Declining Crop Yields Research Articles

Systematic Mapping of Climate Change Impacts on Human Security in Bangladesh

There is an increasing consensus that climate change undermines human security by exacerbating existing challenges, acting as a “threat multiplier”. Bangladesh is a climate hot spot due to its geographical location, dense population and vulnerable socio-economic infrastructure. Although there is an increasing number of studies on the impacts of climate change in Bangladesh, aggregated research that combines this evidence and provides a comprehensive overview is lacking. The aim of this research is to thoroughly investigate the characteristics of the academic literature on the complex pathways through which climate variability affects different components of human security in Bangladesh, allowing for determination of the trends and research gaps, as well as whether they lead to conflict or cooperation. We used a systematic mapping methodology to search and screen 1839 publications in Web of Science, including 320 publications for the final synthesis. We found a predominant research focus on rural areas, especially in the southwestern region, with declining crop yield, economic loss, migration, water shortage, food scarcity and health hazards being the highlighted impacts of climate change for Bangladesh. The impacts on food, economic, environmental, health and water security have been well studied, but we found significant research gaps in some human security components, especially energy security. Women and the economically disadvantaged are disproportionately affected, and the causal pathways between conflict or cooperation and the ever-changing climate lack research efforts, implying a dire need to focus on under-researched areas before they become more complex and difficult to address. Policies and interventions should prioritise climate-resilient agricultural practices and infrastructure in high-risk areas, building local capacities and integrating climate risk assessments into urban planning, considering the high influx of environmental migrants. This systematic map provides a foundation for future longitudinal studies, establishes a baseline for this era for future comparisons and serves as a reliable database for relevant stakeholders and policy makers.

Exogenously applied silver nanoparticles (AgNPs) differentially affect bacterial blight disease control in twenty-seven wheat cultivars

The bacterial blight of wheat is an important global disease causing a significant decline in crop yield. Nanotechnology offers a potential solution for managing plant diseases. Therefore, this research aimed to investigate the effectiveness of silver nanoparticles (AgNPs) in controlling bacterial blight in 27 locally grown wheat cultivars. The study examined the impact of AgNPs at three distinct time points: 1, 3, and 5 days after the onset of the disease. Biochemical assay revealed that one day after applying the disease stress, the Inia cultivar had the highest amount of soluble protein (55.60 μg.g−1FW) content in the treatment without AgNPs. The Azadi cultivar, without AgNPs treatment, had the lowest amount of soluble protein content (15.71 μg.g−1FW). The Tabasi cultivar had the highest activity of the superoxide dismutase (SOD) (61.62 mM.g−1FW) with the combination treatment of AgNPs. On the other hand, the Karchia cultivar had the lowest SOD activity (0.6 mM.g−1FW) in the treatment of disease without AgNPs. Furthermore, three days after the application of stress, the Mahdavi cultivar had the highest amount of soluble protein content (54.16 μg.g−1FW) in the treatment of disease without AgNPs. The Niknejad cultivar had the highest activity of the SOD (74.15 mM.g−1FW) with the combined treatment of the disease without AgNPs. The Kavir cultivar had the lowest SOD activity (1.95 mM.g−1FW) and the lowest peroxidase (POX) activity (0.241 mM g−1FW min−1) in the treatment of the disease with AgNPs. Five days after exposure to stress, the Mahooti cultivar had the highest SOD activity (88.12 mM.g−1FW) with the combined treatment of the disease with AgNPs, and the Karchia cultivar had the lowest SOD activity (2.39 mM.g−1FW) in the treatment of the disease with AgNPs. Further, the results indicated that exposure to AgNPs could improve the antioxidant properties of wheat seeds in blight-infected and disease-free conditions in some cultivars.

