The responses of three cultivars of Chinese cabbage (Brassica chmensis L.), one of the main vegetable crops in China, to different ratios of NH4+-N/NO3--N was investigated to find the optimal ratio of ammonium to nitr...The responses of three cultivars of Chinese cabbage (Brassica chmensis L.), one of the main vegetable crops in China, to different ratios of NH4+-N/NO3--N was investigated to find the optimal ratio of ammonium to nitrate for maximal growth and to explore ways of decreasing the nitrate content, increasing nitrogen use efficiency of Chinese cabbage, and determining distributions of nitrogen and carbon. Three cultivars of Chinese cabbage were hydroponically grown with three different NH4+-N/NO3--N ratios (0:10…展开更多
Conversion of natural forests into pure plantation forests is a common management practice in subtropical China.To evaluate the effects of forest conversion on soil fertility, microbe numbers and enzyme activities in ...Conversion of natural forests into pure plantation forests is a common management practice in subtropical China.To evaluate the effects of forest conversion on soil fertility, microbe numbers and enzyme activities in topsoils (0-10 cm)were quantified in two 33-year-old monoculture plantations of Castanopsis kawakamii Hayata (CK) and Cunninghamia lanceolata Lamb. (Chinese fir) (CF), and compared to a neighboring relict natural C. kawakamii forest (NF), in Sanming,Fujian. Five soil samples were collected once each in January, April, July, September and November in 2000 in each forest for laboratory analysis. Over the sampling year, there were significant differences for bacteria, fungi and actinomycetes between forests and between seasons (P ＜ 0.05). The largest bacteria and fungi populations were in NF, while CF contained the greatest number of actinomycetes. There were also significant differences (P ＜ 0.05) with microbial respiration for forests and seasons. Additionally, compared with NF, urease and acid phosphatase were significantly lower (P ＜ 0.05)in CK and CF. Also, the correlations of soil hydrolysable N and available P to soil microbial and enzymatic activities were highly significant (P ＜ 0.01). Thus, to alter the traditional Chinese fir monoculture so as to mimic the natural forest conditions, managing mixed stands of Chinese fir and broadleaf trees or conducting crop rotation of conifers and broadleaf trees as well as minimizing forest disturbances like clear-cutting, slash burning and soil preparing, could be utilized.展开更多
C. acuminata seedlings cultivated in greenhouse were transplanted into the fields with 5 designed planting densities (11, 16, 25,44 and 100 plants·m^-2) in May of 2004 and were harvested in the middle of Septembe...C. acuminata seedlings cultivated in greenhouse were transplanted into the fields with 5 designed planting densities (11, 16, 25,44 and 100 plants·m^-2) in May of 2004 and were harvested in the middle of September of 2004. The seedling growth indexes including plant height and crown width, biomass allocation, camptothecin (CPT) content and CPT yield of different organs (young leaf, old leaf, stem,and root) were studied. For the 5 selected planting densities, the plant biomass, height, crown width, and total leaf area of C. acuminata seedlings all showed highest values at the planting density of 25 plants ·m^-2. CPT content in young leaves was higher than that in other organs of seedlings and presented an obvious change with the variation of planting densities and with the highest value at density of 100plants·m-2, while for other organs no significant variation in CPT content was found with change of planting density. The accumulation of CPT was enhanced significantly at the planting density of 25 plants·m^-2. It is concluded that for the purpose to get raw materials with more CPT from C. acuminata, the optimal planting density of C. acuminata seedlings should be designed as 25 plants·m^-2.展开更多
Agave americana Var. Marginata Hort. （Agavaceae） is a perennial herb. This paper summarized its classification, distribution, morphological characteristics, habit, flowering and fruiting, cultivation and reproductio...Agave americana Var. Marginata Hort. （Agavaceae） is a perennial herb. This paper summarized its classification, distribution, morphological characteristics, habit, flowering and fruiting, cultivation and reproduction, as well as multiple uses in daily life, which provided references for the exploitation and utilization of Agave americana Vat. Marginata Hort. （Agavaceae）.展开更多
Chinese cabbage was cultivated in upland soil with the addition of biochar in order to investigate the potential for reduction of greenhouse gas emissions. Barley straw biochar(BSB) was introduced in a Wagner pot(1/50...Chinese cabbage was cultivated in upland soil with the addition of biochar in order to investigate the potential for reduction of greenhouse gas emissions. Barley straw biochar(BSB) was introduced in a Wagner pot(1/5000a) in amounts of 0(BSB0, control), 100(BSB100), 300(BSB300), and 500(BSB500) kg 10a^(-1). After the addition of BSB into the upland soil, carbon dioxide(CO_2) emission increased while methane(CH_4) and nitrous oxide(N_2O) emissions decreased. The highest CO2 flux was measured for the BSB500 sample,(84.6 g m^(-2)) followed by BSB300, BSB100, and BSB0 in decreasing order. Relative to those of control, the total CH_4 flux and N_2O flux for the BSB500 treatment were lower by 31.6% and 26.1%, respectively. The global warming potential(GWP) of the treatment without biochar was 281.4 g CO_2 m-2 and those for treatments with biochar were in the range from 194.1 to 224.9 g CO_2 m^(-2). Therefore, introducing BSB into upland soil to cultivate Chinese cabbages can reduce the global warming potential.展开更多
