Soil Application Of Humic Acid Research Articles

Effect of Soil and Foliar Application of Humic Acid on Nutrient Uptake, Grain and Straw Yield of Black Gram (Vigna mungo L.) under Inceptisols

Black gram is a type of legume that is widely cultivated and consumed in various parts of the world. It is believed to have originated in the Indian subcontinent and is one of the oldest cultivated legumes in the world. The field experiment was carried out to during kharif season of the year 2022 at departmental farm of Soil Science and Agricultural Chemistry, College of Agriculture, Latur. The experiment was laid out in randomized block design with three replications and eight treatments viz., T1 (RDF), T2 (RDF + Foliar application of humic acid @ 0.2 % at 20 & 35 DAS), T3 (RDF + soil application of humic acid @ 10 kg ha-1), T4 (RDF + soil application of humic acid @ 15 kg ha-1), T5 (RDF + soil application of humic acid @ 20 kg ha-1), T6 (T3 + foliar application of humic acid @ 0.2% at 20 & 35 DAS), T7 (T4 + foliar application of humic acid @ 0.2% at 20 & 35 DAS), T8 (T5 + foliar application of humic acid @ 0.2% at 20 & 35 DAS). The field study indicated that the nutrient uptake and content and grain and straw yield of black gram crop were significantly influenced due to soil and foliar application of humic acid and RDF. The uptake of N, P and K were recorded at harvest. Significant and maximum uptake of N, P and K were noticed with application of treatment T8 (RDF + soil application of humic acid @ 20 kg ha-1+ foliar application of humic acid @ 0.2% at 20 and 35 DAS), whereas the T1 (RDF) showed least values. grain and straw yield significantly affected due to T8 (RDF + soil application of humic acid @ 20 kg ha-1 + foliar application of humic acid @ 0.2% at 20 and 35 DAS) and the lowest grain and straw yield were recorded in T1 (RDF). Thus, it can be concluded that the soil and foliar application of humic acid increase the nutrient uptake and grain and straw yield. The significantly superior result recorded by treatment T8 (RDF + soil application of humic acid @ 20 kg ha-1 + foliar application of humic acid @ 0.2% at 20 and 35 DAS) next to this treatment T7 (RDF + soil application of humic acid @ 10 kg ha-1 + foliar application of humic acid @ 0.2% at 20 and 35 DAS) was best option. The significant increase in grain and straw yield of black gram was due to application of RDF with soil and foliar application of humic acid which mitigates scarcity, increased absorption effectively and increased photosynthetic activity which leads to higher grain and straw yield.

Olive Performance under the Soil Application of Humic Acid and the Spraying of Titanium and Zinc Nanoparticles under Soil Salinity Stress

Salinity is a major social, economic, and environmental menace in climates with low rainfall and high evapotranspiration, and it influences plant growth and causes restriction to crop production in the world. Additionally, under salinity stress, numerous physiological processes such as photosynthesis, biomass accumulation, and photosynthate transfer are also harshly lessened, and it also limits the absorption of adequate water by plants and leads to a dimension in plant water status. Therefore, the current study was conducted to investigate the soil application of humic acid (HA) at 0, 0.5, 1 and 2 kg/tree alone or in combination with the foliar spraying of 0 mg ZnO2 + 0 mg TiO2, 200 mg ZnO2 + 60 mg TiO2 and/or 300 mg ZnO2 + 80 mg TiO2 through the two successive seasons 2022 and 2023. The results demonstrated that the use of HA alone or in combination with the spraying of TiO2 and ZnO2 greatly improved the leaf chlorophyll, flower number, fruit set percentages, fruit yields in kg or in ton per hectare, fruit weight, fruit size, and fruit firmness. Additionally, the same used treatments greatly improved the fruit content from TSS and oil percentages and also the leaf mineral content from N, P and K, while they minimized the fruit drop percentage and fruit moisture content as compared to control. The most positive influence was observed with the soil implementation of 2 kg HA combined with 300 mg ZnO2 + 80 mg TiO2 in the two experimental seasons.