Assessment of soil erosion risk in a hilly zone sub-watershed of Karnataka using geospatial technologies and the RUSLE model

ABSTRACT Human activities and climate change have sped up soil erosion, leading to annual losses of fertile soil and declining crop yields. The biggest concerns in land and water conservation are modeling and monitoring soil loss, as well as measuring the vulnerability and danger of active erosional processes. In the present study, a comprehensive approach used to evaluate the risk of soil erosion in the Ganjigatti sub-watershed of Karnataka, India, using the RUSLE model and GIS techniques. The annual average soil loss estimated using the RUSLE model ranged from 0 to 122.73 t ha−1 yr−1, with an average of 3.48 t ha−1 yr−1 in the Ganjigatti sub-watershed. The quantity of erosion was found to be greatly influenced by topography (LS factor) and land use and land cover (C factor). The results showed that a larger part of the study area, 98.34%, accounted for slight erosion (0–5 t ha−1 yr−1). The spatial pattern of erosion revealed high to very severe risk zones in the main stream of sub-watershed. The total soil loss was calculated to be 15,046.96 t yr−1 in the sub-watershed. The study’s results aid decision-makers, land administrators, environmentalists, and others in implementing effective land and water conservation measures in the Ganjigatti sub-watershed to control soil erosion.

Perceived Effects of Climate Variability on Crop Production in Imo State, Nigeria

This study assessed the effect of climate variability on crop production in Imo State, Nigeria. Climate variability has direct impacts that cause vulnerability to the natural and social systems through changes in average temperatures, temperature extremes and extreme weather events like flooding and droughts. The study described the socio-economic characteristics of the crop farmers, ascertained crop farmers’ knowledge on climate variability, determined the perception of farmers on climate variability, and examined the perceived effects of climate variability on food crop yield production. A multistage sampling procedure was used in the selection of one hundred and eighty-three (183) crop-based farmers. Structured questionnaires were used in obtaining data and the data collected were analyzed using frequency, percentage, mean score and multiple regression analysis. Findings show that the mean age was 48.77 years. Majority (71.58%) were females. Majority (78.14%) were married with an average household size of 8 persons. Most (65.57%) had secondary education with an average farming experience of 21.18 years. Average farm size and farm income were 1.24 hectares and ₦33,000.00 respectively. Findings show that farmers had major knowledge of climate variability as zero/minimum tillage practices (99.45%) and knowledge on rain-water harvesting (97.81%) amongst others. Farmers perceived climate variability (x̄ = 3.49), starts late and ends early (x̄ = 3.45), extremes in temperatures (x̄ = 3.39), too much/heavy rains (x̄ = 3.396) and long dry spells during the season (x̄ = 3.51), amongst others. Crop farmers further perceived that climate variability has resulted in declining crop yields (x̄ = 3.35), increased water scarcity on farm (x̄ = 3.45), high incidences of pest and diseases (x̄ = 3.29), and increased rate of erosion/flooding (x̄ = 3.50) amongst others. The study strongly recommends that the extension services should be strengthened so as to pay farmers regular visits to ascertain their challenges on the effects of climate variability and know where to assist them.

Human-Wildlife Conflicts in a Changing Climate Regime: A Multidimensional Perspective In Swagaswaga Game Reserve, Tanzania

This study examines the influence of climatic and non-climatic factors on human- wildlife conflicts in Swagaswaga Game Reserve, Tanzania. A mixed research design employing both qualitative and quantitative data collection methods -- including semi-structured interviews, focus group discussions, and key informant interviews -- was used. Rainfall and temperature data for the past 30 years was obtained from the Tanzania Meteorological Authority. Quantitative data was analysed using IBM SPSS (V26), in which the Chi-square test was performed to test the association between predictors and the status of human-wildlife conflicts. A binary logistic regression model was used to determine the extent to which independent factors were associated with human-wildlife conflicts. Meteorological data on rainfall and temperature was analysed using Excel to perform a simple regression analysis. Qualitative data was analysed using the content analysis technique. The study revealed that both climatic and non-climatic factors influenced conflicts. As temperature increased significantly, evapotranspiration and scarcity of resources also increased, leading to a decline in crop yield, accelerated human-wildlife conflicts due to resource competition between wildlife and communities around protected areas. Rainfall distribution, onset, and cessation were unpredictable. Additionally, human-wildlife conflict is significantly associated with human population growth, while encroachment and reserve expansion influenced human-wildlife conflicts, though their impacts were not significant. Conclusively, climate change and rapid human population growth accelerated encroachment, causing wildlife survival threats and intensifying human-wildlife conflicts. The study recommends that the government should develop a comprehensive land use plan involving local communities in decision- making to adapt to the impacts of climate change on wildlife habitats and livelihoods.

