Biochar Production and Characteristics, Its Impacts on Soil Health, Crop Production, and Yield Enhancement: A Review.

Rapid urban expansion and a booming population are placing immense pressure on our agricultural systems, leading to detrimental impacts on soil fertility and overall health. Due to the extensive use of agrochemicals in agriculture, the necessity to meet the expanding demand for food has also resulted in unsustainable farming practices. Around the world, biochar, a multipurpose carbonaceous material, is being used to concurrently solve issues with enhancing soil fertility, plant growth, and development under both normal and stressful circumstances. It improves water retention, fosters nutrient absorption, and promotes microbial activity, creating a fertile environment that supports sustainable and resilient agriculture. Additionally, biochar acts as a carbon sink, contributing to long-term carbon sequestration and mitigating climate change impacts. The major benefit of biochar is that it helps the adsorption process with its highly porous structures and different functional groups. Understanding the elements involved in biochar formation that determine its characteristics and adsorptive capacity is necessary to assure the viability of biochar in terms of plant productivity and soil health, particularly biological activity in soil. This paper focuses on the development, composition, and effects of biochar on soil fertility and health, and crop productivity.

Moringa Leaf Extract Mitigates the Adverse Impacts of Drought and Improves the Yield and Grain Quality of Rice through Enhanced Physiological, Biochemical, and Antioxidant Activities.

Agriculture, around the globe, is facing great challenges including the need to increase the production of nutrient-dense food and to withstand climate change's impact on water and soil conservation. Among these challenges, drought stress is considered the most overwhelming danger for the agriculture sector. Organic plant growth ingredients are frequently used to enhance the growth and production of field crops cultivated in normal and unfavorable conditions. The present study was designed to explore whether leaves extracted from various landraces of Moringa could play a defensive role against drought stress in rice. Seedlings were grown under three water conditions, i.e., normal conditions (control; 100% field capacity), moderate (75%), and severe drought (50%). Leaf extracts obtained from four Moringa landraces were used as foliar spray at the tillering, panicle initiation, and grain filling stages of cultivating rice plants. The levels of water stress negatively influenced photosynthetic pigment synthesis, gas exchange traits, antioxidant activities, and yield and grain quality parameters. Leaf extracts, at the rate of 3%, from all the landraces significantly enhanced the biochemical, physiological, and yield-related attributes of rice plants under normal and unfavorable growth conditions. Particularly, leaf extract from the Faisalabad landrace was the most effective biostimulant to increase photosynthetic (8.2%) and transpiration (13.3%) rates, stomatal conductance (8.3%), chlorophyll a (15.9%) and b (9.7%) contents, and carotenoids (10.4%) as compared to water spray. The maximum photosynthesis rate was observed at 14.27 µmol CO2 m-2 s-1 via application of leaf extract from the Faisalabad landrace followed by the DG Khan (13.92 µmol CO2 m-2 s-1) and Multan (13.9 µmol CO2 m-2 s-1) landraces, respectively. Improved grain yield (25.4%) and grain quality (an increase of 10.1% in amylose with a decrease of 2.8% in amylopectin) in rice plants along with enzymatic activities such as catalase (21.2%), superoxide dismutase (38.6%), and ascorbate peroxidase (24.3%) were observed at the peak after application of leaf extract from the Faisalabad landrace. The maximum grain yield of 53.59 g per plant was recorded when using Faisalabad landrace leaf extract and the minimum (40 g) using water spray. It is concluded from the findings of the current experiment that leaf extract from the Faisalabad landrace possesses higher biostimulant potential than other landraces and can be applied to mitigate the adverse impacts of drought stress with higher productivity and improved grain quality of rice.

Molecular markers-based DNA fingerprinting coupled with morphological diversity analysis for prediction of heterotic grouping in sunflower (Helianthus annuus L.).

