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2009 Vol.26(8)

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2009, 3(8): 1-5.
[Abstract](1149) [PDF 688KB](1519)
Pastoral agriculture system plays an important role in food securityThought on melamine milk powder crisis
2009, 3(8): 6-9.
[Abstract](1385) [PDF 651KB](980)
There is a continuously increasing requirement of animal foods because of rapid increase both in human population and people's living level. However, there is still a structural defect of agricultural system and an unavailability of efficiently administrative system and consequently, the situation of food security is gradually becoming serious. Based on the historical lessons and successful experiences of the domestic and other countries for reference, the coupling forage production with livestock production supplies a basis of agricultural system to food security and the pastoral agriculture system supplies an irreplaceable platform to forage and livestock coupling, which is an important indicator of agricultural modernization. Moreover, an administrative department with both multifunctional ability and simplified organization, which is positively corresponding to four production levels of pastoral agriculture system, will supply systematic guarantee to food security. In China, thinking pattern of putting food security on Grain Food is the Key policy should be given up and the pastoral agriculture system should be set up as the basis for food security.
Niche characteristic of herbages in artificial sandfixing communities in Horqin sandy land
2009, 3(8): 10-16.
[Abstract](1568) [PDF 627KB](748)
By using Levins index of niche breadth and Pianka index of niche overlap, the niche characteristics of herbaceous species on mobile sand dune and in different artificial sandfixing communities were studied. The results showed that the niche breadth of species varied in different habitats, Agriophyllum squarrosum, Setaria viridis and Digitaria ciliaris had the widest niche breadth on mobile sand dune and in Hedysarum fruticosum community and Salix gordejevii community respectively, while the niche breadth of Corispermum candelabrum was the widest in Caragana korshinshii community and C. microphylla community. The species with wide niche breadth had large niche overlap in each community, but there were also large niche overlap between the species with low niche breadth, which showed from another point of view that environment and resources had high spatial heterogeneity in different sandfixing communities. The difference of niche breadth and niche overlap of the same species in different communities showed that the feature of regional environment among the communities was different.
Cloning and analysis of a novel DREB gene of Glycine soja
2009, 3(8): 17-23.
[Abstract](1741) [PDF 945KB](681)
The total RNA in leaf of Glycine soja was treated as cyclostyle. The degenerate primers were designed based on the conservative amino acids sequence of DREBP/AP2 domain from other dicotyledonous. A cDNA fragment of 191bp from G. soja was obtained by touchdown PCR and nestedPCR. Based on this sequence, the nest primers were designed, than 3and 5cDNA sequences were obtained by 3and 5 rapid amplification of cDNA ends PCR (RACEPCR), and the complete DREB gene was constructed in G. soja (designated as GsDREB). The whole sequence of GsDREB was 1191 bp open reading frame (ORF) encoding a 395 amino acids, without any intron. Amino acid analysis indicated that, the predicted GsDREB protein contained a Nterminal nuclear localization signal (NLS), and a putative AP2 DNAbinding domain containing 58 conserved amino acids. Alignment of multiple showed that GsDREB had much similarity with AtDREB2, so it might be a member of DREB2 subgroup of DREB family.
CBERS and MODIS data based Grassland resources monitoring and evaluation
2009, 3(8): 24-33.
[Abstract](1653) [PDF 2572KB](724)
During the establishment of rules and regulations, including Guideline for Remote Sensing Investigation on Grassland Resources,Operation Rules and Regulations for Grassland Resources Management Planning and Rules of Mapping Data for Grassland Resources Management Planning, the interpretation of remote sensing data of grassland resources was studied using CBERS data and the humancomputer interaction methods were used to renew the map of grassland type with GIS software, and then the renewed maps of grassland resources were used to achieve the dynamic monitoring on grassland resources together with EOS/MODIS data.
RS and GIS based space pattern analysis of grassland landscape in Tianzhu
2009, 3(8): 34-39.