Physiological, biochemical and transcriptomic insights into the mechanisms by which molybdenum mitigates cadmium toxicity in Triticum aestivum L

There are many heavy metal stresses in agricultural biological systems, especially cadmium (Cd) stress, which prevent the full growth of plants, lead to a serious decline in crop yield, and endanger human health. Molybdenum (Mo), an essential nutrient element for plants, regulates plant growth mainly by reducing the absorption of heavy metals and protecting plants from oxidative damage. The aim of this study was to determine the protective effect of Mo (1 μM) application on wheat plants under conditions of Cd (10 μM) toxicity. The biomass, Cd and Mo contents, photosynthesis, leaf and root ultrastructure, antioxidant system, and active oxygen content of the wheat plants were determined. Mo increased the total chlorophyll content of wheat leaves by 43.02% and the net photosynthetic rate by 38.67%, and ameliorated the inhibitory effect of cadmium on photosynthesis by up-regulating photosynthesis-related genes and light-trapping genes. In addition, Mo reduced the content of superoxide anion (O2•—) by 16.55% and 31.12%, malondialdehyde (MDA) by 20.75% and 7.17%, hydrogen peroxide (H2O2) by 24.69% and 8.17%, and electrolyte leakage (EL) by 27.59% and 16.82% in wheat leaves and roots, respectively, and enhanced the antioxidant system to reduce the burst of reactive oxygen species and alleviate the damage of Cd stress on wheat. According to the above results, Mo is considered a plant essential nutrient that enhances Cd tolerance in wheat by limiting the absorption, accumulation and transport of Cd and by regulating antioxidant defence mechanisms. Environmental ImplicationCadmium (Cd)，is one of the most toxic heavy metals in the environment, and Cd pollution is a global environmental problem that threatens food security and human health. Molybdenum (Mo), as an essential plant nutrient, is often used to resist environmental stress. However, the mechanism of Mo treatment on wheat subjected to Cd stress has not been reported. In this study, we systematically analysed the effects of Mo on the phenotype, physiology, biochemistry, ultrastructure and Cd content of wheat subjected to Cd stress, and comprehensively analysed the transcriptomics. It not only reveals the mechanism of Mo tolerance to Cd stress in wheat, but also provides new insights into phytoremediation and plant growth in Cd-contaminated soil.

Assessing soil erosion and farmers’ decision of reducing erosion for sustainable soil and water conservation in Burji woreda, southern Ethiopia

Inadequate conservation practice affects the sustainable production of agricultural watersheds due to erosion and fertility decline. Understanding soil erosion and implementing site-specific conservation practice could enhance agriculture-based rural development. The study was aimed to document soil erosion problem and soil and water conservation effort. The specific objectives of this study were to assess soil erosion severity, practices to reduce erosion, and determinants of the decision to reduce erosion. Data were collected by interviewing 198 farm household heads, undertaking four focus group discussions, and assessing rill erosion in 10 farm fields in Morayo and Wacho sub-watersheds of southern Ethiopia. Descriptive statistics and binary logit model were applied to analyze the data. Results indicated that many of the farm households, 63% in Morayo and 83% in the Wacho sub-watershed, perceived moderate to severe soil erosion, which is characterized by big rills and small gullies on the farmlands. Rill densities of 231.4 m ha−1 and 84.1 m ha−1 in the Morayo and Wacho sub-watersheds were observed, respectively. The estimated annual soil loss due to rills was 61.2 and 23.4 Mg ha−1 in the Morayo and Wacho sub-watersheds, respectively. The soil erosion from rills alone exceeds the expected tolerable soil erosion (11 tons ha−1 year−1). Due to erosion, about 90% of farmers perceived farmland degradation as described by a progressive decline in crop yield. Farmers used to practice traditional techniques to reduce erosion and government introduced conservation measures such as soil and stone bunds. However, many farmers did not use well-promoted conservation measures such as bunds, which could have negative impact on long-term erosion control effort and sustainable implementation of the conservation options. Among the assessed explanatory variables, educational level, farm distance from home, slope of the cultivated land, and frequency of extension contact were significantly affected (p < 0.05) farmers’ sustainable use of conservation measures. Development planners and policy makers are advised to consider site-specific and innovative approaches to implement conservation measures in sustainable approach in the smallholder crop-livestock mixed agriculture system.

