Agriculture In Semi-arid Regions Research Articles

A Detailed Proteomics and Metabolomics Landscape Sheds Light on the Mechanistic Insights Into the Resistance Response of Transgenic Pigeon Pea Against Wilt Stress.

Pigeon pea, vital for farmers in semi-arid regions, suffers yield losses from Fusarium wilt caused by Fusarium udum. This study demonstrates that introducing the rice oxalate oxidase 4 (Osoxo4) gene significantly boosts wilt resistance. Enhanced resistance in transgenic lines was confirmed through gene expression analysis, enzyme activity assays, biochemical assessments, histochemical staining and in vitro and in vivo bioassays, including spore germination tests. We performed proteomics and metabolomics analyses to investigate mechanisms of enhanced resistance. LC-MS/MS-based label-free proteomics of wilt-infected transgenic and wild-type pigeon pea leaves identified 2386 proteins, with 1048 showing significant abundance changes-738 upregulated and 310 downregulated-in transgenic plants. Notably, proteins such as HMG1/2-like protein, Putative nucleosome assembly protein C364.06, DEAD-box ATP-dependent RNA helicase 3, Lipoxygenase 1, Annexin D1 and Annexin-like protein RJ4 were significantly upregulated, indicating their potential role in developing wilt-resistant cultivars. Metabolomic analysis showed elevated levels of amino acids, sugars, oxalic acid, sugar alcohols and myo-inositol in transgenic pigeon pea, with upregulated pathways in Sugar and Starch Metabolism and Inositol Phosphate Metabolism, indicating enhanced resilience to wilt stress. This study highlights unique regulatory proteins and metabolites, offering insights into stress adaptation and guiding genetic interventions for breeding disease-resistant pigeon pea varieties.

Straw return can increase maize yield by regulating soil bacteria and improving soil properties in arid and semi-arid areas

Straw return has been found to benefit soil fertility and crop yield, however, by which it affects microbial communities to mediate soil factors driving crop yields under maize continuous cropping systems in dryland areas is still unclear. To fill this gap, a 6-year field experiment was established with five straw return amounts (T0, T1, T2, T3, and T4, representing 0, 3,000, 6,000, 9,000, and 12,000kgha-1 of straw, respectively), and investigated the effects of on soil properties, enzymes, bacterial community composition and diversity, and crop yields. Our analysis showed that soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) contents significantly increased by 1-8%, 5-25%, and 2-9% under straw return treatments, respectively, compared to the T0, and soil catalase, urease, and alkaline phosphatase activities increased by at least 34.00%. Additionally, crop yield significantly increased by 4.23-12.00% under T1-T4 treatments, and showed highly significant relationships with SOC, TN, and TP. Importantly, we found straw return significantly altered the community of bacteria involved in the carbon and nitrogen cycle, and their abundance of strong responses depending on the amounts of straw return. For example, straw input increased the abundance of Proteobacteria (+2.64–5.57%), Acidobacteria (+3.82–13.83%), and Bacteroidetes (+15.37–30.49%). Similarly, the amount of straw application increased the bacterial diversity indexes (Shannon, 2.65–10.93%; Chao1, 13.47–18.50%), and had significant positive correlations with SOC, TN, and TP contents. Structural equation models (SEM) revealed that straw return management practice had positive and indirect effects on crop yields by influencing soil properties or the bacteria community. In conclusion, our findings revealed common associations and variations of bacterial community diversity with soil factors and crop yields at different straw return rates, and these findings provide insights and options for the development of better straw return strategies and sustainable agriculture in semi-arid regions.

