Improved Corn Yields When Humic Acid Extracted from Composted Manure Is Applied to Acid Soils with Phosphorus Fertilizer

Abstract

Most corn planted on tropical acidic soils suffers substantial yield loss caused by low crop phosphorus (P) uptake. Humic acid is recommended to increase crop P uptake since it is capable of competing with P to be bound to soil adsorption complexes. Humic acid extracted from composted manure (MHA) is a good alternative to humic acid because it is more reactive and has a higher complexation ability compared with leonardite. Therefore, the effectiveness of soil-applied MHA combined with P was evaluated to improve corn yields in acidic soils from the aspect of crop nutrient uptake efficiency and crop physiological performance. Two high-yielding corn cultivars that are highly accepted by Indonesian farmers and resistant to downy mildew disease were subjected to five different types of MHA and P combinations. The amount of P fertilizer was equivalent to 120 mg P2O5 kg−1 soil. The H10P1 produced the most significant result p < 0.05 in terms of total crop dry weight, grain dry weight, and corn yield. The highest efficiency for P uptake in the leaves and grains was found with H10P1 and H5P1, respectively. Although chlorophyll content was not substantially improved, the stomatal apertures 7 weeks after planting (WAP) were significantly increased p < 0.05 with H10P1 and H15P1. The photosynthetic rate and nitrate reductase (NR) activity at 10 WAP were significantly increased p < 0.05 with H5P1 and H10P1, respectively. The results clearly indicated significant increases in the efficiency of crop P uptake and physiological performance for stomatal aperture, photosynthetic rate, and NR activity can highly contribute to higher corn yields.

Leonardites Rich in Humic and Fulvic Acids Had Little Effect on Tissue Elemental Composition and Dry Matter Yield in Pot-Grown Olive Cuttings

“…Humic substances are recommended for increasing crop P uptake since they are capable of competing with P to be bound to soil adsorption complexes [44]. In agreement with this, Kaya et al [45] observed that leonardite enhanced leaf P and yield in maize under P and water stress in calcareous soils.…”

Dynamics of Phosphorus and Biostimulants on Agro-Morphology, Yield, and Essential Oil Profile of German Chamomile (Matricaria chamomilla L.) Under Acidic Soil Conditions of the Western Himalaya

“…P application increased root length and root volume, which corroborates the finding in wheat, where increased availability of P due to application of biochar increased root length by 1.4–1.8 times (Song et al, 2020 ). Likewise, the application of humic acid (75 mg kg −1 ) and P fertilizer (120 mg P 2 O 5 kg −1 air-dried soil) in corn recorded higher root volume and other root attributes compared with the control (Purwanto et al, 2021 ).…”

Squash Yield, Water-Use Efficiency and Nitrate Accumulation as Influenced by the Application of Humic Acid, Geobacillus stearothermophilus SSK-2018 and Wheat Straw in an Arid Land Condition

“…HA has been described to contain organically active functional groups such as the amino, carboxyl, phenolic, hydroxyl, ketone and quinine groups, which play different roles in the soil-plant interface, including the chelation of macro and micronutrients for enhanced uptake by plants that subsequently leads to increased crop yield [29][30][31]. The use of HA in crop production causes increased phosphate uptake, photosynthesis, elongation of root cells, oxygen uptake and the activity of beneficial soil microbes [29,32]. N fertilization of squash and other related crops has been shown to consistently improve crop yields [8,33].…”

“…The reduction of nitrate accumulation in plants due to the application of HA has been associated with the ability of HA to activate some key metabolic events in plants, such as the increased production of reductase enzymes [43,44]. In addition, the use of HA with chemical fertilizer application has been reported to have the potential to significantly improve soil fertility and crop yield [31,32]. Nitrate is made directly available for plant uptake on the application of N fertilizers, while it is only made available after the decomposition of organic materials such as composts, manures and crop straw [42].…”