Examining the effect of different photovoltaic modules on cucumber crops in a greenhouse agrivoltaic system: A case study

Agrivoltaic systems, a fusion of agriculture and photovoltaic (PV) technology, have emerged as a sustainable solution to optimise land use by enabling simultaneous solar energy and agricultural harvesting. The experiments were conducted in a polytunnel greenhouse in Kfar Qara, Israel, deploying three types of semi-transparent solar PV panels—bifacial glass-encapsulated silicon, bifacial plastic-encapsulated silicon, and semi-transparent organic photovoltaics (OPVs) installed above the plant canopy. The impact of these PV treatments on cucumber crops was evaluated and juxtaposed against a control greenhouse with no panels, over the spring season from February to June 2022. Key growth and yield metrics were recorded during 17 harvests between April 10 and June 2, 2022. The findings revealed a negligible decline in crop yield across PV panel treatments compared to the control. Notably, the control and glass-encapsulated silicon PV treatments demonstrated an increase in yield, growth, and fruit quality. Moreover, the glass-encapsulated silicon PV panels outperformed the plastic-encapsulated and OPV module power conversion in the high heat and humidity of the greenhouse environment. This study accentuates the potential of integrating glass-encapsulated silicon PV panels in polytunnel greenhouses, heralding a promising avenue for bolstering agrivoltaic applications by ensuring a harmonious balance between agricultural yield and electrical energy production.

Impact of biotic stresses on the Brassicaceae family and opportunities for crop improvement by exploiting genotyping traits.

Utilizing RNAi, miRNA, siRNA, lncRNA and exploiting genotyping traits can help safeguard the food supply from illnesses and pest damage to Brassicas, as well as reduce yield losses caused by plant pathogens and insect pests. In the natural environment, plants face significant challenges in the form of biotic stress, due to various living organisms, leading to biological stress and a sharp decline in crop yields. To cope with these effects, plants have evolved specialized mechanisms to mitigate these challenges. Plant stress tolerance and resistance are influenced by genes associated with stress-responsive pathogens that interact with various stress-related signaling pathway components. Plants employ diverse strategies and mechanisms to combat biological stress, involving a complex network of transcription factors that interact with specific cis-elements to regulate gene expression. Understanding both plant developmental and pathogenic disease resistance mechanisms can allow us to develop stress-tolerant and -resistant crops. Brassica genus includes commercially important crops, e.g., broccoli, cabbage, cauliflower, kale, and rapeseed, cultivated worldwide, with several applications, e.g., oil production, consumption, condiments, fodder, as well as medicinal ones. Indeed, in 2020, global production of vegetable Brassica reached 96.4 million tones, a 10.6% rise from the previous decade. Taking into account their commercial importance, coupled to the impact that pathogens can have in Brassica productivity, yield losses up to 60%, this work complies the major diseases caused due to fungal, bacterial, viral, and insects in Brassica species. The review is structured into three parts. In the first part, an overview is provided of the various pathogens affecting Brassica species, including fungi, bacteria, viruses, and insects. The second part delves into the exploration of defense mechanisms that Brassica plants encounter against these pathogens including secondary metabolites, duplicated genes, RNA interference (RNAi), miRNA (micro-RNA), siRNA (small interfering RNA), and lncRNA (long non-coding RNA). The final part comprehensively outlines the current applications of CRISPR/Cas9 technology aimed at enhancing crop quality. Taken collectively, this review will contribute to our enhanced understanding of these mechanisms and their role in the development of resistance in Brassica plants, thus supporting strategies to protect this crucial crop.

