Abiotic and biotic stresses activate long-terminal repeat retrotransposons in photosynthetic eukaryotes. In this article, we reviewed the ways that retrotransposons are activated by environmental stimuli to affect restructuring and diversification of the host genome. We recommend the use of RNA-Seq data of other plant species (e.g., Rhazya stricta) to get a deeper view of activation patterns.

The increasing climatic variability results in wheat being exposed to more frequent adversities including combined low temperature and drought/waterlogging. The physiological, proteomic and transcriptional responses of wheat plants to these combined stresses were reported. The knowledge will help comprehensively understand the climate change impacts on wheat production and help optimise water management strategy to cope with the abiotic stresses.

It has been suggested that mixed forests may be more productive than mono-specific forests, but not much is known about belowground (root) production. With an ingrowth core study in 100 plots in an old-growth forest, we show that species identity is important, whereas species diversity per se influenced only fine root turnover but not fine root production.

The effects of localised soil compaction plus nutrient availability on root system architecture (RSA) and root growth dynamics have scarcely been investigated. We investigated the impact of heterogeneous soil conditions on barley RSA, and root and shoot growth using split-root rhizotrons, and observed dynamic compensatory alterations, particularly in lateral root initiation. In loose compartments formation of lateral roots started earlier than in uniform treatments and was significantly increased in compacted compartments when only these compartments were fertilised.

ERF transcription factors are implicated in a range of biological processes. However, molecular functions of most pepper ERFs remain uncharacterised. We have shown that overexpression of a pepper CaERF5 gene in tobacco enhances resistance to a bacterial disease, likely by activation of defence genes. Our results suggest that CaERF5 acts as a positive regulator in plant defence, and that overexpression of CaERF5 can be used to enhance disease resistance in crop species.

Designing an effective phenotyping strategy requires thorough understanding of plant survival under salt stress. This study aimed at characterising rice cultivars differing in salinity tolerance based on changes in chlorophyll fluorescence characteristics, growth parameters and ion accumulation. Salinity factor index calculated from PI_ABS clearly distinguished tolerance level among the cultivars. Some new salt-tolerant cultivars were identified, which could serve as donors in breeding programme and for identification of additional QTL/genes.

Salinity is a growing problem worldwide that causes a significant reduction in crop yields. We have addressed this problem by manipulating the programmed cell death pathways in rice, resulting in enhanced salt stress tolerance. The implication is that farmers could grow rice containing such a trait in environments where salinisation of the soil exists, thereby addressing food security needs.

Marine diatoms show diverse growth responses to increasing pCO₂ and the associated changes to seawater carbonate system. These responses reflect physiological diversities across diatoms, but also complex interactions among responses to pCO_2, pH, nutrient availability, light levels and fluctuations. Predicting net diatom growth responses to ocean acidification will require integrated measures.

Conductance to CO₂ diffusion within leaves (mesophyll conductance) forms a significant and variable limitation on photosynthesis but remains poorly understood. Here, mesophyll conductance was found to vary 2-fold among wheat genotypes, and to be positively related to photosynthetic rate. These results suggest that both photosynthetic rate and water-use efficiency could be improved through breeding for higher mesophyll conductance.

Heat events are a natural summer occurrence in Australian vineyards but costly in lost production, thus, protecting vines during these events is an economically important issue. We have assessed spraying water onto vines for brief periods as a means of reducing canopy temperatures. The canopies were nearly 10°C cooler during the heat events and both yields and berry composition were improved, suggesting spraying water onto vines is an effective means of reducing impacts of high temperatures.

Since the connection between cyclins and plant development involving plant hormones is poorly understood, we characterise the SlCycA3 gene to determine the effect of A3-type cyclin gene on cell-cycle-related plant growth and its regulation mechanisms under auxin treatment. Our results showed that overexpression of the SlCycA3 gene accelerated root growth and development. Cyclin abundance may function as a regulator to control root growth in response to plant hormone treatment.

Measurement of the phloem translocation of herbicides is a challenge, especially at the initial development of compounds. B. distachyon was evaluated for potential use in phloem bioassay showing a clear evidence of xylem discontinuity. This novel bioassay provides an opportunity to determine quantitatively phloem mobility of molecules in vivo without the use of radiolabel and with a high throughput during the early stages of pesticides research.

