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Water soaking is a commercially important disorder of field-grown strawberries that is exacerbated by surface wetness and high humidity. The objective was to establish the effect of genotype on susceptibility to water soaking. Three greenhouse-grown model 'collections' were used comprising a total of 172 different genotypes: (1) a segregating F2 population, (2) a collection of strawberry cultivars and breeding clones, and (3) a collection of wild Fragaria species. A standardized immersion assay was used to induce water soaking. Potential relationships between water soaking and water uptake characteristics, depth of the achene depressions, fruit firmness, cuticle mass and strain relaxation and microcracking were investigated. Further, the effect of downregulating the polygalacturonase genes (FaPG1 and FaPG2) on the susceptibility to water soaking was investigated. The collection of wild species was most susceptible to water soaking. This was followed by the collection of cultivars and breeding clones, and by the F2 population. Susceptibility to water soaking was strongly correlated with water uptake rate (mass of water, per fruit, per time). For the pooled dataset of 172 genotypes, 46% of the variability in water soaking was accounted for by the permeance of the skin to osmotic water uptake. Susceptibility to water soaking was not, or was only poorly correlated with measurements of fruit surface area or of the osmotic potential of the expressed fruit juice. The only exceptions were the wild Fragaria species which were highly variable in fruit size and also in fruit osmotic potential. For genotypes from the F2 and the wild species collections, firmer fruit were less susceptible to water soaking than softer fruit. There were no relationships between fruit firmness and susceptibility to water soaking in transgenic plants in which FaPG1 and FaPG2 were down-regulated. Susceptibility to water soaking was not related to cuticle mass per unit fruit surface area, nor to strain relaxation of the cuticle upon isolation, nor to achene position. In summary, strawberry's susceptibility to water soaking has a significant genetic component and is closely and consistently related to the skin's permeance to osmotic water uptake. [ABSTRACT FROM AUTHOR]

Water soaking is a commercially important disorder of field-grown strawberries that is exacerbated by surface wetness and high humidity. The objective was to establish the effect of genotype on susceptibility to water soaking. Three greenhouse-grown model ‘collections’ were used comprising a total of 172 different genotypes: (1) a segregating F2 population, (2) a collection of strawberry cultivars and breeding clones, and (3) a collection of wild Fragaria species. A standardized immersion assay was used to induce water soaking. Potential relationships between water soaking and water uptake characteristics, depth of the achene depressions, fruit firmness, cuticle mass and strain relaxation and microcracking were investigated. Further, the effect of downregulating the polygalacturonase genes (FaPG1 and FaPG2) on the susceptibility to water soaking was investigated. The collection of wild species was most susceptible to water soaking. This was followed by the collection of cultivars and breeding clones, and by the F2 population. Susceptibility to water soaking was strongly correlated with water uptake rate (mass of water, per fruit, per time). For the pooled dataset of 172 genotypes, 46% of the variability in water soaking was accounted for by the permeance of the skin to osmotic water uptake. Susceptibility to water soaking was not, or was only poorly correlated with measurements of fruit surface area or of the osmotic potential of the expressed fruit juice. The only exceptions were the wild Fragaria species which were highly variable in fruit size and also in fruit osmotic potential. For genotypes from the F2 and the wild species collections, firmer fruit were less susceptible to water soaking than softer fruit. There were no relationships between fruit firmness and susceptibility to water soaking in transgenic plants in which FaPG1 and FaPG2 were down-regulated. Susceptibility to water soaking was not related to cuticle mass per unit fruit surface area, nor to strain relaxation of the cuticle upon isolation, nor to achene position. In summary, strawberry’s susceptibility to water soaking has a significant genetic component and is closely and consistently related to the skin’s permeance to osmotic water uptake.

Plantago ovata Forssk. is an emerging crop yielding psyllium husk, a material comprised of hydrophilic polysaccharides that form mucilage upon wetting. Psyllium husk has important industrial uses including as a dietary fibre supplement and a textural alternative in gluten‐free bread production. Industrial applications require high‐quality and purity psyllium husk, but consistent supply of uniform quality material is often limited by climatic constraints, especially unseasonable rainfall at crop maturity. Here we compared the seed quality of four P. ovata varieties harvested before and after 26 mm of rain and validated our key findings in the following season. Colourimetry showed that the rain event caused the seeds to be darker and greener, possibly from pigment oxidation and microbial growth. Sugar profiling, water absorption assays and microscopy showed that premature hydration of the husk in rain‐damaged samples caused loss of the most soluble mucilage components and an increase in non‐mucilage contaminants, leading to a reduction in seed water absorption capacity, which is a key indicator of psyllium husk functionality. Germination was also diminished in rain‐affected seeds. In this study we show for the first time the extent that unseasonable rain at maturity has on P. ovata seed quality. We suggest that rain‐damaged seeds are unsuitable for husk production and resowing and outline potential screening methods to identify rain‐damaged seeds before purchase. Additionally, the extensive quality impacts described here may make P. ovata a suitable model or indicator species for studying acute climate effects on seed quality, especially from rain. [ABSTRACT FROM AUTHOR]

