Search

Salinity has emerged as a critical abiotic stress factor, significantly limiting the growth, productivity, and quality of many crop species. As the global salinization of agricultural land continues to intensify, it is crucial to explore effective mitigation strategies to sustain crop yields. γ-Aminobutyric acid (GABA), a non-protein amino acid, is present in a variety of organisms, including plants, where it fulfills diverse roles under both optimal and stress conditions. In plants, GABA is intricately involved in nitrogen metabolism, amino acid biosynthesis, and the regulation of primary and secondary metabolic pathways. Functioning through the GABA shunt, it provides the carbon skeletons and energy required for biosynthetic processes and is vital for the regulation of carbon and nitrogen balance. Under abiotic stress conditions, particularly salinity, GABA rapidly accumulates, facilitating several protective mechanisms that help plants cope with stress. These include enhancing osmotic adjustment through the accumulation of osmolytes, protecting cellular structures such as chloroplasts, and improving chlorophyll fluorescence and photosynthetic efficiency. Moreover, GABA has been shown to boost antioxidant enzyme activity, reducing oxidative stress and mitigating the damage caused by reactive oxygen species (ROS) under salinity conditions. This study explores the multifaceted role of GABA in plants under saline environments, with a focus on its physiological, biochemical, and molecular mechanisms in enhancing plant resilience. By elucidating these mechanisms, we aim to highlight the potential of GABA as a natural biostimulant to improve crop performance and sustainability in saline soils. [ABSTRACT FROM AUTHOR]

Apricot fruit are characterised by limited post-harvest storability, this study aimed to evaluate the effectiveness and the interplay between psyllium treatment as a coating application method and 1-(3-phenyl-propyl) cyclopropene (1-PCP) as an ethylene inhibitor in enhancing the storability of apricot fruit during storage at 3°C and 90% relative humidity for 32 d. All treatments impacted fruit quality and storability in 'Canino' apricots. The combined application of both compounds led to a substantial reduction in fruit decay rate, weight loss, malondialdehyde content, and H2O2 levels. Furthermore, it contributed to improved fruit colouration and TSS content. Both psyllium and 1-PCP treatments, whether applied individually or in combination, notably reduced respiration rates, ethylene production, and the activity of key enzymes involved in ethylene biosynthesis (ACC-synthase and ACC-oxidase) when compared to the control group. Moreover, these treatments reduced oxidative stress, by affecting phenolic content, flavonoids, and antioxidant levels (both hydrophilic and lipophilic antioxidant capacity). Additionally, these treatments regulated related enzymes activities such as catalase, peroxidase, superoxide dismutase, and phenylalanine-ammonia lyase. Hence, it is recommended to utilise psyllium and 1-PCP to enhance the storability of apricot fruit while maintaining their overall quality. [ABSTRACT FROM AUTHOR]

This study evaluates the projected impact of climate change on wheat production in Northwest Tunisia, specifically at Medjez El Beb (36.67 m, 9.74°) and Slougia (36.66 m, 9.6°), for the period 2041–2070. Using the CNRM-CM5.1 and GFDL-ESM2M climate models under RCP4.5 and RCP8.5 scenarios, coupled with the AquaCrop and SIMPLE crop growth models, we compared model outputs with observed data from 2016 to 2020 to assess model performance. The objective was to determine how different climate models and scenarios affect wheat yields, biomass, and growth duration. Under RCP4.5, projected average yields are 7.709 q/ha with AquaCrop and 7.703 q/ha with GFDL-ESM2M. Under RCP8.5, yields are 7.765 tons/ha with AquaCrop and 7.198 q/ha with SIMPLE Crop, indicating that reduced emissions could improve wheat growth conditions. Biomass predictions showed significant variation: in Medjez El Beb, average biomass is 17.99 tons/ha with AquaCrop and 18.73 tons/ha with SIMPLE Crop under RCP8.5. In Slougia, average biomass is 18.90 tons/ha with AquaCrop and 19.04 tons/ha with SIMPLE Crop under the same scenario. Growth duration varied, with AquaCrop predicting 175 days in Medjez El Beb and 178 days in Slougia, while SIMPLE Crop predicted 180 days in Medjez El Beb and 182 days in Slougia, with a standard deviation of ±12 days for both models. SIMPLE Crop demonstrated higher accuracy in predicting growth cycle duration and yield, particularly in Slougia, with mean bias errors of −3.6 days and 2.26 q/ha. Conversely, AquaCrop excelled in biomass prediction with an agreement index of 0.97 at Slougia. Statistical analysis revealed significant yield differences based on climate models and emission scenarios, with GFDL-ESM2M under RCP4.5 showing more favorable conditions. These findings emphasize the importance of model selection and calibration for accurately projecting the agricultural impacts of climate change, and they provide insights for enhancing prediction accuracy and informing adaptation strategies for sustainable wheat production in Northwest Tunisia. [ABSTRACT FROM AUTHOR]

