Enhancing growth performance, nutritional status of oat as affected by foliar application of biostimulants under sandy soil conditions

Abstract Biostimulants are essential for sustaining high forage yields and promoting environmental health, especially in semi-arid regions with sandy soil. Oat cultivation has expanded into newly reclaimed sandy soils as part of sustainable agricultural development strategies. A two-year field experiment (2022 and 2023) was conducted at the Research and Production Station of the National Research Centre in the Nubaria region, Behira Governorate, Egypt, to study the effects of biostimulant application on growth parameters and nutrient content of oat varieties grown in newly reclaimed sandy soil. Four treatment types were utilized: control, 50 ml/L of Tryptophan (Trp), 50 ml/L of Ascorbic Acid (AA), and 5 ml/L of Blue Green Algae (BGA) foliar spray applied in two equal doses. Oat varieties (White Oat, Rad Oat, and Joinette) were randomly allocated in sub-plots. The results showed that biostimulant treatments significantly increased all photosynthetic pigments compared to the control. The lowest values for chlorophyll a, b, (a + b) and carotenoids were recorded under control conditions. The highest germination rate was observed under the BGA treatment, followed by ascorbic acid and tryptophan. The highest forage yield was recorded under the BGA treatment, showing an increase of 150–180% compared with the control. Crude protein content increased compared to the control, while total soluble solids (TSS) and total carbohydrates reached 44.238% and 11.157%, respectively. This study clearly demonstrates that the foliar application of biostimulants significantly enhances growth performance, physiological traits, and chemical composition of oats (Avena sativa L.) under newly reclaimed sandy soil conditions.