Pollen viability, stigma receptivity and reproduction mode of spineless cactus (Nopalea cochenillifera Salm-Dyck) accessions

Forage cactus (Opuntia spp. and Nopalea spp.) have great potential for animal feed and human consumption due to their adaptability to semi-arid conditions. This study evaluated six accessions of N. cochenillifera, analyzing pollen viability, stigma receptivity and reproduction mode. Four types of pollination were tested: spontaneous self-pollination, manual self-pollination, natural pollination and cross-pollination. The results indicated high pollen viability and stigma receptivity in some accessions during flower bud development, allowing for self-pollination and controlled hybridization. After 24 hours of anthesis, pollen viability decreased, but stigma receptivity reached 100%. Fruiting occurred via natural pollination in all accessions, and by self-pollination and cross-pollination in accessions ac-02 and ac-03, which showed a mixed reproductive system. These results are essential for breeding programs, contributing to sustainable agriculture in semi-arid regions.

Technology Intensification and Farmers’ Welfare: A Case Study from Karnataka, a Semi-arid State of India

Technology adoption has been advocated to be an important way to improve agricultural productivity and welfare of the farmers in the semi-arid regions across the globe. Government of Karnataka implemented Bhoosamrudhi programme in four districts of the state (Bidar, Chikballapur, Dharwad and Udupi) as a pilot project to increase the crop yield and income of smallholder farmers. This programme was launched on the theme of technology adoption, along with convergence among different departments of agriculture. Farmers have been classified into five categories based on their levels of technology intensification to assess the impact of different levels of technology intensification on their income level. The research is built on a primary survey conducted in pilot districts of the state in 2018 over a sample of 1,465 farmer households. The results are generated using econometric methods of propensity score matching (PSM) and inverse probability weighted with regression adjustment (IPWRA), which highlight that higher the intensification, higher the net returns to the farmers. The results state that non-adopters would benefit additional ₹3,200 per month if they adopt at least one level of technology intensification. Hence, this programme turned out to be a successful model for smallholder farmers in semi-arid region of India. Steps should be taken to maintain and expand the momentum of the adoption to ensure food and livelihood security in the economy. JEL Codes: Q16, Q54, Q55, C13

TabHLH27 orchestrates root growth and drought tolerance to enhance water use efficiency in wheat.

Cultivating high-yield wheat under limited water resources is crucial for sustainable agriculture in semiarid regions. Amid water scarcity, plants activate drought response signaling, yet the delicate balance between drought tolerance and development remains unclear. Through genome-wide association studies and transcriptome profiling, we identified a wheat atypical basic helix-loop-helix (bHLH) transcription factor (TF), TabHLH27-A1, as a promising quantitative trait locus candidate for both relative root dry weight and spikelet number per spike in wheat. TabHLH27-A1/B1/D1 knock-out reduced wheat drought tolerance, yield, and water use efficiency (WUE). TabHLH27-A1 exhibited rapid induction with polyethylene glycol (PEG) treatment, gradually declining over days. It activated stress response genes such as TaCBL8-B1 and TaCPI2-A1 while inhibiting root growth genes like TaSH15-B1 and TaWRKY70-B1 under short-term PEG stimulus. The distinct transcriptional regulation of TabHLH27-A1 involved diverse interacting factors such as TaABI3-D1 and TabZIP62-D1. Natural variations of TabHLH27-A1 influence its transcriptional responses to drought stress, with TabHLH27-A1Hap-II associated with stronger drought tolerance, larger root system, more spikelets, and higher WUE in wheat. Significantly, the excellent TabHLH27-A1Hap-II was selected during the breeding process in China, and introgression of TabHLH27-A1Hap-II allele improved drought tolerance and grain yield, especially under water-limited conditions. Our study highlights TabHLH27-A1's role in balancing root growth and drought tolerance, providing a genetic manipulation locus for enhancing WUE in wheat.

