Abstract
Effects of Plant Growth Regulators on Nutrient Content of ‘Golden Delicious’ Apple
Long-term plant growth regulators (PGR) applications can affect the mineral content of the plants at both the positive and negative directions. In this study, it was aimed to determine the effects of long-term prohexadione-calcium (Pro-Ca), ethephon, GA3 and GA4+7 applications on nutrients, total carbonhydrate (C), C:N and chlorophyll density (Spad) in the leaf of ‘Golden Delicious’ apple variety grafted on M9 rootstock. For this purpose, the same applications was made on the same trees in each year for three years. At the end of the trials, GA3 and GA4+7 treatments was increased N content of the leaves. While N content was determined as 2.16% in control, the GA3 and GA4+7 was determined as 2.34% and 2.35%, respectively. However gibberellin treatments had lower Ca content compared to the others. Especially GA4+7 application increased K/Ca ratio compared to control that it can be created sensitivity to physiological disorders. The ethephon increased P and K content of plant. However, it was detected increasing the K content in ethephon advanced K/Mg ratio, can lead to Mg deficiency. Although effect on microelements content of the apple of PGR was significant except Fe, there are no toxicity or lack when obtained data was compared with the limits. C content and C/N were found to no differences according to the applications.
Keywords
Plant nutrient, ethephon, gibberellin, Pro-Ca