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The absence of recent data regarding the nutritional needs of modern soybean [Glycine max (L.) Merr.] production systems necessitates a greater comprehensive understanding of nutrient uptake, partitioning, and remobilization. The objective of this study was to evaluate macro‐ and micronutrient accumulation and partitioning in current soybean cultivars. Across 3 site‐years, plants were sampled at seven growth stages and divided into four plant tissue fractions for quantification of nutrient uptake. Accumulation (per ha) of 275 kg N, 21 kg P (48 kg P2O5), 172 kg K (207 kg K2O), 113 kg Ca, 50 kg Mg, 19 kg S, 335 g Zn, 371 g Mn, 325 g B, 849 g Fe, and 63 g Cu were required to produce approximately 3500 and 9500 kg ha−1 of grain and total biomass, respectively. Supplemental fertility modestly increased biomass and yield (2%), but did not alter nutrient partitioning or harvest index. Nutrients with high harvest index (i.e., percentage of total nutrient accumulation partitioned to grain) values included P (81%), N (73%), Cu (62%), and S (61%), which may serve as a limitation to high yield. Seasonal patterns of nutrient accumulation suggested that K and Fe were acquired primarily during late vegetative growth while the uptake of N, P, Ca, Mg, S, Zn, Mn, B, and Cu were more equally distributed between vegetative and seed‐filling growth phases. These results document the rate and duration of macro‐ and micronutrient accumulation in soybean, and highlight the importance of adequate nutrient availability during key crop growth periods.

1. Soil resource partitioning and dispersal limitation have been shown to shape the tree community structure of mature tropical forests, but are poorly studied in the context of forest succession. We examined the relative contributions of both ecological processes to the variation in the species composition of young tropical secondary forests at different spatial scales, and if the relative importance of these two ecological processes changed during succession. At the species level, we examined if the association between species abundances and soil fertility differed between early and late successional species and/or changed over the course of succession. 2. We used vegetation and soil data from 47 secondary forest sites with two plots each in a tropical agricultural landscape. A distance-based redundancy analysis and variation partitioning were employed to examine the relative importance of spatial distance (proxy for dispersal limitation) and heterogeneity in soil nutrients (proxy for soil nutrient partitioning) at the landscape scale, and a linear regression to test their effects at the local scale. We examined interspecific variation in species' responses to successional age and soil nutrients with a joint species distribution model. 3. Dispersal limitation and soil niche partitioning drove considerable variation in the composition of plant communities at local and landscape scales. The relative contribution of these two ecological processes changed with scale (local vs. landscape) and topography (lower slope vs. upper slope plots). At the species level, significant abundance-soil fertility associations were mostly positive. Most species became less responsive to soil nutrients over the first few decades of tropical forest succession, probably because light became the main limiting resource in older forests. 4. Synthesis. Our key finding is that spatial heterogeneity in soil resources and spatial distance jointly drive compositional variation within and across early successional forests. Our results highlight that a network of forest fragments enhances the resilience of ecological processes and the potential of secondary forests to restore and preserve biodiversity in human-modified landscapes. To advance our understanding of ecological succession, we need to move beyond single-factor and local-scale studies and examine the effects of multiple variables on succession at different spatial scales.

Fungus-fertilizer interactions can enhance agricultural productivity and effective resource utilization, however, the study of the effect of arbuscular mycorrhizal fungi (AMF) and phosphorus on soil fertility and nutrient uptake of soybeans under salinity stress is still unclear. In this study, a mixture of three AMFs ( Funneliformis mosseae , Rhizophagus intraradices , and Diversispora epigaea ) was inoculated into the salt-sensitive soybean ( Glycine max (L.) Merr.) cultivar ‘Wuxing No.2’ in a pot experiment set up for inoculation, no inoculation and five levels of phosphorus (P 2 O 5 ) supply (such as 0, 50, 100, 250, 500 mg P kg −1 ), bacterial phosphorus interactions totaling 10 treatments, each treatment 7 replications. Soil nutrient content and soybean nutrient uptake and translocation rates were determined at seasons of flowering pods, tympanic period and harvest period, respectively. Under low phosphorus (50 mg kg −1 ) conditions, the soil available phosphorus content at the seasons of flowering pods increased by 23.11% compared with the uninoculated group. The accumulation of nitrogen, phosphorus, and potassium in the plants increased significantly, with the phosphorus content in leaves reaching 4.72 mg·g −1 , which was 98.50% higher than that in the high-phosphorus non-inoculated treatment. Meanwhile, it optimized nutrient partitioning, promoting the transfer of phosphorus to the stalks (with the phosphorus transport rate in stems being 37.27% in the + AMF P50 treatment) to support grain formation. In contrast, the uninoculated group required a higher phosphorus level (250 mg kg −1 ) to reach the peak of biomass, with the root fresh weight peaking at 13.71 g. The low phosphorus inoculation treatment can improve soil fertility and plant nutrient uptake and utilization, and promote the efficient use of agricultural resources.

