Interactional Effects of Climate Change Factors on the Water Status, Photosynthetic Rate, and Metabolic Regulation in Peach

Integrated nexus approach to assessing climate change impacts on grassland ecosystem dynamics: A case study of the grasslands in Tanzania

This study addresses the intricate interplay between climate, vegetation, and livestock dynamics in Tanzania within the Climate-Vegetation-Livestock (CVL) nexus through a quantitative assessment. By examining the temporal and spatial relationships between vegetation indices (NDVI, EVI, NPP) and key climatic variables (Precipitation, Temperature, Evapotranspiration) from 2009 to 2019, and projecting to 2050, this research aims to elucidate vegetation responses to climate change and its subsequent impacts on livestock. To this end, the relationship between the vegetation dynamics indicators (NDVI, NPP) and climate parameters is evaluated to quantify the vegetation response to climate change using statistical models. Next, an examination of multicollinearity is conducted to investigate potential interactions (nexus) between variables, incorporating the correlation among independent variables. Notably, the evaluation of performance and accuracy for the mentioned models is conducted through the cross-validation method and validation indices. Ultimately, the variation between projected NPP and NDVI (average for 2040-2060) and the present NPP and NDVI (average for 2009-2020) identifies the regions that are most likely susceptible, showcasing the vegetation cover's reaction to climate change in different emission scenarios. The results unveil significant spatio-temporal variations in vegetation dynamics influenced by climatic factors, where higher precipitation and temperatures correlate with increased vegetation health and productivity. The projected fluctuations in NDVI and NPP values indicate varying trends across different regions, with a general decrease in vegetation density and productivity from the northeast to the west under both RCP2.6 and RCP8.5 scenarios by 2050. This decline is attributed to anticipated changes in precipitation and temperature patterns driven by climate change. Furthermore, significant declines in vegetation density and productivity under emission scenarios, particularly in the southern regions compared to the present, suggest greater vulnerability to climate change impacts. This highlights the need for targeted mitigation strategies in these vulnerable areas. Meanwhile, northeast areas under both NDVI and NPP will remain unchanged across both climate scenarios. Moreover, analysis of livestock distribution maps indicates areas of vulnerability under climate change scenarios, with implications for future livestock management and agricultural practices. These findings underscore the importance of proactive planning and targeted interventions to enhance resilience and sustainable development in vulnerable regions, emphasizing the need for integrated approaches that consider the complex interactions between climate, vegetation, and livestock dynamics.

Interactive Effect of Cultivars, Crop Years and Rootstocks on the Biochemical Traits of Prunus persica (L.) Batsch Fruits

Peach fruit is one of the most economically widespread temperate fruits, whose productivity, and nutritional and sensory qualities are determined by interactions among several environmental and genetic factors, rootstocks, agronomic practices and pedo-climatic conditions. In recent years, climate change has prompted peach breeding programs to use specific rootstocks that are well adapted to unusual soil and climate characteristics, thus improving the plant's adaptability and fruit quality. The aim of this work was to assess the biochemical and nutraceutical profile of two different peach cultivars, considering their growth on different rootstocks over three crop years. An analysis was carried out evaluating the interactive effect of all factors (i.e., cultivars, crop years and rootstocks) revealing the advantages or disadvantages on growth of the different rootstocks. Soluble solids content, titratable acidity, total polyphenols, total monomeric anthocyanins and antioxidant activity in fruit skin and pulp were analyzed. An analysis of variance was performed to assess the differences between the two cultivars considering the effect of rootstock (one way) and crop years, rootstocks and their interaction (two ways). In addition, two principal component analyses were performed separately on the phytochemical traits of the two cultivars to visualize the distributions of the five peach rootstocks during the three crop years. The results showed that fruit quality parameters are strongly dependent on cultivars, rootstocks and climatic conditions. All these aspects could be useful for the choice of rootstock in relation to agronomic management, making this study a valuable tool for choosing the best rootstock, considering simultaneously more factors affecting peaches' biochemical and nutraceutical profile.

