Using Spirulina Extract as a Natural Bio stimulant to Improve Yield and Fruit Quality of Valencia Orange Trees

Abstract

This experimental was carried out on Valencia orange trees grown in private orchard located at Belbis district, Zagazig governorate, Egept during two consecutive seasons of 2022 and 2023. The trees were planted 5 x 5 meters apart. The texture of soil is calcareous sandy soil. The present study aimed to improve the yield and fruit quality of Valencia orange trees through foliar application of Spirulina algae extract at 1, 2, 3 and 4 cm/ L water. Trees were sprayed three times starting at the first week of March, May and July. The results showed that 4 ml/L proved to be the most effective concentration for achieving maximum improvements in most studied parameters, while 3 ml/L often produced statistically similar results and may therefore represent a more economical alternative under practical field conditions. Overall, Spirulina platensis can be recommended as a sustainable agricultural practice for enhancing citrus production and fruit quality due to its rich content of nutrients, amino acids, antioxidants, vitamins, and natural growth-promoting substances.