[Abstract](1501) [PDF 1331KB](769)
Based on RS and GIS technologies and landscape ecology theory, the grassland landscape patterns in Tianzhu were analyzed in terms of different landscape areas, percentage of landscape and number of patches by using LandsatTM image in 2006. Grassland and forestland were the main landscape types and grassland was the matrix in the research area. The landscape space distribution in terms of altitude, aspect and slope was featured with remarkable vertical patterns from valley to hilltop by the sequence of residential and industrial land, cultivated land, water area, grassland, forestland, and unused land, the landscape types also regularly distributed. in different aspects and slopes.
SSM/I based model inversion of snow depth and temporal and spatial distribution of snow cover on the on the eastern QinghaiTibet Plateau
2009, 3(8): 40-46.
[Abstract](1259) [PDF 1398KB](627)
Snow disaster is one of the main meteorological disasters restricting the livestock production and sustainable development of pastoral area. The snow depth model was inversed and the distribution and snow depth of snow cover were estimated in eastern QinghaiTibet Plateau by using SSM/I daily brightness temperature data and corresponding measured ground snow depth from 79 meteorological stations in the research area from October to next March during 1995 to 1996, 2000 to 2001 and 2005 to 2006. Results showed that the area of snow cover increased at intervals of one month or ten days in 3 snow seasons and reached the maximum during December to January, and then reduced. The depth of snowcover in each snow season was less than 5 cm, and basically, it was not over 10 cm in October, next February and March. Based on the snow depth data at intervals of ten days in 3 snow seasons, the snow cover area normally increased at the beginning and then decreased, in which, the change of snow area that snow depth was below 5 cm was the largest, and that above 10 cm was the smallest. In 3 snow seasons, the snow cover areas with depth from 5 to 10 cm mainly distributed in Yushu and Guoluo prefectures in the south of Qinghai Province.
Study on the nutrition value of herbage protein tofu
2009, 3(8): 47-51.
[Abstract](1770) [PDF 558KB](803)
In order to provide further scientific basis for the transformation of the new technology for herbage protein tofu making, 3 kinds of alfalfa protein tofu and 3 kinds of white clover protein tofu were used to test the contents of dry matter, crude protein, lipid, total sugar, insoluble dietary fiber, total ash, calcium and carotenoid, and further, the amino acids contents of protein were determined as well. With the ordinary tofu as control, nutrition values of 6 kinds of herbage protein tofu were evaluated. The results showed that the crude protein and total sugar contents of 6 kinds of herbage protein tofu were similar to the control. The herbage protein tofu was lower in lipid contents and richer in insoluble dietary fiber, calcium and carotenoid contents. The total amino acids contents and the amino acid scores of herbage protein tofu were obviously higher than ordinary tofu. Lysine was the only restrictive amino acid for 4 kinds of herbage protein tofu. Lysine and sulfur amino acid were the restrictive amino acid for the rest of 2 kinds of herbage protein tofu. The herbage protein tofu was more balanced than ordinary tofu in their essential amino acid compositions, in which, the white clover tofu was the best.
SEM observation on anatomical structure of Elytrigia elongata and E. intermedia
2009, 3(8): 52-56.
[Abstract](1415) [PDF 764KB](670)
The anatomical structure of root, stem, leaf and rhizome of Elytrigia elongata and E. intermedia was examined under the scanning electron microscope (SEM). The anatomical structure of root transverse section was consisted with epidermis, cortex and stele. The number of root hairs appeared in the epidermis, and the endodermis cell had 5 thickened walls and was the horseshoeshaped in the transverse section. Two circles of vascular bundles and a central pith cavity showed in the stem and rhizome morphology. The leaf was differentiated into 3 parts, including epidermis, mesophyll and veins. The epidermal cell consisted with long cells, stomata cells, bulliform cells and subsidiary objects. Two species had significant difference in leaf epidermis micromorphology, 3 to 4 rows of papilla were distributed in the costal zone of E. elongata leaves, but 3 to 4 rows of prickle hair were distributed in the same areas of E. intermedia leaves. In addition, the welldeveloped similar aerenchyma was found in the root cortex and further research is necessary to find out the cause.