A total 23 morphological traits, 19 AFLP-primer combinations, 80 RAPD primers and 32 SSR primer pair were used to compare the informativeness and efficiency of random amplified polymorphic DNA （RAPD）, amplified frag...A total 23 morphological traits, 19 AFLP-primer combinations, 80 RAPD primers and 32 SSR primer pair were used to compare the informativeness and efficiency of random amplified polymorphic DNA （RAPD）, amplified fragment length polymorphism （AFLP） and simple sequence repeat （SSR） markers in establishing genetic relationships among 29 almond cultivars and three related wild species. SSRs presented a high level of polymorphism and greater information content, as assessed by the expected hetrozygosity, compared to AFLPs and RAPDs. The lowest values of expected hetrozygosity were obtained for AFLPs; however AFLPs showed the highest efficiency, owing to their capacity to reveal large numbers of bands per reaction, which led to high values for various types of indices of diversity. All the three techniques discriminated almond genotypes very effectively, except that SSRs failed to discriminate between ＇Monagha＇ and ＇Sefied＇ almond genotypes. The correlation coefficients of similarity were statistically significant for all the three marker systems, but were lower for the SSR data than for RAPDs and AFLPs. For all the markers, high similarity in dendrogram topologies was obtained, although some differences were observed. All the dendrograms, including that obtained by the combined use of all the marker data, reflect relationships for most of cultivars according to their geographic diffusion. AMOVA detected more variation among cultivated and related wild species of almond within each geographic group. Bootstrap analysis revealed that the number of markers used was sufficient for reliable estimation of genetic similarity and for meaningful comparisons of marker types.展开更多
Endophytes are beneficial microbes that are capable of promoting growth, besides protecting colonized plants against plant pathogens. These microbes are of either bacterial, fungal or actinomycetes in plants. In the s...Endophytes are beneficial microbes that are capable of promoting growth, besides protecting colonized plants against plant pathogens. These microbes are of either bacterial, fungal or actinomycetes in plants. In the study, the endophytic bacteria isolated from sugarcane with their characterization related to plant growth promotion and pathogen suppression have been reported. Roots, shoots and leaves of rooted tissue culture plantlets of sugarcane cultivars of 87A298 and 2009A107 were excised aseptically and isolated endophytic bacterial strains. The strains were identified using 16S rRNA gene sequence based homology. Molecular characterization of these strains was carried out for presence of antimicrobial genes. The results showed that the endophytes isolated from sugarcane tissue culture plantlets were of the genera Bacillus （B. amyloliquefaciens, B. subtilis, B. cereus, B. safensis, B. siamensis, B. aryabhattai, B. flexus and B. velezensis） and Paenibacillus pabuli. There were three antimicrobial peptides （AMPs） producing genes of bacilysin, bacillomycin and fengycin in B. amyloliquefaciens （SE1, SE7）, B. siamensis （SE4, SE16）, B. subtilis （SE2, SE3） and B. velezensis （SE15）. The biochemical characterization assays showed that some of these strains could produce hydrogen cyanide （HCN）, protease, cellulase and indole acetic acid （IAA）. Few strains （SE1 and SE4） were phosphate solubilizers, whereas nine isolates were found to be diazotrophs. Most of the bacterial isolates were found antagonistic to Fusarium sacchari, the sugarcane wilt pathogen under in vitro conditions. Overall, the results suggested the scope and potentiality of sugarcane endophytic bacteria, isolated from tissue culture plantlets, in promoting plant growth and suppression of sugarcane pathogen.展开更多
In a commercialized, fully artificial plant factory, artificial luminaire is arranged in a unified way using a general illumination theory, an actual measurement, or an empirical methodology. However, with these metho...In a commercialized, fully artificial plant factory, artificial luminaire is arranged in a unified way using a general illumination theory, an actual measurement, or an empirical methodology. However, with these methods, lightings are implemented without considering specific optical characteristics of lighting or material characteristics of each component that constructs a cultivation system, resulting in an amount of light that becomes irregular. The amount of lighting is closely related with the growth and quality of crops, and the deviation between points where cultivated crops are located causes quality difference in the produced crops, thus impairing the economic feasibility of a plant factory. In this regard, a simulation to figure out an optimum lighting layout was performed. Arrangements based on the spectrum distribution of light source and reflector materials were implemented to ascertain the distance between lighting and height of lighting and gather information in the pre-treatment process to improve the uniformity of light in the plant cultivation system. Improvement of around 15% in light uniformity is achieved compared with the existing system after the simulation is carried out. This result would reduce the deviation in crop growth to make uniform quality crop production possible.展开更多
基金1 Project supported by the National Natural Science Foundation of China (No. 30270790).
