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Previous studies showed that in vitro digestibility of proteins in cooked beans is modulated by heat treatment and that the effect may be different whether proteins are heated in intact cotyledon or in a bean flour. In this study, germinated and non-germinated soybean cotyledons and flour were boiled at 100 °C for varying times (30, 90, or 180 min). After grinding, the level of trypsin inhibitors, protein aggregation, surface hydrophobicity, the secondary structure, and in vitro digestibility were studied. The presence of an intact cell wall during cooking increased protein denaturation temperature by about 10% and reduced the denaturation of trypsin inhibitors, and induced distinct changes in protein surface hydrophobicity and secondary structure. These physicochemical properties translated into an increment in protein degree of hydrolysis (DH, 72%) of protein cooked for 30 min as flour compared to proteins cooked in intact soybean tissues (64%). Increase in cooking times (90 and 180 min) resulted in limited improvement in the protein digestibility and changes in protein physicochemical properties for both boiled cotyledons and flour. Soybean germination resulted in distinct changes in protein physicochemical properties and higher protein DH% of raw soybean (61%) compared to non-germinated raw soybean (36%). An increase in protein digestibility of germinated soybean was also observed after boiling for both cotyledon and flour. However, significant differences in DH% were not observed between proteins boiled in intact cotyledon and in a flour. This work provides extra knowledge of the role of cellular integrity on protein properties in plant foods and suggests that germination or grinding before cooking may increase protein digestibility.

Plants detect neighboring vegetation as potential competitors for resources. Vegetation proximity is perceived by changes in the red (R) to far-red (FR) ratio (R:FR) through the phytochrome photoreceptors. To face this challenge, many plants have evolved the strategy to avoid shade, displaying a series of responses known as the shade avoidance syndrome (SAS). The SAS responses have been mostly studied at the seedling stage, and cover hypocotyl elongation as well as cotyledon and primary leaf expansion. In adult stages, SAS responses include an increase in petiole elongation and a decrease in leaf expansion, and an increase in plant height. Thus, the analysis of these responses provides a valuable and simple way to study how vegetation proximity affects plant development in both seedlings and adult plants. Here we describe a simple protocol to simulate shade in the laboratory and to evaluate these responses. Overall, our protocol can be easily used to expand the set of SAS responses of plants at different stages of development.

Plants detect neighboring vegetation as potential competitors for resources. Vegetation proximity is perceived by changes in the red (R) to far-red (FR) ratio (R:FR) through the phytochrome photorecep-tors. To face this challenge, many plants have evolved the strategy to avoid shade, displaying a series of responses known as the shade avoidance syndrome (SAS). The SAS responses have been mostly studied at the seedling stage, and cover hypocotyl elongation as well as cotyledon and primary leaf expansion. In adult stages, SAS responses include an increase in petiole elongation and a decrease in leaf expansion, and an increase in plant height. Thus, the analysis of these responses provides a valuable and simple way to study how vegetation proximity affects plant development in both seedlings and adult plants. Here we describe a simple protocol to simulate shade in the laboratory and to evaluate these responses. Overall, our protocol can be easily used to expand the set of SAS responses of plants at different stages of development., Postprint (published version)

A total of 48 Katahdin x Pelibuey multiparous ewes were used to evaluate the effect of nutritional restriction (40 %) before (30 d, RT), after (50 d, TR) or both periods (80 d, RR) compared with a control group on maternal body status, early fetal growth and lamb birth weights. Only twin bearing ewes were selected at d 50 of pregnancy for fetal measurements by ultrasonography and record of birth weight. Compared with control ewes, lower (p < 0.05) weight and body condition score had RT and RR ewes at mating time, likewise, TR and RR ewes at d 50 post-conception. There were mainly differences between fetuses from control and RT ewes, being higher (p < 0.05) the vesicular, abdominal and fetal area, as well as crown-rump length and birth weight for RT fetuses. In conclusión, preconception undernutrition positively altered the early fetal growth and lamb birth weights in hair ewes pregnant with twins., Se usaron 48 ovejas multíparas Katahdin x Pelibuey para evaluar el efecto del 40 % de restricción nutricional antes (30 d, RT), después (50 d, TR) o antes y después de la concepción (80 d, RR), comparado con un grupo testigo sobre el estado corporal materno, crecimiento fetal temprano y peso al nacimiento de las crías. Solo ovejas con preñez gemelar fueron seleccionadas al día 50 post-monta para mediciones fetales por ultrasonografía y registro de peso al nacimiento. Las ovejas RT y RR tuvieron menor (p < 0.05) peso y condición corporal al empadre, mientras que las ovejas TR y RR a los 50 días post-concepción tuvieron menor peso que las ovejas de los otros tratamientos. Se observaron diferencias entre fetos de ovejas testigo y RT, siendo mayor (p < 0.05) el área vesicular, abdominal y fetal, además de la longitud cráneo-caudal y los pesos al nacimiento en fetos de ovejas RT. La desnutrición pre-concepción alteró de forma positiva el crecimiento fetal temprano y el peso al nacimiento de las crías en ovejas de pelo con preñez gemelar.

