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Abiotic stresses, such as drought, salinity, heavy metals, variations in temperature, and ultraviolet (UV) radiation, are antagonistic to plant growth and development, resulting in an overall decrease in plant yield. These stresses have direct effects on the rhizosphere, thus severely affect the root growth, and thereby affecting the overall plant growth, health, and productivity. However, the growth-promoting rhizobacteria that colonize the rhizosphere/endorhizosphere protect the roots from the adverse effects of abiotic stress and facilitate plant growth by various direct and indirect mechanisms. In the rhizosphere, plants are constantly interacting with thousands of these microorganisms, yet it is not very clear when and how these complex root, rhizosphere, and rhizobacteria interactions occur under abiotic stresses. Therefore, the present review attempts to focus on root–rhizosphere and rhizobacterial interactions under stresses, how roots respond to these interactions, and the role of rhizobacteria under these stresses. Further, the review focuses on the underlying mechanisms employed by rhizobacteria for improving root architecture and plant tolerance to abiotic stresses.

Stress drought is an important abiotic factor that leads to immense losses in crop yields around the world. Strategies are urgently needed to help plants adapt to drought in order to mitigate crop losses. Here we investigated the bioprotective effects of inoculating corn grown under drought conditions with two types of plant growth-promoting rhizobacteria (PGPR), A. brasilense, strain SP-7, and H. seropedicae, strain Z-152. Plants inoculated with the bacteria were grown in a greenhouse with perlite as a substrate. Two hydric conditions were tested: normal well-watered conditions and drought conditions. Compared to control non-inoculated plants, those that were inoculated with PGPR bacteria showed a higher tolerance to the negative effects of water stress in drought conditions, with higher biomass production; higher carbon, nitrogen, and chlorophyll levels; and lower levels of abscisic acid and ethylene, which are plant hormones that affect the stress response. The oxidative stress levels of these plants were similar to those of non-inoculated plants grown in well-watered conditions, showing fewer injuries to the cell membrane. We also noted higher relative water content in the vegetal tissue and better osmoregulation in drought conditions in inoculated plants, as reflected by significantly lower proline content. Finally, we observed lower gene expression of ZmVP14 in the inoculated plants; notably, ZmVP14 is involved in the biosynthesis of abscisic acid. Taken together, these results demonstrate that these bacteria could be used to help plants cope with the negative effects of drought stress conditions. Fil: Curá, José Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Agronomía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales; Argentina Fil: Franz, Diego Reinaldo. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Filosofía, Julián Ezequiel. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Balestrasse, Karina Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Burgueño, Lautaro Exequiel. Universidad de Buenos Aires. Facultad de Agronomía; Argentina

We measured phosphorus uptake by rice plants inoculated with plant growth-promoting bacteria (PGPB) using Pseudomonas sp. strain PAC, Serratia sp. strain CMR165, and Azospirillum brasilense strain FT326. We measured plant growth parameters and phosphate solubilization and uptake. Results show that the ability to solubilize phosphates varied among PGPB strains. Strain FT326 was unable to solubilize phosphates. In the presence of glucose, PAC and CMR165 can solubilize inorganic tricalcium phosphate and organic calcium magnesium inositol hexaphosphate. Phosphate solubilization by strains PAC and CMR165 was different over time; FT326 was similar to the untreated control. Plants inoculated with PAC or CMR165 had higher concentrations of phosphates than those inoculated with FT326 and plants that were not inoculated. Glucose was the only sugar identified in rice root exudates. PAC and CMR165 promoted plant growth and uptake of phosphate and could be used as biofertilizers to optimize phosphate fertilization.

