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01 March 2012, Volume 1 Issue 6
    

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  • Research Progress on Fusarium Wilt of Brassica oleracea
    PU Zi-jing1，2，ZHANG Yan-ju1*，LIU Dong1，DAI Li-ting1，WANG Wen-bo1
    . 2012, 1(6): 1-7.
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Fusarium wilt of Brassica oleracea is a soil-borne disease caused by Fusairum oxysporum f. sp. conglutinans．It can be observed in the B. oleracea production regions around the world．It is now an important disease that could reduce quality and production of B. oleracea since 2001，when it was first reported in China．In this study，a review for Fusarium wilt in B. oleracea was made from pathogen，host-resistance and control methods，respectively．Besides，a prospect of future research was prospected.
  • Research Progress on Eggplant Parthenocarpy
    LI Xiang-jing，LIU Fu-zhong*，ZHANG Ying，LI Yan-wei，CHEN Yu-hui，LIAN Yong
    . 2012, 1(6): 8-14.
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    Eggplant（Solanum melongena L.）parthenocarpy can overcome the problem of low temperature，increase production，reduce production cost and improve fruit quality in anti-season cultivation．This paper mainly expounded the research progress on eggplant parthenocarpy from characteristic identification，physiology basis，genetic mechanism and biological studies．It also pointed out the existing problems and research direction in the future．
  • Research Progress on Garlic Leaf Blight and Its Control Method
    CHANG Yan-xia，CHEN Shu-xia*，CHENG Zhi-hui，DU Jun-na，LI Xiao-min，ZHOU Jing
    . 2012, 1(6): 15-20.
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    Garlic（Allium sativum L.）leaf blight is a fungal disease，which mainly damages garlic leaves and blots．In the initiate stage，the leaves displayed white spots，when they were infected by this kind of fungi．Later on the white spots gradually enlarged．Then the leaves were withered and the plants were unbolting，when it happened seriously．This disease influenced the stable and high yield of garlic，and caused a great economic loss．The occurrence and development of garlic leaf blight，the control methods and existing problems both in China and abroad were systematically expounded，and the future research work was also prospected in this paper.
  • Studies on Inheritance and Stability of Morphological Marker of Orange Leaf Head Chinese Cabbage
    GENG Xin-cui，SHEN Xiang-qun*，HOU Hua，HONG Ya-ting，MA Shi-fang
    . 2012, 1(6): 21-26.
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    Taking the orange leaf head Chinese cabbage〔Brassica campestris L. ssp. pekinensis（Lour）Olsson〕self-line（LH）and the white leaf head Chinese cabbage（91-12）self-line as parents，we studied the hereditary feature of cotyledon color of orange leaf head Chinese cabbage and its stability in environment．The result showed that the cotyledon and leaf head of orange leaf head Chinese cabbage and normal leaf head Chinese cabbage，selfing and back-cross F1 and F1′，were both yellow．The separation ratio of F2 and BC1F1 cotyledon color were 3∶1 and 1∶1（yellow∶orange），respectively．This indicated that cotyledon color of orange leaf head was controlled by a pair of recessive alleles．And the inheritance of cotyledon color，flower color and leaf head color belongs to pleiotropism．In other words，if the cotyledon of a plant was orange，its leaf head and flower were also orange．Under the conditions of the dark or weak light treatment，seed leaves of orange leaf head Chinese cabbage showed orange after they were exposed in the sun for about 2 hours．Furthermore under the low temperature（0-3 ℃）and dark conditions，orange seed leaves of orange leaf head Chinese cabbage were observed more clearly，which were not affected by change of pregermination time（24 hours or 48 hours）．So cotyledon color of orange leaf head Chinese cabbage can be applied as an ideal morphological marker for the breeding of orange head Chinese cabbage．
  • Studies on Anthocyanin Accumulation and Related Gene Expression in Big-head Mustard〔Brassica juncea（L.）Czern. et Coss. var. megarrhiza Tsen et Lee〕Induced by Environmental Stress
    SONG Ming，SUN Zi-jian，TANG Qing-lin，WANG Zhi-min，REN Xue-song
    . 2012, 1(6): 27-34.