SOIL CORRECTION AND <i>Azospirillum brasilense</i>: STRATEGIES IN THE CULTIVATION OF MAIZE GENOTYPES IN SEMI-ARID REGIONS

The replacement of Caatinga by extensive agriculture has led to soil degradation in maize (Zea mays L.) growing areas. The objective of this study was to evaluate the effects of soil correction in association with Azospirillum brasiliense to replace nitrogen (N) fertilizer on the vegetative growth of two maize genotypes cultivated on degraded soil. The soil was collected in an area undergoing desertification in Irauçuba, Ceará state, Brazil. A 2x2x5 factorial experiment was carried out in blocks: two soil fertility levels (corrected and uncorrected soil in terms of fertility), two maize genotypes (BRS Caimbé and BRS Gorutuba), and five nitrogen sources (control, inoculation with A. brasilense, inoculation with A. brasilense + 50 kg ha-1 of N, 50 kg ha-1 of N, and 100 kg ha-1 of N). BRS Gorutuba genotype showed greater adaptability to the growing conditions evaluated. However, macronutrient concentration did not affect maize dry matter yield. The response of maize inoculated with A. brasiliense suggests the inoculation efficacy, supported by the N accumulation and the effect on plant growth. The dry matter yield in A. brasilense inoculated plants was equivalent to using N fertilizer. Therefore, the inoculation of BRS Gorutuba maize grown on degraded soil with A. brasilense is a promising alternative for farmers in semi-arid regions.

Integrated transcriptomic and metabolomic analyses reveals anthocyanin biosynthesis in leaf coloration of quinoa (Chenopodium quinoa Willd.)

BackgroundQuinoa leaves demonstrate a diverse array of colors, offering a potential enhancement to landscape aesthetics and the development of leisure-oriented sightseeing agriculture in semi-arid regions. This study utilized integrated transcriptomic and metabolomic analyses to investigate the mechanisms underlying anthocyanin synthesis in both emerald green and pink quinoa leaves.ResultsIntegrated transcriptomic and metabolomic analyses indicated that both flavonoid biosynthesis pathway (ko00941) and anthocyanin biosynthesis pathway (ko00942) were significantly associated with anthocyanin biosynthesis. Differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) were analyzed between the two germplasms during different developmental periods. Ten DEGs were verified using qRT-PCR, and the results were consistent with those of the transcriptomic sequencing. The elevated expression of phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), 4-coumarate CoA ligase (4CL) and Hydroxycinnamoyltransferase (HCT), as well as the reduced expression of flavanone 3-hydroxylase (F3H) and Flavonol synthase (FLS), likely cause pink leaf formation. In addition, bHLH14, WRKY46, and TGA indirectly affected the activities of CHS and 4CL, collectively regulating the levels of cyanidin 3-O-(3’’, 6’’-O-dimalonyl) glucoside and naringenin. The diminished expression of PAL, 4CL, and HCT decreased the formation of cyanidin-3-O-(6”-O-malonyl-2”-O-glucuronyl) glucoside, leading to the emergence of emerald green leaves. Moreover, the lowered expression of TGA and WRKY46 indirectly regulated 4CL activity, serving as another important factor in maintaining the emerald green hue in leaves N1, N2, and N3.ConclusionThese findings establish a foundation for elucidating the molecular regulatory mechanisms governing anthocyanin biosynthesis in quinoa leaves, and also provide some theoretical basis for the development of leisure and sightseeing agriculture.

Assessment of Soil Quality of Smallholder Agroecosystems in the Semiarid Region of Northeastern Brazil

The assessment of soil quality is crucial for the sustainable development of agriculture in semiarid regions. Due to their sensitivity to management practices, soil chemical and physical quality indicators are used for investigating soil quality. This study aimed to assess the soil quality of smallholder agroecosystems from the Brazilian semiarid region. Soil physical and chemical attributes were screened using principal component analysis (PCA) and integrated into a weighted additive soil quality index (SQI). Soil quality was obtained using linear and non-linear scoring methods, a total data set (TDS), and a minimum data set (MDS). The soil quality of the agroecosystems was designated as being of moderate grade. The MDS for soil quality assessment includes cation exchange capacity, C stock, exchangeable sodium percentage, flocculation degree, pH, electrical conductivity, available P, and K+ from twenty-five indicators of the TDS. This MDS mainly reflects the input of manure and crop residues associated with moderate weathering of easily weatherable minerals given the semiarid conditions. The SQI obtained can be used to synthesize the information of the TDS and is a valuable tool to indicate the soil quality of agroecosystems; thereby, it can be used with indicators of sustainable management for application at a regional scale.