How Do Arable Crop Farmers’ Adapt to Climate Change? New Evidence from Nigeria

In Nigeria, climate change is not a new phenomenon and arable crop production is vulnerable to climate change. Arable crop farmers have always responded to climate change with local strategies believed to be climate-smart. Arable crop farmers' knowledge of climate change is an important step in understanding any action to be taken to reduce its effect. However, empirical studies on the link between climate change and crop farmers’ adaptation strategies are still relatively scanty in the area. This presents a dearth in research. Therefore, our paper examined how arable crop farmers adapt to climate change using cross-sectional data obtained through a structured focused group discussion and questionnaire from 120 arable farmers across critical farming communities in Imo State, Nigeria. We utilized multistage and purposive sampling procedure in the selection of arable crop farmers. The reason we utilized purposive sampling procedure was to select areas with high intensity of arable crop farmers and farming. Data collected was analyzed using descriptive statistical tools and mean (x̄) score analysis. Our result shows that the mean age was 42.00 years. Greater proportions (73.00%) were female. The average farm size was 1.45 hectares. Vegetables (100.00%), maize (99.17%), cassava (98.33%) and rice (96.67%) were among the crops produced in the area. The result confirmed the incidence of climate change in the area and farmers perceived rightly the direction of the change, which includes declining crop yields (x̄ = 3.00; σ = 0.50), increased in new pests and diseases infestation (x̄= 2.88; σ = 0.58); unstable decrease and increase in temperature and rainfall (x̄=3.63, σ = 0.83) among others. Our study further shows that the major climate change adaptation measures farmers practiced were diversification of livelihood (99.17%) and changing planting/harvesting dates (97.50%). Farmers identified inadequate information (99.17) and inadequate climate change adaptation fund (98.33%) among others as the barriers they faced in adapting to climate change in the area. We recommend that, since arable crop farmers are members of cooperatives, they are encouraged to take advantage of their strength to collectively project a common demand in obtaining funds and other necessary inputs in adapting to climate change in the area. Finally, our study also suggests that the agricultural extension service system should be strengthened so as to provide farmers with stable and right early warning signs which will be critical in minimizing risks of climatic threats in the area.

Climate change vulnerability of tribe managing Piper agroforestry systems in the Indian sub-Himalayan region

CONTEXTThe agrarian society of the Himalayan landscape is experiencing the continuous growing ill impact of climate change. The impacts are compounding due to shifting agriculture, which has jeopardized the ecological balance mainly by reducing the cultivation fallow cycles. Pnar, a hill tribe of the Assam state, Indian sub-Himalayan region, has transitioned shifting agriculture to Piper agroforestry (Piper betle L.), providing them numerous tangible and non-tangible benefits. Over the past three decades, there has been a notable transition from shifting agriculture to Piper agroforestry, driven by the rising demand in the market. OBJECTIVEUnderstanding climate change impact on agroforestry is crucial to addressing the climate crisis and to provision the adaptation of the tribe for the successful promotion of Piper agroforestry. METHODSTo assess the cause and nature of vulnerability in the study region, we surveyed 171 randomly selected households across 15 randomly selected tribe villages using the household-level questionnaire. RESULTS AND CONCLUSIONThe present study showed that the villages with lower land holdings, higher loss of crop productivity due to extreme events, disease infestation and lower livelihood diversification were more vulnerable to climate change. The prominent diseases “leaf spot” and “root rot” were identified as a serious concern among the Piper farmers responsible for a decline in crop yield; the severity of losses in productivity leads to economic instability among households. Villages with prominent farm management strategies and greater decision-making abilities contributed explicitly to lower vulnerability. In contrast, villages with lower adaptive strategies were found specifically due to poor social networking and inadequate household infrastructure besides poor literacy levels. Additionally, the lack of multi-cropping farming and livestock management was a major cause of high climate sensitivity. Therefore, appropriate state government support is required to invest in crop diversification, better decision-making capability of tribes through education, and improved infrastructure besides diversifying the rural economy to enhance the adaptive capacity of the farmers to reduce their climate vulnerability and achieve agriculture-livestock-forestry nexus. SIGNIFICANCEThe sustainable Piper agroforestry farm management practices represent climate-smart agriculture, favouring high tree species diversity while reducing the farmers' vulnerability to climate change.

Ability of Nutrient Management and Molecular Physiology Advancements to Overcome Abiotic Stress: A Study on Sub-Saharan African Crops