Cultivated sunflower holds a very narrow genetic base and the efficient utilization of available genetic diversity is very important for a successful breeding program. In the present study, 109 sunflower genotypes were assessed for diversity paneling through a combined approach of morphological and molecular markers analysis. Morphological parameters including days to flower initiation, days to flower completion, plant height, stem curvature, number of leaves per plant, leaf area, head diameter, hundred seed weight, and seed yield per plant were studied. Simple sequence repeats (40 DNA markers) were deployed for diversity profiling. Data were analyzed by both univariate and multivariate statistics. SD and coefficient of variation confirm the presence of significant amounts of genetic variation for all the morphological parameters. Cluster Analysis and Principal Component Analysis further confirm the presence of distinct grouping patterns in the studied material. Cluster analysis of both morphological and molecular analysis revealed that restorer lines tend to group separately from A, B, and open-pollinated lines. Further grouping, at the sub-cluster level, revealed six distinct sub-clusters in each of the two major clusters. In total, 12 genotypes, 6 CMS lines (CMS-HAP-12, CMS-HAP-54, CMS-HAP-56, CMS-HAP-99, CMS-HAP-111, and CMS-HAP-112) and 6 restorer lines (RHP-38, RHP-41, RHP-53, RHP-68, RHP-69, and RHP-71) could be used as potential parents for hybrid development. As genotypes of similar genetic backgrounds tend to group closer, it is deduced that one genotype with the highest seed yield per plant could be used for further hybrid breeding programs in sunflowers.

Impact of different levels of zinc and nitrogen on growth, productivity, and quality of aromatic rice cultivated under various irrigation regimes in two districts of Pakistan.

Rice is a staple food for more than 50% of the global population and it is one of the most valuable cereal crops. To fulfill the dietary requirement of the ever-growing world population, an increase in per-unit production of rice is direly required. In Pakistan, it stands as the 2nd in consumption after wheat, which is a staple food. A huge gap is observed between yield potential and actual yield of the aromatic rice cultivars at a farmer-field level. The significant limitations responsible for this gap are shortage of irrigation water, inappropriate application of fertilizers, less plant population, deficiency of micronutrients, and improper and poor plant protection measures. A field study was planned to assess the yield response and quality attributes of aromatic rice to three levels of zinc (Zn) and nitrogen (N) under three irrigation regimes (8-, 12-, and 16-acre inches) in the Sheikhupura and Sargodha districts of Pakistan. Irrigation treatments significantly influenced the growth, yield, and quality attributes; however, maximum improvement was observed by the application of irrigation at 12-acre inches. Among the Zn treatments, application of Zn at 10 kg ha-1 was observed to be more responsive to improving the growth and quality parameters of aromatic rice crops. In the case of N treatments, application of N at 140 kg ha-1 produced the maximum total tillers, as well as productive tillers per hill, spikelets per panicle, leaf area index, leaf area duration, crop growth rate, total dry matter, harvest index, kernel length, kernel width, and 1,000-kernel weight. Application of N at 140 kg ha-1 not only improved the growth attributes but also increased the net assimilation rate, photosynthetically active radiation, and radiation use efficiency, with respect to total dry matter and kernel yield. The maximum percentage of normal kernels and minimum percentage of opaque, abortive, and chalky kernels were also recorded by application of N at 140 kg ha-1. The outcomes of current experiments depicted that application of irrigational water, zinc, and nitrogen at 12-acre inches, 10, and 140 kg ha-1, respectively, are responsible to achieve maximum resource utilization efficiency, along with increased yield and quality of rice.

Preliminary Study on Growth and Yield Potential of Ten Elite Lines of Quinoa (Chenopodium quinoa) Cultivated under Varying Sowing Dates.

