Investigating the Correlation and Principal Component of Quantitative Traits in Mixed Cropping of Okra and Cucumber

Abstract

Aims: With the aim of Choosing the most appropriate treatment and investigating the relationships between the traits and investigating the correlation and principal component analysis (PCA) of the morphological and physiological traits, an experiment was conducted in the form of a randomized complete block design (RCBD) in 3 replications on mixed cropping of okra and 3 varieties of cucumber in greenhouse.
 Study Design: In order to conduct the experiment, a randomized complete block design was used (RCBD) in three replications.
 Place and Duration of Study: This study was conducted in Damavand region of Iran in 2019-2020.
 Methodology: This experiment was conducted in a metal frame greenhouse where the average temperature of the greenhouse was 25°C and the relative humidity was 40%. During the harvest season, 3 cucumber plants and one okra plant were randomly sampled and recorded, and the numerical value of each trait was recorded based on the average of 3 random plants.
 Results: The results obtained from the correlation coefficients indicated that the trait of dry fruit yield has a positive and significant correlation with the traits of fruit weight and fresh fruit yield. Also, in examining the correlation graph between the traits, dry fruit yield and wet fruit yield traits had positive correlations with chlorophyll a, number of fruits, total chlorophyll and plant height traits. Based on the main components, 4 components accounted for more than 55% of the total variance of the data, respectively, 16% related to the first component, 14% related to the second component, 11% related to the third component, and 10% related to the fourth component. Graphical analysis was used on the data obtained from the experiment. Based on the ranking diagram of treatments in terms of traits, A1B2 (Baker x Mito) and A1B1 (Baker x NEGIN ) treatments were selected as suitable treatments.
 Conclusion: Comparison of the treatments with the okra single cropping treatment showed that doing mixed cropping of okra: cucumber can have a great effect on increasing the level of desirability in various traits in the target crop.