Soil Potassium Content Research Articles

Relationships between Soil Electrical Conductivity and Sentinel-2-Derived NDVI with pH and Content of Selected Nutrients

Site-specific crop management demands maps which present the content of the main macronutrients. Such maps are prepared based on optimized soil sampling within management zones, which should be quite homogenous according to nutrient content, especially the content of potassium and phosphorus. Delineation of management zones is very often conducted using soil apparent electrical conductivity (EC) or other variables related to soil condition, including satellite-derived vegetation indices. In this study conducted in North-Western Poland, relationships between soil electrical conductivity and the satellite-derived normalized difference vegetation index (NDVI) of various crops (wheat, barley, and rapeseed) with soil pH and content of P, K, and Mg were evaluated. Strong relationships were observed between NDVI of cereals with potassium content in soil. Correlation coefficients for wheat ranged from 0.37 to 0.60 for average potassium content for three years and from 0.05 to 0.63 for barley. Stronger relationships were observed for the years 2018 and 2019 when NDVI was based on Sentinel-2 data, while weaker for year 2017 when Landsat 8 NDVI was used. Relationships between EC and macronutrients content were similar to those observed with NDVI. Satellite-derived NDVI of cereals can be used as a variable for the delineation of within-field management zones. The same relationships were much weaker and not consistent for winter rapeseed.

Inoculation of Maize with 1-Aminocyclopropane-1-Carboxylic Acid Containing Pseudomonas fluorescens for Enhanced Available Nutrients in Soils of Maize (Zea mays L.)

A field and lab experiment entitled “Kinetics of 1-Aminocyclopropane-1-carboxylic -deaminase (ACCD) activity of Pseudomonas fluorescens, its population growth under different fermentation conditions and performance of the selected isolates on maize” was conducted at Laboratory of Microbes Research & Production Centre (MRPC) and the Research Farm, Department of Soil Science and Agricultural Chemistry, Jawaharlal Nehru Krishi Vishwa Vidyalaya, Jabalpur, Madhya Pradesh during 2018-19. The results revealed that the available nitrogen (N) content in soil at knee height, tasseling and silking stage, the treatment combination Temperature 28oC and pH 7.2 (T28+pH 7.2) isolates significantly increase the N content in soil with response of 21.5,17.3 and 14.4% over FUI (209, 196 and 166 kg N ha-1), respectively. Similarly, the isolates of T28+pH 7.2 significantly increase the available phosphorus (P) content at knee height, tasseling and silking stage in soil with response of 31.7, 23.2 and 26.4% over FUI (18.0,16.4 and 14.4 kg P ha-1). The isolates of T28+pH 7.2 significantly increase the available potassium (K) content in soil at knee height, tasseling and silking stage with response of 14.4, 10.1 and 10.4% over FUI (298, 278 and 264 kg K ha-1).

Potentials of straw return and potassium supply on maize (Zea mays L.) photosynthesis, dry matter accumulation and yield

Maize (Zea mays L.) is considered one of the most important grains in the world. Straw return has the effect of reducing soil bulk density and increasing soil porosity. Straw returning and potassium fertilizer can supplement soil potassium content. The improvement of soil structure and the optimization of soil nutrient levels provide a good environment for high yield and high efficiency of maize. Therefore, three field experiments were carried out over a three-year period (2018–2020) to study the effects of straw returning on photosynthesis, dry matter accumulation and yield of maize 'Xianyu 335' under two different fertilization methods and four potassium application levels. The results showed that straw returning and potassium application had significant effects on the above indicators. The above indicators were significantly improved by deep tillage straw returning compared with no tillage straw returning. Increasing potassium supply can promote the effect of straw returning. The photosynthesis, dry matter accumulation and yield parameters of maize treated with straw returning and deep tillage combined with 60 kg/hm2 potassium fertilizer (SFK60) reached the highest in the three harvest seasons. The corn planting profit of SFK45 treatment is the highest, which is $1868.92 per ha. Therefore, SFK45 is an effective way to ensure stable and high yield of corn and maximize farmers' income.

Integrated Nutrient Management for Rice Yield, Soil Fertility, and Carbon Sequestration.

