• Volume 36,Issue 1,2015 Table of Contents
    Select All
    Display Type: |
    • Effects of different selenium sources on production performance,thyroid level and immune function in sows during lactation

      2015, 36(1):1-8. DOI: 10.7671/j.issn.1001-411X.2015.01.001

      Abstract (1843) HTML (471) PDF 966.06 K (1865) Comment (0) Favorites

      Abstract:【Objective】This experiment was conducted to study the effects of different Se sources on production performance,thyroid level and immune function in sows during lactation.【Method】A total of 200 LY(Landrace×Yorkshire)binary hybrid multiparous sows(healthy,with similar body condition,close due date,3-6 parities)were allotted to 10 groups randomly,with 20 replications in each group. Group one was the control group fed with basal diet without supplementation of Se. The other 9 groups were supplemented with 0.3,0.5 or 0.7 mg·kg-1 Se-containing sodium selenite,yeast selenium or nano-selenium respectively. The whole feeding experiment lasted for 58 days.【Result and conclusion】The birth mass of group supplemented with yeast selenium by 0.3,0.5 mg·kg-1 or nano-selenium by 0.5,0.7 mg·kg-1 was significantly higher than that of the control group(P<0.05).The group with 0.5 mg·kg-1 selenium yeast was significantly higher than those of the control group and the group with sodium selenite in mass of weaning litter,litter mass gain and daily gain(P<0.05).The effect of different sources of selenium on 3,3′,5-triiodothyronine(T3)and 3,5,3′,5′-thyroxine(T4)mass concentrations in serum of lactation sows and sucking piglets was extremely significant (P<0.01).Compared with the control group,groups with sodium selenite or selenium yeast,the serum T3 mass concentration of sows fed on the diets supplemented with nano-selenium group significantly(P<0.01)increased by 29.52%,17.24% or 23.63%,respectively,but the serum T4 mass concentration significantly(P<0.01)decreased by 24.71%,30.88% or 33.86% respectively. Compared with the group with sodium selenite or selenium yeast,the serum IgA and IgM mass concentration of sows fed on the diets with nano-selenium increased by 85.39% and 79.35%(P<0.01)or 24.19% and 50.98%(P<0.01)respectively. Compared with the control group,the serum IgG mass concentration of sucking piglets from the sows fed on the diets with sodium selenite, nano-selenium or selenium yeast significantly(P<0.01)increased by 19.11%,43.39% or 34.63% respectively,while the serum IgA and IgM mass concentration increased by 93.67%,160.75% or 132.91% and 90.91%,140.91%or 102.27% respectively.The results indicate that nano-selenium or selenium yeast supplemented in diets can significantly improve the reproductive performance and immune function of sows,and regulating the secretion of thyroxine.

    • Degradation-elimination rules and influences on aquatic ecosystems of arsenilic acid in simulating pond

      2015, 36(1):9-13. DOI: 10.7671/j.issn.1001-411X.2015.01.002

      Abstract (1536) HTML (553) PDF 808.47 K (1655) Comment (0) Favorites

      Abstract:【Objective】In this paper, by simulating the pond water ecosystem, degradation rule in water and sediment and the impact on aquatic ecosystem of arsanilic acid were studied.【Method】Four mini-aquatic pond ecosystems were established; the control was added 100 g pig manure and treated with different mass concentrations of 50, 150 and 500 mg/L of arsanilic acid. Samples of water and 2 cm-depth-sediment were taken. Arsanilic acid was determined by HPLC and the total arsenic contents were determined by HG-AFS.【Result and conclusion】The half-life of arsanilic acid increased with the extension of the delivery drug concentration in pond water and surface sediment, which was 3.73 to 16.04 d and 35.17 to 61.27 d, respectively, and the total arsenic showed a distinguished subsidence trend in sediment and degraded slowly. The values of dissolved oxygen(DO), pH, primary productivity(P/R), activities of sediment alkaline phosphatase and catalase, and the content of total nitrogen and phosphorus indicators were regularly detected. The results showed that 500, and 150 mg/L arsanilic acid could cause irreversibly detectable effects on the ponds. High mass concentration of arsanilic acid obviously inhibited catalase activities. The total nitrogen content of sediment showed an inhibition-promotion-change process, and all mass concentrations of the total phosphorus content declined and presented a concentration dependent relationship.