Physiology and development of grafted dwarf cashew seedlings under different fertilization doses and irrigated with saline water

Salinity is one of the primary challenges faced by irrigated agriculture in semi-arid regions. This study aimed to investigate the effects of fertilization on the development of cashew seedlings irrigated with water of varying salinity levels. The research was conducted in a protected environment at Embrapa Agroindústria Tropical, Fortaleza, using grafted seedlings of the BRS 189 clone on CCP 06 rootstock. The treatments resulted from the combination of three levels of NPK fertilization (control - without fertilization, 50% less than conventional nutrition, and 100% of conventional nutrition used by the crop), which was incorporated into the substrate before sowing CCP 06, with four salinity levels (ECa of 0.8, 4.0, 7.0, and 10.0 dS m-1) of the irrigation water for the seedlings. Gas exchange, assimilate accumulation, growth, and nutrient content in the leaves, stems, and roots of the seedlings were evaluated 90 days after grafting. The data were subjected to analysis of variance, and when a significant effect was observed, the Tukey test was performed, while quantitative data were subjected to regression analysis. Overall, fertilization levels did not influence seedling growth. Fertilization did not interfere with photosynthate production, which performed better when the seedlings were subjected to a salinity of 7.0 dS m-1. The application of NPK to the substrate resulted in higher levels of nitrogen in the leaves, while phosphorus content decreased, and foliar potassium was not influenced by fertilization.

Revitalizing Key Conditions and Integrated Watershed Management to Mitigate Land Degradation and Sustain Water Availability for Agriculture in Semi-Arid Regions: A Case Study of Ethiopia

Land, the source of 97% of global food, remains threatened by progressive soil erosion-induced land degradation, such as, in the semi-arid regions. To address this problem, soil and water conservation interventions have been implemented in watersheds across Ethiopia. Despite witnessing successful and positive impacts in some watersheds, the broader promotion of watershed-based interventions faces obstacles. Soil and water deteriorations persist in many of the watersheds in Ethiopia, leading to water shortages and related challenges in sustaining agriculture. The objectives of this research are thus to i) identify the main challenges and constraints hindering the promotion of watershed-based interventions in Ethiopia, and ii) identify key conditions for revitalizing the Integrated Watershed Management (IWSM) approach to mitigate soil erosion-induced land degradation, rehabilitate and sustainably manage watershed resources. A systematic review of over 60 published articles, extracted from the internet database using various search engines such as Google Scholar, ScienceDirect, Academia.edu, and ResearchGate, was conducted. Additionally, valuable comments from 65 peer-reviewers worldwide were collected through the Qeios platform during a posting period for more than two months, and these comments were utilized to update the first preprint version of this article. Based on the review, identified challenges and limitations include poor institutional support, lack of participation, inadequate planning of soil and water conservation (SWC) technologies, absence of research and development linkages, and insufficient capacity building. To address these challenges and limitations, recommendations for revitalizing the integrated watershed management (IWSM) approach and key conditions are discussed. The identified key conditions for revitalizing watershed-based interventions in Ethiopia include: i) ensuring institutional support and community participation, ii) strengthening the watershed-based intervention, and iii) establishing a watershed-based platform for scientific tools, research-based innovation, and capacity building to sustain water availability for agriculture in Ethiopia, serving as an experience for other semi-arid regions.

