STIMULATION OF GROWTH AND OIL PRODUCTION IN CUMIN PLANT

Abstract

A pot experiment was carried out during two successive seasons (2017/ 2018 and 2018/2019) at Medicinal and Aromatic Plants Research Department in Dokki. The aim of this work was to study the effect of foliar application of phenylalanine (Phe) and p -nitro phenylacetic acid (PNPAA) each of them alone at (0, 50,100 and 150 ppm) on cumin (Cuminum cyminum L.) plant growth, fruits yield, volatile oil production and its major chemical constituents. In general results indicated that, the foliar application of phenylalanine or p-nitrophenylacetic acid significantly increased vegetative growth expressed as (plant height, number of branches per plant) and produced higher fruits yield (g)/plant as well as volatile oil percentage and oil yield compared with control in the two seasons. Moreover, the highest values were obtained from phenylalanine or p-nitrophenylacetic acid at 150 ppm. Cumin plants showed more effective response to p-nitrophenylacetic acid (PNPAA) than phenylalanine (Phe). As for GLC analysis, the results showed that in general the highest percentage of p -menth-1-en7-ol and cumin aldehyde (p -isopropylbenzaldehyde) the main constituents in the volatile oil achieved with the treatment p-nitrophenylacetic acid at 150 ppm. The high concentration of phenylalanine and p-nitrophenylacetic acid (150 ppm) had significant increments in total phenols, total flavonoids and antioxidant activity compared with control. There was a significant increase in phenylalanine ammonia-lyase (PAL) activity compared to control. Also, there was an increment in IAA, GA3 and low level of ABA. It was observed that p -nitrophenylacetic acid (150 ppm) was superior to phenylalanine (150 ppm) in all afore mentioned characters