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Effect of shading on tomato plants grow under greenhouse
Sandri, Miguel Angelo;Andriolo, Jer?nimo Luiz;Witter, Marcio;Dal Ross, Tiago;
Horticultura Brasileira , 2003, DOI: 10.1590/S0102-05362003000400013
Abstract: the experiment was conducted at universidade federal de santa maria, rio grande do sul state, brazil, to determine the effect of shading on tomato plants grown in a greenhouse. sowing was done on july 4th and planting on august 27th, 2000, in a plant density of 3.3 plants m-2, using an organic commercial rooting medium. water and nutrients were supplied on a daily basis using a nutrient solution. two polyethylene tunnels (2.20 m height, 5 m width, 15 m length) were used. in the first plastic tunnel, used as control, the transmissivity of global radiation was 83% and plants were conducted as a commercial crop. in the second tunnel, plants were grown under a 52% shading screen. plant growth and development were measured at 19; 26; 33; 40; 47; 54; 61; 75 and 89 days after beginning of anthesis. daily average solar radiation in the first tunnel from planting time to the end of the experiment was 12.4 mj m-2 day-1, whereas in the shaded tunnel it was 5.0 mj m-2 day-1. number of fruits per square meter did not differ significantly between the unshaded control and shaded tomato plants. at the last harvest, dry mass from unshaded and shaded plants differed significantly, with values of 974.9 g m-2 and 762.5 g m-2 for total dry mass, 550.1 g m-2 and 419.74 g m-2 for fruits, and 424.75 g m-2 and 342.74 g m-2 for vegetative organs, respectively. total plant growth was reduced to 21.7% by shading, but plants continued to grow, in spite of the radiation level below the trophic limit of 8.4 mj m-2 day-1. to establish the climatic suitability of horticultural crops in different regions, it should be advisable to take in account other variables than solar radiation.
Effect of shading on tomato plants grow under greenhouse  [cached]
Sandri Miguel Angelo,Andriolo Jer?nimo Luiz,Witter Marcio,Dal Ross Tiago
Horticultura Brasileira , 2003,
Abstract: The experiment was conducted at Universidade Federal de Santa Maria, Rio Grande do Sul State, Brazil, to determine the effect of shading on tomato plants grown in a greenhouse. Sowing was done on July 4th and planting on August 27th, 2000, in a plant density of 3.3 plants m-2, using an organic commercial rooting medium. Water and nutrients were supplied on a daily basis using a nutrient solution. Two polyethylene tunnels (2.20 m height, 5 m width, 15 m length) were used. In the first plastic tunnel, used as control, the transmissivity of global radiation was 83% and plants were conducted as a commercial crop. In the second tunnel, plants were grown under a 52% shading screen. Plant growth and development were measured at 19; 26; 33; 40; 47; 54; 61; 75 and 89 days after beginning of anthesis. Daily average solar radiation in the first tunnel from planting time to the end of the experiment was 12.4 MJ m-2 day-1, whereas in the shaded tunnel it was 5.0 MJ m-2 day-1. Number of fruits per square meter did not differ significantly between the unshaded control and shaded tomato plants. At the last harvest, dry mass from unshaded and shaded plants differed significantly, with values of 974.9 g m-2 and 762.5 g m-2 for total dry mass, 550.1 g m-2 and 419.74 g m-2 for fruits, and 424.75 g m-2 and 342.74 g m-2 for vegetative organs, respectively. Total plant growth was reduced to 21.7% by shading, but plants continued to grow, in spite of the radiation level below the trophic limit of 8.4 MJ m-2 day-1. To establish the climatic suitability of horticultural crops in different regions, it should be advisable to take in account other variables than solar radiation.
Rhizosphere bacteria help protein accumulation in soybean seeds  [cached]
Marius Stefan,Marius Mihasan,Lucian Raus,Denis Topa
Analele ?tiin?ifice Ale Universit??ii Alexandru Ioan Cuza din Ia?i,Sectiunea II A : Genetica si Biologie Moleculara , 2009,
Abstract: The use of rhizobacteria as biofertilizers is one of the most promising biotechnologies to improve primary production with low inputs in fertilizers. In this context, the main goal of this study was to establish if the interaction between different rhizobacteria strains with Glycine max L. plants have a positive effect on the total soluble protein, carbohydrates and lipids content of soybeans. Our results revealed that there are no significant differences between the seeds produced by inoculated plants and those produced by the non-inoculated plants regarding soluble reducing carbohydrate content, lipid content and relative humidity. In the case of soluble protein content, rhizobacteria inoculated plants produce beans that contain a greater amount of soluble protein per gram. No qualitative differences could be shown, making our tested rhizobacteria strains an appealing strategy for improving soybean protein production.
