Sunflower Growth and Development Depends on Fertilizer

Abstract

Increasing rates of applying mineral fertilizers under sunflower affect the indicators of fertility and agro-ecological condition of the soil. Also, this action can affect the growth and development of the plants themselves. In particular, the onset of the main phases of growth and development, the dynamics of height, density of plants, the spread of weeds in his crops. The purpose of the research is to study the influence of different rates of mineral fertilizers on the growth and development of sunflower crops. The options differed by the fertilization system: 1. N45P45K45, 2. N90P45K45, 3. N45P90K45, 4. N45P45K90, 5. N45P45K45 + liming and a control option without fertilizers. Nitroamofosk mineral fertilizer was applied to pre-sowing cultivation. The introduction of mineral fertilizers led to a lengthening of the sunflower growing season and an extension of the period until the crops are ready for harvesting. Yes, otherwise, with the option without fertilizer application, the dosage of sunflower supplements was delayed by 3 days for the application of N45P90K45, for 4 days for the application of N45P45K90, for 5 days for the application of N45P45K45 and N45P45K45 + liming, and for 10 days for the application of N90P45K45. The greatest increases in the height of sunflower plants by phases of growth and development were established on the fertilizer option N90P45K45, where the combination of double application of mineral nitrogen is manifested. In the flowering phase of the sunflower in this variant, its height was 180 cm. The highest field germination of seeds was achieved by the fertilization variants N45P90K45, N45P45K90 and N45P45K45 + liming - 92.0%, and the lowest - from the control variant without fertilization - 86.7%. At the end of the sunflower growing season, the highest plant density was 68,000 plants/ha and the highest percentage of plant survival was the N45P45K45 + liming option, and the lowest was the control option without fertilization. However, the variant N45P45K45 + liming provided the highest number of weeds in the phase of full emergence and leaf formation.