ABSTRACT Excessive application of nitrogen (N) fertilizer has acidified soils to pH levels below the optimum, posing a threat to tea plant cultivation. Organic livestock manure rich in alkaline substances can counteract the H+ produced by soil nitrification of N fertilizer. However, how ameliorating acidification using livestock manure affects nitrification and greenhouse gas nitrous oxide (N2O) emissions in tea-planted soils remains unclear. Here, by adding four types of manure (cow, sheep, chicken, and pig) at rates of 0, 100, and 200 mg N kg−1 into a tea-planted soil, we showed that all manure additions alleviated soil acidification and increased net N mineralization and nitrification significantly, with the increases becoming more pronounced with increasing rate. While soil cumulative N2O emissions were enhanced significantly by sheep, chicken, and pig manure and reduced significantly by cow manure at the high rate, with opposite trends at the low rate. Net nitrification and cumulative N2O emissions were significantly and negatively correlated with carbon (C)/N of added manure at both rates and at the high rate alone, respectively. Our findings highlight the importance of selecting the appropriate livestock manure (i.e. high C/N) to alleviate soil acidification while minimizing nitrification and N2O emissions.

ABSTRACT Wheat yield in Pakistan is constrained by improper seed rates and weed interference. A two-year field trial (2020–2021) was conducted to determine the optimal seed rate and critical weed competition period for wheat. Treatments included three seed rates (37, 74, and 111 kg ha−1) with weed competition and weed-free periods up to 45, 60, and 75 days after sowing (DAS), along with full-season competition. The treatments were arranged in an RCBD in three replications. Results showed that a seed rate of 111 kg ha−1 with a weed-free period up to 75 DAS significantly reduced weed cover, density, and dry weight. It also enhanced plant height, productive tillers, grains per spike, 1000-grain weight, grain yield, biological yield, crop vigor, growth rate, leaf area index, test weight, and grain protein content of wheat. Weed-free up to 45 DAS resulted in better performance than the same duration of weed competition, showing that early-season weed control is important. The study confirms that the critical period for weed management may begin before 45 DAS and extend to around 75 DAS and recommends a seed rate of 111 kg ha−1 with at least 60 DAS weed-free period to maximize growth, yield, and quality of wheat.

ABSTRACT Weed infestation limits soybean yield and profitability, necessitating effective and selective herbicides for sustainable production. Soybean (Glycine max L. Merr.) is a key legume with high protein and oil content, playing an important role in global agriculture. In Pakistan, only non-GMO soybean is cultivated with limited herbicide options. This study, conducted over two growing seasons (2022–2023) at the Agronomic Research Farm, University of Agriculture, Faisalabad, evaluated 16 treatments, including six pre-emergence and eight post-emergence herbicides, along with a control and weedy check. Results highlighted the importance of weed management in preventing substantial yield losses. Among pre-emergence herbicides, S-metolachlor + pendimethalin performed best, with a 91.21–95.65% weed control, a high herbicide efficiency (27.54–32.48%), and minimal crop injury (10% susceptibility index). Among post-emergence herbicides, fluazifop-p-butyl proved most effective, ensuring high weed control efficiency (89.73–92.36%), minimal crop damage (10% susceptibility index), and increased grain yield. In contrast, herbicides like S-metolachlor + atrazine + Mesotrione, Topramezone, Mesosulfuron-methyl + iodosulfuron-methyl sodium, and Mesotrione + atrazine caused complete plant mortality. This study identified S-metolachlor + pendimethalin (pre-emergence) and fluazifop-p-butyl (post-emergence) as the most effective herbicides for soybean, ensuring optimal weed control, minimal crop injury, and higher yield.