Co-Cultivation and Matching of Early- and Late-Maturing Pearl Millet Varieties to Sowing Windows Can Enhance Climate-Change Adaptation in Semi-Arid Sub-Saharan Agroecosystems

In semi-arid regions, climate change has affected crop growing season length and sowing time, potentially causing low yield of the rainfed staple crop pearl millet (Pennisetum glaucum L.) and food insecurity among smallholder farmers. In this study, we used 1994–2023 rainfall data from Namibia’s semi-arid North-Central Region (NCR), receiving November–April summer rainfall, to analyze rainfall patterns and trends and their implications on the growing season to propose climate adaptation options for the region. The results revealed high annual and monthly rainfall variabilities, with nonsignificant negative trends for November–February rainfalls, implying a shortening growing season. Furthermore, we determined the effects of sowing date on grain yields of the early-maturing Okashana-2 and local landrace Kantana pearl millet varieties and the optimal sowing window for the region, using data from a two-year split-plot field experiment conducted at the University of Namibia—Ogongo Campus, NCR, during the rainy season. Cubic polynomial regression models were applied to grain-yield data sets to predict grain production for any sowing date between January and March. Both varieties produced the highest grain yields under January sowings, with Kantana exhibiting a higher yield potential than Okashana-2. Kantana, sown by 14 January, had a yield advantage of up to 36% over Okashana-2, but its yield gradually reduced with delays in sowing. Okashana-2 exhibited higher yield stability across January sowings, surpassing Kantana’s yields by up to 9.4% following the 14 January sowing. We determined the pearl millet optimal sowing window for the NCR to be from 1–7 and 1–21 January for Kantana and Okashana-2, respectively. These results suggest that co-cultivation of early and late pearl millet varieties and growing early-maturing varieties under delayed seasons could stabilize grain production in northern Namibia and enhance farmers’ climate adaptation. Policymakers for semi-arid agricultural regions could utilize this information to adjust local seed systems and extension strategies.

Soil quality assessment and constraint diagnosis of salinized farmland in the Yellow River irrigation area in northwestern China

The widespread occurrence of saline soils in arid and semi-arid agricultural regions necessitates the development of simple and practical methods for assessing soil quality in salinized farmland where soil constraints vary depending on farmland type. Herein six different salinized farmland types were selected from the Hetao Plain irrigation area in the upper reaches of the Yellow River plain (Ningxia, China) to assess the soil quality and diagnose potential soil constraints. An integrated quality index (IQI) was calculated using four combinations of nonlinear scoring (SNL) and linear scoring (SL) functions with the total data set (TDS) and minimum data set (MDS) methods. Sixteen indicators of soil physical and chemical properties were included in the TDS, seven of which were selected as MDS indicators, including sand content, total nitrogen, electrical conductivity, and cation exchange capacity. IQI values derived from the MDS method mirrored the results from the TDS method. The soil quality assessed by the four different methods showed consistent spatial patterns across the six farmland types, despite differences in details. In most cases, the highest IQI values were obtained based on TDS-SL, whereas MDS-SL yielded the lowest IQI values. Compared with the results of MDS-SL, IQI values derived from MDS-SNL were closer to those from TDS-SNL. When assessed using the MDS-SNL method, medium- and low-quality soils accounted for >98.0% of Calcic Solonchaks and Takyr Solonetzs. Fluvic Solonchaks had the largest proportion of medium-quality soils (86.5%). The major soil constraint was soil texture for Calcic Solonchaks and Haplic Solonchaks, nutrient limitation for Takyr Solonetzs, saline stress for Haplic Solonetzs, and co-existing soil texture and nutrient limitation for Fluvic Solonchaks and Stagnic Solonchaks. This study unravels multiple soil constraints across various salinized farmland types with medium-to-low soil quality in a major commercial grain base in northwestern China. MDS-SNL-based IQI can be useful for large-scale soil quality assessment in salinized farmland in the Yellow River irrigation area.