Optimization of agronomic practices for cultivation of quinoa, a super food and climate resilient crop, is critical to obtain its maximum grain yield under the current scenario of climate change. In the present experimentation, we evaluated the appropriate sowing time of ten elite lines of quinoa, already screened from USDA germplasm. Seeds of each line were sown in the experimental area at Square No. 22, Block No. 5, Directorate of Farm, University of Agriculture, Faisalabad, Pakistan on 15 November, 30 November and 15 December during quinoa cultivation season of 2019-2020. Sowing time significantly affected the emergence percentage, days taken to anthesis, chlorophyll contents, sodium and potassium concentrations in leaf, plant height, stem diameter, number of leaves and leaf area, panicle length, grain yield and 1000-grain weight. Lines; PIA-922, PIA-924, PIA-928 and PIA-929 performed better under first sowing and produced higher grain yield as compared to other lines. Similarly, PIA-921, PIA-922, PIA-925 and PIA-932 produced maximum biomass and grain yield under second sowing date while in case of third sowing date, PIA-926, PIA-928, PIA-930 and PIA-931 were observed more responsive regarding growth and yield attributes. A diversified pattern of agronomic, growth and yield contributing attributes of quinoa lines was observed when cultivated under varying sowing dates. The collected data will be very informative for the breeders and agronomists during selection and variety development process in future.

Nitrogenous Fertilizer Coated With Zinc Improves the Productivity and Grain Quality of Rice Grown Under Anaerobic Conditions.

An ample quantity of water and sufficient nutrients are required for economical rice production to meet the challenges of ever-increasing food demand. Currently, slow-release nitrogenous fertilizers for efficient inputs utilization and maximum economic yield of field crops are in the limelight for researchers and farmers. In this study, we evaluated the comparative efficacy of conventional urea and coated urea (zinc and neem) on rice grown under aerobic and anaerobic regimes in greenhouse conditions. For the aerobic regime, field capacity was maintained at 80-100% to keep the soil aerated. On the other hand, for the anaerobic regime, pots were covered with a polythene sheet throughout the experimentation to create flooded conditions. All forms of urea, conventional and coated (zinc and neem), improved plant growth, gas exchange, yield, yield contributing parameters, and quality characteristics of rice crop. However, better performance in all attributes was found in the case of zinc-coated urea. Gas exchange attributes (photosynthetic rate, 30%, and stomatal conductance 24%), yield parameters like plant height (29%), tillers per plant (38%), spikelets per spike (31%), grains per panicle (42%), total biomass (53%), and grain yield (45%) were recorded to be maximum in rice plants treated with zinc-coated urea. The highest grain and straw nitrogen contents, grain protein contents, and grain water absorption ratio were also found in plants with zinc-coated urea applications. In irrigation practices, the anaerobic regime was found to be more responsive compared to the aerobic regime regarding rice growth, productivity, and quality traits. Thus, to enhance the productivity and quality of rice grown in anaerobic conditions, zinc-coated urea is best suited as it is more responsive when compared to other forms of urea.

Foliar application of mepiquat chloride and nitrogen improves yield and fiber quality traits of cotton (Gossypium hirsutum L.).

Cotton (Gossypium hirsutum L.) is one of the most important cash crops primarily grown for fiber. It is a perennial crop with indeterminate growth pattern. Nitrogen (N) is extremely important for vegetative growth as balanced N-nutrition improves photosynthesis, resulting in better vegetative growth. Excessive N-supply results in more vegetative growth, which increases the incidence of insect pest and diseases' infestation, pollute surface and ground water, delays maturity and produces low crop yield with poor quality. The use of plant growth regulators (PGRs) is an emerging option to control excessive vegetative growth. The PGRs help in improving plant architecture, boll retention, boll opening, yield and quality by altering growth and physiological processes such as photosynthesis, assimilate partitioning and nutrients dynamic inside the plant body. Mepiquat chloride (1,1-dimethylpiperidinum chloride) is globally used PGR for canopy development and control of excessive vegetative growth in cotton. This study investigated the effect of mepiquat chloride (MC) and N application on yield and yield components of transgenic cotton variety 'BT-FSH-326'. Two N rates (0, 198 kg ha-1) and five MC rates (0, 30,60, 90 and 120 g ha-1) were included in the study. Results revealed that MC and N application improved boll weight, number of bolls per plant, and seed cotton and lint yields. The highest seed cotton and lint yields (3595 kg ha-1 and 1701 kg ha-1, respectively) were observed under foliar application of 198 kg ha-1 N and 120 g ha-1 MC. Fiber length, fiber strength, micronaire and uniformity were significantly improved with foliar application of MC and N. In conclusion, foliar application of MC and N could be helpful in improving yield and fiber quality of cotton.

