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• We explored the effects of atmospheric CO₂ concentration (Cₐ) and vapor pressure deficit (VPD) on putative mechanisms controlling leaf elongation in perennial ryegrass. • Plants were grown in stands at a Cₐ of 200, 400 or 800 μmol mol–1 combined with high (1.17 kPa) or low (0.59 kPa) VPD during the 16 h-day in well-watered conditions with reduced nitrogen supply. We measured day : night-variation of leaf elongation rate (LERday : LERnight), final leaf length and width, epidermal cell number and length, stomatal conductance, transpiration, leaf water potential and water-soluble carbohydrates and osmotic potential in the leaf growth-and-differentiation zone (LGDZ). • Daily mean LER or morphometric parameters did not differ between treatments, but LERnight strongly exceeded LERday, particularly at low Cₐ and high VPD. Across treatments LERday was negatively related to transpiration (R² = 0.75) and leaf water potential (R² = 0.81), while LERnight was independent of leaf water potential or turgor. Enhancement of LERnight over LERday was proportional to the turgor-change between day and night (R² = 0.93). LGDZ sugar concentration was high throughout diel cycles, providing no evidence of source limitation in any treatment. • Our data indicate a mechanism of diel cycling between daytime hydraulic and night-time stored-growth controls of LER, buffering Cₐ and daytime VPD effects on leaf elongation.

The objective of this study was to assess the effect of cutting time on the nutritional composition and dehydration rate of stargrass, as well as the nutritional value of the hay as a function of storage time. Two plant cutting times were analyzed: at 13:00 (H13) and 17:00 (H17). After cutting, the dehydration rate of both the plant and its fractions until baling was monitored. The bales were checked for nutritional composition and digestibility after 30, 60, 90 and 120 days. At the time of cutting, a difference was observed for the concentrations of ethanol-soluble carbohydrates, which were higher for H17 (90.3 g kg-1) compared to H13 (52.9 g kg-1). Leaf dehydration rates were higher in the H17 treatment. Cutting time had no influence on the nutritional value of the hay. With storage time, there was an increase in the levels of neutral detergent fiber and acid detergent fiber, and a reduction in the content of ethanol-soluble carbohydrates. It was concluded that cutting at 17:00 allows for a greater accumulation of soluble carbohydrates in the plant. Cutting time does not change the time required for dehydration and the nutritional value of the hay. Storage time reduces soluble components and increases fibrous constituents

In wheat stems, the levels of fructan‐dominated water‐soluble carbohydrates (WSC) do not always correlate well with grain yield. Field drought experiments were carried out to further explain this lack of correlation. Wheat (Triticum aestivum) varieties, Westonia, Kauz and c. 20 genetically diverse double haploid (DH) lines derived from them were investigated. Substantial genotypic differences in fructan remobilization were found and the 1‐FEH w3 gene was shown to be the major contributor in the stem fructan remobilization process based on enzyme activity and gene expression results. A single nucleotide polymorphism (SNP) was detected in an auxin response element in the 1‐FEH w3 promoter region, therefore we speculated that the mutated Westonia allele might affect gene expression and enzyme activity levels. A cleaved amplified polymorphic (CAP) marker was generated from the SNP. The harvested results showed that the mutated Westonia 1‐FEH w3 allele was associated with a higher thousand grain weight (TGW) under drought conditions in 2011 and 2012. These results indicated that higher gene expression of 1‐FEH w3 and 1‐FEH w3 mediated enzyme activities that favoured stem WSC remobilization to the grains. The CAP marker residing in the 1‐FEH w3 promoter region may facilitate wheat breeding by selecting lines with high stem fructan remobilization capacity under terminal drought.

The objective of the present study was to investigate the potential of vegetable soybean (Edamame) cultivation in Lithuania. Six soybean varieties were grown in an open field. Our data showed that the plants of the ‘Chiba Green’ variety were the shortest. Such plants had higher chlorophyll index and photosynthesis intensity. Variety ‘Midori Giant’ had more branches than plants of other varieties. The highest yield was produced by the plants of the ‘Chiba Green’ variety. Higher protein content was found in beans of the ‘Chiba Green’ variety. However, there were no differences found in soluble carbohydrates and micro- and macroelement contents between the varieties. In summary, the results revealed that of the tested varieties, the most suitable and useful for the cultivation under Lithuanian climate conditions was the ‘Chiba Green’ vegetable soybean variety.

In this study, we assessed the effects of replacing cracked corn grain with soybean molasses (SM) on the feed intake and ingestive behavior of 30 uncastrated lambs, Santa Inês × Dorper crossbreed, finished in feedlot. The treatments were 0 g kg-1 DM SM (CON), 150 g kg-1 DM SM (SM15), and 300 g kg-1 DM SM (SM30). Dry matter and nutrient intake were evaluated, in addition to ingestive behavior variables such as interactions with the feed bunker, stereotypes, chewing activities, and time spent in feed bunkers in a 24-h period at three different times during the feedlot period (beginning, middle, and end). The replacement of cracked corn grain with SM decreased the dry matter intake % BW (p < 0.05) and ether extract intake (p < 0.05) only at the final feedlot period. Additionally, it linearly decreased the cud chewing time p = 0.01) and increased the number of cuds (p = 0.02). The inclusion of SM allowed for a more stable feed intake during the feeding times (p < 0.05). Replacing cracked corn grain with SM in feedlot lamb diets offers a viable alternative without negatively affecting feed intake, even at levels of up to 300 g kg-1. This substitution improves the stability of feed intake.

