Environmental stress factors determine the distribution, diversity and yield productivity of plants in their environment. Water deficiency and waterlogging, salinity, heavy metals, low and high temperatures, ultraviolet rays, radioactive radiation, mineral nutrient deficiencies, these factors that have a negative impact on the growth and development of plants and yield productivity are known as the causes of abiotic stress. It is estimated that approximately 45% of the agricultural areas in the world are affected by drought and 6% by salinity, and almost one-third of the population is affected by this situation. Poor quality irrigation water, frequent drought conditions, unpredictable weather movements and climate change contribute to the emergence of key environmental stress factors, and these stress factors affect agricultural productivity, especially in developing countries.

Plants give signals to the stress they are exposed to, depending on the duration and severity of the stress. While some plants manage to protect themselves from injury or damage, many of the sensitive ones face great difficulties in coping with these stress factors.

Humic acids (HA) are high molecular weight, brown to dark colored, amorphous, organic substances that are found in varying amounts almost everywhere on the earth, including leonardite, peat, lignite, animal manure, compost, soil and coal. Humic substances act as biostimulants for plant growth by optimizing PH, ensuring better uptake of nutrients from the soil, and increasing the water holding capacity of soil particles.

There are many studies showing positive results on humic acids, which are used to support cultivated plants against stress factors as well as to eliminate or reduce the negative effects of chemical fertilizers used in agriculture.