Residual Effect of Humic Acid, PSB and Phosphorus Nutrition on Soil Chemical Properties after Harvest of Rice Crop under the Subtropical Condition of Jammu

Field experiments were conducted during Kharif season of 2022 at the Research Farm, WMRC, SKUAST- J, Chatha. The soil of the experimental site was sand clay loam in texture, slightly alkaline in reaction, low in organic carbon and available nitrogen but medium in phosphorus and potassium. The experiment was laid out in Factorial RBD with three factors replicated thrice. Twenty treatment combinations comprising of five Humic acid treatments (Control, Soil Application of Humic acid @ 2.5kg/ha & 5kg/ha (Market ready), and Soil Application of Humic acid @ 2.5kg/ha & 5kg/ha (FYM), two PSB treatments (With and without PSB) and two levels of Phosphorus nutrition (100% Recommended N:100% Recommended P - 15:40 kg/ha and 100% Recommended N:75% Recommended P - 15:30 kg/ha). The utilization of Humic acid at a rate of 5 kg/ha, sourced from both Market Ready and Farm Yard Manure (FYM), combined with seed treatment employing (PSB) and a nutrient application of 100% recommended nitrogen (N): 100% recommended phosphorus (P) - 15:40 kg/ha, exhibited a more pronounced and favorable residual impact on soil properties. This was evidenced by notable improvements in organic carbon, available nitrogen, phosphorus, and potassium levels, surpassing their initial values but shows in non-significant results. Furthermore, this treatment employing humic acid application, PSB & Phosphorous nutrition showed improvement in seed yield and straw yield but failed to show significant results in residual rice crop.

Mitigation of water stress in broccoli by soil application of humic acid

The main challenge to plant productivity is water scarcity, which is predicted to get worse with climate change, particularly in arid and semi-arid areas. Humic acid could improve plant tolerance to mitigate drought damage, which is an effective strategy to improve crop production and agriculture sustainability under limited water conditions in these regions, but its effective application rates should also be established. Thus, two field experiments were carried out at the Qaha Vegetable Research Farm in Qalubia Governorate, Egypt, during the two seasons of 2020–21 and 2021–22 on clay soil. The present study investigated the effect of three rates of humic acid application (0, 4.8, and 9.6 kg ha-1) on growth, yield, and quality of broccoli cv. Montop F1 hybrid under well-watered and drought conditions. Drought was induced by missing alternate irrigation. Soluble humic acid as potassium-humate was applied three times with irrigation water at the time of the first three irrigations of drought treatment. Water-stressed plants had a decrease in growth, yield, leaf chlorophyll, and nutrient content, while they showed an increase in the contents of leaf proline and curd dry matter and total soluble solids as well as water use efficiency, in both seasons. Soil application of humic acid was effective in mitigating the adverse effects of water deficit stress on the growth and yield of broccoli. Water-stressed plants had the highest WUE value (9.32 and 9.36 kg m3−1 in the first and second seasons, respectively) when the maximal humic acid rate was applied. Humic acid at a high level (9.6 kg ha−1) had the most promising results and represents an opportunity that must be applied to improve broccoli yield and its production sustainability in arid and semiarid regions.

Effect of Humic Acid from Vermicompost and Commercial Source on Growth, Yield and Quality of Groundnut (Arachis hypogea L.)

A pot culture experiment was conducted in the year 2017 at Main Agricultural Research Station, University of Agricultural Sciences, Dharwad to study the impact of soil and foliar application of humic acid from vermicompost and commercial source on growth, yield and quality parameters of groundnut variety GPBD-4 by adopting completely randomized block design with thirteen treatments and three replications. The highest plant height (36.83 cm), LAI (0.96) and relative chlorophyll content (34.82) was recorded in the treatment which received soil application of humic acid from vermicompost @ 20 kg ha-1 in combination with the foliar spray of 0.2% at 30 DAS. Similar trend was observed in yield and quality parameters of groundnut. Significantly highest number of pods plant-1 (24.00), pod yield plant-1 (14.80 g plant-1), oil content (46.12%) and crude protein content (25.38%) was also recorded in the same treatment. The results revealed that there is a statistical increase in the periodical observation, yield and quality of groundnut with the additional application of humic acid extracted from vermicompost over the recommended package of practice.