Abiotic stress is a major cause of the declining crop yield worldwide, especially in tropical agricultural areas. Meeting the global food demand has become a serious challenge, especially in tropical areas, because of soil acidity, Al and Fe toxicity, drought and heat stress, and climate change. In this article, we reviewed several research and review papers from Google Scholar to list the different solutions available for the mitigation of abiotic stress, especially in tropical regions where several major crops, such as maize, sorghum, wheat, rice, soybean, and millet, are affected by abiotic stress and fertilizer input. In particular, Sub-Saharan Africa (SSA) has been affected by the low use of fertilizers owing to their high cost. Therefore, soil and plant researchers and farmers have developed many techniques to mitigate the effects of stress and improve the crop yield based on the agroecological zone and crop type. Nutrient management using chemical fertilizers alone or in combination with organic crops is a strategy recommended to cope with abiotic stress and increase the crop yield, particularly in developing countries. Notably, integrated soil fertility management has been effective in semi-arid areas under drought and heat stress and in subhumid and humid areas with high soil acidity and Fe toxicity in Africa. Recent advances in the molecular physiology of various crops considered a staple food in SSA have facilitated the breeding of transgenic tolerant plants with high yield. However, the feasibility and implementation of this technique in the African continent and most tropical developing countries are major issues that can be solved via adequate subsidies and support to farmers. This review can aid in the development of novel strategies to decrease hunger and food insecurity in SSA.

Optimalisasi Citra Termal dalam Pertanian Presisi untuk Deteksi Dini Masalah Kesehatan Bibit Kelapa Sawit

The palm oil industry plays a pivotal role in various sectors, including food and bioenergy. The success of oil palm cultivation relies heavily on the health of the plant's seedlings. Early detection of diseases and stress is crucial to prevent a decline in crop yields and financial losses. Infrared Thermography technology has been widely employed across various fields for non-destructive monitoring, including agriculture. This research focuses on optimizing the use of thermal imaging in precision agriculture to early detect health issues in oil palm seedlings. Thermal imaging enables the precise measurement of plant surface temperatures, facilitating the identification of plant health issues without the need for further visual intervention. This study has the potential to transform approaches to proactively monitoring and managing the health of oil palm plants. Infrared thermography technology is utilized to observe temperature distribution patterns in oil palm seedlings. The objective is to explore the correlation between thermal characteristics and potential health issues or symptoms in these seedlings. Samples used in the research involve Tenera variety oil palm seedlings aged between 5-9 months, a critical growth phase. The study employs the UNI-T UTi120 Mobile thermal camera capable of measuring temperatures ranging from -20°C to 400°C. Subsequently, thermal image processing is conducted to identify thermal characteristics that could serve as indicators of health issues in oil palm seedlings. Statistical analysis is then performed to test significant differences in thermal characteristics between healthy and unhealthy plant samples. The analysis results reveal significant temperature variations between healthy and unhealthy portions of the plant seedlings, with a significance value of 0,025. These findings can serve as a basis for identifying temperature changes as potential early indicators of health issues in oil palm seedlings. This provides a foundation for developing more effective precision agriculture approaches within the palm oil industry.

Farmer’s Perception and Efficacy of Adaptation Strategies to Climate Change in North Eastern Transition Zone of Karnataka State in India

A primary survey during the year 2021-22 was carried out among the 240 farmers of Bidar and Gulbarga districts of North Eastern Transition Zone in Karnataka to study the farmer’s perception on climate change for the period 1979 to 2019 and validate their opinions with the change in the meteorological indicators. About 74 percent of farmers expressed that there is a decline in crop yield while 83 percent of farmers opined that is a shift of employment from farm to non-farm activities during the period of forty years. Farmers practice various farm adaptation strategies activities to overcome the effect of climate change. Through Garatte ranking, it is revealed that most of the farmers prefer to practice alteration of sowing dates of crop (rank 1) as adaptation strategy followed by using of drought tolerant varieties (rank 2) and mixed cropping (rank3). Binary Logit analysis was used to identify the socio- economic attributes of households influencing the adoption of adaptation strategy to climate change. The results showed that, the variables like farm size, access to institutional credit, live stock ownership and climate information are the factors which positively shows significant influence on adoption. Economic incentives play an important role in the adoption of modern technologies. Access to institutional credit will support the farmers financially in adopting water conservation techniques like farm ponds, micro irrigation products.