Salinity stress is an alarming issue causing a substantial reduction in crop productivity. Waterlogging also limits crop productivity and the extent of both these stresses is increasing due to climate change and global warming. This study investigated the response of Lemongrass and Asparagus grass under salinity stress and waterlogged conditions. The study was comprised of different treatments: control, salinity stress, waterlogged conditions and salinity stress + waterlogged conditions. The results revealed that salinity + waterlogging pressure negatively affected cymbopogan citratus and Asparagus officinalis. The physio-morphological, biochemical attributes, enzymatic antioxidants, and nutrient parameters showed a greater reduction under combined salinity and water waterlogged conditions. Waterlogging caused a marked decrease in root growth, leaves production and plant height of both grasses, compared to the control. Salinity stress also resulted in similar morphological modifications, albeit to a lesser extent. Physiological analysis showed a decline in chlorophyll content and RWC, indicating reduced photosynthetic capacity and water uptake efficiency in response to waterlogging and salinity. Electrolyte leakage, increased significantly under waterlogging and salinity stress, suggesting cellular damage and membrane disruption. C.citratus exhibited greater resilience to waterlogging and salinity compared to A. officinalis. Despite the adverse conditions, C. citratus maintained higher chlorophyll content, RWC, and lower electrolyte leakage, indicating better stress tolerance mechanisms. In conclusion, waterlogging and salinity induced significant morphophysiological modifications in both C. citratus and A. officinalis. However, C. citratus exhibited better tolerance to these stresses, suggesting its potential for cultivation in waterlogged and saline environments. [ABSTRACT FROM AUTHOR]

This study focuses on the assessment of the impact of climate change on the efficiency of ambient air aeration and the dynamics of Rhyzopertha dominica, which is a major pest that infests wheat stored in Tunisia. To project future climate conditions for the period 2041–2070, two climate models, namely MPI-ESM1.2 and CNRMCM5.1, were used under two representative concentration pathways (RCP4.5 and RCP8.5). The study examined the historical and projected feasibility of aeration in six natural regions located in northwestern Tunisia, where wheat is the main crop, and investigated the potential consequences of climate change on the dynamics of R. dominica. Using a heat and mass transfer model in an unaerated wheat silo, the temperature and moisture distributions in the grain mass were used to predict the development, reproduction, and survival of R. dominica. The results revealed a decline in favorable aeration hours due to climate change, resulting in an average reduction of 25% across the six regions. This reduction in aerated hours could significantly affect the effectiveness of aeration as a means of pest control. The mean difference comparisons, based on Tukey's honestly significant difference (HSD) test, revealed a significant effect of climate change on the developmental parameters of R. dominica for the period 2041–2070 compared to the period 1970–1997. According to the insect dynamic model, future climate scenarios are expected to induce changes in the development duration, reproduction, and survival rates of R. dominica. The model predicts a (i) 10–15% extension in the development duration, (ii) 20–30% decrease in reproduction, and (iii) 5–10% decrease in survival relative to the historical period. These results underscore the critical importance of implementing adaptive pest management strategies for stored wheat. [ABSTRACT FROM AUTHOR]

Maize (Zea mays L.) is a significant global staple crop, which is important for its nutritional and economic value. However, the negative effects of drought and chilling stress, induced by climate change, are rapidly increasing threats to compromise its healthy yield. The processes that are affected by chilling stress are reduced growth, impaired photosynthesis, increased susceptibility to disease and pests, late flowering and reduced leaf size. Growth components of plants such as gibberellic acid, calcium, abscisic acid and salicylic acid can control the maize response to chilling stress. Conversely, drought stress, which is brought on by insufficient water availability, interferes with essential functions like the roots' ability to absorb water and nutrients, increases transpiration losses, causes the leaves to roll, and delays senescence. To improve drought tolerance ability in maize, glycine betaine, potassium and foliar calcium spray are worthwhile. Events that combine freezing and drought present a difficult challenge and reduce maize productivity. Reduced yields of maize not only place food security at risk, but also have severe economic implications on farmers and countries that depend mainly on maize production. Implementing proactive approaches, including as breeding initiatives, precision agriculture, water management, farming systems can present workable ways to minimize the impacts these stresses and defend maize production under prevailing fluctuating environment. This review highlights the most recent findings on the impact of drought and cold weather on corn plants. Potential management strategies for regulating plant tolerance mechanisms to drought and cold stress are also outlined. [ABSTRACT FROM AUTHOR]