Effect of Pinching, Paclobutrazol and Kinetin on the Growth and Flowering of Cassia Occidentalis

The experiment was conducted in lath house of the Agricultural Preparatory School / Abi Ghareq for the spring season 2022_2023 to study the effect of fencing and spraying with paclobuterol and kinetin and its interaction on the growth and flowering traits of Cassia Occidentalis. Where the symbol for pinching is C1 and no edging is C0, the plants were sprayed with three concentrations of paclobetrazole with two concentrations (0, 0.5 and 1 g. L-1) and its symbol is (P0, P1, P2), and the plants were sprayed with kinetin at concentrations (0, 50 and 100 mg.L-1) and its symbol (K0, K1, K2. It was a split-plot factorial experiment (2*3*3) with three replicates using a Complete Randomized Blocks Design (R.C.B.D).Pinching was the main plot and paclobetrazole, kinetin, and their interactions were the subplot in each replication with 18 treatments and five plants per experimental unit (one plant per pot). The averages were compared using the Least Significant Difference L.S.D test at the 5% level, and the results showed excelled of edging on without pinching in the traits of the leaf area (587.75 cm2) and the number of flowering inflorescences (3.33 inflorescences.plant-1), The treatment of paclobetrazole with a concentration of (1 g.L-1) excelled in plant height (17.15 cm), leaf area (346.17 cm2), length of internodes (1.94 cm), and number of inflorescences (2.7 inflorescences. plant-1). While the treatment of kinetin with a concentration of (100 mg.L-1) excelled in length of the internodes (1.66 cm), the diameter of the flower (3.13 cm), while the treatment of Kinetin with a concentration of (50 mg.L-1) excelled in leaf area (630.20 cm2).


Introduction
The genus Senna cassia spp.belongs to the order of Fabales belonging to the Fabaceae family.The genus Cassia contains about 500 species, most of which are used for medical purposes or to decorate streets and parks because of their abundant yellow flowers.The Cassia Occidentalis is one of the most widespread plants.It is characterized by compound, paired, alternating feathery leaves, and the leaflets are from 4 to 6 pairs of opposite leaflets complete with a sharp edge, and the median veins of the leaflets do not divide them in half completely at the bases of the leaflets.Flowers in large yellow cluster inflorescences tending to brown, Horny fruits The leaves and fruits of senna contain anthraquinone glycosides and their derivatives, which consist of Aloe-emoidin and Rhein glycosides, both of which are in free or bound form, and together they form different glycosidic forms.The leaves that are sold commercially contain 2-3% of glycosides A and B together, and 2-4% of the glycoside, which is attributed to the mild colic associated with the action of senna.In general, senna is used as a 1259 (2023) 012045 IOP Publishing doi:10.1088/1755-1315/1259/1/012045 2 stimulant for the muscular layer of the intestinal wall, so it is used as a laxative.Senna is one of the preferred laxatives for the treatment of chronic constipation.Senna differs from other plants, such as castor bean and cactus, in its lack of effect on headaches or dullness when used [1].Growth retardants are used when producing flowering potted plants to obtain a plant with specifications of suitable height, size and shape.Growth retardants are non-nutritional organic materials when used on plants that give a compact plant (compact) that hinders elongation but increases the lateral branches and the plant's content of chlorophyll and nutrients.As it works to hinder the action of gibberellins, and among the growth obstacles are Cycocel, Alar, Paclobetrazole, and others [2].Cytokinines play an essential role in stimulating the process of cell division and specialization in association with auxins [3].It also highlights its importance in many other physiological processes, such as the phenomenon of apical dominance, which affects the process of branching in the plant.The first Cytokinines compound discovered was Kinetin, which is not found naturally in the plant [4], but is one of the products of thermal rotting of adenine.The discovery of kinetin prompted the industrial synthesis of hundreds of compounds similar to it, but kinetin is one of the most common materials used in studies of the physiological effects of cytokines [5].

Materials and Methods
The experiment was conducted in lath house of the Agricultural Preparatory School / Abi Ghareq for the spring season 2022_2023 to study the effect of pinching , pacloprozole and kinetin on the growth traits of senna plant.

The First Factor: Pinching
After planting the plants in the pots designated for them, and when the seedlings reach 6 pairs of true leaves Half of the plants were pinched and the other half of the experimental plants were left without pinching , and the symbol for un-pinching plants is C1, while the pinching plants are symbolized by the symbol C2.

The Second Factor: Spraying with Paclobutrazol (P)
The plants were sprayed 20 days after pinching, with three concentrations, as follows;  Control without spraying paclobetrazole (P0(. Spraying paclobutrazol at a concentration of 0.5 g/L and the symbol is P1.
 Spraying paclobutrazol at a concentration of 1 g/L and symbol P2.

The Third Factor: Spraying with Kinetin (K)
The treatment was sprayed on the leaves until complete wetness and twice: the first one week after the pinching and the second one month after the treatment with paclobutrazol and as follows;  Control without spraying with kinetin , which is indicated by K0.  Spraying kinetin with a concentration of 50 mg/L and its symbol K1.  Spraying kinetin with a concentration of 100 mg/L and its symbol K2.

