Waqar Ahmad

Chilli pepper is a major cash crop in many countries, making a substantial contribution to export markets and national Gross Domestic Product (GDP). The production and quality of chilli peppers is significantly affected by biotic and abiotic stresses, particularly diseases caused by fungal, bacterial and viral pathogens. This review focuses on the major diseases such as anthracnose, root rot, powdery mildew and Fusarium wilt that led to substantial crop losses every year. Both traditional and contemporary non-indigenous strategies for inducing disease resistance have been discussed. The article maps key practices including the adoption of proper cultural practices, use of algal extracts and raising of disease-resistant varieties, application of biological and chemical control methods aimed at enhancing disease resistance in chilli. Relevant case studies are included to assess and support the effectiveness of agricultural practices that have proven effective in reducing crop losses and improving yield quality. The economic implications of improved disease resistance for tropical regions have also been discussed. Key recommendations are provided for policymakers, farmers and exporters and the need for technical and financial support as well as modern processing facilities to meet international market demands is emphasized. Further studies are required especially from the tropical areas where chilli consumption and cultivation are increasing. Proactive measures such as sustainable nursery management, integrated approaches and cluster-based frameworks are recommended to enhance early intervention and risk mitigation to protect crop and achieve sustainability. These insights offer a foundation for developing targeted strategies to improve crop resilience and productivity in regions facing similar challenges.

Despite the proven impact of biochar (BC) on crop yield, little is known about its effect on cereal grain quality. We explored the effect of acacia pruning-derived biochar and nitrogen (N) applications on the mineral profile of maize grains in a field study. Biochar was applied at the rates of 5, 10, 15, and 20 t ha⁻¹ and N at 100, 150, and 200 kg ha⁻¹ along with the control (BC or N not applied) in a split-plot arrangement using a randomized complete block design. At crop maturity, the grains were analyzed for K, P, Ca, Mg, Zn, Fe, and Cu content. The results showed that BC application at the rate of 10 t ha⁻¹ along with N at 200 kg ha⁻¹ resulted in the highest concentrations of K, P, Ca, and Mg in grains. The Fe content was the maximum at the N application rate of 200 kg ha⁻¹ while Zn and Cu had the highest concentration at 150 kg N ha⁻¹ with no BC. It was concluded that the integrated use of BC and N could be a valuable strategy to improve the nutritional quality of maize grains. The enrichment of BC with micronutrients is recommended to achieve the desired concentration of micronutrients in maize grains to help cure malnutrition. However, further investigation is warranted to validate the impact of BC made of different feedstocks on soils of contrasting mineralogy as organo-mineral interactions might mask the true potential of BC.

Editorial: Global Food and Nutrition Security Under Changing Climates

The aim of the present study was to investigate the effect of withering timings (i.e. 0, 21, 22, 23 and 24h) on the moisture, total free amino acids, ash, essential and toxic mineral element contents of tea (Camellia sinensis L.) leaves during black tea manufacturing. Moisture, ash, Na, P, Mg, Cu, Zn, Mn, Al, Ni and Pb contents were significantly (P0.05) results were noted for total free amino acids, K, Fe and Cd contents. The highest moisture content (76.4%) was examined in fresh leaves that progressively decreased to 63.8% in 24h withering. Total free amino acid contents gradually increased up to 23h and then decreased. Ash, P, Cu, Zn and Mn contents showed an increasing trend with withering time. Conversely, significantly lowered amounts of Na (162.5mg/kg) and Mg (803mg/kg) were recorded in tea leaves after 24h withering. Among the toxic elements, Al, Ni and Pb contents were progressively increased over withering time. It was concluded that tea is a potential source of essential chemical constituents and during processing proper care should be taken to produce high quality black tea