Responses of tomato hybrid cultivars to soil application of humic acid under greenhouse conditions

Abstract Responses of three tomato (Lycopersicon esculentum Mill.) hybrids viz. 'Luanova', 'Savarona' and 'Tessera' to various doses (0, 0.5, 1.0, 1.5 and 2.0 g L-1) of soil application of humic acid (HA) were evaluated in terms of plant growth, productivity and quality of fruits, under greenhouse conditions, during 2011-12 and 2012-13. In addition to improved quality characteristics, higher values for yield and yield components were recorded for tomato fruits harvested from plants of 'Tessera' cultivar compared to those harvested from other hybrids tested, regardless of growing seasons. Plants from 'Luanova' cultivar were, however, earlier in fruiting with higher number of fruits per plant. Soil application of HA presented positive effects on yield and physicochemical quality of tomato fruits irrespective of the dose of HA and the cultivar investigated, in both seasons. Soil application of HA at higher dose 1.5 g L-1 exhibited better results in all the three tomato cultivars tested, in terms of their vegetative and reproductive growth, and significantly improved the physicochemical quality of their fruits. Conclusively, the tomato hybrid 'Tessera' was found suitable for cultivation under greenhouse conditions while soil application of aqueous solution of HA @ 1.5 g L-1 substantially resulted in higher production of quality tomato fruits.

Effect of Humic Acid Addition and Urea Foliar Spraying on Shoot Characteristics and Chemical Content of Olive Sapling Cv. Khistawi

The experiment was conducted in the lath house belonging to the Department of Horticulture and Landscape Gardening, College of Agriculture, Anbar University, from 1/3/2022 to 15/11/2022 to determine the effect of soil application of humic acid at three levels (0, 10, 15 g sapling−1), respectively, and foliar spray of urea fertilizer at three concentrations (0, 10, 15 g L−1), respectively, and their interaction on the vegetative growth characteristics and leaf mineral content of Khistawi olive saplings. The results showed a positive effect of adding humic acid on most of the vegetative and characteristics and mineral content of the leaves. Adding (15 g sapling−1) resulted in a significant superiority in stem diameter, leaf area, new shoot lengths, percentage of nitrogen, chlorophyll content, carbohydrates, and leaf dry matter, with 4.236 mm, 5.190 cm2, 7.684 cm, 1.824%, 76.739 mg 100 g−1, 7.094%, 47.878% respectively compared to the control treatment. Foliar spray of urea fertilizer at concentration (15 g L−1) resulted in a superiority of the mentioned characteristics above when adding humic acid, reaching 4.530mm, 5.607 cm2, 8.066 cm, 1.844%, 77.578 mg 100 g−1, 7.190%, 48.126% compared to the control treatment. The interaction between the studied factors showed a similar behavior to the individual factors for all studied characteristics.

Plant growth regulators affecting canola (Brasica Napus L.) biochemistry including oil yield under drought stress.

The objective was to test the effects of PGR on canola (Brassica napus L.) biochemistry including oil yield under drought stress. A two-year (Y1 and Y2) split plot field experiment on the basis of a randomized complete block design with three replications was conducted. The main factor was, drought stress levels, including irrigation after areduction of 40 (D1), 60 (D2) and 80% (D3) of field capacity (FC) moisture, and the sub-factor was PGR including control (S1), soil application of humic acid (S2), foliar applications of amino acid (S3), fulvic acid (S4) or seaweed extract (S5), and the combination of all PGR (S6). Although drought stress significantly decreased plant chlorophyll contents (a, b and total), oil percentage and oil yield, PGR significantly increased them. The D3 treatment, compared with control, decreased crop oil yield by 48.67 and 35.29% in the first and second year, respectively. However, treatment Y2D3S6 significantly increased oil percentage (43.10%) compared with control (40.97%). The PGR increased seed oil yield, in D3, by a maximum of 254kg ha-1. The PGR numerically (p ≤ 0.0886) increased proline to 6.14 mg g-1 LFW (Y1D3S6) compared with control (4.79 mg g-1 LFW). The PGR also significantly increased sugar content to 17.05 mg g-1 LFW, significantly different from thecontrol (12.95 mg g-1 LFW). In conclusion, the tested PGR can improve the biochemical properties (quality) including oil yield of canola in drought stress conditions, which is of economic and health significance.