Climate change scenarios predict an increase in extreme climatic events. In our study we tested the effects of multiple extreme events on plant performance and trait intraspecific variation, and discovered that trait intraspecific variation was not induced by extreme events. However, multiple extreme events have quantitatively and qualitatively different impacts on plant performance than single events and it is difficult to predict those impacts beforehand, which hampers predicting plant responses to a future climate.

Leaf initiation rate (LIR) is strongly modulated by temperature and commonly predicted solely based on thermal time. We investigated the effects of photosynthetic photon flux density (PPFD) on LIR in cucumber and tomato plants. LIR and photosynthate availability in the apical bud substantially decreased at low PPFD in both species suggesting that PPFD is limiting for LIR most likely via photosynthate availability in the apical bud.

In order to further the use of plant biomass stable isotope ratios as a proxy for environmental stressors such as drought and salinity, we must understand the long-term impact of such stressors on the isotopic composition of leaf water. Here we show with stomatal count and artificial leaves, that the lower leaf water isotopic enrichment observed in mangroves compared to freshwater plants is due their larger and lower density of stomatal pores. Our results have important implications in interpreting paleoclimate with tree ring oxygen isotope ratios, since stomatal frequency and size has varied over the ages.

The intraspecific diversity of Sangiovese and Montepulciano grapevine varieties is accentuated under early water deficit. Higher physiological and productive efficiency under non-limiting water supply noted by the near-isohydric Montepulciano compared with the near-anisohydric Sangiovese was reversed when both cultivars were subjected to a pre-veraison water deficit. Sangiovese had excellent net CO₂ exchange (NCER) recovery upon re-watering and is confirmed to be better adapted to dry/hot conditions.

Soil water extraction by perennial grasses under drought conditions is not well understood but has important implications for agricultural productivity as the climate changes. We studied the variation among 18 bermudagrasses for soil water extraction and drought resistance in a drying soil profile. We found that drought resistance was associated with rhizome production rather than rooting depth and root distribution.

The combination of double C¹³ and N¹⁵ labelling and subsequent compound-specific analysis in amino acids showed the imbalance observed between CO₂ and N₂ fixation in nodulated alfalfa plants. It provided a novel conclusion about the use and importance of pre-existing reserves in the production of new organic matter during growth.

Tree stems shrink and expand in radius with transpiration-induced negative pressures. So far, these fluctuations have mainly been related to shrinkage in living cells of the bark which act as a buffer for water potential peaks in the rigid water transport system of the wood. Here we propose that Eucalyptus globulus as a fast-growing species maintains immature, non- or partially lignified xylem which acts as an additional water storage in the sapwood and, thus, alters the performance of the water supply system of the entire tree.

Canopy temperature has been identified as a real-time, plant-based tool which may provide gains in irrigation efficiency. However, canopy temperature response to water stress is confounded by environmental conditions. In order to better use canopy temperature for irrigation scheduling, the relationship between environmental conditions and plant water stress physiology was explored. From this research we conclude that point-in-time measures of canopy temperature for water stress detection are better understood with the inclusion of atmospheric vapour pressure deficit.

Understanding the interactive effects of temperature and water availability on plant carbon exchange is essential to predict the impact of environmental changes on plant productivity. Here, soil drying was used to determine the short-term temperature response of photosynthesis and respiration under varying soil water contents, and to resolve their combined effects. Water availability influenced the temperature sensitivity of photosynthesis and respiration, and altered the balance between carbon gain and loss.

Carob tree is a crop well adapted to calcareous soils that does not develop iron (Fe) chlorosis. The lack of Fe triggers an increase of organic acids and activity of the root ferric chelate-reductase (FC-R) as response mechanisms. Understanding physiological mechanisms of this species could improve the strategy to cope with nutritional imbalances and avoid excessive application of fertilisers.

To keep wheat productive under high temperature and long photoperiod requires understanding processes regulating floret and grain number. Genotypes with high stem soluble carbohydrates had slower floret development and higher grain set at high temperature; higher spike biomass and glucose and more florets and grains per spike across environments. Our findings highlight an interaction between carbohydrates and floret development that could be exploited in warmer environments.