Lime is a common amendment to overcome soil acidity in agricultural production systems. However, plant root effects on lime and soil carbon (C) dynamics in acidic soils under varied temperature remain largely unknown. We monitored root effects of soybean on the fate of lime applied to an acidic soil at 20 and 30°C in growth chambers. Soil respired CO ₂ was continuously trapped in columns without and with plants until the final stage of vegetative growth. Lime‐derived CO ₂ was separated from total respired CO ₂ based on δ ¹³ C measurements in CO ₂ . Leaching was induced at early and late vegetative growth stages, and the leachates were analysed for dissolved organic (DOC) and inorganic C (DIC) concentrations. Soil respiration significantly increased with lime addition at both temperatures ( p < 0.001). The presence of soybean doubled the recovery of lime‐derived CO ₂ ‐C at 20°C at the early growth stage; however, by the end of the experiment, the contribution of lime‐derived CO ₂ ‐C to soil respiration was negligible in all treatments, indicating that the contribution of lime to soil respiration was shortlived. In contrast, DIC and DOC concentrations in leachates remained elevated with liming and were greater in the presence of soybean. We observed no main temperature effects and no interactive effects of temperature and soybean presence on lime‐derived CO ₂ ‐C, DIC and DOC. These results highlight the role of plant‐modulated processes in CO ₂ release and C leaching from lime in acidic soils, whereas an increase in temperature may be less important. Temperature and plant roots alter the rate of key processes controlling C dynamics in a limed acidic soil. Lime‐derived CO ₂ ‐C, DIC and DOC increased more in the presence of plants than with increased temperature. Root effects are more important than temperature for inorganic and organic carbon dynamics in limed acidic soils.

We investigated the role of ethylene diamine tetra-acetic acid (EDTA) and somaclonal manipulation on improving lead (Pb) phytostabilization in mat rush (Juncus effusus L.). Seedlings were raised from seeds and callus to study variations in Pb uptake and tolerance. The seedlings were treated with 0.5 and 1.0mM Pb as alone, and each with 2.5 and 5.0mM of EDTA. Plants grown from both sources accumulated relatively larger Pb contents in their root tissues that were further enhanced by EDTA supplementation in the hydroponics medium. The tendency of storing higher Pb contents in roots compared to shoots in J. effusus was also evident from lower translocation factor (TF) value that facilitated the plants to avoid from Pb-induced shoot injury. Callus grown plants were more responsive to EDTA amendment showing improved growth, Pb uptake and chlorophyll contents under Pb stress. Both kinds of J. effusus plants tolerated Pb toxicity by modifying antioxidative enzyme activities. Enrichment of Pb-treated media with EDTA further elevated enzymic activities of plant roots contributing to defy Pb-induced oxidative burst. Thus, plant improvement through somaclonal manipulation in J. effusus along with EDTA enrichment could be an appropriate technique for phytostabilization of Pb-contaminated environments

Background and aims Use of zinc (Zn) fertilisers may be cost-effective in increasing crop yields and in alleviating dietary Zn deficiency. However, Zn fertilisers are underutilised in many countries despite the widespread occurrence of Zn-deficient soils. Here, increased Zn fertiliser-use scenarios were simulated for wheat production in Punjab and Sindh Provinces, Pakistan. Inputs and outputs were valued in terms of both potential yield gains as well as health gains in the population. Methods The current dietary Zn deficiency risk of 23.9 % in Pakistan was based on food supply and wheat grain surveys. “Disability-adjusted life years (DALYs) lost” are a common metric of disease burden; an estimated 245,000 DALYs y⁻¹ are lost in Punjab and Sindh due to Zn deficiency. Baseline Zn fertiliser-use of 7.3 kt y⁻¹ ZnSO₄.H2O was obtained from published and industry sources. The wheat area currently receiving Zn fertilisers, and grain yield responses of 8 and 14 % in Punjab and Sindh, respectively, were based on a recent survey of >2500 farmers. Increased grain Zn concentrations under Zn fertilisation were estimated from literature data and converted to improved Zn intake in humans and ultimately a reduction in DALYs lost. Results Application of Zn fertilisers to the area currently under wheat production in Punjab and Sindh, at current soil: foliar usage ratios, could increase dietary Zn supply from ~12.6 to 14.6 mg capita ⁻¹ d⁻¹, and almost halve the prevalence of Zn deficiency, assuming no other changes to food consumption. Gross wheat yield could increase by 2.0 and 0.6 Mt. grain y⁻¹ in Punjab and Sindh, respectively, representing an additional return of US$ >800 M and an annual increased grain supply of 19 kg capita ⁻¹. Conclusions There are potential market- and subsidy-based incentives to increase Zn fertiliser-use in Pakistan. Benefit-Cost Ratios (BCRs) for yield alone are 13.3 and 17.5 for Punjab and Sindh, respectively. If each DALY is monetised at one to three fold Gross National Income per capita on purchasing power parity (GNI_PPP), full adoption of Zn fertiliser for wheat provides an additional annual return of 405–1216 M International Dollars (I$) in Punjab alone, at a cost per DALY saved of I$ 461–619.