Dynamic change of marsh landscape patterns and its driving forces in Maqu
2009, 3(8): 57-62.
[Abstract](1442) [PDF 1120KB](691)
By using RS and GIS techniques, landscape ecological method, index of LAND, SHAPE, PD, the change of wetland landscape pattern in Maqu was systematically analyzed from 1995 to 2006. The results shown that the reduction tendency of the wetlands was obvious under the background of climate warming up, and the patch number significantly decreased for those area smaller than 10 hectares. At the same time, reduction in landscape shape index was mainly due to the regularly of larger patches. The results of this study could contribute to the protection of alpine marsh wetland
Effect of fertilization on the caloric value and morphological properties of Miscanthus floridulus
2009, 3(8): 63-67.
[Abstract](1818) [PDF 556KB](930)
The effect of nitrogen fertilizer, phosphate fertilizer and potassium fertilizer on the caloric value, ash content and morphological properties of Miscanthus floridulus were studied. The orthogonal design was used to determine the effects of N, P and Kcombinations on caloric value, ash content, plant height, stem diameter, ratio of stem to leaf and yield .The results showed that differences of caloric values in leaf, ash quantity of leaf and stem, plant height, stem diameter among different combinations were significant except the yield. The best fertilizer combination was urea (300 kg/hm2) + superphosphate(600 kg/hm2)+ KCl (50 kg/hm2) and the higher caloric value and lower ash content could be reached. Under the combination of urea (300 kg/hm2) + superphosphate(600 kg/hm2)+ KCl (50 kg/hm2), the better morphological properties could be reached.
Asexual reproduction component and its diversity of wild Humulus scandens in Nanchong
2009, 3(8): 68-71.
[Abstract](1324) [PDF 467KB](764)
The asexual reproduction components of 4 populations of Humulus scandens in Nanchong of Sichuan Province were studied and the results showed the coefficient of variation (cv) of petiole length and the leaf radius were 43.9% and 27.54% respectively. The adult plants had a great difference in cv between their secondlevel stem, the thirdlevel stem and the node segment length. For the 4 populations, the cv of secondlevel stem were 86.33%, 91.46%, 76.36% and 51.20% respectively; as the thirdlevel stem, they were 81.83%, 66.44%, 52.35% and 26.82% respectively. The cv of node segment length were 38.17%, 49.77%, 32% and 48.34% respectively. Moreover, the inflorescence length, floret number, inflorescence radius and floret radius were obviously different.
Multiscale response of plant diversity in grassland ecosystem to anthropogenic disturbances
2009, 3(8): 72-80.
[Abstract](1575) [PDF 1017KB](931)
Anthropogenic disturbances are one of the important factors which cause the variations of plant diversity in grassland ecosystems. Plant diversity depends on the ecosystem structures and processes taking place over a range of spatialtemporal scale. The significant dominant effect of plant diversity can only be expressed in particular spatialtemporal scale. The scale features of plant diversity and the largescale effect of anthropogenic disturbances determine the complexity and arduousness of plant diversity conservation in grassland ecosystem. This paper discussed the response patterns, processes and ecological consequences of plant diversity to various anthropogenic disturbances at different spatialtemporal scales, confirmed the important role of scale issues in the research of plant diversity, and probed into the causes of plant diversity changes and its related response mechanism under anthropogenic disturbances in grassland ecosystem, as well as their implications in the conservation and rational utilization of plant diversity, and grassland ecosystem sustainable development.
Relationship between the aboveground dry matter accumulation of alfalfa and the effective accumulated temperature in the first cutting
2009, 3(8): 81-86.