Plant Height (cm(
Based on the data in Table (1), we can conclude that there were no statistically significant differences in plant height between the pinching treatments, but that spraying with paclobutrazol at a concentration of 1 g.L-1 significantly reduced plant height, from 68.66 cm in the control treatment to 17.15 cm in the lowest-treated group.No discernible variations in effect occurred throughout Kinetin spraying treatments.Because of the bi-interactions between pinching and paclobutrazol spraying, there were noticeable differences in plant height.The C1P2 treatment resulted in the shortest plants at 16.63 cm in height, while the C2P0 treatment resulted in the tallest plants at 69.39 cm in height.There were substantial changes in plant height due to the interactions between fence and spraying with kinetin, with treatment C1K2 having the shortest plants at 30.30 cm and treatment C1K0 having the tallest plants at 37.04 cm.Plant height was significantly affected by the combined action of paclobutrazol and kinetin spraying; plants exposed to the P2K0 treatment grew to a meager 15.33 centimeters, while those exposed to the P0K0 treatment grew to a lofty 71.61 centimeters.Significant differences between treatments emerge in the triple interaction of the study's components.Average plant height was 13.11.cmfor the C1P2K0 treatment and 79.45 cm for the C1P0K0 treatment.

Leaf Area (cm²)
It is clear from the results of Table (2) that there are significant differences between the pinching treatments of Cassia Occidentalis plants, where pinching gave a leaf area of 587.75 cm², excelled on the leaf area of plants without pinching which amounted to 489.19 cm².While spraying with paclobutrazol reduced the leaf area to 346.17 cm 2 when treated with a concentration of 1 g.L -1 and a significant difference from the control treatment, whose plants gave the largest leaf area of 916.85 cm 2 , As for the effect of spraying with kinetin, the treatment was 50 mg.L -¹ excelled by giving it the largest leaf area of 630.20 cm², with a significant difference from the control treatment, which gave the least leaf area of 474.84 cm².The bi-interactions between pinching and spraying with paclobutrazol led to significant differences between the plants, where the C1P2 treatment was characterized by giving the lowest leaf area, which amounted to 235.97 cm 2, compared to the treatments C1P0 and C2P0, which gave the highest leaf area, which amounted to 919.95 cm 2 and 913.75 cm 2 .The interactions between pinching and spraying with kinetin led to significant differences in the average leaf area, where treatment C2K1 gave the highest average of 704.41 cm 2 compared to treatment C1K0, which gave the lowest average of leaf area of 432.66 cm 2 .Also, the effect between spraying with paclobetrazole and kinetin had a significant effect on the leaf area, where the treatment P0K1 gave the highest average leaf area of 1171.29 cm 2 , while P2K0 plants gave the lowest average leaf area of 271.63 cm 2 .In the triple interaction between the factors of the study, we notice that there are significant differences between the treatments, where treatment C1P2K1 gave the lowest average leaf area of 126.10 cm 2 .While treatment C1P0K1 recorded the highest values for the average leaf area, which amounted to 1204.33 cm 2 .

Chlorophyll Pigment (SPAD)
It is clear from the results of Table (3) that there are no significant differences between the pinching treatments of senna plant, while spraying with paclobetrazole gave the highest chlorophyll dye when the treatment was at a concentration of 0.5 g.L -1 , which amounted to 77.39 spad, with a significant difference from the control treatment, whose plants gave the lowest chlorophyll dye, amounting to 60.05 spad.As for the effect of spraying with kinetics, we note that there are no significant differences between the spraying treatments.The interactions between pinching and spraying with paclobetrazole resulted in significant differences between the plants.Where the C1P1 treatment was distinguished by giving the highest chlorophyll pigment , which amounted to 75.82 spad, compared to the treatment C2P0, which gave the lowest chlorophyll dye, which amounted to 59.06 spad.Also, the joint effect between spraying with paclobetrazole and kinetin had a significant effect on the chlorophyll pigment , where the treatment P1K2 gave the highest chlorophyll dye amounting to 80.42 spad, while the P0K1 treatment plants gave the lowest chlorophyll pigment amounting to 58.93 spad.In the triple interaction between the factors of the study, we notice that there are no significant differences between the spraying treatments.
Table 3.The effect of pinching, paclobetrazole, and chitin and their interactions on the chlorophyll pigment (SPAD) of senna plant Cassia Occidentalis.