文摘The responses of three cultivars of Chinese cabbage (Brassica chmensis L.), one of the main vegetable crops in China, to different ratios of NH4+-N/NO3--N was investigated to find the optimal ratio of ammonium to nitrate for maximal growth and to explore ways of decreasing the nitrate content, increasing nitrogen use efficiency of Chinese cabbage, and determining distributions of nitrogen and carbon. Three cultivars of Chinese cabbage were hydroponically grown with three different NH4+-N/NO3--N ratios (0:10…
基金the Basic Research Program of Fujian Province (No. 2000-F-004).
文摘Conversion of natural forests into pure plantation forests is a common management practice in subtropical China.To evaluate the effects of forest conversion on soil fertility, microbe numbers and enzyme activities in topsoils (0-10 cm)were quantified in two 33-year-old monoculture plantations of Castanopsis kawakamii Hayata (CK) and Cunninghamia lanceolata Lamb. (Chinese fir) (CF), and compared to a neighboring relict natural C. kawakamii forest (NF), in Sanming,Fujian. Five soil samples were collected once each in January, April, July, September and November in 2000 in each forest for laboratory analysis. Over the sampling year, there were significant differences for bacteria, fungi and actinomycetes between forests and between seasons (P ＜ 0.05). The largest bacteria and fungi populations were in NF, while CF contained the greatest number of actinomycetes. There were also significant differences (P ＜ 0.05) with microbial respiration for forests and seasons. Additionally, compared with NF, urease and acid phosphatase were significantly lower (P ＜ 0.05)in CK and CF. Also, the correlations of soil hydrolysable N and available P to soil microbial and enzymatic activities were highly significant (P ＜ 0.01). Thus, to alter the traditional Chinese fir monoculture so as to mimic the natural forest conditions, managing mixed stands of Chinese fir and broadleaf trees or conducting crop rotation of conifers and broadleaf trees as well as minimizing forest disturbances like clear-cutting, slash burning and soil preparing, could be utilized.
基金This paper was supported by the National Natural Science Foundation of China (No.3970086) and Heilongjiang Province Foundation for Distinguished Youth Scholars (JC-02-11)
文摘C. acuminata seedlings cultivated in greenhouse were transplanted into the fields with 5 designed planting densities (11, 16, 25,44 and 100 plants·m^-2) in May of 2004 and were harvested in the middle of September of 2004. The seedling growth indexes including plant height and crown width, biomass allocation, camptothecin (CPT) content and CPT yield of different organs (young leaf, old leaf, stem,and root) were studied. For the 5 selected planting densities, the plant biomass, height, crown width, and total leaf area of C. acuminata seedlings all showed highest values at the planting density of 25 plants ·m^-2. CPT content in young leaves was higher than that in other organs of seedlings and presented an obvious change with the variation of planting densities and with the highest value at density of 100plants·m-2, while for other organs no significant variation in CPT content was found with change of planting density. The accumulation of CPT was enhanced significantly at the planting density of 25 plants·m^-2. It is concluded that for the purpose to get raw materials with more CPT from C. acuminata, the optimal planting density of C. acuminata seedlings should be designed as 25 plants·m^-2.
文摘Agave americana Var. Marginata Hort. （Agavaceae） is a perennial herb. This paper summarized its classification, distribution, morphological characteristics, habit, flowering and fruiting, cultivation and reproduction, as well as multiple uses in daily life, which provided references for the exploitation and utilization of Agave americana Vat. Marginata Hort. （Agavaceae）.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF)funded by the Ministry of Education,Science and Technology (2012R1A2A2A01015706)the support of "Cooperative Research Program for Agriculture Science & Technology Development (Project No. PJ011227042016)" Rural Development Administration, Republic of Korea
文摘Chinese cabbage was cultivated in upland soil with the addition of biochar in order to investigate the potential for reduction of greenhouse gas emissions. Barley straw biochar(BSB) was introduced in a Wagner pot(1/5000a) in amounts of 0(BSB0, control), 100(BSB100), 300(BSB300), and 500(BSB500) kg 10a^(-1). After the addition of BSB into the upland soil, carbon dioxide(CO_2) emission increased while methane(CH_4) and nitrous oxide(N_2O) emissions decreased. The highest CO2 flux was measured for the BSB500 sample,(84.6 g m^(-2)) followed by BSB300, BSB100, and BSB0 in decreasing order. Relative to those of control, the total CH_4 flux and N_2O flux for the BSB500 treatment were lower by 31.6% and 26.1%, respectively. The global warming potential(GWP) of the treatment without biochar was 281.4 g CO_2 m-2 and those for treatments with biochar were in the range from 194.1 to 224.9 g CO_2 m^(-2). Therefore, introducing BSB into upland soil to cultivate Chinese cabbages can reduce the global warming potential.