[Abstract](1808) [PDF 623KB](620)
The results of field experiments on relationship between dry matter yield of the fouryear alfalfa in the first cutting and 5 ℃ accumulated temperature indicated that 1) The dry matter growth pattern of different parts of alfalfa varieties was same. The order of the production potential of dry matter, maximum growth rate, average growth rate were whole plant stem leaf. But the ranges of the effective accumulated temperature for the maximum growth rate and average growth rate were different. The maximum growth rates of whole plant, stem and leaf were reached while the effective accumulated temperatures were 504.72 to 609.45 ℃, 574.47 to 643.91 ℃, 444.53 to 543.25 ℃ respectively. And for the average growth rates, they were 384.61 to 716.54 ℃, 424.48 to 773.36 ℃, 320.42 to 642.48 ℃; 2) The dry matter growth of different alfalfa varieties was different. For whole plant, stem and leaf of Lobo, Amerigraze 401 and Meiguozajiao, their potential dry matter growth, maximum growth rates and average growth rates in peak of growing season were higher.
Effect of temperature and drought stress on seed germination of three forage species
2009, 3(8): 87-92.
[Abstract](1578) [PDF 880KB](755)
The seeds of Heteropogon contortus, Dactylis glomerata and Festuca arundinacea were used for seed germination tests under temperature and drought stress. Seed germination rate, germination vigor and germination index of 3 forage species treated with 3 different temperatures and 4 different drought stress levels were measured. The results showed the seeds of H. contortus could germinate under the room temperature in natural environment. The seedling emergence of H. contortus was 2 to 3 days earlier than D. glomerata and F. arundinacea under different temperatures and PEG. The germination index of H. contortus was higher than D. glomerata and F. arundinacea. Low drought stress was helpful for the seed germination of H. contortus, but unfavorable when drought stress was over -3 Pa. The adaptability of H. contortus to dry and hot valley mainly depended on the adaptability after germination.
Impact of total flavone of alfalfa on the lipid metabolism and oxygenderived free radicals in mice
2009, 3(8): 93-96.
[Abstract](1589) [PDF 539KB](776)
The impact of total flavone of alfalfa (TFA) on the lipid metabolism and oxygenderived free radicals in mice studied. After the mice were drenched with TFA for seven days, the contents of triglyceride (TG), low density lipoprotein (LDL) and high density lipoprotein (HDL) in blood as well as the activities of superoxide dismutase (SOD) and malonaldehyde (MDA) in liver and ren were determined by biochemical methods. In TFA group, the contents of TG and LDL in blood and MDA in tissues were obviously reduced(P<0.05), but HDLC content was high, and the activities of SOD in tissues were significantly increased(P<0.05). So it could be concluded that TFA could perform the function of reducing TG and LDL as well as preventing angiosclerosis, and at the same time, it could obviously inhibit the damage from oxygenderived free radicals and prevent lipid peroxidation.
Biological effect of 60Co radiation on Echinochloa crusgalli and Pennisetum glaucum
2009, 3(8): 97-100.
[Abstract](1500) [PDF 816KB](783)
The dry seeds of Echinochloa crusgalli and Pennisetum glaucum were irradiated by 60Co rays with 10, 20 and 30 Gy. The results shown that 60Co ray treatment reduced the germination rate, increased seedling height with different degree. Different chromosome aberrations observed in root tip cells, such as single micronucleus, double micronucleus, single bridge and double bridge. Micronucleus and chromosome aberrations rate were rising with the increase of 60Co ray dose. E.crusgalli was more sensitive to 60Co ray radiation than P.glaucum irradiated by.
Grey connection analysis of alfalfa yield and climate factors
2009, 3(8): 101-106.