Symbiosis of nodule bacteria with perennial xerophyte leguminous plants of Central Asia  [PDF]
Zair S. Shakirov, Sardor A. Khakimov
Agricultural Sciences (AS) , 2010, DOI: 10.4236/as.2010.11004
Abstract: From nodules of perennial xerophyte desert leguminous plants – Ammodendron conollyi, Astragalus villossimus, Astragalus unifoliolatus – 151 bacterial isolates have been isolated. The study of nodulation showed that AC8-1, AC11, AC21, AC1-1, AC12-1 isolates (from Ammodendron conollyi), AV1, AV8-1, AV9, AV26-1, AV36-1 isolates (from Astragalus villossimus) and AU17-1, AU30-1, AU30-2, AU20-1, AU23 isolates (from Astragalus unifoliolatus) formed an effective nitrogen-fixing symbiosis with the host plants. As a result of 16S rRNA gene study of the salt-resistant nodule bacteria it has been determined that bacteria were related to Rhizobium, Burkholderia and Achromobacter genera. The study of isolates growth has revealed that there were fast-growing and moderately-grow- ing isolates that possessed with doubling-time varying from 20 to 45 min. Their examination for antibiotic-resistance showed that the number of bacterial colonies of selected strains decreased to some extent in the presence of chloramphenicol, but in all strains the resistance to antibiotics was detected. The further investigations of resistance of the formed symbiosis to stresses (drought, salinity) showed that at 6.41% of moisture the maximal height and biomass of inoculated plants of Ammodendron conollyi were 21 cm and 2320 mg, but at 3.8% moisture the height reduced by 4 times (up to 4.5 cm) and the biomass – by 11 times (203 mg). The analogous effect was observed in Astragalus villossimus and Astragalus unifoliolatus symbiosises. The salinity equal to 100-200 mM NaCl did not affect practically on normal growth and development of desert leguminous plants symbiosis, while for Astragalus villossimus such affecting concentration comprised up to 100 mM NaCl. The light microscopy and electron microscopy of Astragalus villossimus nodule sections showed that V1 nodule bacteria strain efficiently colonized the internal space within nodules, where they were transformed into bacteroids. At 100 mM NaCl salinity concentration the colonization of nodule bacteria within nodule plant cells reduced in comparison with control nodules of plants grown in non-salted conditions.
PLANTS AS AN ECOLOGICAL NICHE FOR HUMAN PATHOGENIC BACTERIA Растения как экологическая ниша патогенных для человека бактерий
Markova Y. A.,Turskaya A. L.
Polythematic Online Scientific Journal of Kuban State Agrarian University , 2012,
Abstract: The facts related to contamination of plants with pathogenic bacteria being a possible source of human foodborne intestinal diseases are discussed. Data bound up with influence of environment conditions with respect to attachment and penetration of bacteria in plant tissues are described. Exquisite results related to the rate of proliferation and the time of retaining enteropathogens in plant organisms are presented
HERBASPIRILLUM-LIKE BACTERIA IN BANANA PLANTS
Weber, Olmar B.;Cruz, Leonardo M.;Baldani, José I.;D?bereiner, Johanna;
Brazilian Journal of Microbiology , 2001, DOI: 10.1590/S1517-83822001000300007
Abstract: diazotrophic bacteria isolated from banana plants were characterized by morphological and physiological aspects. three different groups of these plant-bacteria could be established. two of them showed similarity to species of the herbaspirillum genus. the third one was different because used only a few carbon substrates and produced water diffusible compounds that fluoresced under uv light. all three bacterial groups were thin rods with mono or bipolar flagella, presented negative reaction in gram stain, showed catalase activity, were able to reduce nitrate and grew better in semi-solid jnfb medium at 31oc. the nitrogenase activity was detected in semi-solid n-free jnfb medium and expressed higher values when ph ranged from 6.5 to 7.0 (groups i and ii) and 6.0 to 6.5 (group iii). the diazotrophs isolated from banana plants were distinct from species of herbaspirillum previously identified in gramineous plants.