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    The aim of this work was to study the impact of environmental stress on big-head mustard〔Brassica juncea（L.）Czern. et Coss. var. megarrhiza Tsen et Lee〕anthocyanins production and the expression of structural genes involved in their biosynthesis such as chalcone isomerase（CHI），dihydroflavonol 4-reductase（DFR）and anthocyanindin synthase（ANS）．The CHI gene，DFR gene and ANS gene were cloned by using homology-based cloning strategy，the complementary cDNA of CHI gene has an open reading frame of 759 bp，the DFR gene is 1 157 bp，and the ANS gene is 1 004 bp．The results of real-time RT-PCR analysis suggested that the amount of anthocyanin and the expression of those structural genes required a period of time to reach the peak．The expression of CHI gene were no significant differences under strong light，low temperature and simulating drought stress．And the expression of DFR gene and ANS gene induced by low temperature and strong light stress were increased with prolonged stress time．The expression of DFR gene and ANS gene induced by low temperature and strong light stress led us to the conclusion that those two genes are important for the regulation of anthocyanin in the big-head mustard．Furthermore，the low temperature and strong light stress might induce different regulation mechanisms in the anthocyanin biosynthesis．
  • Cloning of Coat Protein Gene of Tomato Yellow Leaf Curl Virus Strain from Shouguang Region of Shandong Province and Its Expression in E. coli BL21（DE3）
    QIAO Ning1，LI Mei-qin1*，GUO Bao-tai2，LIU Yong-guang1，PEI Hua-li1，ZHU Xiao-ping3
    . 2012, 1(6): 35-40.
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    The PCR test was carried out on tomato（Lycopersicon esculentum Mill．）leaves which were infected by TYLCV in the greenhouse in Shouguang region of Shandong Province using the prime PA/PB．The results showed the yellow leaf curl disease found in Shouguang was caused by TYLCV．A DNA fragment（770 bp in length）encoding TYLCV coat protein（TYLCV-CP）was amplified and inserted into pEASY-T1 Simple vector．After double digestion with Xho I and EcoR I，the fragment was inserted into vector pET-32a．A 50 kD recombinant protein of TYLCV-CP from isolate of Shouguang highly expressed by IPTG in E. coli BL21（DE3）showed a high antigenic activity．
  • Effects of Glomus mosseae on Asparagus Seedling Growth and Mineral Nutrients Absorption
    SUN Chao1，2，HE Chao-xing1*，YU Xian-chang1，ZHANG Zhi-bin1，LI Yan-su1，YAN Yan1
    . 2012, 1(6): 41-47.
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    Glomus mosseae（GM）is a fungi strain of Arbuscular Mycorrhiza Fungus in genus Glomus of high adaptability to environment with extensive application range．To determine the effects of Glomus mosseae on asparagus（Asparagus officinalis L.）seedling，seedling breeding experiments were conducted in solar greenhouse with inoculation of GM to asparagus seeds during sowing．The influences of two GM strains GM1 and GM2 inoculation on asparagus seedling growth，mineral nutrients absorption and roots mycorrhizal colonization were studied．The results showed that GM inoculation greatly increased the biomass of asparagus seedlings．The mycorrhizal dependency of asparagus roots was high and the mycorrhizal colonization ratio of asparagus root exhibited change tendency of“S”curve．Plants roots inoculated with GM were highly colonized 10 weeks after sowing which significantly increased the root activity and chlorophyll concentration in leaves．GM inoculation promoted the plants to assimilate more mineral nutrients such as P and Mg．So，in asparagus cultivation，GM inoculation is an important technique to cultivate vigorous seedlings，shorten seedling stage，save mineral nutrients and raise nutrient utilization ratio．
  • Genotype Differences of Spatial Distribution between Potato（Solanum tuberosum L.）Root and Leaf and Their Effects on Potato Yield
    ZHENG Xu1，2，DENG Ying-yi3，Iwama Kazuoto2，Jitsuyama Yutaka2
    . 2012, 1(6): 48-52.