Plant Growth Regulators Improve Grain Production and Water Use Efficiency of Foeniculum vulgare Mill. under Water Stress

The development of methods increasing plant water use efficiency (WUE) would enhance the ability to grow wild aromatic and medicinally important species. The aim of this research was to determine the effect of plant growth regulators (PGRs) applied by spraying on stress resistance and WUE of fennel subjected to water stress. Plants in the generative stage were more drought tolerant than those in the vegetative stage. Water stress at vegetative stage decreased plant biomass and grain yield by 60% and 61%, respectively. Severe water stress in vegetative stage reduced grain production by 56%, and grains had 43% lower mass than those from non-stressed plants. Application of PGRs at both stages of growth increased grain yield and biomass, but the magnitude of increase depended on the type and application time of PGRs. Plants grown in well-watered conditions and sprayed with methyl jasmonate during the vegetative stage had the highest grain production (2.7 g plant⁻¹), whereas under moderate water stress, plants yielded the best (2.1 g plant⁻¹) when sprayed with epibrassinolide. The maximum WUE for grain (0.91 g L⁻¹) and essential oil production (20 mg L⁻¹) was noted in plants exposed to moderate stress and treated with methyl jasmonate during the vegetative stage.

Influence of Climate Change on Metabolism and Biological Characteristics in Perennial Woody Fruit Crops in the Mediterranean Environment

The changes in the state of the climate have a high impact on perennial fruit crops thus threatening food availability. Indeed, climatic factors affect several plant aspects, such as phenological stages, physiological processes, disease-pest frequency, yield, and qualitative composition of the plant tissues and derived products. To mitigate the effects of climatic parameters variability, plants implement several strategies of defense, by changing phenological trends, altering physiology, increasing carbon sequestration, and metabolites synthesis. This review was divided into two sections. The first provides data on climate change in the last years and a general consideration on their impact, mitigation, and resilience in the production of food crops. The second section reviews the consequences of climate change on the industry of two woody fruit crops models (evergreen and deciduous trees). The research focused on, citrus, olive, and loquat as evergreen trees examples; while grape, apple, pear, cherry, apricot, almond, peach, kiwi, fig, and persimmon as deciduous species. Perennial fruit crops originated by a complex of decisions valuable in a long period and involving economic and technical problems that farmers may quickly change in the case of annual crops. However, the low flexibility of woody crops is balanced by resilience in the long-life cycle.

5-Aminolevulinic Acid and 24-Epibrassinolide Improve the Drought Stress Resilience and Productivity of Banana Plants

Plant growth, development, and productivity are adversely affected under drought conditions. Previous findings indicated that 5-aminolevulinic acid (ALA) and 24-epibrassinolide (EBL) play an important role in the plant response to adverse environmental conditions. This study demonstrated the role of ALA and EBL on oxidative stress and photosynthetic capacity of drought-stressed 'Williams' banana grown under the Egyptian semi-arid conditions. Exogenous application of either ALA or EBL at concentrations of 15, 30, and 45 mg·L-1 significantly restored plant photosynthetic activity and increased productivity under reduced irrigation; this was equivalent to 75% of the plant's total water requirements. Both compounds significantly reduced drought-induced oxidative damages by increasing antioxidant enzyme activities (superoxide dismutase 'SOD', catalase 'CAT', and peroxidase 'POD') and preserving chloroplast structure. Lipid peroxidation, electrolyte loss and free non-radical H2O2 formation in the chloroplast were noticeably reduced compared to the control, but chlorophyll content and photosynthetic oxygen evolution were increased. Nutrient uptake, auxin and cytokinin levels were also improved with the reduced abscisic acid levels. The results indicated that ALA and EBL could reduce the accumulation of reactive oxygen species and maintain the stability of the chloroplast membrane structure under drought stress. This study suggests that the use of ALA or EBL at 30 mg·L-1 can promote the growth, productivity and fruit quality of drought-stressed banana plants.

Phytotoxic effect and molecular mechanism induced by graphene towards alfalfa (Medicago sativa L.) by integrating transcriptomic and metabolomics analysis

