Isoflavone Changes in Immature and Mature Soybeans by Thermal Processing

The isoflavone changes occurring in mature soybeans during food processing have been well studied, but less information is available on the changes in immature soybeans during thermal processing. This study aimed to determine the effect of thermal processing by dry- or wet-heating on the changes in the isoflavone profiles of immature and mature soybeans. In the malonylglycoside forms of isoflavone, their deglycosylation was more severe after wet-heating than after dry-heating regardless of the soybean maturity. The malonyl forms of isoflavones in the immature seeds were drastically degraded after a short wet-heating process. In the acetylglycoside forms of isoflavone, dry-heating produced relatively low amounts of the acetyl types in the immature soybeans compared with those in the mature soybeans. These results were explained by the content of acetyldaidzin being relatively less changed after dry-heating immature soybeans but increasing four to five times in the mature soybeans. More of the other types of acetylglycoside were produced by dry-heating soybeans regardless of their maturity. Acetylgenistin in wet-heating was a key molecule because its content was unchanged in the immature soybeans during processing but increased in the mature soybeans. This determined the total acetylglycoside content after wet-heating. In contrast, most of the acetyl forms of isoflavone were produced after 90 to 120 min of dry-heating regardless of the seed maturity. It can be suggested that the pattern of isoflavone conversion was significantly affected by the innate water content of the seeds, with a lower water content in the mature soybeans leading to the greater production of acetyl isoflavones regardless of the processing method even if only applied for a relatively short time. The results suggested that the isoflavone conversion in the immature soybeans mainly follows the wet-heating process and can be promoted in the application of stronger processing.

Morphological features of fruits, seeds and seedlings of Aerva lanata (L.) Juss. in the conditions of introduction to the Southern coast of the Crimea

The results of the study of the early stages of the ontogenesis of Aerva lanata (L.) Juss. in the conditions of introduction to the Southern coast of the Crimea are presented. Morphobiological signs of seeds, morphological features of fruits, seeds and seedlings were revealed. The fruit of A. lanata is a densely pubescent single-seeded box of a rounded shape from greenish to cream color. The morphometric parameters of the seeds have a very low level of variability (from 5 to 10%). On average, their length is 0.72 mm, width - 0.55 mm, and thickness - 0.40 mm. As a result of the research, the seeds were found to be of different quality. Immature seeds from red to dark brown are located mainly in the upper and middle part of the inflorescence. The marginal embryo is milky in color, covering the abundant perisperm in a semicircle, on average 1.55 mm in length and 0.16 mm in width. The seedlings are small lobe-shaped, petiolate light green 2 mm long and 1 mm wide. The hypocotyl is white 0.4 mm long. According to the method of distribution of diaspores, A. lanata refers to barochora plants. The coefficient of semenification was 36.2%.

Masting effect on alpha and beta avian diversity in fragmented forests of relict-endangered Mexican Beech (Fagus grandifolia subsp. mexicana)

Background Tropical montane cloud forests are one of the most important hotspots on Earth and show presence of relict-endemic and endangered species, representing about 14% of the total tropical forest worldwide. Synchronous seed production or masting in tropical montane cloud tree species is a widespread reproductive strategy of deciduous and evergreen broad-leaved tree associations to decrease costs of reproduction and ensure offspring. Masting event maintains a high avian diversity, which can be modified by phenological process (seed production and non-seed production). Methods The main aim of this study was to assess alpha and beta avian diversity and whether the composition of the trophic guild modifies among phenological processes and between two fragmented relict-endangered Mexican Beech (Fagus grandifolia subsp. mexicana) forests (Medio Monte and El Gosco) in the Mexican state of Hidalgo. In addition, we evaluated beechnut production. Results We recorded 36 bird species, 11 of them included in some conservation risk status, and 5 endemic species. Alpha diversity values were dissimilar in avian richness (q = 0) among phenological processes and between fragmented beech forests. Avian communities among three phenological processes and between fragmented forests were structurally similar, dominated during immature seeds the Brown-backed Solitaire (granivores–insectivores–frugivores); during mature seeds the White-crowned Parrot (Pionus senilis, granivores–frugivores); and the Dwarf Jay (Cyanolyca nana, insectivores) was abundant during low seed quality. The complementarity index was high among phenological processes and low between forests. We found a high bird turnover value between immature seeds—mature seeds and during mature seeds—low seed quality. Furthermore, a similar pattern was recorded between the two study forests. Seed production showed a high number of undamaged beechnuts in Medio Monte, while in El Gosco beechnuts were attacked by insects. Conclusions Our results reflect that masting phenological process and contrasting study forests’ structure influence the shifts in alpha and beta diversity of seed and non-seed bird consumers. Our study reaffirms the importance of continuing studies throughout masting in all the Mexican Beech forests to address regional efforts in preserving the relict-ecological interactions.

