The effect of shoot part treatment on the growth of pulai (Alstonia scholaris) cuttings with the water rooting technique

The success of developing plantation forests relies on obtaining high-quality seeds, achievable through generative and vegetative propagation. However, some plants face constraints with generative methods, prompting the exploration of vegetative propagation alternatives. Pulai seeds (Alstonia scholaris) were used for vegetative seed propagation through the use of cuttings in this study. Genetic and environmental factors were identified as significant determinants affecting cutting propagation success. The research aimed to assess how different shoot parts impact Pulai plant cutting growth using the Water Rooting Technique (TWR), known for its simplicity and minimal requirements. Employing a randomized block design with three treatments (shoot tips, mid-shoots, and shoot bases) replicated three times, each treatment combination included 50 cuttings. Observations focused on parameters such as percent growth, shoot growth time, shoot height, root length, total dry weight, shoot dry weight, root dry weight, and shoot-to-root ratio. Statistical analysis using Analysis of Variance (ANOVA) indicated significant differences, confirmed by the HSD follow-up test. The mid-shoot treatment proved to be the most effective method in influencing all observed parameters, highlighting its importance in fostering Pulai cutting growth.


Introduction
One factor that determines the success of plantation forest development is the procurement of quality seeds.Quality seeds can be obtained from the results of generative and vegetative propagation.However, several plants have problems procuring generative seeds, so one alternative for procuring these types of seeds is to carry out vegetative propagation of plants.One of the commonly used vegetative propagation is vegetative propagation by cuttings.
The advantage of vegetative propagation by cuttings is that the resulting plants will be the same as the parent plant; the provision of seeds can be done at any time with sufficient quantities according to planting needs and does not depend on climate.The basic principle of vegetative propagation by cuttings 1315 (2024) 012072 IOP Publishing doi:10.1088/1755-1315/1315/1/012072 2 aims to obtain roots and shoots on cuttings that can grow.Genetic and environmental factors influence the growth of roots and shoots on cuttings.
Genetic factors (plant material factors) include the content of food reserves in the cuttings tissue, the age of the plant (mother tree), endogenous hormones in the cuttings material, and the level of juvenility.Each type of plant has a varying ability to be propagated by cuttings.The growth of cuttings is influenced by the interaction between genetic factors and environmental factors [1,2].Genetic factors, especially the physiological condition of the cutting material, especially the age and part of the cutting material used.According to [2], there are variations in the content of compounds from the base to the tip of the shoot material of the cuttings, this results in differences in the capacity for the formation of roots and shoots on cuttings.The reduced potential for root and shoot formation in older parts is due to low phenol levels, while phenol functions as a cofactor or auxin synergist in root initiation.
Environmental factors include media, temperature, humidity, and light intensity [1,2,3].The types of media commonly used for vegetative propagation by cuttings are solid and liquid media.Commonly used solid media are soil and sand, but using them on a large scale can damage the environment, so it is necessary to look for other alternatives, such as solid media, including water.Water can be used as an alternative medium for breeding cuttings.This technique is known as the Water Rooting Technique [1,2,3].
The Water Rooting Technique (TWR) is simple because it does not require special tools or special skills for its application.Another advantage of TWR is that it saves water in its use, so there is no need for watering and weeding, but not all types of plants can be propagated by this technique [2].Vegetative propagation by cuttings is applied to obtain seeds with the same genetic characteristics as the parent plant.Seedlings can be produced at any time, stand growth is more uniform, and productivity can be increased when using superior varieties.One of the plants used in this study is the type of island (Alstonia scholaris).
Pulai has a riding root, and the bark in the island's plants is light brown and contains a milky white sap on the inside of the bark.Old stems are very brittle and easily peeled off.This plant is tolerant of a wide range of soil types, and growth is affected by the presence of water.This plant can grow on critical lands, so this plant is a type of greening plant [2].The purpose of this study was to determine the effect of the treatment of shoots on the growth of the cuttings of Pulai using the TWR, as well as to analyze the correlation value of the Pulai plant with other parameters.

Preparation of water rooting techniques
The water rooting technique uses a plastic container-sized 30 cm x 20 cm x15 cm and then filled with water up to 10-12 cm high.Bed for cuttings using styrofoam sized 30 cm x 20 cm x 1.5 cm.

Preparation of cutting materials
Cutting materials were obtained from orthotropic branches of the pulai orchard at Nagrak Nursery, Office for Standard Implementation of Environment and Forestry Instruments, Ministry of Environment and Forestry (MoEF) in Bogor West Java, Indonesia.The orthotropic branches were cut and divided into three sections: the base, middle, and top cuttings were about 5-7 cm.Each treatment consisted of 50 pieces of cuttings.Half of the left area was reduced from its original size to reduce transpiration.The cuttings were placed in a bucket filled with water.The cuttings were planted in styrofoam according to the treatment with a distance of 5 cm x 5 cm.Styrofoam is to be floated inside a container with the base of the cutting sinking in water.The container was placed in a greenhouse with a KOFFCO system facility.

