Study the effect of growth improver and chemichal fertilizer application on growth and yeild of Solanum tuberosum

Potato is the fourth most important food crop in the world that plays an important role in people feeding. This crop is a source of carbohydrates, protein and essential amino acids for human being and it is one of the important tuber plants. Low yield of crops in many countries often related to the deficiency of soil nutrients. Chemical fertilizers have an important role in improving yield and quality of potatoes. However, excessive use of chemical fertilizers is associated with many health and environmental problems and pollution in water and soil. This study was conducted to evaluate the effect of organic fertilizers and growth promoters on potato (cultivar Milva) yield to reduce the consumption of chemical fertilizers.
Experiment was conducted at the Agricultural Research Station of Gonbad Kavous University in a randomized complete block design with three replications in 2016. Treatments included the use of nitrogen, phosphorus and potassium to amount of common use of region (100 NPK), 100 NPK Humic acid (HMC), 100 NPK Equilibrate vegetative organic (EVEO), the use of nitrogen, phosphorus and potassium at a rate of half of the region convention (50 NPK) HMC, 50 NPK EVEO, application of EVEO and HMC alone. Traits of tuber number plant-1, fresh and dry weight of tubers plant-1, plant fresh weight ha-1, biological yield, tuber yield, and harvest index were measured.
the results indicated that application of HMC and EVEO with chemical fertilizers significatly increased tuber number plant-1, tuber weight plant-1, biological yield, tuber yield, and harvest index; but they had no significant effect on plant weight. The highest tuber number plant-1, dry weight of tuber plant-1, biological yield, tuber yield, and harvest index were obtained in 100 NPK EVEO; although there was no significant difference with treatments of 100 NPK HMC and 50 NPK EVEO. The lowest amount of these traits were achieved in the treatment 100 NPK. However, it had no significant difference with treatments of application of EVEO and HMC alone.
Based on these results, the use of EVEO can reduce consumption of chemical fertilizers by 50%. Also, significant difference was not observed between chemical fertilzer treatment (100 NPK) and application of EVEO and HMC alone. Therefore, use of these organic materials can increase the absorption and efficiency of nutrition and consequently reducution of the consumption of chemical fertilizers will help to reduce environmental pollution.