A total of 48 Katahdin x Pelibuey multiparous ewes were used to evaluate the effect of nutritional restriction (40 %) before (30 d, RT), after (50 d, TR) or both periods (80 d, RR) compared with a control group on maternal body status, early fetal growth and lamb birth weights. Only twin bearing ewes were selected at d 50 of pregnancy for fetal measurements by ultrasonography and record of birth weight. Compared with control ewes, lower (p < 0.05) weight and body condition score had RT and RR ewes at mating time, likewise, TR and RR ewes at d 50 post-conception. There were mainly differences between fetuses from control and RT ewes, being higher (p < 0.05) the vesicular, abdominal and fetal area, as well as crown-rump length and birth weight for RT fetuses. In conclusión, preconception undernutrition positively altered the early fetal growth and lamb birth weights in hair ewes pregnant with twins., Se usaron 48 ovejas multíparas Katahdin x Pelibuey para evaluar el efecto del 40 % de restricción nutricional antes (30 d, RT), después (50 d, TR) o antes y después de la concepción (80 d, RR), comparado con un grupo testigo sobre el estado corporal materno, crecimiento fetal temprano y peso al nacimiento de las crías. Solo ovejas con preñez gemelar fueron seleccionadas al día 50 post-monta para mediciones fetales por ultrasonografía y registro de peso al nacimiento. Las ovejas RT y RR tuvieron menor (p < 0.05) peso y condición corporal al empadre, mientras que las ovejas TR y RR a los 50 días post-concepción tuvieron menor peso que las ovejas de los otros tratamientos. Se observaron diferencias entre fetos de ovejas testigo y RT, siendo mayor (p < 0.05) el área vesicular, abdominal y fetal, además de la longitud cráneo-caudal y los pesos al nacimiento en fetos de ovejas RT. La desnutrición pre-concepción alteró de forma positiva el crecimiento fetal temprano y el peso al nacimiento de las crías en ovejas de pelo con preñez gemelar.

Much of our current knowledge about seed development and differentiation regarding reserves synthesis and accumulation come from monocot (cereals) plants. Studies in dicotyledonous seeds differentiation are limited to a few species and in oleaginous species are even scarcer despite their agronomic and economic importance. We examined the changes accompanying the differentiation of olive endosperm and cotyledon with a focus on protein bodies (PBs) biogenesis during legumin protein synthesis and accumulation, with the aim of getting insights and a better understanding of the PBs’ formation process. Cotyledon and endosperm undergo differentiation during seed development, where an asynchronous time-course of protein synthesis, accumulation, and differential PB formation patterns was found in both tissues. At the end of seed maturation, a broad population of PBs, particularly in cotyledon cells, was distinguishable in terms of number per cell and morphometric and cytochemical features. Olive seed development is a tissue-dependent process characterized by differential rates of legumin accumulation and PB formation in the main tissues integrating seed. One of the main features of the impressive differentiation process is the specific formation of a broad group of PBs, particularly in cotyledon cells, which might depend on selective accumulation and packaging of proteins and specific polypeptides into PBs. The nature and availability of the major components detected in the PBs of olive seed are key parameters in order to consider the potential use of this material as a suitable source of carbon and nitrogen for animal or even human use.

Seeds are a source of organic (carbon, C) and mineral (nitrogen, N and phosphorus, P) nutrients for the growing seedling. There is much information on seed mass and N and P contents, and the relationship between these and seedling mass. Within the world’s temperate regions, these collectively show that N and P concentrations remain constant or rise with increase in seed mass and that seeds are larger and more nutrient-enriched in poorer soils. Seed N and P were more important than seed C in accounting for seedling mass in 85% of studies we assessed. In nutrient- and water-limited environments that are not light-limited, large seeds routinely provision the seedling with N and P that enhance C-fixation and thus general growth in the first wet season. This system is so efficient that growth response to soil nutrients may be negligible in first-year seedlings arising from seeds > 15 mg mass, N content > 5 mg and P content > 1.6 mg. The elongating taproot system absorbs nutrients and maintains water uptake as soil water retreats, enhancing the chances of survival in the first dry season. We outline an interpretative scenario for the special role of large seeds (>15 mg) in nutrient- and water-limited environments that recognizes the critical role of N and P for photosynthesis in ensuring sufficient C-supply to the rapidly descending roots for effective drought-avoidance by the young plant.