Reliance on inorganic fertilizers with less or no use of organic fertilizers has impaired the productivity of soils worldwide. Therefore, the present study was conducted to quantify the effects of integrated nutrient management on rice yield, nutrient use efficiency, soil fertility, and carbon (C) sequestration in cultivated land. The experiment was designed with seven treatments comprising of a zero input control, recommended inorganic fertilizers (RD), poultry manure (PM) (5 t ha−1) + 50% RD, PM (2.5 t ha−1) + 75% RD, vermicompost (VC) (5 t ha−1) + 50% RD, VC (2.5 t ha−1) + 75% RD, and farmers’ practice (FP) with three replications that were laid out in a randomized complete block design. The highest grain yield (6.16–6.27 t ha−1) was attained when VC and PM were applied at the rate of 2.5 t ha−1 along with 75% RD. Uptake of nutrients and their subsequent use efficiencies appeared higher and satisfactory from the combined application of organic and inorganic fertilizers. The addition of organic fertilizer significantly influenced the organic carbon, total carbon, total nitrogen, ammonium nitrogen, nitrate nitrogen, soil pH, phosphorus, potassium, sulfur, calcium, and magnesium contents in post-harvest soil, which indicated enhancement of soil fertility. The maximum value of the organic carbon stock (18.70 t ha−1), total carbon stock (20.81 t ha−1), and organic carbon sequestration (1.75 t ha−1) was observed in poultry manure at the rate of 5 t ha−1 with 50% RD. The soil bulk density decreased slightly more than that of the control, which indicated the improvement of the physical properties of soil using organic manures. Therefore, regular nourishment of soil with organic and inorganic fertilizers might help rejuvenate the soils and ensure agricultural sustainability.

Nutrient management studies on vegetative growth performance of dragon fruits

An experiment entitled “Nutrient management studies on vegetative growth performance of dragon fruit plants” was carried out during the year2018-19 at Experimental Farm, Department of Fruit Science, Faculty of Horticulture, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola with objective to study the effect of N.P.K. levels on vegetative growth of Dragon fruit and to find out the suitable concentration of N.P.K. for better vegetative growth of Dragon fruit under Akola condition. The experiment was laid out in Randomized Block design with ten treatments viz., T1 (200:50 NP) g/plant, T2 (200:37.5 NP) g/plant, T3 (200:50 NK) g/plant, T4 (200:37.5 NK) g/plant, T5 (150:50 NP) g/plant, T6 (150:37.5 NP) g/plant, T7 (150:50 Nk) g/plant, T8 (150:37.5 NK) g/plant, T9 (200:50:50 NPK) g/plant, T10 (150:37.5:37.5 NPK) g/plant. All treatment were replicated three times. The results of present investigation indicated that, the maximum plant height, number of branches, main stem circumference, plant canopy north to south, plant canopy east to west, number of sprouting, new shoots height was recorded in treatment T9 (200:50:50 N:P:K g/plant). The available nitrogen, phosphorous, potassium content in soil were maximum under treatment T9 (200:50:50 N:P:K g/plant).

Near-Infrared Spectral Waveband Selection for Soil Potassium Content Based on Simulated Annealing

Near-Infrared Spectral Waveband Selection for Soil Potassium Content Based on Simulated Annealing

Study of Potassium and Sodium content of Mahad-Raigad Tertiary Soil by Flame Photometry

The present study is devoted to determine the content of K, Na, pH of soil samples collected from Mahad tehsil territory. Elements leached from the deposits of the fertilizers have been accumulated in soil, thus constituting to soil pollution index. Focusing this study was carried out to compare out the nutrient contents of barren soil and Rice field soil in Mahad tehsil tertiary, by Flame photometry analysis.