Water soaking is an important surface disorder of strawberries that limits unprotected field production. The objective was to identify the mechanism(s) of water soaking. Symptomatic fruit show pale, deliquescent patches of skin. This damage extends into the flesh. Numerous cuticular microcracks occurred in water-soaked areas. Water soaking occurred only if the skin was exposed to liquid water. Water soaking was more rapid when the cuticle had been abraded. Water soaking, anthocyanin leakage, and water uptake all increased with incubation time. There was a lag phase for water soaking and anthocyanin leakage, but not for water uptake. Susceptibility to water soaking increased with fruit ripening and mass. Incubation in isotonic PEG 6000 increased cuticular microcracking but decreased water soaking and water uptake. Incubation in hypotonic fruit juice (natural and artificial) increased water soaking incidence and severity but reduced water uptake. Incubation in dilute citric and malic acids increased plasma membrane permeability as indexed by anthocyanin leakage and increased water soaking. Thus, water soaking involves cuticular microcracking, localized water uptake, bursting of cells, and the release of organic acids into the apoplast. The damage propagates from cell to cell.

Water soaking is an important surface disorder of strawberries that limits unprotected field production. The objective was to identify the mechanism(s) of water soaking. Symptomatic fruit show pale, deliquescent patches of skin. This damage extends into the flesh. Numerous cuticular microcracks occurred in water-soaked areas. Water soaking occurred only if the skin was exposed to liquid water. Water soaking was more rapid when the cuticle had been abraded. Water soaking, anthocyanin leakage, and water uptake all increased with incubation time. There was a lag phase for water soaking and anthocyanin leakage, but not for water uptake. Susceptibility to water soaking increased with fruit ripening and mass. Incubation in isotonic PEG 6000 increased cuticular microcracking but decreased water soaking and water uptake. Incubation in hypotonic fruit juice (natural and artificial) increased water soaking incidence and severity but reduced water uptake. Incubation in dilute citric and malic acids increased plasma membrane permeability as indexed by anthocyanin leakage and increased water soaking. Thus, water soaking involves cuticular microcracking, localized water uptake, bursting of cells, and the release of organic acids into the apoplast. The damage propagates from cell to cell. [ABSTRACT FROM AUTHOR]

Productivity in strawberry (Fragaria × ananassa) can be recorded by measuring marketable or total yield. The first objective of this review was to determine if marketable yield can be predicted from total yield. The second objective of this review was to develop protocols to accurately determine the productivity of strawberry cultivars. Previous research has not examined the relationship between the two measures of productivity and how to best measure the yield of strawberry cultivars. The relationship between marketable and total yield was assessed by examining the performance of strawberry cultivars across 68 studies. Marketable yield had a linear, but inconsistent relationship with total yield across different cultivars, sites and years. The slope from the regression between marketable and total yield ranged from 0.25 to 0.99, with a median of 0.80, and a mean (and SE) of 0.78 ± 0.01. Marketable yield cannot be predicted from total yield. The results of this review demonstrate that marketable yield is a better indicator of productivity than total yield. Both measures of productivity should be used in future cultivar studies. The results also demonstrate that cultivar experiments that include information on the incidence of fruit defects are better than ones that do not. [ABSTRACT FROM AUTHOR]