    • An acute toxicity test of compound traditional Chinese medicine “Huhezi” and its efficacy in chickens experimentally infected with Salmonella pullorum

      2015, 36(1):14-17. DOI: 10.7671/j.issn.1001-411X.2015.01.003

      Abstract (1687) HTML (636) PDF 676.89 K (1578) Comment (0) Favorites

      Abstract:【Objective】To investigate the toxicity of compound traditional Chinese medicine “Huhezi” and observe its efficacy in chickens experimentally infected with Salmonella pullorum. 【Methods】According to the veterinary drug research technical guidelines,the acute toxicity test was carried out in mice by gavage with “Huhezi”extracts. To evaluate the efficacy of “Huhezi” granules,the chickens experimentally infected with Salmonella pullorum were treated at a dosage of 4.20,1.62,0.48 g/d respectively by drinking water for 7 successive days.【Result and conclusion】The dose of acute toxicity test of “Huhezi”extracts was over 5 000 mg/kg. No death was observed in mice,revealing LD50> 5 000 mg/kg. The maximum tolerated dose was 40 g/kg. The cure rates of different dose granules groups were 75.0%,72.7%,62.5% and the effective rates were 83.3%,81.8%,75.0% respectively, while the mortality rate of infected control group was 40%. The result of χ2 test showed that the mortality rate of high and medium dose group of “Huhezi” granule was significanty different from that of the infected control group. The results indicate that compound traditional Chinese medicine extracts are non-toxic, and the high and medium dose of “Huhezi” granules have certain protection to infected death of S. pullorum, with cure rates and effective rates of high dose group being higher than that of medium and low dose groups, the mortality rates of high and medium dose groups being lower than that of the infected control groups.

    • Expressions and antiviral bioactivities of chicken interferon α/ chicken interleukin-18 fusion protein

      2015, 36(1):18-22. DOI: 10.7671/j.issn.1001-411X.2015.01.004

      Abstract (1741) HTML (348) PDF 1.25 M (1506) Comment (0) Favorites

      Abstract:【Objective】This study was conducted to explore a highly efficient chicken gene engineering antiviral agent to prevent and control the chicken viral disease. A recombinant plasmid pET28a-rChIFNα-IL18 was constructed,which was expressed in Escherichia coli, purified by Ni-NTA and tested for antiviral bioactivitiy. 【Method】 This study introduced a novel method for constructing vectors by fusion PCR, which generated PCR products with overlapping chain using Primers complementary to the end. Through the extension of PCR products, ChIFN-α and ChIL-18 constituted the ChIFN-α-ChIL-18 fusion gene when cloned into the vector pET-28a, induced the expression in E. coli strain BL21(DE3). This protein was purified by Ni-NTA and detected by SDS-P AGE and Western-blot. Cytopathic effects(CPE)were applied to examine the potency of recombination rChIFN-α-ChIL-18 against vesicular stomatitis virus(VSV)and newcastle disease virus(NDV)proliferation.【Result and conclusion】 The fusion gene of ChIFN-α-ChIL-18 was successfully constructed and cloned into pET-28a vector. The rChIFN-α-ChIL-18 protein was expressed in E. coli and successfully purified with a molecular mass of about 38 000 and more than 90% on SDS-PAGE,which indicated that the correct rChIFN-α-ChIL-18 fusion protein had been obtained.The antiviral activity units of rChIFN-α-ChIL-18 protein inhibiting the reproduction of VSV and NDV on chicken embryo fibroblast(CEF) cells were much higher than those of the recombinant rChIFN-α,rChIL-18 protein.

    • A study on the histology of digestive system in early life stages of Oplegnathus fasciantus

      2015, 36(1):23-27. DOI: 10.7671/j.issn.1001-411X.2015.01.005

      Abstract (1416) HTML (474) PDF 3.28 M (1526) Comment (0) Favorites

      Abstract:【Objective】The histology of digestive system in early life stages of Oplegnathus fasciantus was investigated. 【Method】 By using continual section cutting technique, morphological changes and histological characters from newly hatched larvae to 35 days after hatching were described. 【Result and conclusion】 Under the conditions of water temperature 24-27 ℃, salinity 29-30 and pH 7.4-8.2, the digestive tract of newly hatched larvae was only an undifferentiated simple closed tube above the posterior segment of yolk-sac with larger volume and color in reddish by H-E staining. Digestive system of O. fasciatus developed their morphology and function further with growth; it can be divided three stages: digestive tract hardly differentiated at the first stage from 0 to 3 days after hatching. At the second stage from 4 to 18 days after hatching, the digestive system was brought to primarily perfect, functioning as feeding, digestion and assimilation. At the third stage from 19-35 days after hatching, gastric glands and pyloric caeca were formed and development of digestive system became perfect and similar to that of the adult fish.