Potassium mobilization and plant growth promotion by soil bacteria isolated from different agroclimatic zones of Odisha, India

Potassium is essential for plant metabolism; improves immunity to stress and increase crop productivity. Soil contains insoluble form of potassium, which is unavailable for plant absorption. Potash mobilizing bacteria (KMB) solubilise complex potassium and make it available to plant. KMB with plant growth promoting (PGP) traits could enhance growth and crop productivity. Here we attempt to screen KMBs with PGP traits from different agroclimatic zones of Odisha and study dynamics of potassium in soil. Isolation of KMB and determination of PGP traits was performed with standard protocols. Pot culture experiment was aimed to study their effect on sunflower crop. Available soil potassium was quantified using inductively coupled plasma-optical emission spectrometry (ICP-OES). Thirty KMBs were isolated from different agro-climatic zones of Odisha, out of which 6 isolates exhibited maximum PGP traits. Moreover, after adding inoculums the available soil potassium decreased over 0 to 30 days as compared to control, with increase in shoot length. T7 (consortium) reported maximum (144 %) increase in shoot length. Available soil potassium content decreased with increase in time. A maximum decrease was reported in T7 (26.31 %), suggesting potassium accumulation by plant.

Potassium mobilization and plant growth promotion by soil bacteria isolated from different agroclimatic zones of Odisha, India

<p class="042abstractstekst"><span lang="EN-US">Potassium is essential for plant metabolism; improves immunity to stress and increase crop productivity. Soil contains insoluble form of potassium, which is unavailable for plant absorption. Potash mobilizing bacteria (KMB) solubilise complex potassium and make it available to plant. KMB with plant growth promoting (PGP) traits could enhance growth and crop productivity. Here we attempt to screen KMBs with PGP traits from different agroclimatic zones of Odisha and study dynamics of potassium in soil. Isolation of KMB and determination of PGP traits was performed with standard protocols. Pot culture experiment was aimed to study their effect on sunflower crop. Available soil potassium was quantified using inductively coupled plasma-optical emission spectrometry (ICP-OES). Thirty KMBs were isolated from different agro-climatic zones of Odisha, out of which 6 isolates exhibited maximum PGP traits. Moreover, after adding inoculums the available soil potassium decreased over 0 to 30 days as compared to control, with increase in shoot length. T7 (consortium) reported maximum (144 %) increase in shoot length. Available soil potassium content decreased with increase in time. A maximum decrease was reported in T7 (26.31 %), suggesting potassium accumulation by plant.</span></p>

The Effect of Efficacy Local Isolates of Paenibacillus Bacteria on Available Soil Phosphorus and Growth of Cultivars Wheat (Triticum Aestivum L.)

A field experiment was carried out to study the effect of bio-inoculation with three local isolates of P. polymyxa and three Varieties of wheat on the growth and yield of the wheat plant (Triticum aestivum L). In the second agricultural research station affiliated to the College of Agriculture - University of Al-Muthanna, a field experiment was conducted in Al-Muthanna Governorate for the year 2020 in silty clay Loam soil texture. The experiment was designed in a randomized complete block method (RCBD) and with three replications. The experiment included two factors, where the first factor represents the local isolates of four levels, symbolized by P0-P1-P2-P3, and the second factor represents the three wheat varieties, Buhouth class 22, Iraq class, and Ibaa 99, which symbolized C1-C2-C3 respectively. The results showed the following: First: The P3 bio-pollination treatment achieved a significant increase in soil phosphorus, potassium, and nitrogen in the available part at the flowering stage, as the highest average was recorded for them (11.39 mg kg −1 soil - 1.4300%-1.4,000%), and the P2 treatment was superior for both soil potassium and plant height. And the dry weight, the highest average for them was recorded (157.8 mg kg −1 - 92.6 cm - 10.61 g plant −1). Second: As for the cultivars, they differed in most of the characteristics of the study. The Iraq cultivar excelled in soil phosphorous concentration with an average of (11.06 mg kg −1 soil), while Buhouth cultivar 22 was superior in soil potassium with an average of (158.02) mg kg −1 soil. Ibaa 99 had been recorded concentration nitrogen and potassium in plants with averages of (1.4208,1.3474%). Third: When the isolates overlapped with the cultivars, a discrepancy was observed. It gave Samawa isolate with Bohouth class 22 by recording the highest average in soil potassium concentration and plant height amounting to (166.7 mg kg −1 soil, 99.8 cm) respectively, while Al-Khidr isolate with Ibaa 99 cultivar in nitrogen and potassium concentration plant, where it reached (1.4567-1.4400)%, while the isolate without addition outperformed with the cultivar Iba 99 for dry weight, as it reached its highest average (11.40 gm plant −1). The isolate of vegetables also outperformed Iraq cultivar for phosphorous concentration in soil, as it recorded the highest average of (12.30) mg kg −1 soil.

