Morphological characters and yields of five Vanilla (Vanilla planifolia Andrews) clones in Bali

Indonesia is one of the countries with the largest vanilla production in the world. Vanilla has been cultivated in several regions of Indonesia, especially those that have at least three months of the dry season. One of the areas that have these criteria is Bali. This study aimed to determine five vanilla clones’ morphological characteristics and yield. The research was conducted in Jembrana district-Bali. A total of five vanilla clones were tested using a randomized block design with six replications. Vanilla clones were grown in a plot size of 13.25 x 8 m2 at 1.5 m x 1.25 m in a row. Morphological characters observed were leaves, fruits, roots, and yields. The results showed that leaf length was 16.97 cm - 18.52 cm, leaf width was 6.52 cm - 7, 11 cm, leaf thickness was 2.1 - 2.3, internode length 12.50 cm- 16.68 cm, vine diameter was 1.18 cm- 1.35 cm, number of bunches/trees 2, 70 - 6.15, number of flowers/bunch 14.55 - 20.30, number of fruits/bunches 12, fruit length was 15.69 cm- 19.35 cm, fruit diameter was 1.24 cm - 1.36 cm, fruit weight was 16.11 gr - 19.20 gr, and wet beans/plant production about 0.6 kg - 1.96 kg. The radix adligans of the five vanilla clones showed no significant difference with root lengths was 6.45 cm – 6.89 cm. Clone number 4 was adaptive and high yield in Bali.


Introduction
Vanilla (Vanilla planifolia Andrews) is a genus of the Orchidaceae family known for its aromatic pods that produce vanilla flavoring.The genus Vanilla is known to reach 140 species, then more in-depth results about this genus were confirmed to 118 species in the Orchidaceae family [1].The plant is a vine that can grow up to 30 meters long and has thick, fleshy leaves and greenish-yellow flowers.The vanilla plant is a climbing orchid that requires support from trees or poles, and it takes several years for the plant to begin producing vanilla beans.
The vanilla plant is native to Mexico and Central America but is now widely cultivated in tropical regions worldwide.Vanilla species have a naturally occurring pantropic distribution in the tropics of the New World, from South Florida and Mexico, Central America and the Antilles to South America; in tropical Africa, both mainland and Madagascar; in tropical Asia, from China and India to New Guinea and Southeast Asia [2].In addition, vanilla plants thrived in new regions that comprise today's major vanilla-growing areas, including Madagascar, Indonesia, Uganda, India, and others [3].
Indonesia is one of the world's largest producers of Vanilla, along with Madagascar and other countries in the region.Madagascar dominates vanilla production with Indonesia, Uganda, India, Comoros, and Mexico contributing significantly to global supply and minor production in many other countries [4].Indonesia's exports are primarily cured vanilla beans, although some processed vanilla products, such as vanilla extract, are also exported.Madagascar's market share as the world's primary vanilla producer and exporter reaches 57%, while Indonesia only has 6.7%, and the price is only 50% of Vanilla from Madagascar [5].
In Indonesia, most vanilla production occurs on Java Island, particularly in the Central and East Java provinces.Another area in Indonesia that is a production center is Bali, where Bali has the potential to meet the world's supply of Vanilla [6].In addition, the three main areas for vanilla cultivation in Bali are Tabanan Regency, Jembrana Regency, and Buleleng Regency [7].Jembrana Regency is located at 8°03ʹ40ʺ-8°50ʹ48ʺS and 114°25ʹ53ʺ-114°42ʹ40ʺE, which covers 841.8 km2 or 14.93% of Bali.Besides that, the Jembrana district has rainy and dry seasons, in which heavy rains occur from December to March; the dry season usually begins in April or May (three months or more) [8].
Plant characterization is a process of identifying and describing the physical and biological characteristics of a plant species.Characterization can include plant morphology, anatomy, physiology, and genetic information.In addition, plant identification and description activities to obtain information on the benefits of special traits of germplasm resources, recognize diverse individual taxonomic features and insert them into taxa [9].Morphological characteristics include features such as the plant's height, the size of leaves, the shape of flowers, and the color of the fruit.Furthermore, morphological characteristics (i.e., leaves, stems, branches and flowers, etc.), especially their form, size, and variability, are the primary source of genetic diversity [10].Plant characterization is essential for various purposes, including plant breeding, taxonomy, and conservation.By understanding the characteristics of different plant species, scientists can develop new varieties with improved traits, identify and classify other species, and develop strategies for protecting endangered plant species.This study aims to determine five vanilla clones' morphological characteristics and yield in Bali for creating a new variety.

Plant material
The material used in this study is five clones aged three years produced from the individual selection from the germplasm of the Indonesian Spice and Medicinal Research Institute.The research was conducted at Jembrana District, Bali, Indonesia (650 m asl) with C3 climate type (Oldeman climate) and andosol soil type, black clay.

Experimental design
The environmental design was a randomized block design with six replications.For each treatment (clone), there were 20 plants.The enforcer tree used is Glyricidia maculata (Gamal) which was planted 6-9 months before planting Vanilla with a height of ± 1.50 m.The planting distance is 1.50 x 1.25 m.The plot size is 13.25 X 8 m2, and the number of plants per plot is 100.Fertilizing using manure 20 kg/plant given at the beginning and end of the rainy season (2 times).Inorganic fertilization is given depending on the age of the plant, namely (1) for vanilla plants aged 1-2 years (20 g of Urea + 35 g SP-36 + 45 g KCl), (2) for plants over two years (40 g of Urea + 75 g SP-36 + 90 g KCl).