Efficient agricultural practices in Africa reduce crop water footprint despite climate change, but rely on blue water resources

Alarming projections of climate change, decline in crop yields, and increased food demand constitute daunting threats to African food production and sustainable water management. Here, we map this complex water-food nexus by combining gridded climate data and process-based crop modelling to quantify scenarios of crop water footprint under Representative Concentration Pathway 2.6 and Representative Concentration Pathway 6.0 for time horizons 2040, 2070 and 2100. We show that high-input agricultural management coupled with the expansion of irrigation infrastructure could generate an average reduction of water use intensity up to 64% for staple crops, but only 5% for cash crops, by 2040. Notwithstanding the positive effect of intensification, between 82 Km3 (2040) and 102 Km3 (2100) of additional blue water will be required to sustain the increased yields. Our scenarios are suited for identifying locations where crops are subject to high climate impacts and where crop production shows trade-offs between high-input management and irrigation demand.

Hyperaccumulator Solanum nigrum L. Intercropping Reduced Rice Cadmium Uptake under a High-Bed and Low-Ditch Planting System

Anthropogenic activities have raised cadmium (Cd) concentrations in agricultural soil, emerging as a primary catalyst for the decline in crop yield. Intercropping of two or several plants is one technique among many Cd phytoremediation techniques that has gained enormous attention recently. However, the impact of cultivation modes on Cd movement in rice plants when intercropped with heavy metal (HM) hyperaccumulator plants remains unclear. Thus, this study was designed to explore the effects of cultivation modes and the intercropping of rice with Solanum nigrum L. on rice growth and Cd uptake in Cd-contaminated soil. The experimental design encompassed five treatments: dry cultivation of monocultured rice, monocultured Solanum nigrum L., and intercropped rice–Solanum nigrum L.; flood cultivation of monocultured rice; and intercropped rice–Solanum nigrum L. in a high-bed and low-ditch planting system. The results revealed a significant increase in rice growth when intercropped with Solanum nigrum L., with a notable increase of 18.32 g∙plant−1 observed in rice biomass in dry cultivation under the intercropping system. In contrast, a more modest increase of 3.67 g∙plant−1 was observed in the high-bed and low-ditch intercropped rice–Solanum nigrum L. mode. The soil total Cd was higher in dry cultivation of monocultured rice and Solanum nigrum L. compared to intercropped rice/Solanum nigrum L.-cultivated soil, with lower values recorded for intercropped rice/Solanum nigrum L. under the high-bed and low-ditch planting system. In contrast, no significant effect was noted on soil exchangeable Cd content based on the planting pattern and cultivation mode. Intercropping with Solanum nigrum L. demonstrated a significant reduction of Cd content in various rice tissues, particularly in roots at the maturity stage, while Cd content was reduced across all rice tissues under the high-bed and low-ditch planting system. The Cd content in the stem, leaves, and bran of monocropped rice was higher compared to intercropped rice. This study suggests that the rice–Solanum nigrum L. intercropping system effectively reduces rice Cd uptake, particularly under the high-bed and low-ditch planting system.

Perceptions of climate variability and change in coastal Kenya: The case of mangrove-dependent communities in the Lower Tana Delta

Climate change has become a global concern with substantial impacts in all regions, especially coastal communities. In response, coastal communities take different adaptation strategies to minimise the negative impacts of climate change. Understanding climate change from the perspective of local communities can provide valuable insights into policy and strategy planning for the unprecedented consequences of climate change. Data was gathered in three sub-locations through a questionnaire survey (365 households), four (4) focus group discussions (FGDs) and eleven (11) key informant interviews (KIIs). We also explored meteorological data to understand better the local significance of climate variability and climate change. Descriptive statistics and logistic regression were used to analyse the data. The results show that local communities perceived changes in climate variables, consistent with meteorological data, pointing to a significant decline in rainfall and increased temperatures since the 1980s. The communities also highlighted climate-related events such as floods, droughts, saltwater intrusion, and coastal erosion, expressing concern that these were rising. The perceived changes in the climatic variables have led to a decline in crop yields, fish catch, and water quantity, an increase in drought duration and intensity, and plant and animal diseases. Targeted efforts are required, given the likely magnitude of future climate change.

Comparative Transcriptome Analysis Reveals the Underlying Response Mechanism to Salt Stress in Maize Seedling Roots.