Application of natural and synthetic growth promoters improves the productivity and quality of quinoa crop through enhanced photosynthetic and antioxidant activities.

Modern agriculture is primarily concerned with enhanced productivity of field crops linked with maximum resources use efficiency to feed the increasing population of the world. Exogenous application of biostimulants is considered a sustainable and ecofriendly approach to improve the growth and productivity of agronomic and horticultural field crops. The present study was carried out to explore the comparative growth enhancing potential of plant biostimulants (moringa leaf extract at 3% and sorghum water extract at 3%) and synthetic growth promoters (ascorbic acid at 500 µM and hydrogen peroxide at 100 µM) on growth, productivity and quality of quinoa crop (cultivar UAF-Q7) because it has gained significant popularity among agricultural scientists and farmers throughout the world due to its high nutritional profile. A field experiment was carried out at the Research Area of Directorate of Farms, University of Agriculture, Faisalabad, Pakistan during quinoa cultivation season of 2016-2017 and repeated during next year (2017-2018). All the foliar treatments enhanced the physiological, biochemical, quality, growth and yield attributes of quinoa as compared to control group. However, maximum improvement was observed in chlorophyll a and b contents, photosynthesis and respiration rates, and water use efficiency by moringa leaf extract (MLE) application. MLE application was also found more responsive regarding the improvement in activities of peroxidase, catalase, superoxide dismutase, phenolics and glycine betaine as compared to other treatments. Mineral elements i.e. K, Ca and N in root as well as in shoot were found the highest in response to MLE application. Similarly, growth (plant fresh and dry biomass, plant length and grain yield) and grain quality parameters (protein, K and Ca) were also significantly enhanced. Application of MLE was found to be a viable approach to improve the growth and quality of produce as compared to synthetic compounds.

Impact of varying levels of soil salinity on emergence, growth and biochemical attributes of four Moringa oleifera landraces.

Salinity in soil and water is one of the environmental factors that severely hinder the crop growth and production particularly in arid and semi-arid regions. A pot experiment was conducted to investigate the impact of salinity levels (1.5 dS m-1, 3.5 dS m-1, 7.5 dS m-1 and 11.5 dS m-1) on emergence, growth and biochemical traits of moringa landraces under completely randomized design having three replications. Four landraces of Moringa oleifera (Faisalabad black seeded moringa [MFB], Patoki black seeded moringa [MPB], Faisalabad white seeded moringa [MFW] and Rahim Yar Khan black seeded moringa [MRB]) were selected for experimentation. All the salinity levels significantly affected the emergence parameters (time to emergence start, time to 50% emergence, mean emergence time, emergence index and final emergence percentage) of moringa landraces. However, 1.5 dS m-1 and 3.5 dS m-1 were found more favorable. Higher salinity levels (7.5 dS m-1 and 11.5 dS m-1) significantly minimized the root surface area, root projected area, root volume and root density as compared to 1.5 dS m-1, 3.5 dS m-1. Number of branches, leaves, leaflets and leaf length were also adversely affected by 7.5 dS m-1 and 11.5 dS m-1. Maximum seedling fresh and dry weights, and seedling length were recorded at 1.5 dS m-1 followed by 3.5 dS m-1. Chlorophyll a and b contents, carotenoids and membrane stability index were also observed highest at salinity level of 1.5 dS m-1. In case of moringa landraces, MRB performed better regarding emergence attributes, growth parameters, and biochemical analysis followed by MFW as compared to MFB and MPB. Moringa landraces i.e. MRB and MFW were found more tolerant to salinity stress as compared to MFB and MPB.

Foliar application of potassium and moringa leaf extract improves growth, physiology and productivity of kabuli chickpea grown under varying sowing regimes.