Assessment of the effects of integrated rotation-tillage management on wheat productivity in the Loess Plateau region

The long-term use of conventional management practices coupled with the overapplication of synthetic fertilizers by smallholder family farms to meet food demand has negatively impacted the environment of farmland. Therefore, improved agronomic management practices are needed to enhance crop productivity. A 3-year (2016–2019) experiment was conducted to evaluate the effects of integrated rotation-tillage management [maize/soybean-wheat (MW/SW); chisel plow tillage (CPT), zero tillage (ZT), and plow tillage (PT)] on the farmland environment and wheat productivity in the Loess Plateau of China. The results indicated that SW and conservation tillage (CPT and ZT) increased soil nutrient levels and decreased soil pH and C/N values compared with conventional management practices (MW and PT); meanwhile, conservation tillage substantially increased soil moisture (SM, 3.56–16.06 %) compared with PT. Compared with MW and PT, SW and CPT increased aboveground biomass (0.26–4.45 % and 0.73–2.15 %, respectively) and nitrogen content (1.24–2.30 % and 0.26–2.73 %, respectively) during wheat development. Coincidentally, SW increased wheat actual yield (AY, 2.98 %) and maintained wheat theoretical yield (TY) and harvest index (HI) compared with MW; CPT increased wheat grain yield (AY, 6.72 %; TY, 3.28 %) and HI (2.26 %) compared with PT, while ZT caused significantly opposite results. CPT increased nitrogen fertilizer productivity (NfP, 3.28 %), nitrogen uptake efficiency (NupE, 1.19 %), and nitrogen use efficiency (NUE, 1.67 %) compared with PT regardless of crop rotations, while ZT significantly decreased NfP (9.69 %) and NupE (16.99 %) and increased NUE (8.18 %). Nevertheless, crop rotation did not substantially affect wheat nitrogen efficiency. Further correlation and partial least squares path modeling analysis revealed that elevated SM and nitrogen levels due to improved management practices had the potential to improve wheat productivity by regulating wheat growth characteristics. Overall, integrated SW-CPT management was more positive for improving farmland environment and enhancing wheat productivity in the Loess Plateau, which is suitable as a conservation strategy to adjust the cropping structure of smallholder family farms and promote sustainable agricultural development in arid and semiarid agricultural regions.

Seasonal Variations in Yield and Biochemical Composition of the Mediterranean Saltbush (Atriplex halimus L.) Under Saline Agriculture in Semi-Arid Regions

Seasonal Variations in Yield and Biochemical Composition of the Mediterranean Saltbush (Atriplex halimus L.) Under Saline Agriculture in Semi-Arid Regions

Fertilization strategies for abating N pollution at the scale of a highly vulnerable and diverse semi-arid agricultural region (Murcia, Spain)

Overuse of N fertilizers in crops has induced the disruption of the N cycle, triggering the release of reactive N (Nr) to the environment. Several EU policies have been developed to address this challenge, establishing targets to reduce agricultural Nr losses. Their achievement could be materialized through the introduction of fertilizing innovations such as incorporating fertilizer into soils, using urease inhibitors, or by adjusting N inputs to crop needs that could impact in both yields and environment. The Murcia region (southeastern Spain) was selected as a paradigmatic case study, since overfertilization has induced severe environmental problems in the region in the last decade, to assess the impact of a set of 8 N fertilizing alternatives on crop yields and environmental Nr losses. Some of these practices imply the reduction of N entering in crops. We followed an integrated approach analyzing the evolution of the region in the long-term (1860–2018) and considering nested spatial- (from grid to region) and systems scales (from crops to the full agro-food system). We hypothesized that, even despite reduction of N inputs, suitable solutions for the abatement of Nr can be identified without compromising crop yields. The most effective option to reduce Nr losses was removing synthetic N fertilizers, leading to 75% reductions in N surpluses mainly due to a reduction of 64% of N inputs, but with associated yield penalties (31%–35%). The most feasible alternative was the removal of urea, resulting in 19% reductions of N inputs, 15%–21% declines in N surplus, and negligible yield losses. While these measures are applied at the field scale, their potential to produce a valuable change can only be assessed at regional scale. Because of this, a spatial analysis was performed showing that largest Nr losses occurred in irrigated horticultural crops. The policy implications of the results are discussed.

