LED (Light Emitting Diode) Light Provides Positive Effects on Growth and Productivity of Pakcoy Mustard (Brassica Rapa L.)

Plant photosynthesis is strongly influenced by light, carbon dioxide, the availability of water and nutrients found in the soil. In this study, LED light combined with gambelan music Gong Kebyar was applied to pakcoy plants to see its effect on growth and productivity. The LED light that was applied is white, red-blue, and red-white-blue LED light, which is given for 20 hours from 06.00 to 02.00. Gamelan music Gong Kebyar is applied for 3 hours, from 06.00 to 12.00. Variables observed included plant height, canopy area, leaf greenery, root length, and plant biomass. The results showed that white LED light had a negative effect, while the red-blue LED, and red-white-blue light had a positive effect on the growth and productivity of Pakcoy mustard. The use of red-blue LED light combined with gamelan music Gong Kebyar gave the highest value on plant height (27,176 cm), canopy area (1457.59 cm2), leaf greenery (160.03), root length (23.6 cm), and plant biomass (5.05 g). It can be concluded that the use of red-blue LED light combined with gamelan music Gong Kebyar increases the growth and productivity of pakcoy mustard.


Introduction
The indoor cultivation system is a cultivation technique carried out in a room with controlled environmental conditions that can be adapted to the micro-climate of the plant. According to [12] Indoor cultivation systems produce room temperatures that are not as hot as open spaces and can minimize pest disturbances, so that plants can grow optimally. In indoor cultivation systems plants are not optimal in getting sunlight for photosynthesis. To overcome this, artificial light is used to manipulate sunlight. Artificial light used in cultivation must have the right quality so that plants can carry out photosynthesis optimally. In the process of photosynthesis chlorophyll can absorb blue waves (400 -500 nm) to red (600 -700 nm) so that artificial light designed for plant growth must emit these waves [18]. LED light (light emitting diode) has a wavelength of 400 nm -700 nm [1] and does not produce high temperatures so that it can be used to increase plant growth [14].
Many research on the utilisation of LED light in plants has been carried out [28] found that red LED lights had a positive impact on the growth of chrysanthemum plants. While, [27] found that combination of red-blue LED lights gave the best growth of chrysanthemum plants. According to [9] LED lights can speed up the harvest of lettuce, where blue LED lights can stimulate vegetative growth  [11] stated that the combination of red, white and blue LED lights for 16 hours produced many positive effects on the growth of lettuce. The use of white light is thought produce a balanced amount of light spectrum so the photosynthesis processes is running better.
Besides light, other factors that can affect plant photosynthesis are carbon dioxide, water and nutrients. The optimal photosynthesis process will produce maximum plant growth. One of the technologies that have been developed to produce maximum growth in plants is by utilizing sound waves which is commonly called sonic blooms. Sonic bloom utilizes high frequency sound waves to stimulate the opening of stomata [15] so it accelerate the rate of absorption of carbon dioxide, water and minerals in the soil. Naturally, plants get sound sources from natural environments such as animal sounds and sounds that come from daily activities [4] examined the exposure of Balinese gamelan music on pakcoy mustard with different musical nuances, and he was found that Balinese gamelan music with joyful nuances had a positive effect on the growth and productivity of pakcoy mustard. Sonic Bloom also utilized by [20] to increase the productivity of pakcoy mustard. They found that combination of sonic bloom and monochromatic light increased pakcoy production by 40.08%.
Based on those studies, this research was conducted to determine the effect of gamelan music Gong Kebyar combined with LED light on the growth and productivity of pakcoy mustard, and to determine the combination of gamelan music Gong Kebyar and LED light that gave the best growth and productivity to pakcoy mustard. Pakcoy mustard is selected as an object of this research because pakcoy mustard responsive to environmental changes and high demand for consumption. The use of Balinese gamelan music Gong Kebyar is based on the study of [4] and each plant can respond and like different music [24].

Tools and materials
The tools used in the study include growth chamber, analytic scales, oven, thermo-hygrometer, lux meter and sound meter level. The growth chamber is equipped with speakers with a frequency response of 280 Hz -18 kHz, HPL (High Power LED) with 12-18 volt LED drivers 300mA ± 5%. Every 1 Watt HPL has a red HPL specification of 2.2 -2.4 volts 350 mA, blue HPL 3 -3.2 volts 350 mA, and white HPL 3.3 -3.5 volts 350mA. In addition, the growth chamber is also equipped with exhaust and exhaust. The materials used in the study were P1 pakcoy hybrid seedlings, fertile soil, compost, NPK fertilizer, and polybags diameter 25 cm.