Crop growth and development can be impeded by salt stress, leading to a significant decline in crop yield and quality. This investigation performed a comparative analysis of the physiological responses of two maize inbred lines, namely L318 (CML115) and L323 (GEMS58), under salt-stress conditions. The results elucidated that CML115 exhibited higher salt tolerance compared with GEMS58. Transcriptome analysis of the root system revealed that DEGs shared by the two inbred lines were significantly enriched in the MAPK signaling pathway-plant and plant hormone signal transduction, which wield an instrumental role in orchestrating the maize response to salt-induced stress. Furthermore, the DEGs' exclusivity to salt-tolerant genotypes was associated with sugar metabolism pathways, and these unique DEGs may account for the disparities in salt tolerance between the two genotypes. Meanwhile, we investigated the dynamic global transcriptome in the root systems of seedlings at five time points after salt treatment and compared transcriptome data from different genotypes to examine the similarities and differences in salt tolerance mechanisms of different germplasms.

Integrating Chlorophyll a Fluorescence and Enzymatic Profiling to Reveal the Wheat Responses to Nano-ZnO Stress.

It has been shown that increased concentrations of zinc oxide nanoparticles (nano-ZnO) in the soil are harmful to plant growth. However, the sensitivity of different wheat cultivars to nano-ZnO stress is still unclear. To detect the physiological response process of wheat varieties with different tolerance to nano-ZnO stress, four wheat cultivars (viz., cv. TS1, ZM18, JM22, and LM6) with different responses to nano-ZnO stress were selected, depending on previous nano-ZnO stress trials with 120 wheat cultivars in China. The results found that nano-ZnO exposure reduced chlorophyll concentrations and photosynthetic electron transport efficiency, along with the depressed carbohydrate metabolism enzyme activities, and limited plant growth. Meanwhile, the genotypic variation in photosynthetic carbon assimilation under nano-ZnO stress was found in wheat plants. Wheat cv. JM22 and LM6 possessed relatively lower Zn concentrations and higher leaf nitrogen per area, less reductions in their net photosynthetic rate, a maximum quantum yield of the PS II (Fv/Fm), electron transport flux per cross-section (ETo/CSm), trapped energy flux per cross-section (TRo/CSm), and total soluble sugar and sucrose concentrations under nano-ZnO stress, showing a better tolerance to nano-ZnO stress than wheat cv. TS1 and ZM18. In addition, the chlorophyll a fluorescence parameters Fv/Fm, ETo/CSm, and TRo/CSm could be used to rapidly screen wheat varieties resistant to nano-ZnO stress. The results here provide a new approach for solving the issues of crop yield decline in regions polluted by heavy metal nanoparticles and promoting the sustainable utilization of farmland with heavy metal pollution.

The influence of soil-drying inputs on the soil and the productivity of crops

In Kazakhstan, agricultural land has been degraded for decades, leading to an overall decline in crop yields. The purpose of the study is to conduct an environmental assessment of the current state of Kazakhstan’s soils to increase crop yields using soil protection methods. The following methods were used in the study: cartographic, analysis and synthesis, systematization, abstraction, specification, and forecasting. Agriculture accounts for 86% of Kazakhstan’s land. Active land use has led to various forms of degradation, resulting in 90 million hectares of eroded soils, of which 29.3 million hectares are almost completely eroded. In 2023, the average yield of grain crops was 9.3 c/ha, oilseeds – 7.1 c/ha, and vegetables – 275.4 c/ha. It is noted that the yield of grain crops in 2023 is 28% lower than in the previous period of 2020-2022, despite the increase in sown areas. Drought and soil degradation are the main reasons for the decline in grain yields. It is noted that the main biological constraints to grain production are soil drought, windstorms, degradation and extreme temperatures, especially in rainfed irrigated farming systems in arid lands such as southern Kazakhstan. In the northern and central parts of Kazakhstan, agricultural land is dominated by black and chestnut soils, and in the south by brown semidesert soils. The largest areas of eroded agricultural land are located in Almaty, Atyrau and Turkestan regions – over 30%, and the smallest – in Akmola, Karaganda, Kostanay and North Kazakhstan regions – 5%. Productive grain growing requires soil monitoring for the main mobile elements that affect plant yields. The average values for the Republic of Kazakhstan are: nitrogen content – 37.5 mg/kg, phosphorus – 16.8 mg/kg, potassium – 419.5 mg/kg, humus – 2.8%. The practical significance of the study is to expand and supplement the theoretical basis of research in the field of soil degradation, and the results obtained are proposed for a comprehensive environmental assessment of soils in Kazakhstan