    • Effects of special fertilizer for aromatic rice on characteristics of photosynthesis and matter production of aromatic rice

      2015, 36(1):28-32. DOI: 10.7671/j.issn.1001-411X.2015.01.006

      Abstract (2088) HTML (231) PDF 683.39 K (1619) Comment (0) Favorites

      Abstract:【Objective】To investigate the effects of special fertilizer for aromatic rice on characteristics of photosynthesis and matter production of aromatic rice. 【Method】A field contrast experiment was conducted with four conventional aromatic rice cultivars, Guixiangzhan, Nongxiang 18, Xiangyaxiangzhan and Meixiangzhan, to evaluate the effects of special fertilizer for aromatic rice (SF) and conventional fertilizer (CK) on relative chlorophyll content (SPAD), leaf area index (LAI), net photosynthetic rate, photosynthetic potential, crop growth rate, dry matter accumulation of population, harvest index and grain yield.【Result and conclusion】The results showed that compared with CK, special fertilizer for aromatic rice could significantly increase SPAD, LAI, net photosynthetic rate and crop growth rate of four aromatic rice cultivars at the later growth stage. SF could generally improve harvest index and grain yield,including a significant yield increase of Guixiangzhan, Xiangyaxiangzhan and Meixiangzhan, an increase of 16.46%-22.33%. The capacity of photosynthesis and matter production of aromatic rice cultivars at the later growth stages under SF have obvious advantages, and SF promotes the matter production and accumulation. Therefore, the grain yield increases.

    • Comparation on lodging-resistance characters of soybean in different population structures

      2015, 36(1):33-41. DOI: 10.7671/j.issn.1001-411X.2015.01.007

      Abstract (1720) HTML (370) PDF 1.02 M (1686) Comment (0) Favorites

      Abstract:【Objective】To solve the problem of lodging with density increase in the soybean production improving process and the soybean lodging-resistance characters in different population structures. 【Method】Five levels of planting densities were designed to study the lodging-resistance mechanisms of stem and root selecting the new soybean varieties of Jinong30 and Jinong40 as the tested materials. 【Result and conclusion】Density could change the inner structure of plant population. With the population density increasing, lodging aggravated gradually and the difference was significant compared with the low density. In the high density population structure, the internode length became obviously long compared with the low density; the fresh mass unit stem length of basal internodes was lower than that of upper internodes, and low density was opposite. With the density increasing, the decreasing range of basal stem diameter and fresh mass was more obvious than that of upper internodes. The matter distribution of stem basal from the first to the fifth internodes was changed, which weakened the lodging resistance of the plant. The stem lodging-resistance characters were as follows: with the plant density increasing, the stem crushing strength, stem lodging-resistant index and fresh mass unit stem length decreased significantly; there were significantly negative correlations between all above indexes and lodging; the plant height/stem diameter, height of gravity center, internode length/diameter increased significantly, and there were significant positive correlations. The root nodule number, root dry mass and bleeding amount of soybeans decreased with the density increasing, and there were negative correlations, the correlations between lodging series and bleeding amount and root dry mass reached an extremely significant level with the highest correlation coefficients. The experiment showed that the above-ground stem crushing strength, tem lodging-resistant index, the root bleeding amount and root dry mass most closely correlated with lodging, which was feasible to measure the plant lodging-resistance capacity. Moreover, the soybean plant had a certain self-recovering capability under mild and moderate lodging conditions.