Experimental design
This study used a factorial complete randomized design with 3 treatments and 1 control, so that 4 combinations were obtained. Each treatment was repeated 5 times. The experimental treatment were as follows: P1: Combination of gamelan music Gong Kebyar and white LED light P2: Combination of gamelan music Gong Kebyar and blue-red LED light P3: Combination of gamelan music Gong Kebyar and blue-red-white LED light K : Control (without treatment and cultivated at greenhouse conditions)

Implementation of Research
Experiment begins with the preparation of planting media, seed seeding, planting seeds, maintaining plants, giving treatment and observing and measuring parameters. The planting medium used was a mixture of fertile soil and compost with a weight ratio of 50: 50, which was added to the polybag. Seed seeding is done in 10 days using fertile soil planting media. After sowing 10 days, the seeds are transferred to the planting media. The treatment of combination of gamelan music Gong Kebyar and LED light in the growth chamber was carried out 3 days after planting. The treatment is ilustrated in figure 1. The music given to each treatment has same frequency and amplitude

Combination of gamelan music Gong
Kebyar and white LED light The combination of gamelan music Gong Kebyar and blue-red LED light The combination of gamelan music Gong Kebyar and blue-red-white LED light Figure 1. Picture of Pakcoy mustard inside the growth chamber (side view).

Research Parameters
The parameters observed in this research included: 1. Plant height, measured from the base of the stem to the highest leaf and repeated on three different leaves. Height measurements are carried out every week until harvest. 2. The area of the canopy, measured using the image estimation method using Matlab 2017a software.
The image is taken perpendicular to the top using a camera [4]. Measuring the area of the canopy is done every week until the harvest. 3. The greenness of the leaves, measured by green intensity values on the green channel of the leaf image taken [4]. Measuring the greenness of leaves is done at harvest time. 4. The length of the root, measured using a ruler from the base of the root to the tip of the longest root and repeated at three different root tips and then averaged. Measurement of root length is carried out after harvest. 5. Wet weight, measured after harvest using analytical scales. 6. Biomass, measured after harvest by drying the plant oven at 105 o C for 24 hours. The drying results are then weighed using analytical scales [8].

Effect of Combination of Gamelan Music Gong Kebyar and LED Light on the Height of Pakcoy Mustard
The results of analysis of variance showed that the combination treatment of gamelan music Gong Kebyar and LED light did not significantly affect the height of Pakcoy mustard at the age of 0 and 1 week after planting. However, at the age of 3, 4, and 5 weeks after planting, the combination treatment of gamelan music Gong Kebyar and LED light showed a significant effect on the height of pakcoy mustard. The change of height of the Pakcoy mustard in each treatment are ilustrated in figure 2, and the Duncan test results on the height of the pakcoy mustard are tabulated in table 1.    24.8% compared to the control. This is presumably because the intensity of the white light produced is not optimal for carrying out photosynthesis. According to [5] the light absorbed by plants for photosynthesis depends on the wavelength, intensity, and time of irradiation. The light intensity of the LEDs might be smaller than the controls, so that the growth of plants given white LED light becomes obstructed. Thus it can be stated that the treatment of the combination of gamelan music Gong Kebyar and white LED light has a negative effect on the height of the pakcoy mustard.
It can be also seen from table 1 that the combination treatment of the gamelan music Gong Kebyar and the blue-red LED light produced the highest value of pakcoy height. This is in accordance with the  [4] that Balinese gamelan music gong kebyar has a positive effect on the high growth of pakcoy mustard. Beside of music, light availability is an important influence in the cultivation process. According to [25] the red light that applied to plants can affect the elongation of plant leaves which causes the leaves to become long and slender. The red light needs to be combined with blue light which is thought to have a role to inhibit the lengthening of plant organs.
The combination treatment of gamelan music gong kebyar and blue-red LED light increase the height by 1.9% compared to controls. This is presumably due to the combination of gong kebyar music and light blue-red LEDs can accelerate the process of plant photosynthesis. Gamelan music Gong kebyar can stimulate the opening of leaf stomata so that chlorophyll is more optimal in absorbing light, carbon dioxide and nutrients used for photosynthesis. This is in accordance with the statement of [19] which states that music can widen the opening of leaf stomata thus accelerating the absorption of water and minerals and CO2 for photosynthesis. According to [17] in the photosynthesis process of chlorophyll pigments a and b absorb more red and blue light. Thus it can be stated that the treatment to the plant by gamelan music gong kebyar and blue-red LED light has a positive effect on the height of the pakcoy mustard.