Earthworm activity optimized the rhizosphere bacterial community structure and further alleviated the yield loss in continuous cropping lily (Lilium lancifolium Thunb.)

The soil microbial community plays a vital role in the biogeochemical cycles of bioelements and maintaining healthy soil conditions in agricultural ecosystems. However, how the soil microbial community responds to mitigation measures for continuous cropping obstacles remains largely unknown. Here we examined the impact of quicklime (QL), chemical fungicide (CF), inoculation with earthworm (IE), and a biocontrol agent (BA) on the soil microbial community structure, and the effects toward alleviating crop yield decline in lily. High-throughput sequencing of the 16S rRNA gene from the lily rhizosphere after 3 years of continuous cropping was performed using the Illumina MiSeq platform. The results showed that Proteobacteria, Acidobacteria, Bacteroidetes, Actinobacteria, Chloroflexi and Gemmatimonadetes were the dominant bacterial phyla, with a total relative abundance of 86.15–91.59%. On the other hand, Betaproteobacteriales, Rhizobiales, Myxococcales, Gemmatimonadales, Xanthomonadales, and Micropepsales were the dominant orders with a relative abundance of 28.23–37.89%. The hydrogen ion concentration (pH) and available phosphorus (AP) were the key factors affecting the structure and diversity of the bacterial community. The yield of continuous cropping lily with using similar treatments decreased yearly for the leaf blight, but that of IE was significantly (p < 0.05) higher than with the other treatments in the same year, which were 17.9%, 18.54%, and 15.69% higher than that of blank control (CK) over 3 years. In addition, IE significantly (p < 0.05) increased organic matter (OM), available nitrogen (AN), AP, and available potassium (AK) content in the lily rhizosphere soil, optimized the structure and diversity of the rhizosphere bacterial community, and increased the abundance of several beneficial bacterial taxa, including Rhizobiales, Myxococcales, Streptomycetales and Pseudomonadales. Therefore, enriching the number of earthworms in fields could effectively optimize the bacterial community structure of the lily rhizosphere soil, promote the circulation and release in soil nutrients and consequently alleviate the loss of continuous cropping lily yield.

The Role of Cover Crop Types and Residue Incorporation in Improving Soil Chemical Properties

Soil chemical properties can be improved by incorporating crop residues in soil and letting it decompose. This study explored the use of incorporating residues of cover crops for improvements in soil chemical properties including soil organic matter (SOM), soil pH, and the selected soil macro- and micronutrients in greenhouse and field trials. Factors of interest included (i) cover crops and their combinations and (ii) methods of crop termination and incorporation in soil (disc, mow + disc, glyphosate, roller crimper). The greenhouse trial showed up to a 20% higher amount of SOM accumulated in soils incorporated with crop residues. Buckwheat (3.12%) and phacelia (3.12%) produced significantly different and larger SOM than that of the control treatment that received no crop residues (p ≤ 0.05). The soil pH of the brown mustard treatment was also significantly affected by the experimental treatments (p ≤ 0.05). The incorporation of crop residues did not affect soil phosphorous (P) or potassium (K) concentrations, except for brown mustard, with significantly higher values of P and K than the control treatment. Calcium (Ca) was significantly higher in the soil of phacelia + pea treatment (p ≤ 0.05). Buckwheat + pea produced a higher concentration of Ca (1028 mg/kg) followed by buckwheat alone (1006 mg/kg). Analysis of variance (ANOVA) calculated on the results of the field trial showed that the mix treatment that had a mixture of four cover crops significantly increased the SOM content. Buckwheat produced the highest (2.95%) SOM, then brown mustard and timothy. This study concludes that, irrespective of the tillage incorporation methods, the residues from cover crops are a potential source of improvement in soil health, and this practice may promote sustainable agriculture in conditions similar to those in this study.

Eco-Geographical, Morphological and Molecular Characterization of a Collection of the Perennial Endemic Species Medicago tunetana (Murb.) A.W. Hill (Fabaceae) from Tunisia.