文摘A total 23 morphological traits, 19 AFLP-primer combinations, 80 RAPD primers and 32 SSR primer pair were used to compare the informativeness and efficiency of random amplified polymorphic DNA （RAPD）, amplified fragment length polymorphism （AFLP） and simple sequence repeat （SSR） markers in establishing genetic relationships among 29 almond cultivars and three related wild species. SSRs presented a high level of polymorphism and greater information content, as assessed by the expected hetrozygosity, compared to AFLPs and RAPDs. The lowest values of expected hetrozygosity were obtained for AFLPs; however AFLPs showed the highest efficiency, owing to their capacity to reveal large numbers of bands per reaction, which led to high values for various types of indices of diversity. All the three techniques discriminated almond genotypes very effectively, except that SSRs failed to discriminate between ＇Monagha＇ and ＇Sefied＇ almond genotypes. The correlation coefficients of similarity were statistically significant for all the three marker systems, but were lower for the SSR data than for RAPDs and AFLPs. For all the markers, high similarity in dendrogram topologies was obtained, although some differences were observed. All the dendrograms, including that obtained by the combined use of all the marker data, reflect relationships for most of cultivars according to their geographic diffusion. AMOVA detected more variation among cultivated and related wild species of almond within each geographic group. Bootstrap analysis revealed that the number of markers used was sufficient for reliable estimation of genetic similarity and for meaningful comparisons of marker types.
文摘Endophytes are beneficial microbes that are capable of promoting growth, besides protecting colonized plants against plant pathogens. These microbes are of either bacterial, fungal or actinomycetes in plants. In the study, the endophytic bacteria isolated from sugarcane with their characterization related to plant growth promotion and pathogen suppression have been reported. Roots, shoots and leaves of rooted tissue culture plantlets of sugarcane cultivars of 87A298 and 2009A107 were excised aseptically and isolated endophytic bacterial strains. The strains were identified using 16S rRNA gene sequence based homology. Molecular characterization of these strains was carried out for presence of antimicrobial genes. The results showed that the endophytes isolated from sugarcane tissue culture plantlets were of the genera Bacillus （B. amyloliquefaciens, B. subtilis, B. cereus, B. safensis, B. siamensis, B. aryabhattai, B. flexus and B. velezensis） and Paenibacillus pabuli. There were three antimicrobial peptides （AMPs） producing genes of bacilysin, bacillomycin and fengycin in B. amyloliquefaciens （SE1, SE7）, B. siamensis （SE4, SE16）, B. subtilis （SE2, SE3） and B. velezensis （SE15）. The biochemical characterization assays showed that some of these strains could produce hydrogen cyanide （HCN）, protease, cellulase and indole acetic acid （IAA）. Few strains （SE1 and SE4） were phosphate solubilizers, whereas nine isolates were found to be diazotrophs. Most of the bacterial isolates were found antagonistic to Fusarium sacchari, the sugarcane wilt pathogen under in vitro conditions. Overall, the results suggested the scope and potentiality of sugarcane endophytic bacteria, isolated from tissue culture plantlets, in promoting plant growth and suppression of sugarcane pathogen.
基金financially supported by the Ministry of Education, Science, and Technology (MEST)the National Research Foundation of Korea (NRF) through the Human Resource Training Project for Regional Innovationsupported by the Human Resources Development of the Korea Institute of Energy Technology Evaluation and Planning (No.20114010203040) grant funded by the Korean government’s Ministry of Knowledge Economy
文摘In a commercialized, fully artificial plant factory, artificial luminaire is arranged in a unified way using a general illumination theory, an actual measurement, or an empirical methodology. However, with these methods, lightings are implemented without considering specific optical characteristics of lighting or material characteristics of each component that constructs a cultivation system, resulting in an amount of light that becomes irregular. The amount of lighting is closely related with the growth and quality of crops, and the deviation between points where cultivated crops are located causes quality difference in the produced crops, thus impairing the economic feasibility of a plant factory. In this regard, a simulation to figure out an optimum lighting layout was performed. Arrangements based on the spectrum distribution of light source and reflector materials were implemented to ascertain the distance between lighting and height of lighting and gather information in the pre-treatment process to improve the uniformity of light in the plant cultivation system. Improvement of around 15% in light uniformity is achieved compared with the existing system after the simulation is carried out. This result would reduce the deviation in crop growth to make uniform quality crop production possible.
