Changes in chemical composition during development of grass pea (Lathyrus sativusL.) seeds

Forage yields and nutritive values of oat and triticale pastures for grazing sheep in early spring

Background

Small-grain winter cereals can be utilized as early spring pastures in temperate climates to relieve grazing pressure and potentially mitigate feed shortages. This study was conducted to determine the effects of triticale and oat cereal pastures grazed by sheep during early spring on forage yields, nutritive values, and nutritional requirements of sheep.

Methods

The research was carried out over three consecutive years, from 2015 to 2017, at the Sheep Research Institute in Bandırma-Balıkesir, located in the Marmara region of Türkiye. The treatments were arranged in a completely randomized block design, with the two forage species, triticale and oat, randomized within each of three blocks. The animal material for the study consisted of 24 Karacabey Merino sheep, each 2 years old, with an average live weight of 57.6 ± 0.5 kg, all in the late lactation stage. In each replication, four sheep were included, resulting in a total of 12 sheep grazing in each of the triticale and oat pastures. The sheep grazed exclusively on the cereal pastures without any additional feed, and had unrestricted access to water throughout the entire period of the experiment. The dry matter yields (DMY), dry matter intakes (DMI), nutritive values, and mineral contents of the cereal species were determined.

Results

The DMY showed significant differences over the years (P < 0.05). No differences in DMY were observed between pastures, with oats yielding 11.99 t ha-1 and triticale yielding 11.08 t ha-1. During the grazing period, the change in DMY was significant in all years (P < 0.05). The average DMI of the sheep was 2,003.5 g d-1 for triticale and 2,156.6 g d-1 for oat, respectively, and DMI exhibited no significant differences across pastures. Although there was no difference in DMI between 2015 and 2016, the lowest consumption occurred in 2017 (P < 0.05). Additionally, while DMI showed different trends each year based on the periods, it generally decreased by the end of the grazing period. While both pastures provided similar nutritive values, significant differences were observed in the crude protein (CP), acid detergent fiber (ADF), in vitro true DM digestibility (DDM), and metabolisable energy (ME) values across the years. Over the years, as the grazing period progressed, CP levels decreased while neutral detergent fiber (NDF), ADF, and acid detergent lignin (ADL) increased, resulting in reduced DDM and ME values. The phosphorus (P) content in triticale was higher than in oats, but there were no differences in the content of other minerals between them. Between the years, significant differences were observed in the levels of phosphorus (P) and iron (Fe), while changes in other elements were insignificant. The variation in mineral content during the grazing process differed over the three years. Study results indicated that the nutritional values of triticale and oat pastures are similar, and both can effectively be used to provide sufficient feed to meet the early spring forage requirements for sheep.

Analysis of Elymus nutans seed coat development elucidates the genetic basis of metabolome and transcriptome underlying seed coat permeability characteristics

The seed coat takes an important function in the life cycle of plants, especially seed growth and development. It promotes the accumulation of nutrients inside the seed and protects the seed embryo from mechanical damage. Seed coat permeability is an important characteristic of seeds, which not only affects seed germination, but also hinders the detection of seed vigor by electrical conductivity (EC) method. This research aimed to elucidate the mechanism of seed coat permeability formation through metabolome and transcriptome analysis of Elymus nutans. We collected the samples at 8, 18, and 28 days post-anthesis (dpa), and conducted a seed inclusion exosmosis experiment and observed the seed coat permeability. Moreover, we analyzed the changes in the metabolome and transcriptome during different development stages. Here, taking 8 dpa as control, 252 upregulated and 157 downregulated differentially expressed metabolites (DEMs) were observed and 886 upregulated unigenes and 1170 downregulated unigenes were identified at 18 dpa, while 4907 upregulated unigenes and 8561 downregulated unigenes were identified at 28 dpa. Meanwhile, we observed the components of ABC transporters, the biosynthesis of unsaturated fatty acids, and phenylalanine metabolism pathways. The key metabolites and genes affecting seed coat permeability were thiamine and salicylic acid. Furthermore, there were 13 and 14 genes with correlation coefficients greater than 0.8 with two key metabolites, respectively, and the -log₂Fold Change- of these genes were greater than 1 at different development stages. Meanwhile, pathogenesis-related protein 1 and phenylalanine ammonia-lyase play an important role in regulating the formation of compounds. Our results outline a framework for understanding the development changes during seed growth of E. nutans and provide insights into the traits of seed coat permeability and supply a great significance value to seed production and quality evaluation.

Effect of blend moisture and extrusion temperature on physical properties of everlasting pea-wheat extrudates

The effect of everlasting pea in combination with wheat on physical properties and microstructure of extrudates were studied. The share of everlasting pea (Lathyrus sativus) was variable, at 35, 50 and 65 %, respectively. The everlasting pea-wheat mixtures were moistened to the required level (18, 21, and 24 %), homogenized, conditioned and extruded in twin-screw extruder with counter-rotating conical screws. All of the obtained extrudates were characterised by a slow degree of radial expansion and high specific density. The Pearson correlation analysis indicated a statistically significant linear Pearson correlation (p < 0.05) between chemical compositions of the blends and physical properties of the extrudates. The expansion ratio increased as the concentration of the fibers and proteins increased, while specific density and hardness decreased. Inverse relationship was observed for crude fat. The microstructure of the extrudates was determined by both the moisture of the blend and the process temperature. The differences observed in the size, number of air cells and in the cell wall shapes and thickness indicate possibilities of the modification of physical properties of everlasting pea-wheat extrudates. The extrudates produced from everlasting pea-wheat blends (50:50) at higher barrel temperature (110/140/180/170/130 °C) were characterised by more numerous air cells of smaller diameters. Increasing moisture content of extruded blends results in extrudates with a higher porosity. No significant effect was shown in the chemical compositions on the level of metal contamination in the extrudates. The application of a counter-rotating twin-screw extrusion-cooker in the study permitted the production of compact, hard everlasting pea-wheat extrudates for use in vegetarian lunch dishes.

Differential responses of B vitamins in black soybean seeds

This study was aimed to determine the contents and the association of B vitamins from seeds of 10 black and one yellow soybean (Glycine max (L.) Merr.) varieties with either green or yellow cotyledon. Thiamine, flavin adenine dinucleotide (FAD), riboflavin and total riboflavin were found highest in 'Chengjakong', while flavin mononucleotide (FMN) was greatest in 'Mirang'. Nicotinic acid and total vitamin B3 were highest in 'Shingi' as a yellow soybean variety but pantothenic acid and pyridoxine contents were greatest in 'Tawon' and 'Mirang', respectively. These content variations of B vitamins directly reflected the wide segregation of soybean varieties on the principal component analysis (PCA) scores plot, indicating that these 4 soybean varieties appeared to be least associated with other soybean varieties based on the different responses of B vitamins. The results of cluster and correlation analyses presented that the cotyledon colour of soybean seed contributed to a variation of B vitamin contents. Overall, the results suggest that a wide range of B vitamin contents would be affected by genotypic factors alongside the difference of cotyledon colour.