Foliar applications of ascorbic and citric acids with soil application of humic acid for improve growth, yield and fruit quality of grape

Foliar applications of ascorbic and citric acids with soil application of humic acid for improve growth, yield and fruit quality of grape

Morphological Growth of Soybean (Glycine max L.) Treated with Soil Application of Humic Acid under Different Cultivation Periods

The demand of organic cultivation of plants is increasing and soil application of organic fertilizer reduces the hazardous usage of inorganic fertilizer and Humic acid is an organic compound derived from plant and animal residues and microbial cells with long-term physical, chemical, and biological processes. In addition, ultivation of soybean in Kurdistan region is not in a wide value therefore, the objective of this study was to determine the impact of soil application of different rates of Humic acid as an organic fertilizer on the growth characteristic of soybean cultivated and determining the best cultivation period for soybean growth. The experiment was conducted in randomized complete block design with two factor treatments and 3 replication, the first factor was one dose soil application of four different Humic Acid rates (HAR) which were (0 (control), 2,4,6,8 g/L) and two cultivation period (CP) which were cultivation Period 1 (CP1) on 15 May 2022 and cultivation Period 2 (CP2) on 1st of June 2022. Observations were made against the growth parameters of plant height number of branches, leaf area, root length, shoot fresh weight and shoot dry weight. The effect of soil application of humic acid rates (HAR) was highly significant on the plant height and root length and significant on the No. of branches, shoot fresh and dry weight. While, cultivation period insignificantly affected the growth parameter except for leaf area. was significant. The maximum plant height, number of branches, leaf area, root length, shoot fresh and dry weight were observed with soil application of 8 g/L of humic acid which were (82.83 (cm), 23.33, 8815 (mm2), 68.83 (cm), 503.33 (g) and 190.00 (g) respectively. The highest plant height (72 cm), number of branches (18.87), leaf area (7714 mm2), root length (57.13 g), shoot fresh (263.67 g) and dry weight (102.93 g) were observed when the planted cultivated in 1st period (CP1) compared to CP2.

Effect of Potassium humate fertilizers on soil nutrients and productivity of Rice crop in vertisols of Southern India

Humic acid is an eco-friendly product needed in lesser quantity when compared to other chemical fertilizers and manures. A field experiment was conducted for three Kharif seasons (2019, 2020 and 2021) at Regional Agricultural Research Station, Nandyala, Andhra Pradesh to study the effect of potassium humate fertilizers on soil quality and productivity of Rice crop in scarce rainfall zone of Andhra Pradesh, India. Applications of potassium humate with different doses of fertilizers showed a significant effect on selected soil characteristics. The levels of available N, P, K, and micronutrients like Fe, Zn, Cu and Mn in soil increased with different humic treatments. Significantly highest plant height, productive tillers per hill, panicle length and number of grains per panicle was observed with treatment (T4) 100% RDF + Soil application of humic acid @ 30 kg ha-1at tillering, panicle initiation and at harvest stages of crop over other treatments. Highest grain and straw yield of 6074 & 8374kg ha-1 respectively, was recorded with treatment T4 (100% RDF+30 kg ha-1Humic acid as soil application) which was on par with T2 and T3 treatments. The lowest yield was recorded with T1 (Control) 2453 kg ha-1 in all three years.

Effect of humic acid addition and spraying with ginger rhizome extract on the growth and some chemical contents of apricot seedlings Prunus armeniaca L . cv.

This study was conducted at the slat house of the Department of Horticulture and Landscaping - College of Agriculture / Anbar University, during the growing season of 2021. The effect of soil application of humic acid (H) at 0, 4, 8 ml L-1 and ginger rhizome extract (Z) spraying at 0, 5, 10 g L-1 on some growth characteristics and some chemical contents of apricot seedlings, cultivar Hamawi was studied. Eighty-one two-year-old seedlings were selected that grafted on the stock of the apricot seed. A two-factor experiment (3 x 3) was carried out according to a randomized complete block design (RCBD). The investigation included nine treatments, three replications, and three seedlings for the experimental unit. The results indicated the significant effect of adding humic acid to seedlings in all the studied traits, especially the high-level H2 (8 ml L-1), which achieved the best values for the traits (Branch number, Branch diameter, Branch dry matter, Leaf area, Nitrogen, Phosphor, Potassium). Treatment Z2 (10 g L-1) of spraying with ginger rhizome extract was characterized by giving it the best significant effect of the characters (Branch number, Branch dry matter, Leaf area, Nitrogen, Phosphor, Potassium). The interaction of the study factors was significant for all the studied traits except for the diameter of the branch. The highest values were for the treatments H2Z2 (8 ml L-1 and 10 g L-1) and H2Z1 (8 ml L-1 and 5 g L-1), where the lowest values were in the control treatment (H0Z0) for all the studied traits. Keywords. Apricot, Humic acid, Ginger, Vegetative growth, Chemical content.