    • An analysis of the contents of aroma components in flue-cured tobacco in Zhaotong tobacco-growing areas

      2015, 36(1):42-47. DOI: 10.7671/j.issn.1001-411X.2015.01.008

      Abstract (1577) HTML (604) PDF 723.63 K (1483) Comment (0) Favorites

      Abstract:【Objective】To understand the contents of aroma components in flue-cured tobacco in different tobacco-growing areas of Zhaotong. 【Method】The central flue-cured tobacco leaves of 120 samples were collected from 8 tobacco-growing areas of Zhaotong. The aroma components of these samples were detected. These indexes were analyzed using multiple comparisons and cluster analysis. 【Result and conclusion】At 0.05 level, there were no significant difference among 13 aroma components of samples, but there were significant differences among 56 aroma components of samples. Based on the functional groups aroma components, there were significant differences of aldehydes, alcohols, phenols, heterocyclic, esters, acids, olefins aroma contents of these samples except for ketene aroma content. Based on the functional groups of aroma components, the results of cluster analysis indicated that 8 tobacco tobacco-growing areas of Zhaotong could be classified into 4 types: The first type included Daguan, Yiliang and Zhenxiong areas; the second type included Qiaojia and Weixin areas; the third type included Ludian and Zhaoyang areas; the fourth type included Yongshan area. The contents of aroma components of samples in different tobacco-growing areas of Zhaotong were different, 81.16% of the aroma components of these samples were significantly different. When evaluating the content of aroma component in flue-cured tobacco of Zhaotong areas, not only the total aroma components in flue-cured tobacco but also the composition and proportion should be taken into consideration.

    • Effects of paddy-upland rotation on control of Pomacea canaliculata and rice yield

      2015, 36(1):48-53. DOI: 10.7671/j.issn.1001-411X.2015.01.009

      Abstract (2244) HTML (452) PDF 987.50 K (1657) Comment (0) Favorites

      Abstract:【Objective】To investigate the influence of paddy-upland rotation on controlling Pomacea canaliculata and rice yield. 【Method】 Four farming measures including winter potato rotation system, winter ryegrass rotation system, and two winter fallow rice fields treatments with water cover or without any water cover (two controls) were employed. The field population structure of snails in the previous and subsequent rice field, and early rice yield in the subsequent season were investigated.【Result and conclusion】 The results showed that winter potato rotation treatment was helpful for snails control and rice yield increase in the subsequent farming season, but the snail population recovery accelerated in the early rice growing period because of this rotation treatment. Winter ryegrass rotation treatment was unsatisfactory for snails control while it was beneficial for the early rice output of the next season. Winter-planting rotation was negative for controlling snail eggs, while the eggs were relatively few and most of them were distributed on weeds along field ridges. The eggs could be collected conveniently and efficiently at the beginning of the early rice growing season.

    • An comparative study on functional diversity of soil microbial community in vegetable garden soils from different regions of Guangdong Province

      2015, 36(1):54-59. DOI: 10.7671/j.issn.1001-411X.2015.01.010

      Abstract (1377) HTML (570) PDF 767.38 K (1577) Comment (0) Favorites

      Abstract:【Objective】To understand the characteristics and differences among the carbon catabolic diversities of vegetable garden soil microbes from the different regions of Guangdong Province. 【Method】The community structures of vegetable garden soil microbes in the northern, eastern,western and central regions of Guangdong Province(NR,ER,WR and CR) were analyzed using the Biolog Eco-Plate Method.【Result and conclusion】There were different changing tendencies of the Average Well Color Development (AWCD), Shannon Index, Simpson Index and McIntosh Index in the four regions. The AWCD value, which directly reflected the microbial activities, was in the order of NR>ER>WR>CR, demonstrating the differences among the uses of carbon sources and abundance in vegetable garden soil microbes from the different regions. There were differences among utilization degrees of the 31 types, 6 classes of carbon sources by the vegetable garden soil microbes from the four regions. Through principal component analysis, it showed that the contribution rate of the PC1 of the metabolism substrates of vegetable garden soil microbes in the four regions was 54.76%, PC2 was 13.25%, and there were 22 types of metabolism substrates in PC1 with over 0.18 of load,but only 15 types in PC2.Amino acids, carboxylic acids, phenols and carbohydrates were the four main carbon sources separating the two principal component factors. In conclusion, the carbon source utilization modes and metabolic functions of the microbes among the vegetable garden soils from the four regions differ from each other, that is, there are different functional diversities of microbial community among the vegetable garden soils from the four regions under investigation.