Although the widespread use of nanoparticles has been reported in various fields, the toxic mechanisms of molecular regulation involved in the alfalfa treated by nanomaterials is still in the preliminary research stage. In this study, Bara 310 SC (Bara, tolerant genotype) and Gold Empress (Gold, susceptible genotype) were used to investigate how the leaves of alfalfa interpret the physiological responses to graphene stress based on metabolome and transcriptome characterizations. Herein, graphene at different concentrations (0, 1% and 2%, w/w) were selected as the analytes. Physiological results showed antioxidant defence system and photosynthesis was significantly disturbed under high environmental concentration of graphene. With Ultra high performance liquid chromatography electrospray tandem mass spectrometry (UPLC-ESI-MS/MS), 406 metabolites were detected and 62/13 and 110/58 metabolites significantly changed in the leaves of Gold/Bara under the 1% and 2%-graphene treatments (w/w), respectively. The most important metabolites which were accumulated under graphene stress includes amino acids, flavonoids, organic acids and sugars. Transcriptomic analysis reveals 1125 of core graphene-responsive genes in alfalfa that was robustly differently expressed in both genotypes. And differential expression genes (DEGs) potentially related to photosynthetic enzymes, antioxidant enzymes, amino acids metabolism, and sucrose and starch metabolic which finding was supported by the metabolome study. Gold was more disturbed by graphene stress at both transcriptional and metabolic levels, since more stress-responsive genes/metabolites were identified in Gold. A comprehensive analysis of transcriptomic and metabolomic data highlights the important role of amino acid metabolism and nicotinate and nicotinamide metabolism pathways for graphene tolerance in alfalfa. Our study provide necessary information for better understanding the phytotoxicity molecular mechanism underlying nanomaterials tolerance of plant.

Water Deficit Modulates the CO2 Fertilization Effect on Plant Gas Exchange and Leaf-Level Water Use Efficiency: A Meta-Analysis

Elevated atmospheric CO2 concentrations ([eCO2]) and soil water deficits significantly influence gas exchange in plant leaves, affecting the carbon-water cycle in terrestrial ecosystems. However, it remains unclear how the soil water deficit modulates the plant CO2 fertilization effect, especially for gas exchange and leaf-level water use efficiency (WUE). Here, we synthesized a comprehensive dataset including 554 observations from 54 individual studies and quantified the responses for leaf gas exchange induced by e[CO2] under water deficit. Moreover, we investigated the contribution of plant net photosynthesis rate (P n ) and transpiration rates (T r) toward WUE in water deficit conditions and e[CO2] using graphical vector analysis (GVA). In summary, e[CO2] significantly increased P n and WUE by 11.9 and 29.3% under well-watered conditions, respectively, whereas the interaction of water deficit and e[CO2] slightly decreased P n by 8.3%. Plants grown under light in an open environment were stimulated to a greater degree compared with plants grown under a lamp in a closed environment. Meanwhile, water deficit reduced P n by 40.5 and 37.8%, while increasing WUE by 24.5 and 21.5% under ambient CO2 concentration (a[CO2]) and e[CO2], respectively. The e[CO2]-induced stimulation of WUE was attributed to the common effect of P n and T r, whereas a water deficit induced increase in WUE was linked to the decrease in T r. These results suggested that water deficit lowered the stimulation of e[CO2] induced in plants. Therefore, fumigation conditions that closely mimic field conditions and multi-factorial experiments such as water availability are needed to predict the response of plants to future climate change.

Triacontanol attenuates drought-induced oxidative stress in Brassica juncea L. by regulating lignification genes, calcium metabolism and the antioxidant system

Effect of triacontanol on drought-induced stress was studied in Brassica juncea L. Foliage of sixteen-days-old plants was sprayed with concentrations (0, 10, 20 and 30 μM) of triacontanol (TRIA) for 7 days. Subsequently, plants were subjected to drought stress (10% polyethylene glycol, PEG6000) for 7 days. Drought stress increased oxidative stress (TBARS, O₂^●- and H₂O₂), however, their contents were reduced by TRIA. Total soluble sugars, reduced glutathione, and proline content in stressed plants were increased by TRIA. Activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR), catalase (CAT), and phenylalanine ammonia-lyase (PAL) activity were significantly increased in a dose-dependent manner with TRIA. Potassium (K⁺) level declined, while magnesium (Mg²⁺) and calcium (Ca²⁺) contents increased. The elevated level of lignin under drought with TRIA was significantly associated with MYB46 and PAL gene expression patterns. Altogether, our results suggest that foliar spray of 20 μM TRIA was more operative in reducing the negative impact of drought stress in B. juncea by regulating the antioxidant system, calcium, and lignification.

