Effect of harvest dates, mycorrhiza, and some biostimulants on some vegetative growth properties and yield of volatile oil for sweet scented geranium plant (Pelargonium graveolens L.Herit.)

The experiment was carried out in one of the fields of Research Station B in the College of Agricultural Engineering Sciences / University of Baghdad - Al-Jadiriya on the fragrant plant for the spring season 2021 in order to study the effect of harvest date, mycorrhiza, bio-stimulants and the interaction among them on some characteristics of vegetative growth and the essential oil yield of sweet-scented geranium plants. The experiment used a randomized complete block design (RCBD) with a split-plot design with three replications. The experiment included three factors, as the factor of harvest dates represents the main panels with two harvest dates, which are 60 and 90 after planting and symbolized by H1 and H2. In contrast, the secondary panels include the treatment of the mycorrhizal fungal vaccine by two treatments, namely, not adding the mycorrhizal fungal vaccine to the root system and adding it with symbols M1 and M2 As for the sub-secondary panels, the treatments include four stimulating factors: the measurement treatment and the spraying of the vegetative mass with the amino acid phenylalanine at a concentration of 300 mg l ̄¹. The treatment of spraying the foliage with moringa leaf extract at a concentration of 10 gm L ̄¹ and the treatment of spraying the foliage with licorice root powder extract at a concentration of 10gm L ̄¹symbolized by B1, B2, B3, and B4 respectively. The results showed the superiority of the H2 treatment in most indicators of vegetative growth, as well as the increase in the percentages of each of the nutrients and volatile oil in the dried leaves and the volatile oil yield in the dried leaves. Treatment M2 significantly increased all vegetative growth characteristics as well as the percentages of nutrients and volatile oil in dried leaves and volatile oil yield in dried leaves. In contrast, treatment B3 showed an increase in the number of main branches, total number of leaves, total leaf area, fresh and dry weight of leaf yield in the plant and the content of The dried leaves of total chlorophyll as well as the percentages of nutrients and volatile oil in the dried leaves of the plant and the yield of volatile oil in the dried leaves. In contrast, treatment B2 had a significant effect in increasing the plant height rate, the number of main branches and the fresh weight of the leaves. It is one of the most prominent triple interaction treatments recorded. The largest increase in all the traits studied above is the triple interaction H2M2B3 treatment, which was characterized by an Bionatura http://dx.doi.org/10.21931/RB/CSS/2023.08.04.69 2 increase in most vegetative growth characteristics, especially the wet and dry weight of leaves and the percentages of nutrients as well as the percentage of volatile oil and volatile oil yield in the leaves. The triple interaction treatment H2M2B4 was also characterized by its recording of Remarkable superiority in both plant height and leaf content of Total chlorophyll and potassium percentage. Keywords: Sweet-scented geranium plant, Harvest date, Mycorrhizae, Biostimulants, vegetative growth, volatile oil.