Reorganization and degradation of the wall crosslinking and seed storage polysaccharide xyloglucan by glycoside hydrolase family 16 (GH16) endo-transglycosylases and hydrolases are crucial to the growth of the majority of land plants, affecting processes as diverse as germination, morphogenesis, and fruit ripening. A high-resolution, three-dimensional structure of a nasturtium (Tropaeolum majus) endo-xyloglucanase loop mutant, TmNXG1-Delta YNIIG, with an ohgosaccharide product bound in the negative active-site subsites, has been solved by X-ray crystallography. Comparison of this novel complex to that of the strict xyloglucan endotransglycosylase PttXET16-34 from hybrid aspen (Populus tremula x tremuloides), previously solved with a xylogluco-oligosaccharide bound in the positive subsites, highlighted key protein structures that affect the disparate catalytic activities displayed by these closely related enzymes. Combination of these "partial" active-site complexes through molecular dynamics simulations in water allowed modeling of wild-type TmNXG1, TmNXG1-Delta YNIIG, and wild-type PttXET16-34 in complex with a xyloglucan octadecasaccharide spanning the entire catalytic cleft. A comprehensive analysis of these full-length complexes underscored the importance of various loops lining the active site. Subtle differences leading to a tighter hydrogen bonding pattern on the negative (glycosyl donor) binding subsites, together with loop flexibility on the positive (glycosyl acceptor) binding subsites appear to favor hydrolysis over transglycosylation in GH16 xyloglucan-active enzymes., QC 20100902

Faba beans cv. Fiesta with seed moisture content (SMC) modified to 8, 10, 12 and 14% were packed in polyethylene lined aluminium foil bags and stored at 5, 15, 20, 25, 30, 37, 45, 50 or 60 C ( 2 C) for one year. Samples were analysed for moisture content and seed coat (testa) colour over the storage period using a chroma meter. A continuous increase in L* and b* values was found in all samples with the passage of time whereas a *values first increased and then decreased in samples stored at relatively high temperatures (= 37 C). The initial beige testa colour changed to light brown, dark reddish brown or almost black depending on storage conditions. The higher the temperature and SMC the faster the rate of change in colour (E ab* values). Seeds with 8% SMC had more stable testa colour compared to seeds with higher SMC. Exposure to artificial light (350 mol m -2 s -1) substantially accelerated the colour darkening. Cotyledon stored at 37+2 C also darkened with the storage time. A loss in total free phenolics, total tannins and proanthocyanidins was found with increased darkness of testa and cotyledons during storage.

This work presents the preliminary results of in vitro studies with Araujia sericifera, which is cultivated for ornamental purposes. Immature seeds from wild plants were used to start the cultures. Somatic embryos and friable embryogenic calluses were obtained from white cotyledons in media containing naphthaleneacetic acid and benzyladenine or 2,4-dichlorophenoxyacetic acid. Plants were regenerated from these somatic embryos. Cell suspensions obtained from friable calluses cultured in M1 modified medium showed a considerable growth capacity. The packed cell volume was doubled in about 15 days of culture at the exponential phase. the results obtained may be used to design further experiments with the aim of improving somatic embryogenesis.

Published in: Plant Physiol, vol. 85, 1987.

Published in: Madrono, Vol. 48, No. 3, 2001.

Published in: Plant Physiology, vol. 76, no.3, 1984.

Published in: Plant Physiology, vol. 76, no.3, 1984.

Published in: Plant Physiol, vol. 85, 1987.

Published in: Madrono, Vol. 48, No. 3, 2001.

Brassica napus is a commercially important crop worldwide and its use is quickly increasing due to its beneficial oil products and biofuel demands. Yield can be lost through infection by a fungal pathogen, Leptosphaeria maculans, the causal agent of stem canker (blackleg). An early indication of the presence of stem canker is a lesion (leaf spot) on the cotyledons or early leaves. The leaf spot stage of the disease was used in this work to ascertain if biological control agents applied both individually and in combination decreased the lesion area and also to quantify the amount of L. maculans DNA present using quantitative polymerase chain reaction (qPCR). The natural production of antibiotics by some bacteria is a commonly found form of antagonistic biological control. Bacillus amyloliquefaciens and Pseudomonas chlororaphis spp. aureofaciens 30.84 evaluated in this work both produce antibiotics and were assayed for their ability to provide control of Leptosphaeria maculans. Known active strains and field isolates of Bacillus and Pseudomonas were tested as potential biocontrol agents in vitro and then used in in planta assays. The in planta assays using bacterial isolates applied individually indicated that all the bacteria gave statistically significant control of L. maculans at the leaf spot stage. Those isolates with highest activity were further evaluated in combination, to determine if improved control of leaf spot occurred. Firstly, however, it was important to confirm the two bacteria would be compatible and antibiotics would be produced. To this aim, an in vitro assay using mutant Chromobacterium violaceum confirmed Pseudomonas chlororaphis spp. aureofaciens upregulated antibiotic production using acyl-homoserine lactones, signalling molecules. Consequently, it was vital that the Bacillus applied with it did not produce lactonase which would denature these molecules. PCR was used to confirm the enzyme was not present. It was, however, shown using in planta