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    To test the genotype differences of spatial distribution between potato（Solanum tuberosum L.）root and leaf and their effects on potato yield，genotype‘Genyou No. 1’and‘Genyou No. 4’with heavy dry root weight，drought and lodging resistance，and‘Konafubuki’with high yield，super quality，light dry root weight，and lodging acceptance were used at the maximum stage of shoot growth（MSS）under rain-fed field．The results indicated：① The total root lengths within 0-120 cm depth and within 30-120 cm depth of‘Genyou No. 1’and‘Genyou No. 4’were significantly longer than‘Konafubuki’|② The root systems of‘Genyou No. 1’and‘Genyou No. 4’were mostly distributed in the depth of 30-120 cm，while that of‘Konafubuki’was mainly distributed in the layer of soil tillage（0-30 cm）|③ The leaf area distribution of‘Genyou No. 1’was even，while that of‘Genyou No. 4’was mainly concentrated in the middle and upper layer（40-80 cm），particularly in 60-80 cm（accounting for the total leaf area 41.7%）．Therefore，the light absorption coefficient of‘Genyou No. 1’was significantly lower than those of‘Genyou No. 4’and‘Konafubuki’．Thus，the increased tuber dry matter and tuber growth rate of‘Genyou No. 1’was the largest during the period from MSS to harvest|④ There were significant differences between genotypes in the plant height，main stem diameter and specific root length．The plant height and main stem diameter of‘Genyou No. 1’were the largest and its specific root length was the smallest，while the plant height and main stem diameter of‘Konafubuki’were the smallest，but its specific root length was the largest．
  • Identification Methods for Pakchoi〔Brassica campestris L. ssp. chinensis（L．）Makino var. communis Tsen et Lee〕Water-logging Tolerance
    ZHANG Yong-ji1，2，XU Hai2，ZHANG Hui1，2，CHEN Long-zheng2，SONG Bo2，YUAN Xi-han2*
    . 2012, 1(6): 53-57.
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    8 pakchoi genotypes with different water-logging tolerance were selected and treated under 5 different temperature conditions for high humidity，when their seedling leaves were 6，aiming at studying the identification method for pakchoi water-logging tolerance．Finally the saturated soil moisture，95% of relative air humidity，30 ℃/20 ℃ of day 12 h/night 12 h treatment for seedlings of 6 days were determined as identification condition for differences of pakchoi water-logging tolerance．The chlorosis size and degree of chlorotic leaf blades were taken as the grading index for wet injury，and thus to identify the water-logging tolerance of the variety．
  • SNP-based Molecular Assay for Cucumber Hybrid Seed Purity Iden- tification by Pyrosequencing
    LAN Qing-kuo1，ZHANG Gui-hua2，WANG Yong1*，ZHAO Xin1，ZHU Zhu1，CUI Xing-hua2，GUO Yong-ze1，CHENG Yi1
    . 2012, 1(6): 58-63.
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    For the purpose of testing cucumber（Cucumis sativus L.）hybrid purity，a SNP site was screened by high resolution melting（HRM）from 33 commercial cucumber cultivars，whose polymorphism information（PIC）were 0.401．We established the purity test method based the SNP，which was genotyped by pyrosequencing．The method was applied in purity test of‘Youyi’cucumber cultivar．The result indicated that 90 were pure hybrid seeds，and the purity was 96.7%，which is coincide with the results of CLA0 and SSR．Overall，the method is fit for purity test of cucumber hybrid and the SNP-pyrosequencing test model is suitable for distinctness，uniformity and stability（DUS）analysis．
  • Detection of Bacterial Fruit Blotch in Cucurbita pepo L. Seed and Seed Disinfection
    ZHANG Guo-yu，ZHANG Fan，JIANG Li-gang，ZHAI Wei-bo，LI Hai-zhen*
    . 2012, 1(6): 64-67.