[Abstract](1713) [PDF 567KB](674)
By using grey connection analysis, the connection degree between alfalfa yield (allyear yield and each stubble yield) and climate factors (including accumulated temperature above 5 ℃, precipitation, sunshine hours, mean temperature, mean maximum temperature, mean minimum temperature and relative humidity) was studied in the rainfed farming area. Results were as follows: association degree of yield of the first stubble with precipitation was the biggest, which was in the first ten day of May, the first and middle ten days of April, with effective accumulated temperature above 5 ℃ was the bigger, which was in the first and last ten days of March, and the first ten day of May; Climate factors of affecting on regrowth hay yield were primarily temperature index; Climate factors of affecting on total year hay yield was maximum temperature and minimum temperature most, which was in June, July and August, and precipitation, which was in April, May and June. Primary and lesser climate factors affecting on total year hay yield and every cutting hay yield, and effect of time period were different, therefore, corresponding measures were adopted in practice.
Study on the growth characteristic and relative feeding value of four varieties of Brachiaria decumbens in Southern Fujian
2009, 3(8): 107-111.
[Abstract](1509) [PDF 479KB](673)
The growth characteristic and quality analysis of 4 Brachiaria decumbens varieties were conducted for 3 years. The results showed that all varieties grew normally in southern Fujian. The blooming stage of Reyan No.3 and Reyan No. 6 was in the early and middle of June. The blooming stage of 2 hybrid varieties was later about 2 months than Reyan No.6. The annual fresh yield of Hybrid Mulato 1 was the highest and it was significantly different from that of Reyan No. 6 (P0.01). The crude protein content of Hybrid Mulato 1 was the hightest (9.38%) in tillering stage. The crude fat and calcium contents of Reyan No.6 were the highest. The relative feeding value of all varieties were around 100%. It suggested that Hybrid Mulato 1 could be widely extended in southern Fujian.
Effect of different treatments on seed germination of Kobresia bellardii
2009, 3(8): 112-117.
[Abstract](1588) [PDF 1171KB](726)
The study on the seed germination of Kobresia bellardii under different temperature (5, 10, 15, 20 and 25 ℃) and different concentration of three chemical solutions (NaOH, GA and CaCl2) was conducted. The result indicated that the temperature and three chemicals and concentration had significant effect on seed germination rate, germination index and shoot length (P<0.001). Moreover, the temperature contributed more to the seed germination than the chemicals. The germination temperature range was from 10 to 25 ℃, but the growth of shoot, germination rate and germination index were higher at 20 and 25 ℃ than those at 10 and 15 ℃. The higher chemical concentration promoted the seed germination rate and germination index at lower temperature, however, the lower chemical concentration was favorable to the seeds germination at higher temperature. Under 25 ℃, the best treatment was to soak the seeds in CaCl2 solution with a concentration of 5 g/L, the germination rate was highest and could reach 84%. At 20 ℃, to deal with the seeds in NaOH solution with a concentration of 20 g/L, the highest germination index (5.26) could be reached.
Comparative test of eight introduced alfalfa varieties
2009, 3(8): 118-121.
[Abstract](1476) [PDF 471KB](867)
A field comparative test of 10 alfalfa varieties introduced from Europe and domestic was carried out in Jilin Forage Experimental Station of Academy of Agricultural Sciences of Jilin Provience. The characteristics including growth rate, natural height, tiller number, fresh yield were tested. The results showed that there were significant differences in characteristics of growth and development among 8 varieties. The foreign varieties, including Titan, Luozuoma, Roquois and Kane had better performances and their yields were high. Meanwhile, they showed early regreenning and faster growth. In which, the yields of Titan and Luozuoma were higher. The crude protein content of Titan in the squaring stage was the highest and the second was Kane. It could be concluded that these 4 varieties were suitable for extension in Jilin Province.
Study on the total saponin measurement and variation in growth period of four legumes
2009, 3(8): 122-127.