This paper presents, for the first time, results indicating that Physcomitrella patens (the model organism for bryophytes) is desiccation tolerant. We provide a method to induce desiccation tolerance with supporting evidence for tolerance. This work provides an outline for future studies on desiccation using an organism both amenable to cultivation and in possession of a fully sequenced genome.

Asymmetric warming causes long-term reduction of diurnal temperature range with strong negative effects on plant growth and yield. Twelve rice cultivars were sorted by their high night temperature (HNT) response and sensitivity specific differences in growth parameters but not respiration rate were reported, while respiration rate and carbon depletion were excluded as primary sources of HNT sensitivity. Knowledge on HNT tolerant rice will support breeding of cultivars for changed global climate conditions.

Advanced molecular techniques require phenotyping of large rice populations. In this study, our aim was to identify useful indicators for reliable selection of rice genotypes for productivity in saline soil with minimal time and cost. The measure of Na⁺ exclusion (leaf Na⁺ concentration) was validated as the most reliable trait for salt tolerance, as long as the plants were grown for at least 3 weeks and moved past the osmotic-stress dominated phase. The most sensitive growth components were tiller number plant^–1 and shoot water content (water g g^–1 dry weight), and these were correlated significantly with leaf Na⁺ and injury scores.

The circadian clock is the endogenous mechanism that adjusts physiology and metabolism to time of day. Glycine-rich RNA-binding proteins, which participate in the output signal of the circadian clock in source organs, exhibit circadian oscillations that depend on developmental and temperature signals in tomato fruit. Studies on the timing of the interactions and their effects on fruit growth and metabolism provide a molecular mechanism connecting oscillators with outputs in fruits.

Plants inhabiting Mediterranean coastal areas display contrasting strategies to cope with a wide range of stresses. Also, Mediterranean areas display a high level of biodiversity. Here we explored strategies adopted by two co-occurring woody evergreens when suffering from an excess of soil salinity. Species-specific leaf life-span and drought-tolerance strategies are tightly related with salt-exclusion mechanisms, which, in turn, greatly impacts upon salt-induced metabolic adjustments.

Understanding the biochemical and molecular determinants of nitrogen nutrition in grapevine is important for the quality of production and environmental protection. The nitrate uptake mechanism was studied in this crop for the first time, focusing on the high-affinity component and the need for energy coupling, highlighting nitrate induction in grapevine. The involvement of the NRT2, NRT3 and plasma membrane H⁺-ATPase gene families in nitrate uptake by roots was evaluated.

Grain yield is closely associated with grain number in barley, and improved spikelet survival is therefore an important trait for increasing grain yield. We identified awn primordium to tipping as the most critical subphase related to spikelet abortion, regardless of growing conditions. Spikelet survival was highly genetically controlled and an in-depth analysis of this trait is a worthwhile target for increasing yield.

Salinity is a globally increasing problem threatening agricultural production and affecting plant growth through an osmotic stress that affects root water uptake. This is a comprehensive analysis of root water uptake properties (hydraulic conductivity) in wheat (Triticum aestivum L.) in response to salinity. Salinity reduces the hydraulic conductivity of roots and appears to prevent developmental changes in root water uptake pathways from taking place as they occur in nonstressed plants.

Lateral root emergence is tightly regulated, although molecular components involved in this process are still largely unknown. This study showed that overexpression of a basic/helix-loop-helix (bHLH) transcription factor AtbHLH112 specifically suppresses lateral root emergence by decreasing the local auxin level and downregulating expression of cell-wall-remodelling (CWR) genes. Our results suggest that AtbHLH112 may represent a novel repressor of cell separation during lateral root emergence.

The productivity and persistence of white clover are both dependent on shoot branching, so the negative effect of P deficiency on branching has profound effects. Regulation of branching in P-limited plants was shown to be via root-supplied promoter signal rather than by inhibitory signals or P nutrition. For clover, and possibly other stoloniferous species, P-deficiency indirectly inhibits branching by down regulating root-supplied promoter signal and the strigolactone pathway plays a minor role.