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    PCR technique was used to detect the bacterial fruit blotch infected seed in Cucurbita pepo L.，and the effect of different treatments including the solution of CuSO4，bleaching powder，HCl，peroxyacetic acid，streptomycin，doxycycline，high temperature on seed disinfection were analyzed．The results showed that the disinfecting solution of CuSO4 and bleaching powder were effective in extinguish the bacterial from seeds．0.5% solution of bleaching powder with 5 minutes can effectively disinfect the bacterial seeds．It is not necessary to get rid of the reagents with water after treating in bleaching powder solution，because the reagent does not affect the seed germination rate and germination energy．Higher temperature treatment can not work well in bacterial fruit blotch extinguishing．
  • Procurement of Transgenic Potato with AFP Gene and Preliminary Identification of Its Late Blight Resistance
    REN Yu-xia1，CHEN Ling-na2，3，LIU Gui-zhen2，WANG Qing2，YANG Sheng-niu2，SHI Chun-hong4，LI Ting-ting4，HOU Lu-zhen2，CHEN Ji-feng1*，CHEN Zheng-hua2*
    . 2012, 1(6): 68-73.
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    The aim of the study is to obtain the transgenic potato（Solanum tuberosum L.）lines conferring resistance to late blight．AFP（antifungal protein）gene was introduced into potato susceptible cultivar‘Shepody’via Agrobacterium tumefaciens-mediated transformation，using micro-tuber discs as explants．Four positive plantlets were obtained by PCR assay and the glyphosate selection．The micro-tubers were introduced in the dark and then planted in the field to grow into complete plants for the identification of disease resistance．Using detached leaf assay，4 transgenic plant lines were identified for late blight resistance．The result showed that their disease resistance was higher than the non-transgenic ones．
  • Effect of Rare Earth Element Cerium（Cerium chloride）on Cucumber Resistance to Fusarium Wilt
    ZHOU Bao-li，LI Teng-fei，LI Xing-bao，SONG Yan，WANG Ai-jie，ZHENG Qing-ling
    . 2012, 1(6): 74-78.
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    Cucumber fusarium wilt was used as research target．The impacts of adding different concentrations of rare earth element cerium（Cerium chloride）on cucumbers fusarium wilt incidence，the plants growth conditions and the activities of the enzymes related to defense were discussed by pot cultivation experiment．The results showed that cucumber fusarium wilt incidence and disease index were reduced，the plant growth and development was promoted，and the activities of defense enzymes was increased by applying cerium．As cerium concentration increased，the promoting effect increased at first and then decreased as compared with the control．The best effect was 200 mg?L-1 treatment，each cucumber growth index was significantly higher than that of the control．The chlorophyll content，root system activity and proline content（Pro）were increased 85.91%，60.75%，55.77%，respectively．The activities of peroxidase（POD），polyphenoloxidas（PPO）and phenylalanine ammonia-lyase（PAL）were increased by 49.29%，31.50%，80.00%，respectively then the control．Malondialdehyde（MDA）content declined 61.67% than the control.
  • Studies on Inhibitory Effects of Nano-Cu2O on Phytophthora capcisi and Fusarium oxysporum of Pepper
    YANG Jun-li1，DONG Hui-ze1，LI Yi2，TIAN Xiao-li2，HOU Quan-gang2
    . 2012, 1(6): 79-81.
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    Using the special characteristics of nanometer materials to develop nanoscale germicides is a new area of germicide research and development．To investigate the inhibitory effects of nano-cuprous oxide（Cu2O）on Phytophthora capcisi and Fusarium oxysporum of pepper（Capsicum annuum L.），5 concentrations of nano-Cu2O，i. e．250，500，750，1 000，1 250 mg?kg-1 were prepared and drug-containing medium were used for conducting the toxicity test．The results indicated that under the same concentration，the inhibitory effects of nano-Cu2O on Phytophthora capcisi were better than those on Fusarium oxysporum．The inhibitory effect was positively correlated to concentration，and correlation coefficient was over 0.97．The EC50 was 135.4 mg?kg-1 and 706.2 mg?kg-1 for Phytophthora capcisi and Fusarium oxysporum，respectively．Nano-cuprous oxide had significant effects on pepper Phytophthora capcisi．
  • Evaluation of Control Efficiency on Beichuang Synergist Mixture with Chlorpyrifos against Bradysia odoriphaga Yang et Zhang
    WANG Hong-tao，WANG Pei-song，LUAN Bing-hui，WANG Ying-zi*
    . 2012, 1(6): 82-84.