    • Effects of the activator on potassium release from potassium-rich shale and potassium feldspar and its mechanism

      2015, 36(1):60-64. DOI: 10.7671/j.issn.1001-411X.2015.01.011

      Abstract (1679) HTML (281) PDF 701.61 K (1479) Comment (0) Favorites

      Abstract:【Objective】 Comprehensive utilization of water-insoluble potassium resources is helpful to relieve the contradiction between supply and demand of potash market. 【Method】The activated effects and fertilizer effects were studied by water extraction experiment and pot trial. The mechanism of activation was discussed by X-ray diffraction (XRD).【Result and conclusion】 The results of water extraction experiment indicated that, within the QN ratio of 0.1%-10.0%, potassium-rich shale and potassium feldspar had different activated effects. With the increase of QN ratio, the water-soluble K extraction from potassium-rich shale increased and then decreased, and the activated ratio of 1.0% was the best. For potassium feldspar, the water-soluble K accumulative amount increased as the ratio of QN increased, and when the QN ratio was 10.0%, the accumulation of water-soluble K was the highest. The pot trail results showed that the pot biomass of activated K-shale was 49.42% higher than that of K-shale, reaching the potassium chloride level. For activated K-feldspar, the corn biomass was not significantly different from K-feldspar, which was lower than that of K-chloride and activated K-shale. The results of XRD analysis indicated that, the mechanism of QN activated potassium-rich shale and potassium feldspar was an ion exchange reaction between Na+ and K+. Some new sodium minerals can be found in activated K-shale and activated K-feldspar. In activated K-shale, the new sodium minerals include K0.96Na0.04AlSi3O8, Na4Al2Si6O17·2H2O and Na6PbO4, but it is Na3Mn(PO4)(CO3) in activated K-feldspar.

    • Hybridization of ‘Zaozhong No.6’ and big-fruit Spanish loquat cultivars and fruit evaluation of the hybrids

      2015, 36(1):65-70. DOI: 10.7671/j.issn.1001-411X.2015.01.012

      Abstract (1574) HTML (441) PDF 1.18 M (2246) Comment (0) Favorites

      Abstract:【Objective】To breed new loquat cultivars with big fruit sizes and high quality characteristics, which were adaptive to the local ecological environment and welcome by consumers in Guangdong. 【Method】In this study, the hybridization breeding of loquat between different cultivars was carried out. The domestic excellent loquat cultivar ‘Zaozhong No.6’ and four big-fruit Spanish loquat cultivars (‘Javierin’, ‘Peluches’, ‘Marc’ and ‘Ullera’) were selected as parents. The quality of the mature fruit from the orthonogal group offspring lines was analyzed or evaluated, including average mass of single fruit, flesh color, total soluble solids(TSS), sugar, acidity, seed number etc..【Result and conclusion】From the hybridizations, 15 offspring lines had been preliminarily selected as good progenies, as TSS of them were higher than those of ‘Zaozhong No.6’, and the average mass of single fruit was greater than that of ‘Zaozhong No.6’. Some lines possessed higher sugar/acid ratios than those of ‘Zaozhong No.6’. Three of the hybrids were selected and named ZJ14, ZJ191 and ZM24. The results showed that the separation of the average mass of single fruit and the TSS were extensive. The average mass of single fruit showed a trend of gradual decrease, with only 5.26% of hybrid plants producing big fruits (m>50 g); the TSS showed a trend of gradual increase, and the ratio of the over-parent heterosis plants was over 50%. The flesh color of these hybrids showed mutation, for some hybrids had yellow flesh as their parents did, while the other hybrids produced white flesh fruits. There was an obvious deviation between fruit size (the average mass of single fruit) and the flavor quality TSS. The progeny lines inherited the traits of high-sugar and high-acidity from their parents. New cultivars with high sugar and acid will probably be selected in the future.