HERBASPIRILLUM-LIKE BACTERIA IN BANANA PLANTS  [cached]
Weber Olmar B.,Cruz Leonardo M.,Baldani José I.,D?bereiner Johanna
Brazilian Journal of Microbiology , 2001,
Abstract: Diazotrophic bacteria isolated from banana plants were characterized by morphological and physiological aspects. Three different groups of these plant-bacteria could be established. Two of them showed similarity to species of the Herbaspirillum genus. The third one was different because used only a few carbon substrates and produced water diffusible compounds that fluoresced under UV light. All three bacterial groups were thin rods with mono or bipolar flagella, presented negative reaction in Gram stain, showed catalase activity, were able to reduce nitrate and grew better in semi-solid JNFb medium at 31oC. The nitrogenase activity was detected in semi-solid N-free JNFb medium and expressed higher values when pH ranged from 6.5 to 7.0 (groups I and II) and 6.0 to 6.5 (group III). The diazotrophs isolated from banana plants were distinct from species of Herbaspirillum previously identified in gramineous plants.
Uniform categorization of biocommunication in bacteria, fungi and plants  [cached]
Günther Witzany
World Journal of Biological Chemistry , 2010,
Abstract: This article describes a coherent biocommunication categorization for the kingdoms of bacteria, fungi and plants. The investigation further shows that, besides biotic sign use in trans-, inter- and intraorganismic communication processes, a common trait is interpretation of abiotic influences as indicators to generate an appropriate adaptive behaviour. Far from being mechanistic interactions, communication processes within organisms and between organisms are sign-mediated interactions. Sign-mediated interactions are the precondition for every cooperation and coordination between at least two biological agents such as cells, tissues, organs and organisms. Signs of biocommunicative processes are chemical molecules in most cases. The signs that are used in a great variety of signaling processes follow syntactic (combinatorial), pragmatic (context-dependent) and semantic (content-specific) rules. These three levels of semiotic rules are helpful tools to investigate communication processes throughout all organismic kingdoms. It is not the aim to present the latest empirical data concerning communication in these three kingdoms but to present a unifying perspective that is able to interconnect transdisciplinary research on bacteria, fungi and plants.
Patterns that Grow  [PDF]
William J. Bruno
Physics , 2004,
Abstract: Chemotactic bacteria have been observed to congregate into highly regular patterns. When the bacteria are placed in the center of a dish, a wave of bacteria can travel outward, leaving a regular pattern of spots or stripes in its wake. Although chemotaxis and excretion of an attractant can readily cause a pattern forming instability from a uniform state, they are not capable of generating patterns starting from a single spot. These patterns are apparently formed with the help of bacterial growth and depletion of nutrients in the growth medium.
The Genetic Diversity of Endophytic and Phyllosphere Bacteria from Several Indonesian Herbal Plants
Yogiara, Susan Soka,Stella Magdalena,Devi Rachelia
Makara Seri Sains , 2012,
Abstract: Herbal plants have been believed by Indonesians to be an alternative medicine to treat illnesses. The bioactivecompounds in the plant can be derived from secondary metabolites or from endophytic and phyllosphere bacteria whichcoexist within medicinal plants. A total of 18 endophytic bacteria and 32 phyllosphere bacteria were isolated from theherbal plants of Citrus sp., Pluchea indica, Curcuma longa, Nothopanax scuttelarium, Piper crocatum, andAndrographis paniculata. About 72% of endophytic bacteria isolates have proteolytic activity and about 11% havelipolytic activity. On the other hand, about 59% of phyllosphere bacteria isolates have proteolytic activity and about19% have lipolytic activity. Phylogenetic diversity analysis was conducted by using the amplified ribosomal DNArestriction analysis (ARDRA) method and the sequence of 16S rDNA was digested with endonuclease restrictionenzymes: MspI, RsaI, and Sau961. The diversity of endophytic and phyllosphere bacterium from the samples of herbalplants was high. Bacteria isolated from the same herbal plant does not always have a close genetic relationship exceptfor the bacteria isolated from the P. indica plant which showed a close genetic relationship with each other.
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