Co-application of proline or calcium and humic acid enhances productivity of salt stressed pomegranate by improving nutritional status and osmoregulation mechanisms

Maximizing food production through integrated management of vegetative and root growth is a major challenge to food security and sustainability in the face of population growth, salinity stress conditions and climatic changes specially in arid and semi-arid regions. This study was conducted to evaluate the effect of foliar application with proline (Pro) at 5 mM, calcium (Ca) at 1.5% or control supplemented with soil application of humic acid (Hc) at 0, 15 g/tree on the nutrition status, osmoregulatory mechanisms and productivity of ‘Wonderful’ pomegranate trees growing under salt stress conditions. Soil and foliar treatments were applied three times: at flowering stage (April), 2 months after fruit set (June) and at fruit maturity (August). Individual application of either Hc or Pro or Ca alleviated the adverse effects of salt stress. Moreover, supplemented soil application of Hc with Pro or Ca as foliar application increased significantly leaf Pro, total carbohydrates, N, P, Ca and K contents, as well as K/Na and Ca/Na ratio. While it significantly decreased leaf Na and Cl concentration. Furthermore, supplemented application of Hc resulted in the highest decrease in leaf Na and Cl concentrations by 94.59%, 44.79% when combined with Pro and by 51.35%, 31.28%, when combined with Ca. In addition, Hc treatment led to the highest mean fruit yield by 139.56% and 90.73%, respectively as mean of both seasons for Pro and Ca treatments, respectively. The results suggest that, exogenous Pro and Ca supplemented with Hc can mitigate salt stress in ‘Wonderful’ pomegranate through enhancing osmoprotectants accumulaton.

Growth and Yield of Blackgram [Vigna mungo (L.) Hepper] Crop as Influenced by Humic Acid Application

Background: Among the different grain legumes, blackgram [Vigna mungo (L.) Hepper)] is a well-known leguminous crop popular because of its nutritional quality and suitability for multiple cropping systems. Methods: A field experiment was conducted during Autumn season of 2018 and 2019 at Kalyani, Nadia to evaluate the effect of humic acid (HA) application on growth and yield of blackgram crop. The treatments were: Control (sowing of dry seed) (T1); Seed priming (soaking) in water (T2); Seed priming in 0.5% humic acid solution (T3); Seed priming in 1% humic acid solution (T4); Seed priming in 2% Humic acid solution (T5); Soil application of humic acid @1 kg/ha (T6); Soil application of humic acid @ 2 kg/ha (T7); Soil application of humic acid @1 kg/ha + 10 t compost/ha (T8); Soil application of humic acid @ 2 kg/ha + 10 t compost/ha (T9); Foliar application of 0.01% humic acid solution 25 days after sowing (DAS) (T10); Foliar application of 0.05% humic acid solution (25 DAS) (T11); Foliar application of 0.1% humic acid solution (25 DAS) (T12). Result: Soil application of humic acid along with compost had significant effect on number of pods m-2, though; other yield components such as seeds pod-1, seed index was statistically at par in most occasions. The maximum seed yield (1295.53 kg ha-1 and 1298.47 kg ha-1 in 2018 and 2019, respectively) was obtained from the treatment T9 and the second-best treatment was T8.

Integrative Soil Application of Humic Acid and Foliar Plant Growth Stimulants Improves Soil Properties and Wheat Yield and Quality in Nutrient-Poor Sandy Soil of a Semiarid Region