Seeds serve as biochemical factories of nutrition, processing, bio-energy and storage related important bio-molecules and act as a delivery system to transmit the genetic information to the next generation. The research pertaining towards delineating the complex system of regulation of genes and pathways related to seed biology and nutrient partitioning is still under infancy. To understand these, it is important to know the genes and pathway(s) involved in the homeostasis of bio-molecules. In recent past with the advent and advancement of modern tools of genomics and genetic engineering, multi-layered ‘omics’ approaches and high-throughput platforms are being used to discern the genes and proteins involved in various metabolic, and signaling pathways and their regulations for understanding the molecular genetics of biosynthesis and homeostasis of bio-molecules. This can be possible by exploring systems biology approaches via the integration of omics data for understanding the intricacy of seed development and nutrient partitioning. These information can be exploited for the improvement of biologically important chemicals for large-scale production of nutrients and nutraceuticals through pathway engineering and biotechnology. This review article thus describes different omics tools and other branches that are merged to build the most attractive area of research towards establishing the seeds as biochemical factories for human health and nutrition.

The physiological processes that underlie the reproductive cycle impose considerable metabolisable protein (MP) demands on a female, especially during the periparturient period. When MP supply falls short of MP demand (i.e. MP becomes scarce), certain, if not all, bodily functions are expected to be penalised. It has been proposed that partitioning of scarce MP is prioritised to reproductive rather than to immune functions. In other words, at times of MP scarcity, the penalty on expression of immunity would be expected to be greater than that on reproduction. This hypothesis forms a nutritional basis for the occurrence of periparturient breakdown of immunity to parasites (BIP), which can be observed in many host–parasite systems. In the present review we explore this nutritional basis, using periparturient sheep infected with the abomasal nematode Teladorsagia circumcincta as an example, and attempt to quantify its occurrence. Evidence supporting the nutritional basis of periparturient BIP is reviewed, covering experiments in which nutrient supply (from both exogenous and endogenous sources) and/or nutrient demand were manipulated. Quantitatively, MP requirements for expression of immunity to T. circumcincta were estimated to be about 1 g/kg metabolic body weight (body weight0·75) per d, approximately 5 % of the maximum MP requirements of periparturient sheep. The major component of this requirement was assumed to be for replenishing irreversible plasma protein losses into the gastrointestinal tract. Although confirmation of this estimate is required, such estimates may be used to improve the known MP requirements of periparturient animals, enabling the extent and the consequences of periparturient BIP to be minimised.

Water stress and sulfur (S) deficiency are two constraints increasingly faced by crops due to climate change and low-input agricultural practices. To investigate their interaction in the grain legume pea (Pisum sativum), sulfate was depleted at the mid-vegetative stage and a moderate 9-d water stress period was imposed during the early reproductive phase. The combination of the stresses impeded reproductive processes in a synergistic manner, reducing seed weight and seed number, and inducing seed abortion, which highlighted the paramount importance of sulfur for maintaining seed yield components under water stress. On the other hand, the moderate water stress mitigated the negative effect of sulfur deficiency on the accumulation of S-rich globulins (11S) in seeds, probably due to a lower seed sink strength for nitrogen, enabling a readjustment of the ratio of S-poor (7S) to 11S globulins. Transcriptome analysis of developing seeds at the end of the combined stress period indicated that similar biological processes were regulated in response to sulfur deficiency and to the combined stress, but that the extent of the transcriptional regulation was greater under sulfur deficiency. Seeds from plants subjected to the combined stresses showed a specific up-regulation of a set of transcription factor and SUMO ligase genes, indicating the establishment of unique regulatory processes when sulfur deficiency is combined with water stress. Moderate water stress combined with sulfur deficiency during seed development in pea synergistically affects reproductive processes, but mitigates the negative impact of the deficiency on the seed transcriptome and rebalances seed globulin composition.

The relationship between feed intake at production levels and enteric CH 4 production in ruminants consuming forage-based diets is well described and considered to be strongly linear. Unlike temperate grazing systems, the intake of ruminants in rain-fed tropical systems is typically below maintenance requirements for part of the year (dry seasons). The relationship between CH 4 production and feed intake in animals fed well below maintenance is unexplored, but changes in key digestive parameters in animals fed at low levels suggest that this relationship may be altered. We conducted a study using Boran yearling steers ( n 12; live weight: 162·3 kg) in a 4 × 4 Latin square design to assess the effect of moderate to severe undernutrition on apparent digestibility, rumen turnover and enteric CH 4 production of cattle consuming a tropical forage diet. We concluded that while production of CH 4 decreased (1133·3–65·0 g CH 4 /d; P < 0·0001), over the range of feeding from about 1·0 to 0·4 maintenance energy requirement, both CH 4 yield (29·0−31·2 g CH 4 /kg DM intake; P < 0·001) and CH 4 conversion factor ( Y m 9·1–10·1 MJ CH 4 /MJ gross energy intake; P < 0·01) increased as intake fell and postulate that this may be attributable to changes in nutrient partitioning. We suggest there is a case for revising emission factors of ruminants where there are seasonal nutritional deficits and both environmental and financial benefits for improved feeding of animals under nutritional stress.