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    The control efficiency of less Chlorpyrifos than conventional dosage mixed with Beichuang synergist in controlling Bradysia odoriphaga Yang et Zhang was evaluated in the field．The results showed that the control efficiency of the mixture containing 14% of Beichuang synergist and 30%-40% less Chlorpyrifos than conventional dosage in against Bradysia odoriphaga Yang et Zhang was 98.46% to 97.50%．The control efficiency was corresponding to that of 48% Chlorpyrifos conventional dosage．
  • Synergistic Effect of Mixing Kresoxim-methyl with Difenoconazole to Control Sphaerotheca aphanis
    ZHU Wei-gang，HU Wei-qun，ZHANG Rui-rui，CHEN Jie*
    . 2012, 1(6): 85-88.
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    Kresoxim-methyl is one of the new fungicides commonly used for controlling strawberry powdery mildew．In order to select mixture of kresoxim-methyl with difenoconazole of synergistic control effect against strawberry powdery mildew，we screened by pot experiment Sphaerotheca aphanis among fungicide mixtures．The results showed that CTC values of the mixtures with the mixing ratio of Kresoxim-methyl and difenoconazole as 1∶1，1∶3，1∶5，1∶7，1∶9 were 157.91，121.83，116.65，114.07 and 108.08，respectively．The results also showed that the 2 ratios among the 5 as 1∶1 and 1∶3 to Sphaerotheca aphanis had obviously synergistic effect，and the rest 3 had additive effect．Among the 5 matching ratios，1∶1 ratio had the best effect，both from the synergistic effect and the control effect.
  • Inducement and Identification of Yellow Flesh Tetraploid Watermelon
    ZHANG Na，SUN Yu-hong*，DING Ming，ZENG Hong-xia，SHI Xian-feng，REN Jian，LI Yu-hua，DU Nian-hua，TANG Mi
    . 2012, 1(6): 89-92.
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    We induced tetraploid watermelon by treating the seedling growingpoints of yellow flesh diploid watermelon with 0.3% and 0.4% solution of colchicines．Autotetraploid plants were selected and identified on morphology，flow cytometry，hybridization and quality．After 3 successive quarters cultivation and observation，we gained a stable tetraploid．The results showed that the most effective treatment was extirpating interior-leaf at the 8th day after sowing，then treating the seedling growing points with 0.3% colchicine for 6 days．The survival rate of seedlings could reach over 80% and the induction frequency of tetraploid watermelon could be stabled above 16%．The treatment can improve the accuracy of selection high-quality tetraploid material combined with other identification methods．
  • Initial Exploration about Creation of New Tomato Male Sterile Line and Its Seed Production Technology
    ZHANG He，LI Jing-fu，ZHUANG Lei，XU Xiang-yang*
    . 2012, 1(6): 93-95.
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    A new tomato（Lycopersicon esculentum Mill.）male sterile line was created by crossing tomato positional male sterile line TL431 as female parent and indehiscent anther male sterile line T69 as male parent．The hybrid progeny was selected by mass and pedigree selecting method of 6 generations and created a new tomato male sterile line（PSL）which have long stigma and indehiscent anther．This new tomato male sterile line has lots of virtue，such as: easy to accept pollen，sterility degree to be 100% and to be maintained easily by artificial pollination，etc．This new tomato seed production technology can not only save time and energy，but also guarantee the purity of hybrid seed．
  • An Autumn Early Maturing New Chinese Cabbage F1 Hybrid —‘Degao 16’
    ZHANG Dong-qin，LUAN Zhao-shui，ZHANG Jie
    . 2012, 1(6): 96-98.