ABSTRACT Cattle manure (CM) and biochar are rich sources of plant nutrients, and serve as soil conditioners to improve soil properties, but their low solubility may slow nutrient release. The experiment aimed to evaluate the impact of CM, biochar and K fertilizer on maize growth and yield, and on soil properties. The experiment was conducted for two consecutive years. CM and biochar application along with K fertilizer significantly increased the growth and yield parameters. The highest grain yield of 3455 kg ha−1 was recorded in plots receiving CM along with K at 120 kg ha−1. Moreover, CM and biochar application with K fertilizers increased distribution of the K content, which was higher for CM than biochar. The highest K content of soil was 221 kg ha−1 when K was applied at 120 kg ha−1 with CM. Also, extractable P, total N and organic matter were significantly increased during both years. Application of CM or biochar along with K fertilizers also significantly reduced the soil sodium adsorption ratio, electrical conductivity and bulk density. Hence, K fertilization combined with organic amendments like CM or biochar may enhance maize growth and yield, compared to organic amendment alone.

ABSTRACT Soil fungi tolerate drought better than bacteria, making them vital for climate-related soil studies. This study examined the responses of the two most abundant fungal phyla in topsoil, Ascomycota and Basidiomycota, to extreme temperature and moisture conditions under controlled conditions. Two soils from the same geographic region but with contrasting land-use histories (ploughed vs. unploughed) were analysed. Initial fungal and bacterial biomass quantifications in terms of rRNA gene copy number showed that fungi were more stable than bacterial biomass under the imposed abiotic stress, highlighting their key role in soil microbial resilience. Further analysis using phylum-specific primers and digital PCR revealed that the Ascomycota phylum experienced stable growth under simulated extreme fluctuations in soil moisture. In contrast, the biomass of Basidiomycota doubled under water-stressed conditions compared to optimal field conditions. However, under flooding and abnormally hot conditions, it halved. Ascomycota, which is largely composed of spore-dispersed fungi that prevail in ploughed soils, contributes to microbial stability during extreme events. Basidiomycota, on the other hand, has an underestimated capacity to sustain microbial biomass through prolonged drought. The findings highlight the crucial role of forest and conservation-oriented land uses where Basidiomycetes thrive, in enhancing soil microbial stability as drought progressively increases.

ABSTRACT Waterlogging is a major abiotic stress limiting sesame (Sesamum indicum L.) production in low-lying areas of Bangladesh, primarily due to excessive rainfall and poor drainage. To identify tolerant genotypes and understand their physiological responses, a two-year field study (February 2023–June 2024) was conducted at the Stress Research Site, Department of Agronomy, Gazipur Agricultural University, Bangladesh. In the first experiment, 89 local and exotic sesame genotypes were evaluated under control and 3-d waterlogging imposed at 14 d after sowing (DAS). Based on the total dry matter accumulation, five tolerant genotypes (BD-7005, BD-6961, BD-6998, BD-7004, and BD-7001) were selected. In the second experiment, these genotypes were further tested under 3-d waterlogging at the flowering stage (35 DAS) and under well-watered conditions, following a randomized complete block design (RCBD) with three replications. Waterlogging stress significantly reduced stomatal conductance, transpiration, chlorophyll, and photosynthesis, while increasing intercellular CO2 concentration and malondialdehyde content. In contrast, proline and total sugar contents increased, indicating osmotic adjustment. Among the genotypes, BD-7005 exhibited superior tolerance by maintaining higher leaf water content, chlorophyll, photosynthetic efficiency, membrane stability, and seed yield. These findings suggest BD-7005 as a promising candidate for breeding waterlogging-tolerant sesame suitable for flood-prone regions of Bangladesh.

ABSTRACT The semi-arid grasslands of northwestern China are characterized by fragile ecosystems, limited water resources, and significant degradation. This study investigates the effects of different land-use practices, such as fencing, grazing, and tourism, on soil preferential flow in the semi-arid grasslands of central Inner Mongolia. The preferential flow process was observed using the dye tracer method and quantitatively analyzed via image processing to determine morphological features. Results indicated that preferential flow was observed in all areas, but the extent varied significantly: fenced areas exhibited the most pronounced preferential flow at both 25 mm and 50 mm infiltration volumes. Preferential flow mainly occurred in the top 30 cm, with a decreasing ratio of dyed area at greater depths. At 25 mm infiltration, the preferential flow ratio exceeded 50% in fenced areas. Increasing the volume to 50 mm resulted in peak values for infiltration depth and stained area ratio, although the proportion of preferential flow decreased. Key factors influencing preferential flow included soil bulk density, texture, and root nutrient characteristics. This study provides essential insights for effective grassland management and water resource conservation, contributing to the governance of semi-arid ecosystems by prioritizing fencing to improve soil health.