In wheat, stem water soluble carbohydrates (WSC), composed mainly of fructans, are the major carbon sources for grain filling during periods of decreasing photosynthesis or under drought stress after anthesis. Here, in a field drought experiment, WSC levels and associated enzyme activities were followed in different stem segments (peduncle, penultimate internode, lower parts of stem, and sheath) during grain filling. The focus was on two double haploid (DH) lines, DH 307 and DH 338, derived from a Westonia/Kauz cross, two drought-tolerant wheat varieties that follow different drought adaptation strategies during grain filling. The results showed that in irrigated plants, in the period between 20 and 30 days after anthesis (DAA), 70-80% of WSC were fructans. Before and after this period, the fructan proportion varied from 10 to 60%, depending on the location along the stem. Under drought, the fructan proportion changed, depending on genotype, and developmental stages. After anthesis, stem fructans accumulation occurred mainly in the peduncle and penultimate internode until 14 DAA in both DH lines, with clear genotypic variation in subsequent fructan degradation under drought. In DH 307 a significant reduction of fructans with a concomitant increase in fructose levels occurred earlier in the lower parts of the stem and the sheath, as compared to DH 338 or other stem segments in both lines. This was associated with an earlier increase of grain weight and thousand grain weight in DH 307. Spatiotemporal analysis of fructan dynamics and enzymatic activities in fructan metabolism revealed that several types of FEHs are involved in fructan remobilization to the grain under drought.

Forage legumes have a relatively high biomass yield and crude protein content, but their grazed and harvested biomass lacks the high-energy carbohydrates required to meet the productivity potential of modern livestock breeds. Because of their low carbohydrate content, forage legume diets are typically supplemented with starch rich cereal grains or maize (Zea mays), leading to the disruption of local nutrient cycles. Although plant leaves were first reported to accumulate starch in a diurnal pattern over a century ago, leaf starch content has yet to be exploited as an agronomic trait in forage crops. Forage legumes such as red clover (Trifolium pratense) have the genetic potential to accumulate up to one third of their leaf dry mass as starch, but this starch is typically degraded at night to support nighttime growth and respiration. Even when diurnal accumulation is considered with regard to the time the crop is harvested, only limited gains are realized due to environmental effects and post-harvest losses from respiration. Here we present original data for starch metabolism in red clover and place it in the broader context of other forage legumes such as, white clover (T. repens), and alfalfa (Medicago sativa). We review the application of recent advances in molecular breeding, plant biology, and crop phenotyping, to forage legumes to improve and exploit a potentially valuable trait for sustainable ruminant livestock production.

• Quantitative trait locus (QTL) mapping, which can be a useful tool for dissecting complex traits, has been used here to study the regulation of fructan metabolism in temperate forage grasses. • An F2 mapping family, derived from a high water-soluble carbohydrate (WSC) x low WSC cross, was used to map fructans and the other components of WSC (sucrose, glucose and fructose) in leaves and tiller bases of perennial ryegrass (Lolium perenne) in spring and autumn. To characterize regions of the genome that control basic carbohydrate metabolism, a strategy to minimize the impact of genotype (G) x environment (E), and E-effects on the characterization of G-effects, was adopted. • Most traits were highly variable within the family. There was also considerable year-to-year environmental variation. However, significant genetic effects were detected, and several traits had high broad-sense heritability. QTL were identified on chromosomes 1, 2, 5 and 6. Leaf and tiller base QTL did not coincide. Individual QTL explained between 8 and 59% of the total phenotypic variation in the traits. • Fructan turnover, metabolism and their genetic control, and the effect of environment, are discussed in the context of the results.

The role of fructan in growth and drought-stress responses of perennial ryegrass (Lolium perenne) was investigated in an F₂ mapping family that segregates for carbohydrate metabolism. A quantitative trait locus approach was used to compare the genetic control of traits. Growth and drought-stress traits were extremely variable within the family. Most traits had high broad-sense heritability. Quantitative trait loci (QTL) were identified for most traits; the maximum number of QTL per trait was four. Between 11% and 75% of total phenotypic variation was explained. Few growth-trait QTL coincided with previously identified fructan QTL. A cluster of drought-trait QTL was close to two previously identified regions of the genome with tiller base fructan QTL in repulsion. The high sugar parent contributed few alleles that increased 'reserve-driven' growth or performance during drought-stress. Correlation of growth and drought-stress traits with fructan content was low and increasing fructan content per se would not appear to improve drought resistance. Complex patterns of carbohydrate partitioning and metabolism within the cell may explain contradictory relationships between carbohydrate content and growth/stress-resistance traits.

The Cerrado biome covers a large area of central Brazil, containing a mosaic of physiognomies determined by soil fertility, seasonal rainfall, and fire. The ground layer vegetation presents a high eudicot diversity and a high proportion of belowground phytomass, represented mainly by a diversity of underground organs storing carbohydrates. Fructans and other soluble carbohydrates are claimed to be more than reserves, conferring protection against abiotic stresses due to osmoregulation properties and rapid turnover. Inulin- and levan-type fructans are prominent and found respectively in the underground organs of Asteraceae and Amaranthaceae, abundant families in the herbaceous Cerrado flora. Poaceae, mainly Panicoideae, is also abundant and accumulates glucose, sucrose, and malto-oligosaccharides, but not fructans, in contrast with temperate grasses. Here, we review evidence that fructans in the herbaceous flora of the Cerrado play a significant role in tolerance to drought and fire, promoting the rapid recovery of the ground-layer vegetation after environmental disturbances.