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    ‘Degao 16’is an autumn early maturing Chinese cabbage F1 hybrid．Its parents are high generation inbred incapability line QG32578 and Summer 93．It took part in the national autumn early maturing Chinese cabbage regional experiment in 2006-2007．In 2007，it also took part in the national autumn early maturing Chinese cabbage production experiment and passed through the identification of the National Crop Variety Approval Committee in 2008．‘Degao 16’is of early maturity．Its growing period lasts 60-65 d．It is 34 cm in plant height，59 cm in development width．The leaf color is green．There are 9 outer leaf blades．Its head is compact and of short cylinder shape．It is resistant to virus disease，downy mildew，black rot．The average net yield is 60 t?hm-2．It is suitable to grow in Shandong，Hebei，Henan，Anhui，Shanxi，Yunnan，Sichuan Provinces and the middle and lower valley of the Yangtze River.
  • A New Cowpea Variety —‘Xiangjiang 2001-4’
    JIANG Ting-jie，DAI Si-hui，XIAO Jie*
    . 2012, 1(6): 99-101.
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    According to the condition of Hunan Province cowpea production in spring cultivation is more rainfall and cowpea varieties are very easy to grow rapidly，we selected‘Changjiang No. 3’，which is endurable to fertility and grow up slowly as female parent and‘Qiweiqing’as male parent．After 10 years’continuous and systematic cross breeding，‘Xiangjiang 2001-4’was developed．This variety was an earlier variety did not grow very fast．It can be cultivated in spring．Its total growing period is about 100-110 d．It can be harvested 45-50 d after sowing．The plant is sprawled with 3-5 branches．The main vine is about 3 m in length．The first flower sets on the 3-5th nodes．The first flower bears 2-4 pods．The flower is light purple in color．The pod is green white in color，59 cm in length，and 0.84 cm in diameter．The single pod weight is about 28 g．There are 18 seeds in a single pod．In field investigation，its resistance to corcospora fuligenae and rust is equal to that of the contrast‘Zhijiang 28-2’．It yields about 37.5 t?hm-2．It is suitable to be cultivated in spring，summer and autumn.
  • A New White Hot Pepper F1 Hybrid —‘Qujiao No. 1’
    LIU Hui-qin，ZHANG Xin-hui，LI Chao-sen，XIANG Xiao-min，XU Jian-xiang
    . 2012, 1(6): 102-103.
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    ‘Qujiao No. 1’is a new white hot pepper F1 hybrid developed by crossing 05B03 as female parent and Y802 as male parent．It is a mid-early mature．The first flower sets at 9-11th node．The plant has continuous fruiting capacity with strong resistance．Its fruit is of cavel shape and yellow and white in color．It tastes middle hot and has food commercial quality．The fruit is 17 cm long，and about 2 cm wide．Its fresh is 0.2 cm thick and single fruit weight is 18 g．It yields about 36.0 t?hm-2．It is suitable to be cultivated in early spring，or over-autumn in green house or mountainous areas in Zhejiang Province.
  • A New Dried Pepper F1 Hybrid —‘Qianjiao No. 6’
    LI Zheng-li1，2，YANG Xin-cheng1，2*，HU Ming-wen1，2，YUAN Yuan-guo1，2，ZHU Wen-chao1，2，HE Ming-de3，WANG Xiao-li4
    . 2012, 1(6): 104-106.
    Abstract ( ) Download PDF ( )   Knowledge map   Save
    ‘Qianjiao No. 6’is a new dried pepper F1 hybrid bred by crossing H20-1 as female parent with H33-2 as male parent．Its fruit is 16.84 cm in length，1.41 cm in width．The fruit color is bright red．The fresh single fruit weight is 11.69 g，and dried single fruit weight is 1.89 g．Its fruit skin is shrink．The VC content is 1 910 mg?kg-1．That of capsaicin and dihydrocapsaicin is 0.020% and 0.000 5%，respectively．Its disease resistance in field is equal to the contrast‘Zunjiao No. 2’．It is suitable to be cultivated in the dried pepper production base in mountain areas of Guizhou Province．
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