[Abstract](1601) [PDF 955KB](700)
The colorimetric method was used for quantification of triterpene saponin with vanillin reagents as colorant, and the accuracy, reproducibility and stability were tested. The contents of total saponin in 4 legumes (Astragalus sinicus, Onobrychis viciaefolia, Lotus corniculatus and Coronilla varia) were determined with the above method. The results showed that the method was simple with high accuracy and reproducibility, and very stable within 25 min. The variation of total saponin contents of 4 legumes was not same. A. sinicus and O. viciaefolia in early flowering stage were proper for feeding livestock or hay making because of the low saponin content, high yield and excellent quality, meanwhile, these two legumes were better be used as material for saponin extraction in flowering stage because of the high saponon content and the highest yield. C. varia, remained lower saponin content and no ruminant distension of abdomen, was a highquality legume forage. The content of total saponin in leaf were much higher than in stem.
Relationship between the fall dormancy of alfalfa and activities of SOD and POD
2009, 3(8): 128-131.
[Abstract](1272) [PDF 448KB](616)
The experiment was conducted to explore the relationship between fall dormancy and superoxide dismutase (SOD) and peroxidase (POD) activities of alfalfa under short day (8 h light/16 h dark) condition. The results showed that SOD and POD activities increased with the increase of fall dormancy, and the fall dormancy alfalfa (Vernal) was the highest and followed by the semifall dormancy alfalfa (CW 502), and nonfall dormancy alfalfa (CUF101); SOD and POD activities of three different fall dormancy alfalfa increased with the elongation of growth period.
Effects of Interplanting cocksfoot and white clover as cover crops on the microclimate of apple orchard
2009, 3(8): 132-136.
[Abstract](1521) [PDF 937KB](711)
The effects of interplanting Dactylis glomerata and Trifolium repens as cover crops on the microclimate of apple orchard were studied. The results showed that the interplanting orchard grasses, compared with clean tillage, could improve the ground temperature, air temperature and air relative humidity in the apple orchard, especially, could decrease the ground and air temperature on the hot summer, keep the ground temperature in the cold winter and endautumn. And because the soil surface was covered with the grasses, the soil waterholding capacity and the soil organic matter could be increased, and the soil physical and chemical properties were improved as well. Therefore, a better suitable environment could be provided for the apple trees.
Effect of intercropping of corn with chicory at different densities
2009, 3(8): 137-140.
[Abstract](1592) [PDF 460KB](657)
By using quadratic saturation D optimum design, the test on the intercropping of corn with chicory at different densities was carried out. The regression models for predicting the corn grain yield and chicory fresh yield with corn and chicory densities were set up. Based on analyze of the models, the corn grain yield could reach 599 3.69 kg/hm2 when corn and chicory densities were 229 66 plants/hm2 and 111 851 plants/hm2 respectively. The chicory fresh yield could reach 106 014.51 kg/hm2 while chicory density was 258 834.3 plants/hm2 and the corn density negatively affected the chicory fresh yield. Take corn grain yield growing in step with chicory fresh production as target ,we optimality selected Regression models,we put forward 8 sets of corn, chicory coproduction technical proposal:corn grain yield is 5 475 kg/hm2,chicory fresh production is 82 500 kg/hm2,corn density is 43 446~50 499 stems/hm2,chicory 105 713~204 158 stems/hm2.
Discussion on the development of cropgrass system in the Three Rivers region of Tibet
2009, 3(8): 141-146.
[Abstract](1588) [PDF 733KB](725)
Grassindustry in agricultural area (threerivers region) must be developed in Tibet so as to adapt to the Tibetan development in the future. In double cropping system of threerivers area, the introduction of fodder production could adjust agricultural structure and waterheat pattern, and make the agricultural system more reasonable and environment conservation. Fodder production and grass growing could provide a lot of high quality forage for livestock production, and enhance vegetation coverage, reduce wind speed and soil loss. The development of grassindustry in agricultural area could alleviate the great livestock pressure in natural rangeland and slow down the grassland degradation. The development of fodder and livestock production industry could benefit the construction of special bases for livestock production, the economic development and then the income of herders. Therefore, grass system development in agricultural area was a key point to improving the sustainable development in threerivers region.