    • Studies on the relationship between feeding sites and bacterium acquisition efficiency of Diaphorina citri on Huanglongbing-infected citrus

      2015, 36(1):71-74. DOI: 10.7671/j.issn.1001-411X.2015.01.013

      Abstract (1789) HTML (430) PDF 605.62 K (1673) Comment (0) Favorites

      Abstract:【Objective】To clarify the best feeding sites and the shortest time of Diaphorina citri Kuwayama in spreading Huanglongbing(HLB)and to provide guidance for the prevention and control of HLB.【Method】The bacterium acquisition efficiency of D. citri was tested by PCR, which had been fed on three different parts: tender shoots, mature leaves and old leaves of infected Citrus reticulata Blanco. cv. Mashuiju and Citrus sunki Hort. ex Tanaka for 24 h. 【Result and conclusion】The results showed that the infected rates of D. citri were significantly different among the three parts of C. reticulate. The infected rate on mature leaves was the highest and old leaves was the lowest. The bacterium acquisition efficiencies were also different among the three parts of C. sunki. The infected rates of old and mature leaves were both significantly higher than those of tender shoots. There was no significant difference between the old and mature leaves. The bacterium acquisition efficiency of D. citri feeding on tender shoots of C. reticulate was significantly higher than that on C. sunki, while on old leaves of C. sunki were significantly higher than that on C. reticulate, and there was no significant difference between the 2 species when feeding on mature leaves. The two hosts had the same infected rate of 36.67% when compared feeding on the whole plants.

    • Establishment and optimization of SRAP-PCR system in Canavalia ensiformis

      2015, 36(1):75-78. DOI: 10.7671/j.issn.1001-411X.2015.01.014

      Abstract (1592) HTML (488) PDF 1.16 M (1786) Comment (0) Favorites

      Abstract:【Objective】The purpose of this study is to establish the SRAP-PCR reaction system for Canavalia ensiformis. 【Method】An optimization experiment with single factor design was conducted, comprising five factors of Taq DNA polymerase, Mg2+, primer, dNTPs and DNA template, each with eight concentration levels,aiming to screen their suitable concentration range. After that, uniform design U16(45)and U12(35) were operated in order to improve the accuracy. 【Result and conclusion】The results showed that the optimum SRAP-PCR system was established, including Mg22+ 1.75 mmol/L, dNTPs 200 μmol/L,primers 0.36 μmol/L, Taq DNA polymerase 0.06 U/μL and DNA template 40 ng in the 25 μL reaction system. The reaction system is steady and dependable, which can be applied to the analysis of Canavalia ensiformis by SRAP.

    • Seedling growth,morphology and physiological characteristics of Triadica rotundifolia and Croton lachnocarpus under drought stress

      2015, 36(1):79-84. DOI: 10.7671/j.issn.1001-411X.2015.01.015

      Abstract (1334) HTML (366) PDF 1.65 M (1544) Comment (0) Favorites

      Abstract:【Objective】Seedling growth, morphology and physiological characteristics of Triadica rotundifolia and Croton lachnocarpus were investigated under drought stress to provide scientific basis for species selection and artificial reforestation in the limestone region of South China. 【Method】Pot culture experiment was applied in this study to simulate drought stress by watering frequency.The physiological indicators were measured with comventional methods.【Result and conclusion】The results showed that height growth of T.rotundifolia and C. lachnocarpus declined by 2%-5% and 8%-10% respectivly, while basal diameter growth increased by 17%-35% and 10%-30% respectivly under drought stress. Seedling aboveground biomass, underground biomass, total biomass, and root shoot ratio could be enhanced by light drought stress, but they declined with the increase of drought stress. Results of physiological examination showed that the soluble protein content, peroxidase (POD) activity, activity of superoxide dismutase (SOD), and malondialdehyde (MDA) content varied with species and drought stress. Soluble protein content and POD activity were more sensitive than the activity of SOD and MDA content. Comparison of the stem anatomical structure showed that there were differences in the structure of cortex, phloem, xylem and marrow. Drought would result in increasing ratio of xylem and marrow, which indicated that they could adapt to drought stress by adjusting xylem and marrow structure. Analyses of subordinate functions showed that the drought tolerance of T.rotundifolia were higher than that of C. lachnocarpus under various drought stresses. They may possess different resistance mechanisms to drought stress based on their difference in physiological responses and stem anatomical structures.

