Potatoes, a global dietary staple, face significant cultivation challenges in regions with high carbonate content and low organic matter in their soils, particularly in central and southern Iraq. These challenging soil conditions reduce the availability of crucial nutrients like phosphorus, which is essential for plant growth and energy transfer. Traditional phosphorus fertilizers are often not fully utilized by plants, with a large percentage becoming chemically fixed in the soil. This challenge has led researchers D. A. Mohammed and B. R. Sarheed to explore innovative solutions in their 2023 study, “The Role of BiocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More and Phosphorus in the Growth and Yield of Potatoes,” published in IOP Conference Series: Earth and Environmental Science. Their research investigates how biochar, when combined with phosphorus, can enhance potato growth and yield, presenting a promising pathway to increased agricultural productivity.

The study found a significant increase across various growth parameters when different types of phosphorus-fortified biochar were applied. Notably, sugarcane charcoalCharcoal is a black, brittle, and porous material produced by heating wood or other organic substances in a low-oxygen environment. It is primarily used as a fuel source for cooking and heating.   More (B3) led to the greatest plant height, averaging 41.23 cm, a 38.91% increase compared to the control group without charcoal (B0), which measured 29.68 cm. This positive effect is attributed to sugarcane biochar’s rich content of essential nutrients like phosphorus, nitrogen, and potassium, as well as its ability to improve soil structure and microbial activity. The low pHpH is a measure of how acidic or alkaline a substance is. A pH of 7 is neutral, while lower pH values indicate acidity and higher values indicate alkalinity. Biochars are normally alkaline and can influence soil pH, often increasing it, which can be beneficial More (4.03) and high cation exchange capacity (37.29 cmol/kg) of sugarcane biochar also contribute to better nutrient retention and availability. Interestingly, while the full recommended dose of mineral phosphorus (100%) resulted in a high average plant height of 36.74 cm, adding only 50% of the recommended phosphorus with sugarcane charcoal (F3B3) yielded the highest individual plant height of 44.93 cm, a remarkable 60.4% increase over the control treatment.

Chlorophyll content, a key indicator of plant health and photosynthetic efficiency, also saw significant improvements. Sugarcane charcoal (B3) again demonstrated superiority, increasing leaf chlorophyll content to 43.95 SPAD units, an 18.43% rise compared to the 37.11 SPAD units in the control group (B0). This suggests enhanced nutrient uptake and utilization, leading to more vigorous plant growth. Similar to plant height, the combination of sugarcane charcoal with 50% of the recommended phosphorus (F3B3) achieved the highest chlorophyll content at 44.90 SPAD units, a 25.41% increase over the control (F3B0).

The number of main branches per potato plant significantly increased with the application of phosphorus-fortified biochar. Sugarcane bagasse charcoal (B3) resulted in the highest number of branches, averaging 3.20 branches per plant, an 85.83% increase over the control (B0), which had only 1.722 branches per plant. This substantial improvement underscores biochar’s role in promoting robust vegetative growth. The most effective combination was sugarcane charcoal with 50% of the recommended phosphorus (F3B3), leading to 3.533 branches per plant, a 135.5% increase compared to the control treatment without phosphorus (F2B0).

The dry matter yield of the vegetative part of the potato plant also benefited considerably. Sugarcane charcoal (B3) resulted in the highest dry matter yield of 81.75 g per plant, a 57.21% increase over the control (B0) which yielded 52.00 g per plant. This highlights biochar’s capacity to enhance overall biomassBiomass is a complex biological organic or non-organic solid product derived from living or recently living organism and available naturally. Various types of wastes such as animal manure, waste paper, sludge and many industrial wastes are also treated as biomass because like natural biomass these More production. The interaction between sugarcane charcoal and 50% recommended phosphorus (F3B3) yielded an impressive 97.41 g per plant, a 109.8% increase compared to the control without phosphorus (F3B0).

Perhaps the most impactful finding for agricultural productivity is the significant increase in both total and marketable potato tuber yields. Sugarcane biochar (B3) led to a total tuber yield of 27.55 µg/ha, a 39.39% increase over the control (B0) at 19.77 µg/ha. For marketable tuber yield, sugarcane charcoal (B3) achieved 24.68 µg/ha, marking a 48.05% increase compared to the control (B0) at 16.67 µg/ha. The combination of sugarcane charcoal with 50% of the recommended fertilizer dose (F3B3) proved to be the most effective, resulting in the highest total tuber yield of 31.81 µg/ha (a 77.51% increase over F3B0) and the highest marketable tuber yield of 29.86 µg/ha (a 93.64% increase over F3B0).

These findings strongly suggest that recycling plant waste, particularly sugarcane waste, into biochar and fortifying it with even 50% of the recommended phosphorus fertilizer can significantly improve potato growth and yield, offering a sustainable and effective solution for enhanced agricultural productivity in challenging soil conditions.

Source: Mohammed, D. A., & Sarheed, B. R. (2023). The Role of Biochar and Phosphorus in the Growth and Yield of Potatoes. IOP Conference Series: Earth and Environmental Science, 1252, 012075.