Effect of Apis mellifera on pollinizing effectiveness of Russian alfalfa
2009, 3(8): 147-151.
[Abstract](1373) [PDF 529KB](649)
It is a effective way to increase the seed yield of alfalfa by using pollinating insect, and for this purpose, the effect of Apis mellifera on alfalfa pollination was studied. The result indicated that the beak length of A. mellifera was 7.2 mm. It visited the flowers from 9:00 every day and the visiting peak period was from 12:00 to 18:00. The suitable temperature for the visiting was from 15 to 25 ℃, and the visiting speed was 30 to 40 flowers per minute. The average number of visited flowers was 19800 to 26 400 flowers per day per head. The effective capacity of A. mellifera to pollinize Russian alfalfa was more than 125 000 heads/hm2 and the maximum seed yield was 1 067.6 kg/hm2.
Control effect of zineb, diffenoconazole and prochlorazmanganese against Stylosanthes anthracnose
2009, 3(8): 152-157.
[Abstract](1624) [PDF 630KB](804)
Stylo anthracnose is one of the main diseases to damage Stylosanthes guianensis, and chemical control is still the most effective method to reduce the damage. The research result showed that the fungal colony growth and conidia germination were inhibited by Zineb (65% WP), Diffenoconazole (50% WP) and ProchlorazManganese (28% WP), in which, the inhibitory rate of colony increased with the concentration of Zineb and Diffenoconazole. After 5 days later, the inhibitory rate reached nearly 100% under the treatment of 3 concentrations of ProchlorazManganese. It reached 95.45% under 700fold diluted Zineb, and 82.13% under 10 000fold diluted Diffenoconazole. The inhibitory rate of conidia germination was positive correlation with the concentration of 3 fungicides and it reached 100% by 700fold diluted Zineb, 10 000fold diluted Diffenoconazole and 1 500fold diluted ProchlorazManganese after treatment for 12 hours. However, the inhibitory rate of conidia germination of Zineb and Diffenoconazole decreased after treatment 36 hours. The relative control effect of 3 fungicides was positive correlated with the concentration, and it was 40.20% by 500fold diluted Zineb, 36.62% by 1 000fold diluted ProchlorazManganese and 22.15% by 7 000fold diluted Diffenoconazole after treatment for 7 days. The relative control effect of fungicide in laboratory test was obviously less than that in pot experiment.
Study of biological characteristics and biocontrol of the brown patch of turfgrass in Tianjin
2009, 3(8): 158-162.
[Abstract](1743) [PDF 827KB](786)
The purified strain RH2 (Rhizoctonia solani) separated from the turfgrass was used to test the features including the suitable temperature, pH and carbon source in Tianjin. In order to resolve the problem caused by the chemical pesticide usage, 7 biocontrol preparations were used to screen the suitable ones. The result showed that suitable culture temperature was 30 ℃ and suitable pH was 6.5 to 7.5, suitable carbon source was sugar, soluble starch or lactose. Nisuo and Telike were the best biocontrol preparations through laboratory screening. The results of pot experiment showed that the control efficiency of Nisuo and Telike were 72.51% and 76.94% when the concentration was 1 500 times and 600 times respectively.
Asexual reproductive characteristics of wild Dichnondra repens in Southwest China
2009, 3(8): 163-171.
[Abstract](1613) [PDF 1802KB](697)
The temporal dynamics, patterns and space configuration of the asexual components of wild Dichondra repens (SD200310, SD200411, GD200504 and SD200304) were studied. The results indicated that 1) main stem growth rate declined over the time, the space expansion depended on the contribution of source strain, early ramets and leaves; 2) the variation of energy demand from plant migration growth and stem/leaf expansion resulted in the differences of clonal growth pattern and the distribution of biomass components in space and configuration; 3) the best density for transplant was 40 cm 40 cm with 5 cm 5 cm sward and main stalk (22.33 cm), leaf number (28.38), node number(24.76)and length of node segment(1.42 cm)were the highest; 4) with the increase of density, spacer length and branching intensity decreased, while the ramify angle increased.