Effect of Combination of Gamelan Music Gong Kebyar and LED Light on Canopy Area of
Pakcoy Mustard Based on the results of analysis of variance, it was found that the combination treatment of gamelan music Gong Kebyar and LED light had a significant effect on the canopy area of the pakcoy mustard, so Duncan's further test was performed to determine the difference in value between treatments. The Duncan test results on the canopy area of the pakcoy mustard are tabulated in table 2, while the difference in plant canopy area in each treatment can be seen visually in figure 3. It can be seen dfrom table 2 that at 5 weeks after planting, the canopy area resulted from the combination of gamelan music gong kebyar and blue-red LED light was not significantly different from the combination of gamelan music gong kebyar and blue-red-white LED light, but significantly different with the combination of gamelan music gong kebyar and white LED light and control. It can be also seen that the combination of Balinese gamelan music gong kebyar and blue-red LED light produced the highest area of plant canopy compared to other treatments. This is in accordance with [4] which stated that the administration of Gong Kebyar gamelan music had a positive effect on the canopy area of pakcoy mustard. According to [26] red and blue lights are good for plant growth in terms of number and width of leaves. But it is not in accordance with the statement of [11] that the application of blue-red-white LED light on lettuce plants produced a higher leaf area than the application of blue-red light. This is presumably because the ratio of the combination of light given is  The combination of gamelan music Gong Kebyar and blue-red LED light increased the growth of the canopy area of pakcoy mustard by 24.2% compared to controls. This is allegedly due to the combination of gamelan music Gong Kebyar and the light blue-red LED accelerate the absorption of light, carbon dioxide and nutrients so that the photosynthesis process takes place more optimally. According to [13] that red and blue light produces more effective waves of light for photosynthesis. This was confirmed by the statement of [10] that red and blue light is the most effective light for photosynthesis because leaves absorb more than 90% of that light. Thus it can be stated that the treatment of the gamelan music gong kebyar and blue-red LED light has a positive effect on the canopy area of the pakcoy mustard.
The combination of gong kebyar music and white LED light showed a significantly different value to other treatments, with the smallest value of plant canopies. The combination of gong kebyar and white LED light shows the inhibition of growth of the canopy area of pakcoy mustard up to 53.4% compared to controls. Pakcoy mustard that treated by a combination of gamelan music Gong Kebyar and white LED light produce a smaller area and number of leaves compared to other treatments, as seen in figure 3. This is presumably because the white light is not optimal for photosynthesis compared to light blue-red and blue-red-white. It can be assumed that photosynthesis will be optimal if plants get the right light so that the process of absorption of light by chlorophyll will be optimal. If combined with the music, it can stimulate the opening of leaf stomata. So, it can be said that the treatment of the combination of gamelan Gong Kebyar and white LED light has a negative effect on the canopy area of the pakcoy mustard.

Effect of Combination of Gamelan Music Gong Kebyar and LED Light on the Greenness of Pakcoy Mustard Leaves
The results of analysis of variance showed that the combination treatment of gong kebyar music and LED light had a significant effect on the greeness of the packcoy leaves. The greeness value of each treatment is presented in figure 4 and the Duncan test results are tabulated in table 3.  The results of Duncan test indicated that the intensity of the green color in the image of the pakcoy mustard shows a significantly different value in each treatment. The combination of gamelan music gong kebyar and blue-red LED light resulted the highest green color intensity which is laso indicated by dark green color of the pakcoy leaves. This is in accordance with the opinion of [21] that the exposure of gamelan music provides the highest leaf green index compared to other treatments. According to [4] gamelan music gong kebyar produces the highest leaf greenness value of packcoy. According to [22] the red and blue LED lights give positive results to the anthocyanin and chlorophyll content of plants. The combination of gamelan music Gong Kebyar and blue-red LED light can increase the greenness of the leaves of the pakcoy mustard plant by 7.8% compared to the control.  Combination of Balinese gamelan music gong kebyar and white LED light produced the lowest greenish leaf value, which indicates a lighter green pakcoy mustard leaf compared to other treatments.  This is presumably because the intensity of the white light used for photosynthesis is not optimal [7] state that several factors influence the synthesis of chlorophyll, namely light, water, temperature, genes and nutrients in the soil. According to [6] the higher the green color of a leaf, the higher the chlorophyll content. So that it can be said that giving a combination of gamelan music gong kebyar and blue-red LED light has a positive result on the greenness of the leaves of the pakcoy mustard. However, the combination of gamelan music gong kebyar and white LED light showed a negative influence on the greenish level of pakcoy mustard leaves.