Alkaloid Distribution in Seeds of Argemone mexicana L. (Papaveraceae)

Seeds of Argemone mexicana L. accumulate significative amounts of sanguinarine. The analysis of the distribution of this alkaloid through the tissues of mature seeds revealed that up to 60 % of its contents was found tightly fixed to the different components of the seed external covers where it persisted during seedling germination. Contrastingly, sanguinarine contents in cotyledon accounted for the remaining 40 % and it could have been, at least partially, mobilized to the newly formed hypocotyls during emergence from seeds. Berberine was only detected in immature seeds and in seedlings once cotyledons were totally displayed. These results are discussed as a possible sanguinarine role in the chemical protection during seedlings germination. Resumen. Semillas de Argemone mexicana L. acumulan cantidades elevadas de sanguinarina. Un análisis de la distribución de alcaloides en los diferentes tejidos que componen la semilla reveló que hasta un 60 % del contenido se encontraba fuertemente unido en las capas que forman la cubierta exterior, donde se retuvieron durante la emergencia del hipocótilo. En contraste, los cotiledones presentaron el 40 % restante y parte de ello pudo haber sido movilizado al hipocótilo al emerger. Berberina sólo se observó en semillas inmaduras y en plántulas en desarrollo con los cotiledones desplegados. Estos resultados se discuten en función del posible papel defensivo de la sanguinarina durante la germinación.

Morphophysiology and Cryopreservation of Seeds of Dendrobium Nobile Lindl. (Orchidaceae) at Different Stages of Development

We studied the seed maturation of Dendrobium nobile Lindl to establish the optimal stage for green pod culture and long-term storage in liquid nitrogen. It was found that the immature seeds can germinate in vitro starting from 3 months after pollination (MAP) but only develop up to the stage of embryo swelling or protocorm without rhizoids. The maximum staining of embryos with vital dyes FDA and TTC occurs at 4 and 5 MAP that corresponds to the release of suspensor beyond the embryo sac. Embryo staining does not correlate with germination capacity and seed viability in cryogenic storage. The immature seeds acquire resistance to freezing and drying in airflow at the age of 6 MAP. The time of technical maturity for green pod culture and cryopreservation may be reduced from 12 MAP to 6–7 MAP.

The primary cause for the development of bacterial blight of seeds in soybean and other leguminous crops

One of the significant reasons for the decrease in the sowing quality of seeds in leguminous crops all over the world is bacterial blight of seeds in the form of necrotic decaying spots on the outer or inner side of the cotyledons. A hypothesis was put forward about the presence of a common primary non-bacterial cause of the development of necrosis on cotyledons, regardless of the species, variety and growing zone. The studies were carried out in 2016– 2020 in V.S. Pustovoit All-Russian Research Institute of Oil Crops, Krasnodar, on seeds of soybeans, common bean, chickpea, white and narrow-leaved lupines. On immature seeds of healthy soybean plants in the phases of full filling and the beginning of physiological maturation, bacterial blight of seeds are never observed. Secondary (rain) moistening of mature seeds leads to the development of cotyledon necrosis and a decrease in their germination in soybeans, common beans, chickpeas, white lupine and narrow-leaved lupine. The physiological reason for the formation of cotyledon necrosis during the secondary moistening of mature seeds is the death of the tissues of the cotyledons, moistened before the stage of nucleic acid synthesis, and unable to return to the dormant stage upon repeated drying. Symptoms of the development of cotyledon necrosis after secondary moistening of mature seeds, and bacterial blight of seeds, are practically identical in all leguminous crops. The common primary cause of the formation of necrotic spots on the surface of the cotyledons, identified as bacterial blight of seeds, regardless of the species of legumes, variety and ecological-geographical zone of cultivation, is the secondary (rain) moisture of seeds that have not yet been harvested in the field of mature plants. Isolation of bacterial pathogens of various species and families in necrotic areas of the cotyledons can be explained by secondary infection of already dead tissues. Therefore, the species composition of bacterial microflora in each case will be determined by its presence in the environment.

Asymbiotic germination of Vanilla planifolia in relation to the timing of seed collection and seed pretreatments