Sandy soils (containing > 50% sand) are widely distributed worldwide and are characterized by their poor structure, low organic matter, weak hydraulic and nutritional properties, and low crop productivity. Using a 2-year pot experiment, in this study, we investigated the effects of humic acid (HA) as a soil amendment and study two plant growth stimulants (PGSs), zinc oxide nanoparticles (ZnONPs), and L-tryptophan (L-TRP), as a foliar application on wheat grown in nutrient-poor sandy soil. Three HA rates (0 (HA0), 0.2 (HA0.2), and 0.4 (HA0.4) g kg−1 soil) and five PGS levels [control, 50 mg l−1 (ZnONPs50), 100 mg l−1 (ZnONPs100), 0.25 mmol l−1 (L-TRP0.25), and 0.5 mmol l−1 (L-TRP0.5)] were used. The soil hydro-physico-chemical properties, morpho-physiological responses, yield, and quality were measured. HA addition amended the soil structure by allowing rapid macroaggregate formation, decreasing bulk density and pH, and increasing porosity and electrical conductivity, thereby improving soil hydraulic properties. HA0.2 and HA0.4 additions improved growth, yield components, and grain minerals, resulting in higher grain yield by 28.3–54.4%, grain protein by 10.2–13.4%, wet gluten by 18.2–23.3%, and dry gluten by 23.5–29.5%, respectively, than HA0. Foliar application of ZnONPs or L-TRP, especially at higher concentrations compared to the control, noticeably recorded the same positive results as HA treatments. The best results were achieved through the integration of HA0.4 + ZnONPs100 or L-TRP0.5 to the tested nutrient-poor sandy soil. The interactive application of HA0.4 + ZnONPs100 or L-TRP0.5 and the use of mineral fertilizer, which is considered a surplus point in permaculture, can be recommended for sustainable wheat production in nutrient-poor sandy soil.

Influence of humic acid application on onion growth characteristics under water deficit conditions

In this study, effect of water shortage on onion growth and quality was evaluated under soil humic acid (HA) application. Three levels of irrigation namely: a1; 80%, a2; 70% and a3; 60% of field capacity (FC) were supplied to plants in combination with two levels of HA namely: b1; 0 and b2; 100 mg/kg soil, in a factorial and completely randomized design with four replications. The interaction of irrigation and HA was significant on leaf dry weight, vitamin C, calcium, total chlorophyll and bulb flavonoids, while the onion fresh yield was not affected by treatments. Many plant growth traits showed a reducing trend with deficit irrigation levels. The leaf biomass as well as the leaf concentrations of potassium, calcium and zinc were significantly decreased under highest water deficit treatment (60% FC; a3b1 and a3b2) compared to control (a1b1) treatment. Leaf vitamin C and calcium concentration showed almost a similar response in which their highest levels were observed in a1b2 treatment, while the lowest amounts were recorded under higher water shortage (a3b1), and application of HA (a3b2) significantly increased these traits under higher water shortage. The amounts of bulb flavonoids and phenols were increased by deficit irrigation and application of HA further increased their content under highest deficit irrigation. The results indicate that water deficit particularly at highest level reduced onion plant growth, while soil application of HA significantly increased the growth and quality traits including leaf biomass, vitamin C, and minerals like Ca, as well as bulb flavonoids under water deficit conditions.

Improving Phytoremediation Efficiency of Copper-spiked Calcareous Soils by Humic Acid Applications

In current study, the enhanced efficiency of copper (Cu) phytoremediation potential of Calendula officinalis L. was investigated in a Cu-spiked calcareous soil, using foliar and soil application of humic acid. For this purpose, in a greenhouse experiment, seedlings of C. officinalis were transferred to Cu-spiked soils (0, 250 and 500 mg/kg) and treated separately with soil (soil drench) and foliar (spraying plant leaves) humic acid applications at different levels (0, 10, 20 μM). The humic acid treatments were applied 2 weeks after transferring plant, and eventually the various biochemical-physiological traits and phytoremediation indices of Cu in C. officinalis were measured at (specific) time points. According to the results, C. officinalis grew normally without any toxicity signs in Cu-spiked soils, however with increasing the Cu levels, the dry weight biomass decreased and antioxidant enzymes activities increased. Both foliar and soil humic acid application in Cu-spiked soils increased dry weight biomass, photosynthetic pigment contents, Cu concentration, and bioconcentration factor (BCF). Furthermore, the application of this organic substance, obviously moderated the Cu stress since the antioxidant enzymes activities reduced compared to the control. Based on the results, the obtained translocation factor (TF) and BCF values of Cu, which were >1, indicated that this plant is a Cu-hyperaccumulator, which could extract Cu via phytoextraction mechanism. Generally, the results of this study showed that, among the humic acid treatments, application of 20 μM (especially soil drench application) had the best effect on increasing Cu phytoremediation efficiency in the studied soil and it recommended to enhance the efficiency of Cu phytoremediation in calcareous soils.