Chickpea (Cicer arietinum L.) is of prime importance because of vital source of protein as major food legume. Globally, it is cultivated on large area to meet dietary requirements of humans. Climatic extremes (erratic rainfall, extreme high and low temperature) are key restrains for its production. Optimum sowing time is considered as an important factor to address climatic variations and to attain maximum yield. Foliar application of potassium (K) has also been reported to increase resistance against abiotic stresses. Similarly, exogenous application of plant based growth substances (bio-stimulants) like moringa leaf extract (MLE) are extensively used to enhance productivity of field crops. Therefore, current study was planned to evaluate the impact of foliar applied K and MLE on growth, physiology and productivity of kabuli chickpea grown under varying sowing dates. There were two sowing dates (normal sown; November 15 and late sown; December 15, 2020). Experiment was comprised of treatments i.e. control, water spray, foliar application of K at 1%, foliar application of MLE at 3% and combined application of K and MLE. Foliar applied K and MLE significantly improved physiological, biochemical and yield attributes of kabuli chickpea cultivated under normal and late sown conditions. Increase in growth and yield attributes like plant height, number of nodules per plant, nodules dry weight, branches and pods per plant, 100- grain weight, biological and grain yield were recorded in case of combined foliar application of K and MLE in normal and late sown chickpea. Maximum improvement in gas exchange attributes (stomatal conductance and transpiration rate), chlorophyll contents, antioxidants (catalase, superoxide dismutase and ascorbate peroxidase) and osmolytes (proline) were recorded with combined application of K and MLE in both sowing dates. Thus, combined applied K and MLE can be used to enhance productivity of kabuli chickpea.

Application of Zinc and Iron-Based Fertilizers Improves the Growth Attributes, Productivity, and Grain Quality of Two Wheat (Triticum aestivum) Cultivars.

Field-based experiments were conducted during wheat cultivation seasons of 2017-2018 and 2018-2019 to minimize the impact of hidden hunger (micronutrient deficiencies) through agronomic biofortification of two wheat cultivars with zinc and iron. Two spring-planted bread wheat cultivars: Zincol-16 (Zn-efficient) and Anaj-17 (Zn-inefficient with high-yield potential) were treated with either zinc (10 kg/ha), iron (12 kg/ha), or their combination to study their effect on some growth attributes (plant height, tillers, and spike length, etc.,), productivity, and quality. No application of zinc and iron or their combinations served as the control. Maximum Zn and Fe contents of grains were improved by sole application of Zn and Fe, respectively. A higher concentration of Ca in grains was observed by the combined application of Zn and Fe. Starch contents were found maximum by sole application of Fe. Sole or combined application of Zn and Fe reduced wet gluten contents. Maximum proteins were recorded in Anaj-17 under control treatments. Zincol-16 produced maximum ionic concentration, starch contents, and wet gluten as compared to Anaj-17. Yield and growth attributes were also significantly (p < 0.05) improved by combined application as compared to the sole application of Zn or Fe. The combined application also produced the highest biological and grain yield with a maximum harvest index. Cultivar Anaj-17 was found more responsive regarding growth and yield attributes comparatively. The findings of the present study showed that the combined application of Zn and Fe produced good quality grains (more Zn, Fe, Ca, starch, and less gluten concentrations) with a maximum productivity of bread wheat cultivars.

Exogenous application of moringa leaf extract improves growth, biochemical attributes, and productivity of late-sown quinoa.