In order to characterize and conserve the endemic pastoral species Medicago tunetana, many prospecting missions were carried out in mountainous regions of the Tunisian ridge. Twenty-seven eco-geographical and morphological traits were studied for six M. tunetana accessions and followed by molecular analysis using seven Simple Sequence Repeat (SSR). Only five markers were polymorphic and reproductible in the six M. tunetana populations. A total of 54 alleles were observed with an average of 10.8 bands/primer/genotype. Mean Polymorphism Information Content (PIC), Nei gene diversity (h) Shannon’s information index (I) indicated the high level of polymorphism. The generated dendrogram with hierarchical UPGMA cluster analysis grouped accessions into two main groups with various degree of subclustring. All the studied accessions shared 57% of genetic similarity. Analysis of variance showed high significant difference between morphological traits among M. tunetana populations where MT3 from Kesra showed different morphological patterns regarding leaf, pod and seeds traits. Canonical correspondence analysis (CCA) showed two principal groups of M. tunetana populations based on potassium, total and active lime contents in soil. Our results suggest that SSR markers developed in M. truncatula could be a valuable tool to detect polymorphism in M. tunetana. Furthermore, the studied morphological markers showed a large genetic diversity among M. tunetana populations. This approach may be applicable for the analysis of intra specific variability in M. tunetana accessions. Our study could help in the implementation of an effective and integrated conservation programs of perennial endemic Medicago.

The main driving factors and responses to increase in soil available potassium in the Yangtze River basin over the past 30 years

AbstractIntensive crop rotation is one of the main causes of the continued depletion in soil potassium (K) content in the Yangtze River basin (YRB). However, recent studies have shown that soil K content is increasing in the YRB. Therefore, in this study, experimental and statistical data were collected to evaluate the soil K changes caused by K fertilizer application and straw return across the YRB. The results showed that soil available K increased, on average, by 21.7% across the YRB as a result of balanced K fertilization and an increasing proportion of straw return. From 1990 to 2019, K fertilizer input has increased from 10.1% to 24.1%, respectively. Meanwhile, from 2003 to 2011, the proportion of straw return increased by 32.8%. Considering these changes, we evaluated the effect of K fertilizer application and straw return on the soil K status. Overall, crop yield and soil available K increased by 9.9%, 7.3%, 16.3%, and 42.5%, 23.8%, and 66.4%, respectively, with K fertilization, straw return, and the concurrent use of both practices. Further, a synergistic increase in indigenous K input and soil available K alleviated the soil K negative balance and reduced the soil K fixation rate. In general, balanced K fertilization and an increasing proportion of straw return are the most vital measures for realizing the sustainable development of soil K across the YRB. The results of this research will provide useful information for sustainable K management and incentive policymaking.

Nutrient uptake, soil nutrient status and water use efficiency as influenced by drip fertigation in broccoli (Brassica oleracea var. italica)

Nutrient uptake by plant and nutrient status of soil after harvesting of crop varies markedly under fertigation and soil fertilization. A two year experiment was conducted at Vegetable Research Centre of G.B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India during the rabi seasons of 2016–2017 and 2017–2018 to study the effect of drip fertigation with levels and scheduling on nutrient uptake, soil nutrient status and water use efficiency in broccoli. The experiment was laid out in two factorial randomized block design with one additional treatment consisting of five fertigation levels and three fertigation scheduling along with control (soil application of RDF with flooding) replicated thrice. Increasing the fertigation levels favors in increasing the nitrogen, phosphorus and potassium uptake irrespective of the crop growth stage. At harvest, N, P and K uptake by broccoli under fertigation increased by 10.47, 17.39, 12.21% and 18.08, 15.88, 9.96% compared to the soil fertilization in the first and second year, respectively. Fertigation treatment increased the available phosphorus by 11.73 kg compared to soil fertilization. Available potassium content in soil after harvesting of crop depleted when compared to initial value. The consumptive water used for both the years varies between 150 mm and 195 mm under different fertigation treatments as compared to 300–325 mm under traditional method of irrigation. Fertigation treatments registered significantly higher WUE of 78.31 kg ha−1 mm−1 and it was higher by 95.48% over the conventional method of irrigation (40.06 kg ha−1 mm−1).