Background Vanilla planifolia is an important tropical orchid for production of natural vanilla flavor. Traditionally, V. planifolia is propagated by stem cuttings, which produces identical genotype that are sensitive to virulent pathogens. However, propagation with seed germination of V. planifolia is intricate and unstable because the seed coat is extremely hard with strong hydrophobic nature. A better understanding of seed development, especially the formation of impermeable seed coat would provide insights into seed propagation and conservation of genetic resources of Vanilla. Results We found that soaking mature seeds in 4% sodium hypochlorite solution from 75 to 90 min significantly increased germination. For the culture of immature seeds, the seed collection at 45 days after pollination (DAP) had the highest germination percentage. We then investigated the anatomical features during seed development that associated with the effect of seed pretreatment on raising seed germination percentage. The 45-DAP immature seeds have developed globular embryos and the thickened non-lignified cell wall at the outermost layer of the outer seed coat. Seeds at 60 DAP and subsequent stages germinated poorly. As the seed approached maturity, the cell wall of the outermost layer of the outer seed coat became lignified and finally compressed into a thick envelope at maturity. On toluidine blue O staining, the wall of outer seed coat stained greenish blue, indicating the presence of phenolic compounds. As well, on Nile red staining, a cuticular substance was detected in the surface wall of the embryo proper and the innermost wall of the inner seed coat. Conclusion We report a reliable protocol for seed pretreatment of mature seeds and for immature seeds culture based on a defined time schedule of V. plantifolia seed development. The window for successful germination of culturing immature seed was short. The quick accumulation of lignin, phenolics and/or phytomelanins in the seed coat may seriously inhibit seed germination after 45 DAP. As seeds matured, the thickened and lignified seed coat formed an impermeable envelope surrounding the embryo, which may play an important role in inducing dormancy. Further studies covering different maturity of green capsules are required to understand the optimal seed maturity and germination of seeds.

Quality of Immature and Mature Pepper (Capsicum annuum L.) Seeds in Relation to Bio-Priming with Endophytic Pseudomonas and Bacillus spp.

Fruit maturity for seed production can occur at various times because of the continual flowering of pepper plants. Accordingly, seeds with different maturity are acquired as the fruits are collected in a single harvest. Immature seeds obtained in this harvest may lead to a decrease in the quality of seed lots. Therefore, this research aimed to evaluate the influence of four different endophytic bacteria strains (Pseudomonas fluorescens strain L5b, Pseudomonas gessardii strain L13, Bacillus subtilis strain Bs1 and Bacillus mojavensis strain ApBm) on germination and seedling vigor of immature and mature bell pepper seeds. To obtain seeds with different maturity levels, fruits were collected 45–49 days after flowering for immature seeds and 65–69 days for mature seeds. The effectiveness of these bacteria strains was examined by coating seeds with four different endophytic bacteria strains separately. Additionally, to see the activity of endophytic bacteria more clearly, a mock treatment with sterile water was added to the experiment as a control (+) group. Bio-priming (especially strain Bs1 and L13) improved germination and seedling emergence characteristics of both immature and mature seed lots compared to control groups (p < 0.05). The results demonstrate that bio-priming with beneficial endophytic bacteria can be used to stimulate the quality of both immature and mature seeds from the pepper.

How Carbon Source and Seedcoat Influence the In Vitro Culture of Peach (Prunus persica L. Batsch) Immature Seeds

The effects of carbon source and concentration and of seedcoat were tested on the in vitro germination of peach seeds derived from crosses performed in the field. Seeds were extracted from the fruit and cultured in Woody Plant Medium (WPM) supplemented with sucrose, glucose, or sorbitol at concentrations of 15, 30, and 45 g·L−1. The percentage of germination as well as the root and hypocotyl lengths were measured after the stratification process and before acclimatization. Seedcoat did not have any influence on seed germination in any tested media and genotype. Glucose at a concentration of 15 g·L−1 and sucrose at 15, 30, and 45 g·L−1 resulted in greater stem seedling growth. The root developed the most when seeds were cultured in media with 15 or 30 g·L−1 of sucrose.

Asymbiotic Germination of Mature Seeds and the Seed Development of Vanilla Planifolia

Background: Vanilla planifolia is an important tropical orchid for production of natural vanilla flavor. Traditionally, V. planifolia is propagated by stem cuttings, which produces identical genotype that are sensitive to virulent pathogens. However, sexual propagation with seed germination of V. planifolia is intricate and unstable because of the extremely hard seed coat. A better understanding of seed development, especially the formation of impermeable seed coat would provide insights into seed propagation and conservation of genetic resources of Vanilla.Results: We found that soaking mature seeds in 4 % sodium hypochlorite solution from 75 to 90 min significantly increased germination and that immature seeds collected at 45 days after pollination (DAP) had the highest germination percentage. We then investigated the anatomical features during seed development that associated with the effect of seed pretreatment on raising seed germination percentage. The 45-DAP immature seeds have developed globular embryos and the thickened non-lignified cell wall at the outermost layer of the outer seed coat. After 60 DAP, the cell wall of the outermost layer of the outer seed coat became lignified and finally compressed into a thick envelope. These features matches the significant decreases of immature seed germination percentage after 60 DAP. Conclusion: We report a reliable protocol for seed pretreatment of mature seeds and for immature seeds culture based on a defined time schedule of V. plantifolia seed development. The thickened and lignified seed coat formed an impermeable envelope surrounding the embryo, and might play an important role in seed dormancy of V. plantifolia.