Quinoa (Chenopodium quinoa Willd.) has gained significant popularity among agricultural scientists and farmers throughout the world due to its high nutritive value. It is cultivated under a range of soil and climatic conditions; however, late sowing adversely affects its productivity and yield due to shorter growth period. Inorganic and organic phyto-stimulants are promising for improving growth, development, and yield of field crops under stressful environments. Field experiments were conducted during crop cultivation seasons of 2016-17 and 2017-18, to explore the role of inorganic (hydrogen peroxide and ascorbic acid) and organic [moringa leaf extract (MLE) and sorghum water extract (sorgaab)] phyto-stimulants in improving growth and productivity of quinoa (cultivar UAF-Q7). Hydrogen peroxide at 100 µM, ascorbic acid at 500 µM, MLE at 3% and sorgaab at 3% were exogenously applied at anthesis stage of quinoa cultivated under normal (November 21st and 19th during 2016 and 2017) and late-sown (December 26th and 25th during 2016 and 2017) conditions. Application of inorganic and organic phyto-stimulants significantly improved biochemical, physiological, growth and yield attributes of quinoa under late sown conditions. The highest improvement in these traits was recorded for MLE. Application of MLE resulted in higher chlorophyll a and b contents, stomatal conductance, and sub-stomatal concentration of CO2 under normal and late-sowing. The highest improvement in soluble phenolics, anthocyanins, free amino acids and proline, and mineral elements in roots, shoot and grains were observed for MLE application. Growth attributes, including plant height, plant fresh weight and panicle length were significantly improved with MLE application as compared to the rest of the treatments. The highest 1000-grain weight and grain yield per plant were noted for MLE application under normal and late-sowing. These findings depict that MLE has extensive crop growth promoting potential through improving physiological and biochemical activities. Hence, MLE can be applied to improve growth and productivity of quinoa under normal and late-sown conditions.

Moringa leaf extract improves biochemical attributes, yield and grain quality of rice (Oryza sativa L.) under drought stress.

Changing climate, food shortage, water scarcity and rapidly increasing population are some of the emerging challenges globally. Drought stress is the most devastating threat for agricultural productivity. Natural plant growth substances are intensively used to improve the productivity of crop plants grown under stressed and benign environments. The current study evaluated whether leaf extract of different moringa (Moringa oleifera L.) could play a role in improving drought-tolerance of rice (Oryza sativa L.). Rice plants were grown under three drought conditions, i.e., no, moderate and severe drought (100, 75 and 50% field capacity, respectively). Moringa leaf extract (MLE) obtained from four landraces (Multan, Faisalabad, D. G. Khan and exotic landrace from India) was applied during critical crop growth stages, i.e., tillering, panicle initiation and grain filling. Drought stress adversely affected the gas exchange attributes, photosynthetic pigments, antioxidant enzymes' activities, yield and quality parameters of rice. Application of MLE from all landraces significantly improved physiological, biochemical and yield parameters under stressed and normal environmental conditions. The highest improvement in gas exchange traits (photosynthetic rate, stomatal conductance and respiration rate), photosynthetic pigments (chlorophyll a, b and carotenoids) and enzymatic activities (superoxide dismutase, catalase) and oxidative marker (H2O2) was recorded with MLE obtained from Faisalabad landrace. The application of MLE of Faisalabad landrace also improved yield and grain quality of rice grown under drought stress as well as drought-free environment. Thus, MLE of Faisalabad can be successfully used to improve growth, productivity and grain quality of rice under drought stress.

Author Correction: Effect of Plant Density, Boron Nutrition and Growth Regulation on Seed Mass, Emergence and Offspring Growth Plasticity in Cotton.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Effect of Plant Density, Boron Nutrition and Growth Regulation on Seed Mass, Emergence and Offspring Growth Plasticity in Cotton.

Seed nutrients reserves have direct relationship with seed functional traits and influence offspring performance. Effects of plant density, foliage boron (B) nutrition and mepiquat chloride (MC) growth regulation on seed nutrients reserves, seed mass and production, and emergence and offspring growth traits of cotton were studied in two years field experiment. Seed nutrients reserves and seed mass were decreased at higher maternal plant density relative to lower plant density with concomitant decrease in emergence and offspring seedling growth. However, maternal foliage B nutrition and MC growth regulation enhanced seed nutrients reserves, seed mass, emergence and offspring seedling growth performance. There was a significant positive relationship between seed mass and seed nutrients reserves indicating that changes in nutrient availability/uptake in response to maternal ecological factors determine variation in seed functional traits. Nonetheless, seed mass was positively correlated with emergence percentage and negatively with emergence timing. Furthermore, variation in offspring seedling growth traits with seed mass indicated the significance of initial seed nutrients reserves for early seedling vigour and establishment. In conclusion, lower maternal plant density, B nutrition and MC growth regulation ensued in higher emergence and offspring seedling growth of cotton because of higher seed nutrient reserves and seed mass.