Spatial Distribution of The Elements and Assessment of The Status of Macro Elements in The Soils of Some Agricultural Districts within Al-Ramadi

This experiment was conducted to find a fertility case study to evaluate NPK elements in Ramadi city boundary. The experiment was carried out in Al-Bouabid, Al-Hamidiyah, Al-Tal`a, Al-Bu`asaf, Tawi, Tal Mashaid, Zwaijir and Zankoura in Anbar Governorate, the land usesed were planted with wheat, Alfalfa, citrus and palm trees for the 2019-2020 season. the samples taken to objective fertility analyzes for depths of (0-30) cm and (30-60) cm, where the results of the spatial distribution of NPK levels in the soils of the study areas showed that The spatial distribution of nitrogen and depth (0-30) cm showed total nitrogen content ranged between (0.441-1.439%). As for phosphorus, its content in the study areas ranged between (0.203-9.79) mg. Kg-1 and the level form Low by 100%, while the potassium content of soils in the studied areas was between (24.2-224) mg. kg-1, and the level was low about 82.13%, while the medium variety constituted 17.86% of the study areas. The results of the spatial distribution of nitrogen and depth (30-60) cm total nitrogen content ranged between (0.37-1.78) % and the person of the levels high and very high in the study areas, while the phosphorus content was between (0.215-17.3) mg. The two levels are Low and Medium, while the soil’s potassium content was between (26-234) mg. Kg -1 and it was within two levels, namely Low and medium.

Relationships of irrigation water and soil physical and chemical characteristics with yield, chemical composition and antimicrobial activity of Damask rose essential oil.

Damask rose (Rosa damascena Mill.) is an aromatic medicinal plant rich in bioactive compounds with high value in the food, pharmaceutical and cosmetic industries. Knowledge of the factors affecting the quantitative and qualitative properties of the compounds in its essential oil (EO) and the bioactivity of this EO is important in optimizing Damask rose cultivation and production. This research studied, for the first time, the effects of irrigation water and soil chemical and physical characteristics on the EO yield of this important commercial species and on it chemical composition and antimicrobial activity. The results showed the significant effect of crop cultivation site on yield, chemical composition and inhibition zone diameter (IZD) at the 1% significance level. The highest EO yield (~0.0266%), which belonged to the Noushabad site (EON), resulted from the increased soil electrical conductivity (EC) and the higher sand, gypsum and lime contents and irrigation water salinity. Analysis of the chemical composition of the EOs showed that their main compounds at all three crop sites were citronellol, nonadecane, heneicosane and geraniol. The EO obtained from the Yazdel site (EOY) had the highest contents of citronellol and geraniol (~29.05% and ~6.85%) that were directly correlated with soil potassium and phosphorus contents and inversely correlated with soil acidity and EC and its lime, nitrogen, and organic carbon contents. Antimicrobial assays indicated that the EO extracted from the Sefidshahr site (EOS), which had the largest inhibition zone diameter (~14.67 mm) for Aspergillus brasiliensis (IZD~14.67 mm) and the lowest MIC (~31.25 μg/mL) for Staphylococcus aureus and Pseudomonas aeruginosa, exhibited efficacy similar to that of rifampin, probably due to the dominance of the alkanes in it. The EOY and EOS also exhibited the strongest inhibitory and lethal activity against Candida albicans (MIC and MBC <15.63 μg/mL for EOY and MIC and MBC = 62.5 μg/mL for EOS), which were six and four times stronger than those of nystatin, respectively. Therefore, the selected EOs can act as a potentially promising strategy for fighting microbial strains.