    • Effects of drought stress on chlorophyll fluorescence parameters of two fast-growing tree species

      2015, 36(1):85-90. DOI: 10.7671/j.issn.1001-411X.2015.01.016

      Abstract (1710) HTML (307) PDF 803.92 K (1584) Comment (0) Favorites

      Abstract:【Objective】A comparison of drought resistance was made between two fast growing species in South China, Eucalyptus urophylla× E. grandis(EE for abbr.) and bamboo willow (BW for abbr.).【Method】Effective quantum yield of PSⅡ photochemistry(Yield), apparent electron transport rate(ETR), the photochemical quenching (qP ), the non-photochemical quenching (qN), minimal fluorescence(F0), maximal fluorescence(Fm), potential photochemical efficiency of PSⅡ(Fv/Fm) in EE and BW were tested by OS5P pulse modulated chlorophyll fluorometer under drought stress. 【Result and conclusion】 Yield, ETR, qP, Fm and Fv/Fm all declined during the drought. At day 24 after treatment, ETR declined by 48.02% and 25.12% EE and BW, respectively. qN and F0 in the 2 species increased. qN in BW rose by 217.59%, which was significantly higher than that in EE (146.40%, P<0.05). The relative increment in F0 in BW (49.11%) was smaller than that in EE (92.03%) at the end of the drought treatment. Correlation analyses were made concerning chlorophyll fluorescence characteristics and soil water content. In both species, ETR showed a significant positive correlation with soil water content (P<0.01). F0 in EE showed a significant negative correlation with soil water content (P<0.01). Fm and Fv/Fm of BB and soil water content showed a significant positive correlation (P<0.01). These results indicate that correlations existe among chlorophyll fluorescence characteristics in two species under drought. BW has greater drought resistance than EE as revealed by chlorophyll fluorescence characteristics.

    • Effects of ozone and drought on fluorescence physiology of seedlings of three afforestation tree species in South China

      2015, 36(1):91-95. DOI: 10.7671/j.issn.1001-411X.2015.01.017

      Abstract (1381) HTML (250) PDF 735.67 K (1454) Comment (0) Favorites

      Abstract:【Objective】This study was conducted to demonstrate the fluorescent physiology of ozone resistance and drought physiology mechanism in the seedlings of three native tree species and provide reference for screening stress-resistant tree species in South China. 【Method】Seedlings of Elaeocarpus apiculatusMytilaria laosensis and Castanopsis fissa were treated with ozone fumigation and drought condition, and their chlorophyll fluorescence parameters were determined.【Result and conclusion】 The results showed that with increasing treatment time, minimal initial fluorescence (F0) of the three seedling types increased and then decreased, and their PSⅡ maximum photochemical efficiency (Fv/Fm) remained stable; active quantum efficiency of PSⅡ[Y(Ⅱ)] treated with ozone stress decreased, followed by an increase and other treatments remained stable; non-photochemical quenching (NPQ) of E. apiculatus seedlings remained stable and other seedling types increased and then decreased. Principal component analyses showed that resistance of the three seedling types to ozone stress and drought stress was C. fissa > E. apiculatus > M. laosensis, whereas their resistance to intercross stress of ozone and drought was E. apiculatus > C. fissa > M. laosensis. In general, the three seedling types have a certain ability to resist ozone or drought by starting an adjustment mechanism of photoprotection under ozone stress or drought stress.

    • Design and experiment of the 2BQHM-2 peanut mulching film and punching planter

      2015, 36(1):96-100. DOI: 10.7671/j.issn.1001-411X.2015.01.018

      Abstract (1815) HTML (541) PDF 1.23 M (1640) Comment (0) Favorites

      Abstract:【Objective】To preferably accomplish the operation process of punching hole and planting.【Method】The 2BQHM-2 air-suction peanut mulching film and punching planter was designed and manufactured for technical issues and requirements of peanut mulching film and punching planter. Based on theoretical analysis of the working parameters of the key parts, parts’ structural optimal design of the planter components were completed with UGNX. With the virtual prototype technology, the machine was virtual assembled, and the cavitations’ process of motion simulation was analyzed. The rationality and usability of machine components were tested.【Result and conclusion】 In the peanut growing typical region, the planter field trial showed that overall performance was relatively stable, with each component operated smoothly, and the operating indicators could meet the technical requirements better. Test results of the virtual simulation were basically consistent with the operational effects of the planter. The study has provides a theoretical basis and technical reference for further optimization design of the mulching film and punching planter.