Rice seedlings (Oryza sativa) inoculated with the plant growth-promoting rhizobacteria Azospirillum brasilense FT326 showed an enhanced development of the root system 3 days after inoculation. Later on, a remarkable enlargement of shoots was also evident. An increase in the Ca2+-dependent histone kinase activity was also detected as a result of inoculation. The biochemical characterization and Western-blot analysis of the kinase strongly supports the hypothesis that it belongs to a member of the rice CDPK family. The fact that the amount of the protein did not change upon inoculation seems to indicate that a posttranslational activation is responsible for the change in the enzymatic activity. An in-gel kinase experiment identified a 46 kDa CDPK like protein kinase as a putative component of the signal transduction pathway triggered by Azospirillum inoculation. To our knowledge, this is the first report on the possible involvement of a Ca2+-dependent protein kinase in promotion of rice plants growth by A. brasilense.

The capability of native bacterial strains isolated from Lolium perenne rhizosphere to behave as plant growth promoting bacteria and /or biocontrol agents was investigated. One strain (BNM 0357) over 13 isolates from the root tips of L. perenne resulted proved to be nitrogenase positive (ARA test) and an IAA producer. Conventional tests and the API 20E diagnostic kit indicated that BNM 0357 behaves to the Enterobacteriaceae family and to the Enterobacter genus. Molecular identification by 16S rRNA sequence analysis indicated that BNM 0357 had the highest similarity to Enterobacter ludwigii (EN-119). Isolate BNM 0357 had the capability to solubilize calcium triphosphate and to antagonize Fusarium solani mycelial growth and spore germination. Strain BNM 0357 also showed the ability to improve the development of the root system of L. perenne. This study disclosed features of E. ludwigii BNM 0357 that deserve further studies aimed at confirming its putative importance as a PGPR.

The variations of organic and amino acids in rice plants inoculated with Herbaspirillum seropedicae were analyzed in contrast with those of non-inoculated plants to provide information about plant-bacteria interaction. Inoculated plants showed higher contents of key amino acids of nitrogen assimilation that were more than five-fold higher than those of control plants, in the aerial tissues. At the same time, inoculated plants showed malate levels about twice as high as those found in control plants. Moreover, both ethylene production and ACS activity increased due to the inoculation with H. seropedicae. This is the first report on the ethylene and malate involvement in the metabolic response of rice to the inoculation with H. seropedicae.

Grain protein content is one of the most important attributes in bread making quality. Several studies have reported that the type of, and the balances between, storage protein (i.e. gliadins and glutenins) are also relevant. Generally, the modern cultivars present less grain protein content than their predecessors, suggesting that breeding may have reduced baking quality while improving yield. Furthermore, there is little information on whether, and eventually how, breeding influences the types of protein synthesized in the grains, and the sensitivity of the type of protein and baking quality to changes in the environment. This study aimed to determine the stability in baking quality in wheat cultivars released at different eras to variation in the duration of the pre-anthesis period without changes in the sowing date. The experiment studied the combination of three cultivars released in 1940, 1964 and 1994 at two different durations from sowing to anthesis (because of exposure to different photoperiods during stem elongation in the field). Modern cultivars showed lower grain protein content than the oldest ones (11 vs. 14 %). There were no correlation between grain protein content and baking quality (assessed by Zeleny test), indicating that protein type is more important than grain protein content. Gliadins were more variable than glutenins because of differences between cultivars and flowering dates. Wheat breeding also seemed to have improved the stability of quality variables in response to environmental variation during the pre-anthesis period (when yield potential is being determined).