Effect of Combination of Gamelan Music Gong Kebyar and LED Light on the Roots Length of
Pakcoy Mustard Analysis of variance indicated that the combination treatment of gamelan music gong kebyar and LED light significantly affected the root length of the pakcoy mustard. The difference in root length in each treatment can be visually seen in figure 5, while the Duncan test results on plant root length can be seen in table 3. It can be seen from table 3 that the length of the root of the pakcoy mustard resulted from the combination treatment of the gamelan music Gong Kebyar and the blue-red LED light was not significantly different then the combination of gamelan music Gong Kebyar and blue-red-white LED light. The combination of Balinese gamelan music gong kebyar and blue-red LED light gives the highest average value of root length compared to other treatments. The combination of Gong Kebyar gamelan music and blue-red LED light increase the root length of pakcoy mustard by 26% compared to controls. This is because the canopy growth of pakcoy mustard plants goes well. According to [3] good growth of plant canopy causes photosynthesis to take place optimally so that food reserves can be translocated throughout parts of the body including roots, resulting in good root growth as well. In addition, gamelan gong kebyar music in the pakcoy plant can widen the opening of the stomata thereby accelerating the absorption of water and nutrients by the roots for photosynthesis. Photosynthesis takes place optimally because it is given red and blue light that can be absorbed by more than 90% by plants [10].
The combination of gong kebyar music and white LED light gives a significantly different value to the other treatments with the smallest root length value. The combination of Gong Kebyar gamelan music and white LED light inhibits plant root growth by 5.7% compared to control. This is because the intensity and wavelength of white LED light is smaller than the control, so that the photosynthesis process does not take place optimally, which causes water and nutrients absorbed by the roots are not maximally utilized for photosynthesis. So it can be stated that the the combination of gamelan music Gong Kebyar and white LED light has a negative efect on the root length of the pakcoy mustard. Whereas the combination of gamelan music gong kebyar and blue-red LED light showed a positive effect on root length of the pakcoy mustard.

The Effect of Combination of Gamelan Gong Kebyar and LED Light on Biomass of Pakcoy
Mustard Figure 6 shows the biomass of pakcoy mustard in each treatments, and the results of analysis of variance are tabulated in table 3. The analysis of variance indicated that the combination treatment of gamelan music gong kebyar and LED light significantly affects the biomass of pakcoy mustard.
Note: K = without a combination of gong kebyar and LED light (control) gamelan music, P1 = Combination of gamelan music Gong Kebyar and white LED light, P2 = Combination of gamelan music Gong Kebyar and blue-red LED light, P3 = Combination of gamelan music Gong Kebyar and blue-red-white LED light It can be seen from table 3 that the biomass of pakcoy mustard resulted from combination of gamelan music Gong Kebyar and blue-red LED light significantly different with other treatments. This is consistent with the statement of [21] that the treatment of gamelan music can increase the dry weight of pakcoy mustard plants. The same thing was also conveyed by [4], that Balinese gamelan music gong kebyar can increase the productivity of pakcoy mustard [22] states that red and blue LED light has a positive influence on plant biomass.
The combination of gamelan music gong kebyar and blue-red LED light increase the biomass and pakcoy mustard by 36.1% compared to control. This is presumably because exposure the music to plants can widen the opening of leaf stomata, thus accelerating the entry of carbon dioxide and the rate of absorption of nutrients for photosynthesis which can provide increased photosynthate accumulation [23]. Biomass is the result of net CO2 assimilation during the vegetative growth period of plants [17]. Thus it can be stated that the treatment of combination of gamelan music Gong Kebyar and blue-red LED light can increase the biomass of pakcoy mustard. Thus it can be said that the treatment of the combination of gamelan music gong kebyar and blue-red LED light has positive results on biomass of pakcoy mustard.

Conclusion
Based on the results of the study it can be concluded that 1) combination of gamelan music Gong Kebyar and white LED light has a negative effect on the growth and productivity of pakcoy mustard, while the combination of gamelan music Gong Kebyar and blue-red, and blue-red-white red LEDs light have a positive effect on growth and productivity pakcoy mustard, 2) combination of gamelan music Gong Kebyar and blue-red LED light give the best growth and productivity.