenggang GUO
2013, 7(3): 465-470.
[Abstract](1141) [PDF 487KB](313)
The right dispute of grassland is a serious threat to the social stability and sustainable development of Tibetan areas in China. This study presented the causes of the right dispute of grassland from the interest drive, vague boundary line of some grassland, group standard and dispute settlement mechanism, and pointed out that the right dispute of grassland threatened the life, property safety of herdsmen and social stability, encouraged the Tibet customary law to resurge, reduced the governing ability and the government's credibility. The paper also put forward a longterm approach to solve the right dispute of grassland in Tibetan areas, in which the national laws was Orientation, the readjusting vague boundary line of some grassland was basis, popularizing law was strategies, and gun seizures by government was measures, which would guide the Tibet areas to allround social legalization and benefit the social stability and sustainable development.
Achievements of the alfalfa industry in last decade and priorities in next decade in China
Qizhong SUN, Zhu YU, Chunhui MA, Chuncheng XU
2013, 7(3): 471-477.
[Abstract](1305) [PDF 475KB](369)
The development of alfalfa industry over the past 60 years in China could be divided into five stages. In the recent decade, the technology driver of alfalfa began to be promoted, the industrial structure became more clear, the planting area of alfalfa continue to expand, production and processing enterprises emerged constantly with continuous improvement of social status and role of alfalfa. At the same time, the contradiction between supply and demand of alfalfa continued to exacerbate and with increasing pressure on the lack of technological innovation, resource constraints, ecological safety and interface coupled of alfalfa. In the year ahead, the strategic position of sustainable development, scientific and technological innovation, cultivation of new varieties and seed industry of alfalfa should be strengthened for the promotion of the modernization of alfalfa industry and enhancing the development level of alfalfa, cow's integration, biotechnology and bioeconomy of alfalfa.
The social, economic, and ecological benefit of deserticulture in Ningxia
Zengwu XIE, Kun WANG, Shixiong CAO
2013, 7(3): 478-483.
[Abstract](1696) [PDF 458KB](285)
Ningxia is one of the most serious desertification regions in China and remain relatively underdeveloped in terms of economy and social development. In the process of combating land desertification, a new mechanism was established in 1990s, socalled governmental guiding, projects motivating, market orientation and enterprises and the whole society participating. The local government promotes the role of the typical model of radiation effects. A policy vigorously favors desert sunlight greenhouses, Chinese herbs planting, and sowing watermelon on pressure sand. Ecological improvement and favorable mechanism made the Ningxia province became the first province where sandified and desertified lands became smaller. The deserticulture in Ningxia showed that the effective combination of ecological restoration and economic development, as well as ecological compensation can achieve positive interaction with natural environment, social economy and escape the poverty trap. Deserticulture brought economic benefit and ecological benefit, promoted the local people's enthusiasm of environment resource protection. The deserticulture in Ningxia provides beneficial experience to other povertystricken areas and countries.