In maize (Zea mays L.), there is little information on how the availability of assimilates during the effective grain-filling period affect final kernel quality. The objective of our research was to analyze the response of kernel starch, protein, and oil to changes in the post-flowering source-sink ratio (i.e., post-flowering shoot biomass increase per kernel). Two commercial hybrids of different kernel weight (KW) and protein content were grown at two stand densities (3 and 9 plants m -2 ) during 1998-1999 and 1999-2000. Pollination treatments were used to modify kernel number per plant (KNP). As KNP increased, starch, protein and oil yield per plant increased, but yield per kernel decreased (P < 0.05) in all treatment combinations. In both genotypes, starch, protein, and oil content per kernel varied between 114 to 238, 15 to 48, and 7 to 17 mg kernel -1 , respectively, and concentrations varied between 650 to 700, 80 to 140, and 40 to 60 g kg -1 dry weight, respectively. Within each hybrid, the post-flowering source-sink ratio explained (P < 0.01) the response of each kernel component content to modifications in KNP and stand density. In both genotypes, kernel starch, protein, and oil content were all maximized at the same post-flowering source-sink ratio (∼420 and 570 mg kernel -1 in DK664 and DK752, respectively). A decrease in the source-sink ratio beyond a specific threshold promoted a decrease in the relative protein content and an increase in the relative starch content. Limitations other than assimilates seem to govern the relative oil content of kernels, as no relation with the post-flowering source-sink ratio was found.

Phosphorus is an essential nutrient for plant growth and yield. Currently, phosphorus fixation in soil is a major problem throughout the world as available phosphorus in soil is highly reactive with cationic elements to form complex compounds. Rock phosphate is one of the cheapest fertiliser and most abundant; however, its direct application in soils is not much effective for the availability of phosphorus to plant growth due to its low reactivity. Further, phosphorus is present as a fixed or complex form in soils, which is unavailable for plants. Phosphate solubilising microbes (PSMs) have potential to solubilise the complex form of phosphate in the available form of phosphorus to plants. PSMs have different mechanisms for solubilisation of phosphate by producing various acids and enzymes. Other mechanisms of phosphate solubilisation and mineralisation follow chelation and immobilised cell technology. All such phosphate solubilisation mechanisms by PSMs have been discussed in this article. The current need to develop genetically modified PSM as efficient PSMs strains for sustainable agricultural production is also discussed in the present review. The PSMs is known as effective biofertiliser for enhancing the plant growth, yield and nutrient content in crops as well as improve the soil fertility under sustainable agriculture. The main aim of this review was to elaborate the phosphate solubilising activities and their consequences for sustainable agriculture.

The maize (Zea mays L.) plants inoculated by N2-fixing bacterium Azospirillum showed increased activity of glutamate dehydrogenase (GDH) and glutamine synthetase (GS) in root cells free extracts over uninoculated control plants. Maximum differences in NADH-GDH activity were observed during the second and third weeks after sowing. The specific activity of GS showed a greater increase at the end of the assay. The percentage of nitrogen in leaves, root and foliage length, total fresh mass and nitrogenase activity were higher in inoculated plants than in the control ones.

The present study was conducted in order to evaluate the starch components contained in several maize mutants. The α1,4-α1,6 glucopolysaccharides were fractionated according to their branching degree. The determination of the wavelenght of maximum absorption (γ max) in the presence of Krisman's reagent [12] as well as the glucose α1,6 linkages involved in the branching point were determined. The mutants analyzed possess characteristics that allow us to identify them according to the composition and structural properties of their polysaccharides (phytoglycogen, amylopectin, amylose). Maismutanten. Teil 1: Untersuchungen uber ihre Starkekomponenten. Die vorliegende Untersuchung wurde durchgefuhrt, um die in verschiedenen Maismutanten enthaltenen Starkekomponenten zu bewerten. Die α1,4-α1,6-Glucopolysaccharide wurden entsprechend ihrer Verzweigungsgrade fraktioniert. Die Bestimmung der Wellenlange der maximalen Absorption (γ max) in Gegenwart von Krisman's Reagens [12] als auch die im Verzweigungspunkt involvierten Glucose α1,6-Bindungen wurden bestimmt. Die analysierten Mutanten besitzen Charakteristika, die uns erlauben, sie mit der Zusammensetzung und den strukturellen Eigenschaften ihrer Polysaccharide (Phytoglykogen, Amylopektin, Amylose) zu identifizieren.