Indole-3-Acetic Acid and Humic Acid Increase the Bio-Degradation of Diesel Oil in Soil Polluted with Pb and Cd

Introduction: Soil remediation is one of the most important fields in environmental studies. This study was conducted to investigate the effect of indole-3-acetic acid (IAA) and humic acid (HA) on increasing the bio-degradation of diesel oil in soil polluted with (lead) Pb and cadmium (Cd).
 Materials and Methods: Treatments included foliar application of IAA (0 (control) and 30 ppm) and soil application of HA (0 (control) and 200 mg/kg soil) in the soil contaminated with Cd (0 (control), 10 and 15 mg/kg soil), Pb (0 (control) and 1600 mg/kg soil), and diesel oil (0 (control), and 8% (W/W)). The sunflower was planted in all soil samples. The plants were harvested after 70 days and Pb and Cd concentrations of plants were measured using Atomic Absorption Spectroscopy.
 Results: Foliar application of IAA at the rate of 30 mg/l significantly increased the Cd and Pb phytoremediation by 14.8% and 13.4%, respectively. For HA application, it was increased by 11.3% and 10.2%, respectively. A significant increase was found in degradation percentage of diesel oil in soil by 12.6%, when the soil was treated with 200 mg HA/kg soil.
 Conclusion: It can be concluded that application of organic amendments such as IAA or HA can be a suitable way for increasing plant growth and increasing plant phytoremediation efficiency, especially in the soil contaminated with diesel oil. However, the phytoremediation efficiency is dependent on the plant physiology and the type of soil pollution that should be considered.

Performance of rabi blackgram (Vigna mungo L.) to soil amendments and irrigation schedules

Field trial was carried out in split plot design at Advanced Post Graduate Centre, Lam, Guntur. The treatments comprised of irrigation schedules as main plots viz., one irrigation at pre-flowering stage (I1), one irrigation at pod formation stage (I2), two irrigations at pre-flowering and pod formation stages (I3) and soil amendments as sub plot treatments viz., soil application of humic acid @ 20 kg ha-1 (S1), soil application of hydrogel @ 2.5 kg ha-1 (S2) and soil application of FYM @ 5 t ha-1(S3). Among different irrigation schedules I3 was found to be superior in recording the highest growth parameters when compared to other two irrigation treatments. Maximum yield was recorded with (I3) which was comparable with (I1). Higher water productivity was realized with one irrigation at pre-flowering stage (I1) when compared to two irrigations at pre-flowering and pod formation stages (I3). Soil amendment hydrogel @ 2.5 kg ha-1 was found to be better in recording higher growth and yield parameters when compared to FYM @ 5 t ha-1. Significant difference in water productivity of blackgram was not observed with regard to soil amendment treatments.

Effect of Irrigation Intervals and Potassium Humate on Sugar Beet Productivity

Present study was conducted under sprinkler irrigation system at private farm in Al-Salehya Al-gadida city, Al-Sharkia Governorate, Egypt. Two field experiments were conducted during two successive growing seasons 2016/2017 and 2017/2018 to study the effect of irrigation intervals (3, 5 and 7 days) and soil application of humic acid at rates of [0 kg (Control), 2.5 Kg and 5 Kg/Fed] in form of potassium humate on yield and quality of sugar beet (Beta vulgaris L.) variety Nancy (multigerm). A split plot design with three replications was used. Irrigation intervals allocated in the main plots, while the potassium humate levels were arranged in sub plots. Obtained results showed that decreasing irrigation intervals from 7 to 3 days significantly increased diameter and root fresh weight/plant, TSS % and root, top and sugar yields/fed in both seasons. Increasing humic acid rates from zero up to 5 kg/fed increased significantly root length, root diameter, root fresh weight/plant as well as root, top and sugar yields/fed and slightly juice quality in the two growing seasons. Moreover, the highest values of TSS % and sucrose % were recorded with humic acid treatments at 2.5 kg or 5 kg/fed in both seasons. Effect of interaction between irrigation intervals and humic acid applications didn’t reach the 0.5% level of significance concerning root length, root yield/fed and sugar yield/fed in the two seasons, while the effect of interaction on TSS %, sucrose %, purity % and top yield/fed didn’t reach the level of significance in the first season only.