Temperate Fruit Trees under Climate Change: Challenges for Dormancy and Chilling Requirements in Warm Winter Regions

Adequate chill is of great importance for successful production of deciduous fruit trees. However, temperate fruit trees grown under tropical and subtropical regions may face insufficient winter chill, which has a crucial role in dormancy and productivity. The objective of this review is to discuss the challenges for dormancy and chilling requirements of temperate fruit trees, especially in warm winter regions, under climate change conditions. After defining climate change and dormancy, the effects of climate change on various parameters of temperate fruit trees are described. Then, dormancy breaking chemicals and organic compounds, as well as some aspects of the mechanism of dormancy breaking, are demonstrated. After this, the relationships between dormancy and chilling requirements are delineated and challenging aspects of chilling requirements in climate change conditions and in warm winter environments are demonstrated. Experts have sought to develop models for estimating chilling requirements and dormancy breaking in order to improve the adaption of temperate fruit trees under tropical and subtropical environments. Some of these models and their uses are described in the final section of this review. In conclusion, global warming has led to chill deficit during winter, which may become a limiting factor in the near future for the growth of temperate fruit trees in the tropics and subtropics. With the increasing rate of climate change, improvements in some managing tools (e.g., discovering new, more effective dormancy breaking organic compounds; breeding new, climate-smart cultivars in order to solve problems associated with dormancy and chilling requirements; and improving dormancy and chilling forecasting models) have the potential to solve the challenges of dormancy and chilling requirements for temperate fruit tree production in warm winter fruit tree growing regions.

Efficiency of biologization of intensification processes in industrial fruit growing

The intensification processes characteristic in industrial fruit growing is given, their aims are determined. The main technological shifts of the technological structure formed in the domestic fruit growing are presented. Based on the analysis of the technological structure development, the predicted technological shifts for the near future, the characteristic features of promising technologies in the fruit growing, their criteria and signs are presented. The factors-indicators of fruit growing intensification are systematically presented. A retrospective of the industrial fruit growing intensification based on the weak-growing rootstocks breeding and introduction and differentiated technologies formed with their participation is reflected. The main directions of intensification that increase the agrocenosis biopotential are graphically presented. The analysis of chemical and technogenic factors negative impact on agroecocenoses leading to bioresource deformations in the biocenosis, soil and soil microbiota, microbio-, acaro- and entomosystems is carried out. The necessity of restoring and developing the reproductive capabilities of agroecosystems, mainly by biological methods, is proved, which include: the development of rhizosphere microorganism populations in the soil biota, the range expansion of the applied bioproducts created on the effective strain basis of beneficial microorganisms, the widespread application of various forms and methods to increase plant immunity, including elicitor-type preparations.

Increasing the technological and economic efficiency of nursery production based on processes biologization

The necessity of reformatting the structural organization of processes, which determines the priority of using the ways, forms and methods of the sixth technological structure, in particular, biotechnologies is actualized. The main definitions are given: nursery, biologization, greening, resource saving, promising technology. The analysis of the efficiency of sapling fruit production, the structural organization of specific processes for the production of planting material and sapling is presented. The main elements of the agrocenosis, which are most susceptible to chemical and technogenic effects, have been determined. The analysis of soil fertility and the state of soil biota is carried out, the problem of microbiological processes branch in all agrocenosis elements is actualized. It was found that the increased chemical load on the agrocenosis of the fruit nursery led to the destruction of microflora useful species. The nature of plant organs infection has changed, and negative changes have occurred in the plants immune status. The priority role of biologization in ensuring the stability of the fruit nursery agrocenosis has been substantiated.

The genetic-selection improvement of approaches to the study of the fruit cultures adaptation to the stresses of the spring and summer period

The happening global and local fluctuations of climate caused the changes in manifestation of the temperature stresses in the plants in terms of their strength and time of occurrence in vegetation period. The most regions of the south of Russia (especially in the plain territories) experienced warming of climate, and the temperature stresses began to appear more frequently in spring and in summer. With an aim to analyze the direction of change in temperature regime the structure and spectrums of variability in the mean-diurnal fluctuations of the maximum and minimum temperatures of air were studied for a long period (1950-2019) in the Kuban river horticulture zone of Krasnodar Territory. The defense and adaptive reactions of the sweet cherry varieties (in their drought resistance) to the change in external environment limits were brought to light. The yielding capacity of the genotypes of plants was studied from position of their response to the temperature stresses. The obtained results permitted to identify the varieties of sweet cherry, resistant to the stresses of the spring and summer period, when they are grown in conditions of the higher temperatures and considerable moisture deficit. The results of work will be helpful in control of the sweet cherry varieties productivity on the basis of knowledge on manifestation of the varieties’ genetic peculiarities in their phenotype in the new climatic conditions.