Changes in biochemical and morphological characters of garden cress (Lepidium sativum L.) as affected by foliar application with casein amino acid and salicylic acid under greenhouse conditions

Abstract

Foliar feeding of plants can effectively supplement soil fertilization. The effects of foliar application of different levels of casein (CSN: 0, 50, 100 and 150 mg. L1) and salicylic acid (SA: 0, 75, 150, and 300 mM) were investigated on some vegetative and reproductive growth as well as pigments, phenolic compounds and total antioxidants content indices of garden cress (Lepidium sativum L.) at greenhouse condition. It was observed that CSN applied to at 50 mg. L1 resulted in the highest stem and root fresh weights, stem dry weight, and diameter of the main stem. Also, the highest chlorophyll b content was obtained in plants treated with 50 and 100 mg. L1 CSN. In addition, the application of 100 mg. L1 CSN resulted in the highest leaf nitrogen and phosphorous content, while the lowest values were recorded in the control. The results show that SA application exerted a significant effect on the plant height, leaf fresh and dry weights, stem fresh and dry weights, and the number of florets. The highest plant height and leaf fresh weight were obtained in plants treated with 150 and 300 mM SA. Furthermore, levels of 75, 150, and 300 mM SA application significantly increased leaf dry weight, and chlorophyll b. As well, applications of 150 mM SA led to higher stem fresh and dry weights than the control. Moreover, the number of florets in the levels of 0 and 150 mM SA were higher than in other treatments. Overall, the results suggested that spays of CSN and SA, which showed better growth characters, could be more appropriate for application in garden cress spraying programs.