ABSTRACT Accurate prediction of nitrogen (N) mineralization following the termination of grass-clover is essential for improving N efficiency in agricultural systems. In this study, short-term N mineralization after fall termination of grass-clover, followed by a winter rye cover crop, was evaluated over winter in comparison to intact grass-clover (control). Soil samples of a Plaggic Anthrosol were collected after fall termination and in the subsequent spring in two consecutive years (2021–2023) from a field trial with grass-clover in North-West Germany. Nitrogen mineralization was assessed through laboratory incubation experiments and modeling using rate coefficients and pedotransfer functions from the literature. Laboratory results indicated a high short-term N mineralization potential immediately after grass-clover termination in fall and in the following spring. While the potential net N release in the fall-terminated treatment decreased from fall to spring, the control treatment increased. Modeled N mineralization in fall aligned well with the fall-terminated treatment but overestimated the N release for the control. By applying the model under field conditions from fall to spring, grass-clover termination resulted in the mineralization of 61.62 kg N ha−1. This prediction of mineralizable N could be further used to assess the risk of environmentally significant N losses and to optimize N fertilization.

ABSTRACT Limited varieties along with planting position are among the major factors that limit cassava production in Ethiopia. Therefore, a field experiment was conducted in the Mela and Bodi sub-districts of Gena Bosa district in Dawro Zone during 2017 cropping seasons, to determine the response of cassava varieties to different planting positions. The treatments consisted of four varieties (Local, Variety, Kello and Awassa-04 varieties) and three planting positions (inclined at an angle of about 45°, 90° and 180°). The experiment was laid out as a randomized complete block design (RCBD) and replicated three times per treatment. Data were collected on phenology, growth, yield components and yield. The data were subjected to analysis of variance. The results indicated that interaction effects of variety and planting position significantly affected all parameters. Kello variety planted slant planting position both at Mela and Bodi sub-districts significantly improved the phenology, growth, root morphology, yield components, and root yield of cassava. The highest mean net benefit (210,544 ETB ha−1) with an acceptable marginal rate of return of 12,493% was obtained from Kello variety planted slant planting position. Thus, planting Kello variety in slant planting position is suggested for maximizing agronomic and economic returns of cassava farmers.

ABSTRACT Co-inoculation with beneficial microbiology has become important in different hydroponic crops. Cannabis sativa L. is a plant rich in products of secondary metabolism. Phenolic compounds and flavonoids act as anti-inflammatory, anti-aging, and anti-cancer agents due to their antioxidant properties. However, the interactions between microbiota and their effect on the synthesis of antioxidant compounds during the vegetative stage have not been studied in depth. Therefore, this research focus to evaluate the impact of Pseudomonas fluorescens and Trichoderma spp. on the dynamics of the nutrient environment, physiological development and the production of antioxidant compounds. Five treatments were evaluated: without inoculation; 3.33 × 104; 6.67 × 104; 1.00 × 105; 1.33 × 105 CFU L−1 of P. fluorescens and Trichoderma spp. in a divided plot design under controlled conditions. The results showed that 6.67 × 104 CFU L−1 stimulated the best development in terms of height (51.24 cm), stem diameter (9.83 mm) and aboveground biomass, as well as increased production of antioxidant compounds, specifically quercetin (353.64 mg) and gallic acid (51.25 mg) in the plant. Finally, high densities of microorganisms in the rhizosphere inhibited vegetative growth. Co-inoculation in the hydroponic system is a biotechnological alternative for the production of antioxidant metabolites.