BACKGROUND: Plants use different light signals to adjust their growth and development to the prevailing environmental conditions. Studies in the model species Arabidopsis thaliana and rice indicate that these adjustments are mediated by large changes in the transcriptome. Here we compared transcriptional responses to light in different species of the Solanaceae to investigate common as well as species-specific changes in gene expression. RESULTS: cDNA microarrays were used to identify genes regulated by a transition from long days (LD) to short days (SD) in the leaves of potato and tobacco plants, and by phytochrome B (phyB), the photoreceptor that represses tuberization under LD in potato. We also compared transcriptional responses to photoperiod in Nicotiana tabacum Maryland Mammoth (MM), which flowers only under SD, with those of Nicotiana sylvestris, which flowers only under LD conditions. Finally, we identified genes regulated by red compared to far-red light treatments that promote germination in tomato. CONCLUSION: Most of the genes up-regulated in LD were associated with photosynthesis, the synthesis of protective pigments and the maintenance of redox homeostasis, probably contributing to the acclimatization to seasonal changes in irradiance. Some of the photoperiodically regulated genes were the same in potato and tobacco. Others were different but belonged to similar functional categories, suggesting that conserved as well as convergent evolutionary processes are responsible for physiological adjustments to seasonal changes in the Solanaceae. A beta-ZIP transcription factor whose expression correlated with the floral transition in Nicotiana species with contrasting photoperiodic responses was also regulated by photoperiod and phyB in potato, and is a candidate gene to act as a general regulator of photoperiodic responses. Finally, GIGANTEA, a gene that controls flowering time in Arabidopsis thaliana and rice, was regulated by photoperiod in the leaves of potato and tobacco and by red compared to far-light treatments that promote germination in tomato seeds, suggesting that a conserved light signaling cascade acts across developmental contexts and species Fil: Rutitzky, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Ghiglione, Hernán O.. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Curá, José Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales; Argentina Fil: Casal, Jorge José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Yanovsky, Marcelo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina

The wheat spikelet meristem differentiates into up to 12 floret primordia, but many of them fail to reach the fertile floret stage at anthesis. We combined microarray, biochemical and anatomical studies to investigate floret development in wheat plants grown in the field under short or long days (short days extended with low-fluence light) after all the spikelets had already differentiated. Long days accelerated spike and floret development and greening, and the expression of genes involved in photosynthesis, photoprotection and carbohydrate metabolism. These changes started while the spike was in the light-depleted environment created by the surrounding leaf sheaths. Cell division ceased in the tissues of distal florets, which interrupted their normal developmental progression and initiated autophagy, thus decreasing the number of fertile florets at anthesis. A massive decrease in the expression of genes involved in cell proliferation, a decrease in soluble carbohydrate levels, and an increase in the expression of genes involved in programmed cell death accompanied anatomical signs of cell death, and these effects were stronger under long days. We propose a model in which developmentally generated sugar starvation triggers floret autophagy, and long days intensify these processes due to the increased carbohydrate consumption caused by the accelerated plant development. © 2008 The Authors.

