Some profound experiments The total Se concentrations in the soil, plant straw, and seeds increased with the addition of potassium humate. Furthermore, the total Cr concentrations were reduced after the application of Se and potassium humate. Fe concentration in the straw and seeds varied from one treatment to another, and Mn concentration was reduced in response to the foliar application of Se and potassium humate. Zn concentrations in the straw and seeds of plants were reduced with the application of varying concentrations of Se. Increasing the application rate of Se induced a reduction in the Cu concentration in seeds. In contrast, the simultaneous application of Se and potassium humate increased the Cu concentration in seeds.
Organic fertilizers, such as potassium humate (KHA) and potassium fulvic acid (FA) are used to prevent
plant diseases, improve soil structure, and augment soil nutrient levels .Potassium humate and fulvic acid addition reshaped microbial functions and nutrient levels were found to increase in ginseng soil .Furthermore, the application of potassium humate enhanced seed germination, nutrient uptake, and the growth of seedlings.
Several parameters including NPK concentrations in soil and plants, oat yield, soil organic matter, non-enzymatic antioxidants and total phenols, Se concentration in soil and plants, and Cr, Fe, Mn, Zn, and Cu in oat plant straw and seeds. The additional application of Potassium humate augmented these effects that supplementation increased the availability of N and P in soil and total concentrations in plant straw and seeds.
Potassium humate decreased the requirement of inorganic fertilizer as the maximum cost benefit ratio in
autumn crop was computed when 16 kg potassium humate was applied with 75% of NPK recommended
dose. These results are also partially supported by Dass et al. (2008), who also obtained the best results in terms of yield and net economic return of Brassica oleracea and Capsicum annum crops under application of 50% less NPK with organic fertilizers. According to Khan et al. (2010), the application of humic acid in combination with a 50% less NP chemical fertilizers caused 24 to 47% increase in grain yield over the control and saved valuable high-cost chemical fertilizers.
It is obvious from the results that application of NPK significantly increased tuber yield of potato cv. Cardinal in the presence of potassium humate due to their synergistic effect. Although, all combinations of NPK and potassium humate significantly improved yield attributes compared to alone application of NPK fertilizers but application of 75% of NPK recommended dose coupled with 16 kg potassium
humate per hectare was the most suitable combination because it was found more economical combination among all the treatment combinations. Thus, nutshell of the study is that application of NPK fertilizers along with potassium humate is more profitable and economical for potato growers than alone application of inorganic fertilizers as it enhanced the efficiency of fertilizers, crop yield and net return.