Seed Priming and Coating by Nano-Scale Zinc Oxide Particles Improved Vegetative Growth, Yield and Quality of Fodder Maize (Zea mays)

Nano-fertilizers of essential plant nutrients, including micronutrients, have the potential to improve nutrient use efficiency and productivity of field crops in deficient soils. The present study reports the comparative influence of zinc oxide nanoparticles (ZnONPs) and bulk Zn salt (ZnSO4) on the growth, yield, and quality of fodder maize (Zea mays) (var. J-1006) cultivated under field conditions in the year 2019. Three levels (0, 20, and 40 mg L−1) of Zn fertilizers were used for seed priming and coating in triplicate following the randomized complete block design model. An increase in vegetative and yield parameters (number of plants, plant height, stover yield, plant biomass), acid detergent fiber (ADF%), and hemicellulose contents and shoot zinc (Zn) content on treatment of seeds with ZnONPs (20 mg L−1) concentration as compared to bulk ZnSO4 and control treatments was observed. The application of ZnONPs (40 mg L−1) significantly enhanced the total chlorophyll content, available soil nitrogen and phosphorus, neutral detergent fiber (NDF%), and cellulose contents and improved the total soil microbial counts and soil enzyme activities (dehydrogenase, acid and alkaline phosphatase enzyme activities), whereas a significant increase in available soil potassium and zinc contents was recorded under ZnONPs (20 mg L−1) treatments. These findings suggest an encouraging effect on the growth and yield attributing characteristics of fodder maize after ZnONPs seed coating at low concentration. Furthermore, ZnONPs seed coating can also be considered an effective tool for the delivery of Zn micronutrient to fodder maize crop.

Low soil moisture predisposes field-grown chickpea plants to dry root rot disease: evidence from simulation modeling and correlation analysis

Rhizoctonia bataticola causes dry root rot (DRR), a devastating disease in chickpea (Cicer arietinum). DRR incidence increases under water deficit stress and high temperature. However, the roles of other edaphic and environmental factors remain unclear. Here, we performed an artificial neural network (ANN)-based prediction of DRR incidence considering DRR incidence data from previous reports and weather factors. ANN-based prediction using the backpropagation algorithm showed that the combination of total rainfall from November to January of the chickpea-growing season and average maximum temperature of the months October and November is crucial in determining DRR occurrence in chickpea fields. The prediction accuracy of DRR incidence was 84.6% with the validation dataset. Field trials at seven different locations in India with combination of low soil moisture and pathogen stress treatments confirmed the impact of low soil moisture on DRR incidence under different agroclimatic zones and helped in determining the correlation of soil factors with DRR incidence. Soil phosphorus, potassium, organic carbon, and clay content were positively correlated with DRR incidence, while soil silt content was negatively correlated. Our results establish the role of edaphic and other weather factors in chickpea DRR disease incidence. Our ANN-based model will allow the location-specific prediction of DRR incidence, enabling efficient decision-making in chickpea cultivation to minimize yield loss.

Conservation agriculture-related practices contribute to maize (Zea mays L.) yield and soil improvement in Central Malawi

Conservation agriculture-related practices (CARP) improve soil fertility, maize yield, and profitability. A study was conducted to generate evidence on the benefits of CARP in the long-term (nine years) in Salima District, Central Malawi. The objectives of the study were 1) to compare the maize yields between farmer practice and CARP interventions in the long-term, 2) to compare soil fertility changes between farmer practice and CARP interventions in the long-term, and 3) to verify the intercropping efficiency of maize with groundnut using the land equivalent ratio (LER) and land equivalent coefficient (LEC). A guiding hypothesis was that the application of CARP improves soil condition and maize yield. Farmer practice (FP) and three CARP [Pit planting + mulching (PPM), Intercropping + mulching (INM), and Mulching (MC)] treatments were tested in the study. INM was also tested for intercropping efficiency. Maize yields in CARP (3.98–4.43 Mg ha−1) were significantly higher (p < 0.018) than in FP (1.84 Mg ha−1). Soil pH, soil organic carbon, soil organic matter, nitrogen, and bulk density were acceptable for the Malawian soil in CARP compared to FP, suggesting that CARP improved soil fertility properties. There was no significant difference in soil potassium concentration across the treatments (p < 0.0642). The land equivalent ratio for maize and groundnut intercropping in INM was 1.77, indicating beneficial intercropping efficiency. The benefit-cost ratios (BCR) for PPM, INM, and MC were 1.55, 1.90, and 2.26, respectively, indicating that CARP interventions were more profitable than FP (BCR = 0.15). It is concluded that CARP interventions contribute to increased crop yield, income, and soil fertility restoration in the agricultural land. The selection of a CARP intervention should depend on the farmer's main intention, either to maximize yield, soil fertility, income, or a combination.