Seed pre-sowing treatments and essential trace elements application effects on wheat performance

Current study was conducted to evaluate the effects of different seed priming and foliar spray of micronutrients on bread wheat performance in semi-arid region in Northwest of Iran. Pre-sowing treatments were S1: no pre-sowing treatment (intact seeds), S2: hydro-priming, S3: bio-priming (seed inoculation with plant promoting rhizobacteria consortium: Azotobacter chroococcum + Azospirillum lipoferum), S4: micronutrient seed priming and foliar feeding include, check (0): distilled water spray, Fe: foliar spray of iron, Zn: foliar spray of zinc. All seed priming treatments significantly increased plant height, tiller number, canopy width, total biomass, spike mass, seed number per spike and seed yield compared to intact seeds. A brief comparison of the effect of seed priming and fertilizer treatments showed that the effects of priming treatments on improving growth and seed yield was more obvious than fertilizer treatments. The greatest increase in seed yield and yield components was recorded for plants grown from bio-fortified seeds by essential trace elements. However, comparison of fertilizer treatments showed that growth parameters were significantly affected by Zn application. From the present study, it may be concluded that combined seed priming through pre-sowing hydration, soaking in micronutrients and microbial inoculation is useful to enhance wheat production and agricultural sustainability for smallholder farmers in semi-arid region.

Growth, Solute Accumulation, and Ion Distribution in Sweet Sorghum under Salt and Drought Stresses in a Brazilian Potiguar Semiarid Area

Agriculture in semiarid regions commonly face problems because of salt and availability of irrigation water. Considering this, studies on cultures resistant to salt and water stresses involving sweet sorghum are required. Therefore, the aim was to evaluate the growth and other mechanisms of tolerance to salinity and water deficit in BRS 506 sweet sorghum. The experimental design was conducted in Upanema-RN, Brazil, in randomized blocks, where the isolated and interactive effect of 3 salinity levels, expressed as the electrical conductivity of irrigation water (1.5, 3.8, and 6.0 dS m−1), and 3 irrigation depths (55, 83, and 110% of crop evapotranspiration) were evaluated. During the cycle, sorghum adapted to the salinity and deficit irrigation depth, since stem height reduced only −5.5% with increasing salinity and −11.95% with decreasing irrigation depth, and aerial dry mass was affected by interaction only at the end of the cycle. Proline, total amino acids, and total soluble sugars were not differenced by stresses. Additionally, around 68.71% of total Na+ was at roots at the end of the cycle. In summary, sorghum BRS 506 was more tolerant to salt than water stress and used Na+ compartmentalization in root cells as the main tolerance mechanism.

Seed priming with essential oils for sustainable wheat agriculture in semi-arid region.

Drought is one of the major constraints to global crop production. A number of sustainable systems have focused on the development of environmentally friendly innovative biotechnological interventions to prevent yield losses. The use of essential oils as a seed priming agent can make an important contribution as a natural stimulant in increasing drought stress tolerance. This study focuses on the effects of seeds coated with different doses (D0 (0%), D1 (0.01%), D2 (0.05%), D3 (0.10%) and D4 (0.25%)) of sage, rosemary and lavender essential oils on wheat germination, seedling establishment and yield parameters. Turkey's local wheat genotype Köse was used as plant material. The impact of the seed priming on germination rate, coleoptile length, shoot length, root length, shoot fresh and dry weight, root fresh and dry weight, relative water content (RWC), proline, and chlorophyll contents was assessed in laboratory experiments. In addition, the effect of essential oil types on yield parameters and agronomic components (plant height, spike height, number of grains per spike, grain yield per spike, grain yield per unit area, thousand-grain weight) was evaluated in a field experiment during the 2019-2020 crop seasons in a semi-arid climate. According to laboratory results, the highest germination rate among all treatment doses was determined in the D2 treatment (rosemary 93.30%, sage 94.00% and lavender 92.50%), while the lowest germination rates for all essential oil types were determined in the D4 treatment (rosemary 41.70%, sage 40.90% and lavender 40.90%). Increasing treatment doses showed a similar suppressive effect on the other parameters. In the field experiment, the highest grain yield (256.52 kg/da) and thousand-grain weight (43.30 g) were determined in the rosemary treatment. However, the priming treatment has an insignificant on the number of grains per spike and the spike length. The light of these results, the effects of essential oil types and doses on yield parameters were discussed. The findings highlight the importance of using essential oils in seed priming methods for sustainable agricultural practices.