Increasing wheat ( Triticum aestivum L.) yield and grain protein concentration (GPC) without excessive nitrogen (N) inputs requires understanding the genotypic variations in N accumulation, partitioning, and utilization strategies. This study evaluated whether high protein genotypes exhibit increased N accumulation (herein also expressed as N nutrition index, NNI) and partitioning (including remobilization from vegetative organs) compared to low-protein genotypes under low and high N conditions. Four winter wheat genotypes with similar yields but contrasting GPC were examined under two N rates (0 and 120 kg N ha -1 ) across two environments and four growing seasons in Oklahoma, US. As expected, the high-protein genotypes Doublestop CL+ (Dob) and Green Hammer (Grn) had greater GPC than the medium- (Gallagher, Gal) and low-protein genotypes (Iba), without any difference in grain yield. Total plant N accumulation at maturity showed diminishing increases for greater grain yield, and low-protein genotype showed greater N utilization efficiency (NUtE) than high-protein genotypes. The high-protein genotype Grn tended to achieve higher GPC by increasing total N uptake, while Dob exhibited a tendency towards higher N partitioning to grain (NHI). The allometric relationship between total N accumulation and biomass remained unchanged for both high- and low-protein genotypes. The N remobilization patterns differed between high- and low-protein genotypes. As N conditions improved, the proportional contributions of remobilized N from leaves tended to increase, while contributions from stems and chaff tended to decrease or remained unchanged for high-protein genotypes. This study highlights the importance of both N uptake capacity and efficient N partitioning to the grain as critical traits for realizing wheat’s dual goals of higher yield and protein. Leaf N remobilization plays a critical role during grain filling, sustaining plant N status and contributing to protein levels. The higher NUtE observed in the low-protein genotype Iba likely contributed to its lower GPC, emphasizing the trade-off between NUtE and GPC. The physiological strategies employed by high-protein genotypes, such as genotype Grn’s tendency for increased N uptake and Dob’s efficient N partitioning, provide a foundation for future breeding efforts aimed at developing resource-efficient and nutritionally superior wheat genotypes capable of achieving both increased yield and protein.

Hemicelluloses are major components of plant biomass, but their fermentation in the rumens of cattle and other ruminants is poorly understood. We compared four species of the ruminally dominant genus Prevotella and the well-known hemicellulose utilizer, Butyrivibrio fibrisolvens , with respect to degradation of several isolated hemicelluloses (xylans, glucomannan, and xyloglucan). We also performed Illumina sequencing of the V3/V4 region of 16S rRNA genes to determine the relative proportions of Prevotella and Butyrivibrio in hemicellulose-fed enrichment cultures inoculated from ruminal contents of dairy cattle fed a total mixed ration (TMR) rich in hemicelluloses. Results confirmed the xylan fermentation and butyrate production abilities of B. fibrisolvens . Despite their reputation as generalist fermenters, the Prevotella strains poorly fermented these hemicelluloses but exhibited dramatic differences in fermentation end products. Prevotella was much less abundant in mixed bacterial enrichment cultures fed the same TMR than in the ruminal inoculum, yet Prevotella was again the most abundant genus in enrichment cultures fed xylans. By contrast, glucomannan fermentations were dominated by Streptococcus sp. Genera known for hemicellulose degradation ( Butyrivibrio , Ruminococcus , and Fibrobacter ) were not significantly enriched on these hemicelluloses. Substantial differences in fermentation end product distribution from the different hemicelluloses were observed, which would likely affect nutrient partitioning in the host animal. Differences in community composition between in vitro hemicellulose enrichments and inoculum samples emerged at every phylogenetic level, suggesting that in vitro conditions provide unique selective pressures on the bacterial community and also that ruminal bacteria exhibit specialization with respect to hemicellulose utilization.

The NAM-B1 gene is a NAC transcription factor that affects grain nutrient concentrations in wheat (Triticum aestivum). An RNAi line with reduced expression of NAM genes has lower grain protein, iron (Fe), and zinc (Zn) concentrations. To determine whether decreased remobilization, lower plant uptake, or decreased partitioning to grain are responsible for this phenotype, mineral dynamics were quantified in wheat tissues throughout grain development. Control and RNAi wheat were grown in potting mix and hydroponics. Mineral (Ca, Cu, Fe, K, Mg, Mn, P, S, and Zn) and nitrogen (N) contents of organs were determined at regular intervals to quantify the net remobilization from vegetative tissues and the accumulation of nutrients in grain. Total nutrient accumulation was similar between lines, but grain Fe, Zn, and N were at lower concentrations in the NAM knockdown line. In potting mix, net remobilization of N, Fe, and Zn from vegetative tissues was impaired in the RNAi line. In hydroponics with ample nutrients, net remobilization was not observed, but grain Fe and Zn contents and concentrations remained lower in the RNAi line. When Fe or Zn was withheld post-anthesis, both lines demonstrated remobilization. These results suggest that a major effect of the NAM genes is an increased efflux of nutrients from the vegetative tissues and a higher partitioning of nutrients to grain.