Effect of paclobutrazal on the salt tolerance of Festuca arundinacea
2009, 3(8): 172-176.
[Abstract](1851) [PDF 0KB](436)
The pot experiment was conducted to study the effect of paclobutrazal with different concentrations (200、400和600 mg/L) on the salt tolerance of Festuca arundinacea treated with 0.8% of NaCl. The results showed that the salt stress reduced the root length, dry matter biomass and relative water content in leaf, and increased the MDA content. However, the application of paclobutrazal after salt treatment could increase the dry matter biomass, root length and soluble sugar content. In addition, the paclobutrazal treatment decreased MDA accumulation in leaf. All the benefit from paclobutrazal application could be explained as the release of the salt stress in some extent. The concentration of 400 mg/L of paclobutrazal was the best.
Turf performance of six perennial ryegrass varieties used for overseeding
2009, 3(8): 172-176.
[Abstract](2113) [PDF 0KB](624)
The turf characters of 6 varieties of perennial ryegrass, including the speed of seedling emergence, tiller density, texture and turfgrass quality was studied to evaluate their suitability under field conditions in Nanjing. The results showed that 6 varieties performed well in seedling emergence and turf establishment and better adaptability and turf performance during the spring and autumn. Tiller density, turf quality, texture and regeneration speed of the tested varieties declined under the stress of heat in summer, in which, the turf characters of Ignite and Regal 5 were better than other varieties and could be used for overseeding in Nanjing and other regions with the same climate.
Study on light utilization characteristics and LAI response to soil nutriments of Ficus tikoua
2009, 3(8): 181-186.
[Abstract](1378) [PDF 0KB](395)
The light utilization characteristics and LAI response to soil nutriments of Ficus tikoua were studied. The results indicated that 1) the light saturation point (LSP) and light compensation point (LCP) were 1 124 and 0 mol/(m2s) respectively, which implied that it could grow in a wide light condition; 2) the water use efficiency (WUE) ranged from 1.45 to 15.8 and reached the maximum value while PAR reached 500 mol/(m2s), this suggested that it could consume less water in daily management; 3) the mean LAI was 1.507 (ranged from 0.664 5 to 2.671 7), which was lower than that of other ground cover species; 4) LAI was sensitive to soil water and nitrogen content, but not sensitive to soil organic C, P and K.
Effects of NaCl stress on some physiological characteristics of white clover
2009, 3(8): 187-189.
[Abstract](1487) [PDF 0KB](423)
The seedling of Trifolium repens was treated with different concentrations of NaCl. The dynamics of chlorophyll a (Cha), chlorophyll b (Chb) and total contents of chlorophyll (Chl) and cell membrane permeability in response to salt stress were studied. The results showed that the contents of Cha, Chb, Chl and the relative conductivity increased at first and then decreased when NaCl concentration increased or salt stress was prolonged. The contents of Cha, Chb and Chl increased when NaCl concentration was below 150 mmol/L, and then they decreased along with the increase of NaCl concentration. The relative conductivity reached the maximun at 200 mmol/L of NaCl concentration.
Effect of irrigation methods on seedling emergence of Galega orientalis cv. Xinyin No.1
2009, 3(8): 190-190.
[Abstract](1326) [PDF 0KB](453)
Irrigated agriculture was an inevitable choice for the agriculture and animal husbandry in the arid and semiarid areas of the north slope of Tianshan Mountains. The effects of flooding irrigation, flooding irrigation + microspray irrigation and microspray irrigation on seedling emergence of Galega orientalis cv. Xinyin No.1 were studied. The results showed microspray irrigation was the best. The flooding irrigation + microspray irrigation was better and the seedling emergence rate was increased by 92% compared with flooding irrigation.