Spider orb webs have evolved to stop flying prey, fast and slow alike. One of the main web elements dissipating impact energy is the radial fibers, or major ampullate silks, which possess a toughness surpassing most man-made materials. Orb webs are extended phenotypes, and as such their architectural elements, including major ampullate silks, have been selected to optimize prey capture under the respective environmental conditions. In this study, we investigated the correlation of three landscape scales and three microhabitat characteristics with intrinsic silk properties (elastic modulus, yield stress, tensile strength, extensibility, and toughness) to understand underlying ecological patterns. For this purpose, we collected and mechanically tested major ampullate silks from 50 spider species inhabiting large altitudinal and climatic gradients in Colombia. Using regression analysis and model selection, we investigated the environmental drivers of inter- and intra-specific patterns of major ampullate silk properties, taking into account phylogenetic relatedness based on newly sequenced mitochondrial genomes. We found that the total amount of energy absorbed, i.e., toughness and tensile strength, is higher for fibers from species inhabiting regions where heavy rainfall is common. Interestingly, we observe the same general trend between individuals of the same species, stressing the importance of this environmental driver. We also observe a phylogenetic conservation in the relation of environmental variables with silk tensile strength and yield stress. In conclusion, the increase in major ampullate silk tensile strength and toughness may reflect an adaptation to prevent frequent rain damage to orb webs and the associated energetic loss. • MAS toughness and strength are higher in regions with common heavy rainfall • The same rise in toughness was observed inter- and intra-specifically • Phylogenetic conservation was observed in several of the relationships This study investigates how the mechanical properties of major ampullate silks, i.e., spider orb web radii, correlate with environmental variables. Hopfe et al. find that silks are stronger and tougher in regions where heavy rainfall is more common, thus preventing frequent rain damage to orb webs and the associated energetic loss for spiders. [ABSTRACT FROM AUTHOR]

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The frustrations of forage producers attempting to conserve high-quality alfalfa (Medicago sativa L.) silage during periods of unstable or inclement weather are widely known. Our objectives for this series of studies were to (1) assess indicators of ensilability, such as pH, buffering capacity, water-soluble carbohydrates (WSC), and starch for wilting alfalfa forages receiving no rainfall or damaged by simulated or natural rainfall events; (2) use these data as inputs to calculate the threshold moisture concentration that would prohibit a clostridially dominated fermentation; and (3) further evaluate the effects of rain damage or no rain damage on measures of forage nutritive value. Rainfall events were applied to wilting forages by both simulated and natural methods over multiple studies distributed across 4 independent forage harvests. Generally, simulated rainfall was applied to alfalfa under controlled conditions in which forages were relatively wet at the time of application, and subsequently were dried to final moisture endpoints under near ideal conditions within a constant temperature/humidity environmental chamber, thereby limiting postwetting wilting time to =21 h. As a result, indicators of ensilability, as well as measures of nutritive value, changed only marginally as a result of treatment. Consistently, reductions in concentrations of WSC and starch occurred, but changes in WSC were relatively modest, and postwetting concentrations of WSC may have been buoyed by hydrolysis of starch. When forages were subjected to natural rainfall events followed by prolonged exposure under field conditions, indicators of ensilability were much less desirable. In one study in which alfalfa received 49.3 mm of natural rainfall over a prolonged (8-d) field-exposure period, fresh pH increased from 6.48 to 7.43 within all forages exposed to these extended, moist wilting conditions. Furthermore, sharp reductions were observed in buffering capacity (410 vs. 337 mEq/kg of DM), WSC (6.13 vs. 2.90%), starch (2.28 vs. 0.45%), and clostridially dominated fermentation (62.7 vs. 59.4%). Based on these experiments, the potential for good fermentation is affected only minimally by single rainfall events applied to relatively wet forages, provided these events are followed by rapid dehydration; however, attaining acceptable silage fermentations with forages subjected to prolonged exposure under poor drying conditions is likely to be far more problematic. [ABSTRACT FROM AUTHOR]

RESUMOO trigo na colheita está exposto a danos por chuva, que podem levar à alteração na qualidade e perda de valor comercial. O objetivo desse trabalho foi caracterizar as alterações de diferentes variedades de trigo da região Sul que sofreram danos por chuva, detectado pelo método de falling number. Treze amostras foram avaliadas quanto a peso hectolitro, peso de mil sementes, proteína, açúcares redutores, nitrogênio solúvel, nitrogênio de aminoácidos livres e atividade enzimática α e β-amilase, β-glucanase e protease). As alterações na fração de gliadina foram avaliadas por eletroforese SDS-PAGE. As variáveis açúcares redutores, nitrogênio solúvel, nitrogênio de aminoácidos livres, atividade de α-amilase, β-glucanase e protease apresentaram correlações significativas com falling number. À medida que houve redução do falling number, as gliadinas apresentaram alterações nas bandas entre 40 e 30 KDa que ficaram mais intensas.