Data collection
A study on the propagation of pulai was carried out for five months from October 2022 to February 2023 at BPSILHK (Office for Standard Implementation of Environment and Forestry Instruments), greenhouse, and nursery in Bogor, West Java.Observations on the growth time of Pulai cuttings were carried out three days after the cuttings were planted until they were six weeks after planting, and other observations were made at the end of the study (3 months).The parameters observed were survival percentage, sprouting time, shoot height, root length, total dry weight, dry weight of the shoots, dry weight of the roots, and shoot-root ratio.

Data analysis
The data of shoot cutting performance were analyzed using a variance test to figure out whether were significant differences in shoot part cutting treatment.Data were analyzed for normality using Kolmogorov-Smirnov to determine the type of variance test to be carried out.Before Anova, the percentage data set was arcsine-transformed to meet the normality assumption.

Cutting ability
Based on the results of this experiment, pulai is one type that is easily developed vegetatively by cuttings using TWR.This can be seen from the average percentage of growth, sprouting, and rooting above 90% (90.67-96.58%)(Figure 1).The middle part of the cutting material gives the best response on survival, sprouting, and rooting abilities.The middle and end groups gave better results than the bottom.Even so, statistically, the variation of part of the shoot does not give a significant difference in survival, sprouting, and rooting abilities.The other media for the propagation of pulai cuttings have also been used, including sand, cocopeat, husk charcoal, or a combination [4].The water rooting technique can be used as an alternative because the rooting technique still gives better results.The results of research [7] show that the position of the cutting material influences the ability to be removed and the growth rate of the shoot cuttings.The best results were obtained from shoot cuttings from a position of 100-150 cm (P3) with a finished percentage of 87.50%, the required percentage was 85.42%.Other research [8] shows that the origin of the middle cutting material produces better growth than the origin of the upper and lower cutting material.This is because cuttings from the middle leaves of the mother-in-law's tongue plant produce more adventitious roots than cuttings from the upper and lower leaves.Plants have different rooting abilities caused by genetic factors, which depend on the type of plant.According to [9] that at the beginning of root formation there is a process of differentiation of meristem tissue which will become root primordia.This statement is also in accordance with research on giving IBA ZPT to cuttings of mother-in-law's tongue (Sansevieria trifasciata var.Lorentii) conducted by [10] which stated that the middle cuttings produced the best response for the variables of root emergence time, number of roots, root length, number of shoots, and weight.wet tuna.In addition, Hardjanti's research [11] reported that Adenium cuttings originating from the middle produced better root growth than cuttings originating from the top or shoots.

Shoot cutting performance
The shoot-root ratio describes the balance of plant growth [6].Propagation of pulai cuttings using the water rooting method showed good growth because the shoot-root ratio of the three materials used was 1-3 (Table 1).This means that pulai propagation using the water rooting technique can be used in all cuttings material conditions because it shows balanced growth.Nevertheless, the biomass produced from the three is significantly different.The use of material cuttings in the middle can be preferred.This was because the middle part of the cutting material gave the best response and was significantly different from the others on five observation parameters: short sprouting time, shoot height, total dry weight, shoot dry weight, and root dry weight (Table 1).In contrast, the cuttings base material gave the smallest response.This is presumably due to internal factors from differences in the cuttings' material.The middle part is thought to contain more or more balanced food reserves in terms of carbohydrate, fat, protein, and growth regulatory hormone, which is better than the base and shoot tips [1,2,4].This condition causes the middle part to germinate in a shorter time and grow faster to produce the highest total biomass.Applications in the field for mass propagation can use cuttings at the ends and at the base to see the dominant yield and biomass that is closer than the base.

Correlation
According to [6], the relationship pattern between plant parameters can be seen from the correlation value; in this case, it can be stated by analyzing the value of the correlation coefficient in Table 2.A significant positive relationship exists between the percentage of living cuttings and the ability to germinate cuttings and shoot length.This shows that the water rooting technique by keeping and keeping the cuttings alive can provide a stimulus for the ability to sprout and, at the same time, shoot height which is better than the other parameters.Cuttings with good germination ability will also support good shoot height, which a positive correlation indicates.Based on the difference in cutting materials used, the total dry weight of the biomass is more influenced by the roots' dry weight than the shoots' dry weight.

Conclusions
Pulai (Alstonia scholaris) can be propagated vegetatively using cuttings with the water rooting technique, as shown by the percentage alive, sprouting, and rooting >90%.The three tested materials gave a balanced growth response based on the shoot-root ratio.In general, the middle part of the cutting material gave the best response, so the total biomass was obtained the largest compared to the others.

Figure 1 .
Figure 1.Survival, sprouting and rooting rate of A. scholaris cuttings from different shoot part for 3 months observation in water rooting propagation technique.

Table 1 .
The average treatment of cuttings using a water rooting technique.

Table 2 .
The correlation between parameters.