Kawthar Abou Assali ^*(1), Roula Bayerli ⁽²⁾  and Bassam Al Atalah⁽¹⁾

(1). Sewida Research Center, General Commission for Scientific Agricultural Research (GCSAR), Damascus, Syria.

(2). Horticulture Department,  Faculty of Agricultural Engineering, Damascus University. Damascus, Syria.

(*Corresponding author: Kawthar Abou Assali. E-Mail: kawtharaboassaly@gmail.com).

Received: 10/01/2024         Accepted: 27/03/2024

Abstract

The research was carried out at Urah Research Station, Sewida Agricultural Scientific Research Center, General Commission for Scientific Agricultural Research in Syria for the 2021 agricultural season, using the split plot design with three replicates. Pre-treated Cucumber seeds with salicylic acid (0, 1, 50, 150 mg/l) were planted, then exposed to different irrigation levels (60, 80, 100% of field capacity). Simple correlation and principal component analyses of the resulting data were studied, in order to determine the relationship between productivity indicators and some morphological and physiological indicators under the irrigation levels presented to determine the most important indicators associated with yield. In addition to determine the best concentration of salicylic acid for each of these indicators and productivity. The correlation analysis results showed a significant positive correlation between productivity indicators and all morphological indicators, besides each of relative water content (0.985) and nitrogen concentration indicators (0.965) under 100% field capacity. In addition to a positive correlation of productivity with both the number and weight of fruits indicators. The significant positive correlation between productivity and other morphological and productivity indicators continued under the two levels of water stress applied. As it was observed that the number of leaves, fruits, and weight of the fruits were completely and positively correlated with productivity under 80% field capacity. While the length of stem, number and weight of fruits correlated with productivity under 60% field capacity. Results also indicated that there was a significant positive correlation between productivity and some physiological indicators (proline, soluble sugars, chlorophyll a, chlorophyll b, nitrogen and potassium concentrations) under the moderate stress influence (80% of field capacity), and a significant positive correlation between productivity and proline (0.995) under irrigation level 60% of field capacity. Results of principal component analysis showed that the first and second components expressed the largest proportion of the total variance under all field capacities, and most of the studied indicators were positively correlated with productivity (a sharp angle between the productivity axis and most indicators axes), and in the same direction under all irrigation levels. Treatment with 50 mg/L concentration of SA was located in the same direction, within the positive quadrant, Therefore, 50 mg/L treatment was the best concentration  considering  all mentioned indicators.

Keywords: Cucumber, productivity, correlation coefficient, principal component.

Full paper in Arabic: PDF