Effects of Tillage Systems on the Physical Properties of Soils in a Semi-Arid Region of Morocco

Climate change, drought, erosion, water contamination resources, desertification, and loss of soil quality represent major environmental risks worldwide. Facing these risks is the most important issue for sustainable development. Conventional tillage (CT) practices seem to expose the soils of semi-arid regions, which are initially fragile, to degradation that is accentuated by the overuse of the environment. The benefits of conservation agriculture (CA) could mitigate the degradation of natural resources, particularly soils. The adaptation and transfer of the no-till (NT) system with mulch open new perspectives for the development of agriculture in semi-arid regions. The main objective of this study is to assess the impact of conservation agriculture, especially no-till (NT) system, on the physical properties of soil (structural stability (SS), bulk density (BD), gravimetric water content (θg), and soil organic matter (SOM)) compared to conventional tillage (CT). The main changes associated with the transition from a CT system to an NT system were evaluated at the experimental site, Merchouch (M13), which is typified by vertisol soil, and at the Ain Sbit (AS7) site, which is characterized by isohumic soil. Under a no-till system, most of the physical properties of the soil were improved in both sites, with a clear difference in the M13 site. Structural stability under NT showed a significant increase in both sites (fast wetting (FW), slow wetting (SW), and wet stirring (WS) improved by 88, 43, and 83% at the M13 site, respectively, against, 16, 23, and 7%, respectively, at the AS7 site). On the other hand, the SOM increased from 2.0 to 2.6% (an improvement of 28%) at AS7 and from 1.2% to 1.9% (an improvement of 52%) at M13. This research demonstrated that conservation agriculture, especially NT, improves the soil physical quality in both medium and long terms, confirming its suitability for the climatic and edaphic constraints of semi-arid areas in Morocco as well as in other parts of the world.

Effects of postharvest deficit irrigation on sweet cherry (Prunus avium) in five Okanagan Valley, Canada, orchards: II. Phenology, cold hardiness, fruit yield, and quality

Irrigated agriculture in semi-arid regions is expected to increase in the future, which puts greater demands on scarce water resources. Sustainable irrigation strategies in semi-arid regions will support agricultural resilience to climatic change. The response of “Sweetheart”/Mazzard sweet cherry trees ( Prunus avium L.) to postharvest deficit irrigation (PDI), as a water conservation method, was studied over three seasons (2019–2022) in the semi-arid Okanagan Valley of British Columbia, at five commercial orchards. The following irrigation treatments were applied; ( i) a control of full irrigation, irrigated according to conventional growers’ practice at each orchard, ( ii) PDI-30: 27%–33% reduction in irrigation volume, after harvest (67%–73% of control), and ( iii) PDI-50: 47%–52% reduction in irrigation volume, after harvest (48–53% of control). Spring phenology (the timing of flower bud development, from side green to full bloom), flower bud moisture content and cold hardiness, and fruit yield and quality (before and after cold storage and shelf-life conditions) were assessed to determine if PDI altered fruit development over the subsequent growing season. Neither PDI-30 nor PDI-50 caused changes in the timing of flower bud phenology, cold hardiness or moisture content relative to the control. PDI treatments also had no effect on fruit yield or fruit quality at harvest or after storage and shelf-life conditions. These results suggest PDI could be used to reduce irrigation water use in semi-arid regions, like the Okanagan Valley, without affecting sweet cherry production or fruit quality.