The glucopolysaccharides containing α-1,4 and α-1,6 linkages present in the endosperm of mature cereal seeds (corn, wheat and rice) were fractionated according to their branching degree. An already published method [19] was used to specifically estimate the α-1,6 linked glucoses involved in the branching points. The following features were found: a) Starches from different tissues vary in their relative amount of amylose and amylopectin. b) Amylose is present either as a strictly linear or additionally as a lowly branched polysaccharide. c) Amylopectins with a rather wide range of branching degrees were detected. A redefinition of the starch α-1,4—α-1,6 glucopolysaccharides based on their λmax and percentages of glucoses in branching points was introduced. A linear correspondence between brauching points and the maximum absorption (λmax) in the presence of Krisman's iodine reagent was obtained. Getreidekorner: Eine Untersuchung uber ihre Zusammensetzung an α-1,4- und α-1,6-Glucopolysacchariden. Die im Endosperm reifer Getreidekorner (Mais, Weizen und Reis) anwesenden, α-1,4- und α-1,6-Bindungen enthaltenden Glucopolysaccharide wurden entsprechend ihrem Verzweigungsgrad fraktioniert. Zur spezifischen Bestimmung der in den Verzweigungsstellen enthaltenen α-1,6-verbundenen Glucosemolekule wurde eine bereits veroffentlichte Methode angewendet. Die folgenden Merkmale wurden festgestellt: a) Starken aus verschiedenen Zellgeweben unterscheiden sich in ihrem relativen Gehalt an Amylose und Amylopektin. b) Amylose liegt entweder als streng lineares oder zusatzlich als gering verzweigtes Polysaccharid vor. c) Amylopektine mit weiten Bereichen an Verzweigungsgraden wurden gefunden. Eine neue Definition der Starke-α-1,4- und α-1,6-Glucopolysaccharide aufgrund ihres λmax und Glucoseprozentsatzes an den Verzweigungsstellen wurde eingefuhrt. Ein linearer Zusammenhang zwischen Verzweigungsstellen und der maximalen (λmax) Absorption in Gegenwart des Iodreagens nach Krisman wurde erhalten.

Tomato seeds were inoculated with the plant growth–promoting rhizobacteria Azospirillum brasilense FT326, and changes in parameters associated with plant growth were evaluated 15 days after inoculation. Azospirilla were localized on roots and within xylematic tissue. An increase in shoot and root fresh weight, main root hair length, and root surface indicated that inoculation with A. brasilense FT 326 resulted in plant growth improvement. The levels of indole-3-acetic acid (IAA) and ethylene, two of the phytohormones related to plant growth, were higher in inoculated plants. Exogenously supplied ethylene mimicked the effect of inoculation, and the addition of an inhibitor of its synthesis or of its physiological activity completely blocked A. brasilense growth promotion. Based on our results, we propose that the process of growth promotion triggered by A. brasilense inoculation involves a signaling pathway that has ethylene as a central, positive regulator.Azospirillum brasilense FT326, and changes in parameters associated with plant growth were evaluated 15 days after inoculation. Azospirilla were localized on roots and within xylematic tissue. An increase in shoot and root fresh weight, main root hair length, and root surface indicated that inoculation with A. brasilense FT 326 resulted in plant growth improvement. The levels of indole-3-acetic acid (IAA) and ethylene, two of the phytohormones related to plant growth, were higher in inoculated plants. Exogenously supplied ethylene mimicked the effect of inoculation, and the addition of an inhibitor of its synthesis or of its physiological activity completely blocked A. brasilense growth promotion. Based on our results, we propose that the process of growth promotion triggered by A. brasilense inoculation involves a signaling pathway that has ethylene as a central, positive regulator., and changes in parameters associated with plant growth were evaluated 15 days after inoculation. Azospirilla were localized on roots and within xylematic tissue. An increase in shoot and root fresh weight, main root hair length, and root surface indicated that inoculation with A. brasilense FT 326 resulted in plant growth improvement. The levels of indole-3-acetic acid (IAA) and ethylene, two of the phytohormones related to plant growth, were higher in inoculated plants. Exogenously supplied ethylene mimicked the effect of inoculation, and the addition of an inhibitor of its synthesis or of its physiological activity completely blocked A. brasilense growth promotion. Based on our results, we propose that the process of growth promotion triggered by A. brasilense inoculation involves a signaling pathway that has ethylene as a central, positive regulator.Azospirilla were localized on roots and within xylematic tissue. An increase in shoot and root fresh weight, main root hair length, and root surface indicated that inoculation with A. brasilense FT 326 resulted in plant growth improvement. The levels of indole-3-acetic acid (IAA) and ethylene, two of the phytohormones related to plant growth, were higher in inoculated plants. Exogenously supplied ethylene mimicked the effect of inoculation, and the addition of an inhibitor of its synthesis or of its physiological activity completely blocked A. brasilense growth promotion. Based on our results, we propose that the process of growth promotion triggered by A. brasilense inoculation involves a signaling pathway that has ethylene as a central, positive regulator.A. brasilense FT 326 resulted in plant growth improvement. The levels of indole-3-acetic acid (IAA) and ethylene, two of the phytohormones related to plant growth, were higher in inoculated plants. Exogenously supplied ethylene mimicked the effect of inoculation, and the addition of an inhibitor of its synthesis or of its physiological activity completely blocked A. brasilense growth promotion. Based on our results, we propose that the process of growth promotion triggered by A. brasilense inoculation involves a signaling pathway that has ethylene as a central, positive regulator.resulted in plant growth improvement. The levels of indole-3-acetic acid (IAA) and ethylene, two of the phytohormones related to plant growth, were higher in inoculated plants. Exogenously supplied ethylene mimicked the effect of inoculation, and the addition of an inhibitor of its synthesis or of its physiological activity completely blocked A. brasilense growth promotion. Based on our results, we propose that the process of growth promotion triggered by A. brasilense inoculation involves a signaling pathway that has ethylene as a central, positive regulator.A. brasilense growth promotion. Based on our results, we propose that the process of growth promotion triggered by A. brasilense inoculation involves a signaling pathway that has ethylene as a central, positive regulator.growth promotion. Based on our results, we propose that the process of growth promotion triggered by A. brasilense inoculation involves a signaling pathway that has ethylene as a central, positive regulator.A. brasilense inoculation involves a signaling pathway that has ethylene as a central, positive regulator. Key words: ACS; auxins; Azospirillum sp.; ethylene; IAA; Lycopersicon esculentum; plant growth promotion.ACS; auxins; Azospirillum sp.; ethylene; IAA; Lycopersicon esculentum; plant growth promotion.Lycopersicon esculentum; plant growth promotion. Fil: Ribaudo, Claudia Mónica. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Krumpholz, Evelyn M.. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Cassan, Fabricio Dario. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular. Laboratorio de Fisiología Vegetal; Argentina. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales. Instituto de Investigaciones Agrobiotecnologicas. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto de Investigaciones Agrobiotecnologicas.; Argentina Fil: Bottini, Ambrosio Rubén. Universidad Nacional de Río Cuarto; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina Fil: Cantore, Maria Leonor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales. Grupo Vinculado Centro de Estudios de Biodiversidad y Biotecnología MdP- INBA; Argentina Fil: Curá, José Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales. Grupo Vinculado Centro de Estudios de Biodiversidad y Biotecnología MdP- INBA; Argentina