    • Researchs of the relationship between compression ration and axial stress of castor seeds of different states in different squeeze ways

      2015, 36(1):101-105. DOI: 10.7671/j.issn.1001-411X.2015.01.019

      Abstract (1293) HTML (334) PDF 1.12 M (1405) Comment (0) Favorites

      Abstract:【Objective】To study the relationship of compression ratio between axial stress and castor seeds in different states with different squeeze methods. 【Method】Cold pressing tests of complete and crushed castor seeds were accomplished in different squeeze ways with different squeeze rates. Hyperbolic compression relationship model between ratio and stress was developed on the basis of the Kawakita’s equations. The parameters of the model were determined by the least square method according to the tested results.【Result and conclusion】 The results showed that crushed castor seeds achieved an equivalent compression ratio consistent with complete ones, while the actual compression ratio was much smaller than that of the complete seeds. Pressing repeatedly under the same conditions can achieve a greater compression ratio than that of a single press. Simulated values and measured values matched well by comparison of values and their error analysis.

    • A comparative analysis of AVHRR, SPOT-VGT and MODIS NDVI remote sensing data over Hanjiang River basin

      2015, 36(1):106-112. DOI: 10.7671/j.issn.1001-411X.2015.01.020

      Abstract (1933) HTML (809) PDF 2.82 M (1856) Comment (0) Favorites

      Abstract:【Objective】To select an optimum time series in remote sensing data for evaluating land cover changes and their impacts on southern China. 【Method】 Three types of remote sensing NDVI data from AVHRR, SPOT-VGT and MODIS were analysed to compare their similarities and differences in different vegetation types over Hanjiang River basin from 2001 to 2006, and their correlations were analysed using linear regression method. 【Result and conclusion】 These data had generally similar distribution patterns in space. MODIS and SPOT-VGT NDVI matched well. MODIS could recognize objects more clearly on the earth surface due to its spectrally narrow sensors with high spatial resolution. In MODIS NDVI, values varied within a wide range, therefore more vegetation types could be detected. Three types of NDVI changed seasonally similar to the same amplitude. MODIS NDVI reflected vegetations seasonally change more accurately. In AVHRR NDVI, some vegetation types change did not match with the actual situation. Although different vegetation types seasonally changed in the same way in three types of NDVI, changes in a more temporally identical pace could be found in MODIS NDVI and SPOT-VGT NDVI compared with AVHRR NDVI. MODIS NDVI could distinguish seasonal changes of croplands, closed shrublands and savannas from other vegetation types. It showed that MODIS NDVI had a higher resolution on reflecting vegetation types and their development compared to SPOT-VGT NDVI and AVHRR NDVI. Throughout the whole basin and on a variety of vegetation types, there were some linear relationships among three NDVIs, while the linear relationship between MODIS NDVI and SPOT-VGT NDVI was the strongest. Based on the linear regression of MODIS NDVI and AVHRR NDVI, MODIS NDVI was estimated accurately consistent with the measured values of NDVI of Hanjiang River basin in 2000. MODIS NDVI time series can provide developing ideas of the historical years.

    • Antimicrobial resistance and pulse field gel electrophoresis analyses of Salmonella Senftenberg from food of animal origins in Shanghai, China

      2015, 36(1):113-116. DOI: 10.7671/j.issn.1001-411X.2015.01.021

      Abstract (2123) HTML (501) PDF 924.63 K (1434) Comment (0) Favorites

      Abstract:【Objective】To investigate the antimicrobial resistance and molecular types of Salmonella Senftenberg isolates from food of animal origins in Shanghai. 【Method】A total of 15 Salmonella Senftenberg isolates were collected from 2008 to 2012 in Shanghai.Agar dilution method and pulse field gel electrophoresis (PFGE) were applied to the determination of minimum inhibitory concentrations (MICs) and molecular typing, respectively. 【Result and conclusion】The 15 isolates exhibited resistance most often to sulfisoxazole(46.7%)and they were fully sensitive to the remaining antibiotics expect for one which was resistant to streptomycin (6.67%). PFGE analyses of 15 Salmonella Senftenberg isolates resulted in 10 unique patterns, among which three (X3, X4, X5) were grouped together at a high similarity index of 88.2%, su-ggesting that these isolates of different origins may be relevant in the epidemiology.