Internodes Length (cm)
According to Table (4), there are no statistically significant variations in the mean internode length between the pinching treatments of senna plants.There were statistically significant changes in internodal length between the spraying treatments with paclobuterol, with the 1 g.L -1 dosage producing the shortest internodes at 1.22 cm.When compared to the other treatments, the Internodes length after the control group received the longest at 1.94 centimeters.When comparing the results of kinetin spraying, we found notable differences amongst the treatments, with the 100 mg.L -1 treatment yielding the longest Internodes at 1.66 centimeters.The shortest Internodes length (1.43 cm) was seen in the placebo group.Internode length was significantly different amongst the treatments due to the biinteractions of pinching and spraying with paclobuterol, with the C1P2 treatment producing the shortest internodes at 1.20 cm.Interactions between pinching and spraying with kinetin resulted to the appearance of substantial differences in the average length of the internodes on the plant, with the C2P0 treatment giving the longest internodes, reaching 2.08 cm.The C2K2 treatment resulted in the longest Internode length (1.78 cm), while the C2K0 treatment resulted in the shortest Internode length (1.40 cm).Paclobuterol and kinetin spraying showed opposite effects on the average length of the plant's Internodes.When compared to the P0K2 therapy, which resulted in the longest Internodes at 2.26 centimeters, P2K0 treatment resulted in the shortest Internodes at 1.13 centimeters.Treatment C2P2K1 resulted in the shortest Internodes length (1.3 cm) compared to Treatment C1P0K1, which resulted in the longest Internodes length (1.83 cm), due to the triple interaction between the factors of the study.

Number of Inflorescences (Inflorescence. Plant -1 )
The results in Table (5) that there are significant differences between the pinching treatments of Cassia Occidentalis in the average number of inflorescences, where pinching gave a number of inflorescences of 3.33 (inflorescences.plant -1 ), excelled on the number of inflorescences of a plant without pinching, which amounted to 2.9 (inflorescences.plant -1 )While spraying with paclobuterol gave the least number of inflorescences per plant when the treatment was at a concentration of 1 g.Lˉ¹, which amounted to 2.7 (inflorescence plant-1), with a significant difference from the control treatment that gave the highest number of inflorescences per plant, which amounted to 3.39 (inflorescence plant -1 ),As for the effect of spraying with kinetin, we notice that there are no significant differences between the spraying treatments.The bilateral interactions between pinching and spraying with paclobuterol led to significant differences between the plants, where the C2P0 treatment was characterized by giving the most number of inflorescences amounted to 3.81 (inflorescence.plant - ) compared to the C1P2 treatment, which gave the least.The number of flower inflorescences per plant, which amounted to 2.41 (inflorescence.plant - ), The interactions between pinching and spraying with kinetin led to significant differences in the average number of inflorescences, where the treatment C2K0 was distinguished in the number of inflorescences, which amounted to 3.81 (inflorescence.plant -1 ) compared to the treatment C1K0, which gave the lowest number of inflorescences amounted to 2.67.Also, the effect between spraying with paclobuterol and kinetin had a significant effect on the average number of inflorescences, where treatment P0K0 gave the highest number of flower inflorescences amounted to 3.56 compared to treatment P2K1, which amounted to 2.56 (inflorescence plant -1 ),The triple interaction between the factors of the study led to the existence of significant differences between the treatments, where the treatment C2P0K0 gave the most inflorescences rate of 4.11 (inflorescence plant -1 ), while the treatment C1P2K0 recorded the lowest number of inflorescences for the plant, which amounted to 2 (inflorescence plant -1 ).

Flower Diameter (cm)
Table (6) shows that when comparing the various pinching treatments for Cassia Occidentalis, there are no discernible differences.Neither the addition of paclobuterol spray nor the subtraction of the pinching treatments produced any statistically meaningful results.When comparing the two kinetin spraying treatments, we find that the treatment with 100 mg.L -1 produces the largest inflorescence diameter (3.13 cm) compared to the control treatment (3.08 cm).Significant variations were observed between the plants due to the bi-interactions between pinching and spraying with paclobuterol, with treatment C2P1 producing the largest flowers (with a diameter of 3.23 cm) compared to treatment C1P0, which produced the smallest flowers (with a diameter of 3.00 cm).Significant differences emerged as a result of the interactions between pinching and kinetin spraying, with the C2K0 and C1K2 treatments producing the largest inflorescences (3.16 cm and 3.16 cm, respectively) and the control treatment producing the smallest (3.00 cm).Furthermore, there were no statistically significant variations in effect size between the paclobuterol and kinetin spray treatments.Treatment C2P1K0 produced the largest average flower diameter (3.28 cm), while treatment C1P0K0 yielded the smallest average flower diameter (2.84 cm), both as revealed by the triple interaction between the factors of the study.Table 6.Effect of pinching, paclobetrazole, and kinetin and their interactions on the flower diameter (cm) of Cassia Occidentalis.

Table 1 .
Effect of pinching, paclobetrazole, and kinetin and their interactions on plant height (cm) of Cassia Occidentalis.

Table 2 .
The effect of pinching, paclobetrazole and Kinetin and their interactions on the leaf area (cm²) of Cassia Occidentalis Cassia Occidentalis.

Table 4 .
Effect of pinching, paclobetrazole, and chitin and their interactions on the length of the internodes (cm) of Cassia Occidentalis Cassia Occidentalis.

Table 5 .
The effect of pinching, paclobetrazole, and kinetin and their interactions on the number of inflorescence plant -1 of senna plant Cassia Occidentalis.