Amyloses from selected corn starches were used to measure the glucoses involved in the branching points. The number of glucose α 1,6 glycosidically linked were determined by two different methods: 1) The enzymatic one measures directly quantiatively and specifically the glucoses α, 1,6 linked. 2) The other, a chemical one that measures the different n-methylated glucoses involved in the terminal, α 1,4 linked and α1,6 linked positions. The results obtained through both methodologies clearly indicate a good correlation. Amylose is not linear. It has very small proportion of branches and they are α1,6 glycosidically linked. Amylose ist nicht strikt linear. Amylosen von ausgewahlten Maisstarken wurden zur Messung der in Verzweigungspunkten enthaltenen Glucosen verwendet. Die Anzahl an Glucosen, die α-1,6-glykosidisch vernetzt waren, wurde durch zwei verschiedene Methoden bestimmt: 1) Die enzymatischen mist direkt quantitativ und spezifisch die α-1,6-verbundenen Glucosen, 2) die andere, eine chemische Methode, bestimmt die verschiedenen n-methylierten Glucosen, involviert in den therminulen α-1,4- und α-1,6-gebundenen Positionen. Die durch beide Methodologien erhaltenen Ergebnisse weisen eindeutig eine gute Korrelation auf. Amylose ist nicht linear. Sie hat einen geringen Anteil an Verzweigungen, und diese sind α-1,6-glysidisch verbunden.