Observation of morphological traits
A total of eleven phenotypic traits (growth and yields) were used for morphological characters.Observation parameters are made to the visual appearance of the plant, and the growth parameters include tendril; rod diameter; node length, leaf length; leaf width; leaf thickness; root length; and root adhesion.Flower and fruit observations have the number of bunches/plants, the number of flowers/bunches, the number of fruits/bunches, the length of the fruit (bean), and the diameter of the fruit.The yield components were also observed, such as fruit weight, production/plant, and production of beans (wet and dry pod).Observations of the morphological characters referred to plant morphology [11] and the International Union for The Protection of New Varieties of Plants Guidelines for The Conduct of Tests for Distinctness, Uniformity, and Stability [12].

Characters of plant
The plant character of the plant tendrils showed that the tendril length of Clone 4 and Clone 1 was longer than the other clones, reaching 6.5 and 6 turns, respectively, while the lowest tendril length was 4 turns, namely Clone 5.In addition, Clone 2 and Clone 3 have tendril lengths of around 5 -5.5 turns (table 1).Tendrils are touch-sensitive threadlike organs used exclusively for climbing [13].The tendrils of vanilla plants can grow up to several meters long.These tendrils help the vanilla plant to anchor itself and reach toward sunlight.The tendrils must be attached to the enforcer tree with a height of 1.75 meters, then the tendrils hung and rotated so that crossing and harvesting make it easier for farmers.The rod diameter of Vanilla did not show a significant difference between clones.The largest rod diameter of Clone 4 is around 1.35 cm, while the smallest rod diameter is Clone 5, around 1.18 cm.
Turning to other characters, the character node length of Clone 4 has longest than other clones, around 16.68 cm, whereas Clone 3 has a node length approaching Clone 4 was around 15.39 cm.Clone 2, Clone 1, and Clone 5 have short of nodes, approximately 13.52 cm, 12.79 cm, and 12.50 cm, respectively.The nodes of a vanilla plant are vital because they are the points at which the plant climbs and grows along a trellis or other support structure.Based on observations of the leaf characters, Clone 4 has a leaf length (of 18.35 cm), a leaf width (of 7.11 cm), and a leaf thickness (of 2.33 cm), which is a larger size than the others, even though the leaf length is no longer than the Clone 1.In addition, the size of leaf Clone 1 is nearest to Clone 4, with a leaf length of 18.52 cm, a leaf width of 7.09 cm, and a leaf thickness of 2.25 cm.Other clones (2, 4, and 5) are insignificant in leaf characters.The root length did not differ between the 5 vanilla clones, around 6, and the radix adligans of the 5 vanilla clones had strong adhesion.

Characters of fruit and yield
Vanilla fruit is an indicator of plant generative development.The yield of Vanilla can vary depending on various factors, including soil quality, climate, and growing conditions.The flowering of vanilla beans usually occurs three years after planting and takes about eight to nine months from flowering to harvest.Based on observations (table 2), the number of Clone 4 flowers reached 20 flowers/bunches and the number of bunches was around 6 bunches/plant, the largest of all clones (Picture 1).In contrast, clones 2 and 5 had a small number of flowers around 14, but bunches of Clone 2 were higher than Clone 5. Clone 1 had a lower number of flowers was 15 and bunches was 13, while the number of flowers and bunches of Clone 3 was 19.35 and 5.60, close to Clone 4. The parameters number of flowers and the number of bunches is strongly influenced by climate.If the air condition is too dry it will reduce the number of flowers that will form, which will cause a decrease in yield; otherwise, low temperatures will stimulate vanilla flowering [14].

Figure 1. Number of bunches per plant Vanilla clones in Bali
There is no difference in the number of fruits between the five clones was 12.There was no difference in the length of the vanilla pods in Clone 4, Clone 2, and Clone 1 with values of 19.35 cm, 19.17 cm, and 19.03 cm, respectively, while the shortest fruit length, namely Clone 5, was around 15.69 cm and Clone 3 was close to the fruit length of the three clones above.The fruit diameter data of five clones have the same value of about 1 cm.Interesting data occur in the yield components (table 3).Clone 1 had the highest fruit weight of around 19.20 g, while Clone 2, Clone 3, and Clone 4 had medium fruit weights of approximately 17.59 g, 17.16 g, and 18.85 g, where Clone 4 was close to the highest weight.Clone 5 had the lowest fruit weight was 16.11 g.If the weight of vanilla more than 15 grams, the aroma will be appeared.The vanilla bean weighing more than 15 grams had a sweeter scent than the other sizes, albeit the difference was not statistically significant [15].The production of Clone 4 vanilla pods was around 0.58 kg/plant with a wet pod weight of 10523 kg/ha and a dry pod of 2239 kg/ha.Clone 2 and Clone 3 had the same production per plant of 0.50 kg, but the wet and dry pod weights differed.The wet pod weight of Clone 2 was around 9768 kg/ha and the dry pod was 1918 kg/ha, while Clone 3 had a wet pod weight of 10392 kg/ha and a dry pod of 2165 kg/ha.Clone 1 had production was 0.45 kg/plant with wet pods of 9768 kg/ha and dry pods of 2035 kg/ha.Clone 5 had the smallest plant production with a value of 0.12 kg/plant and 9676 kg/ha wet pods and 1872 kg/ha dry pods.

Table 1 .
The average vegetative growth of five Vanilla clones in Bali

Table 2 .
The average generative growth of five vanilla clones in Bali

Table 3 .
The average data of yields the observation of five vanilla clones in Bali Clone 4 is the best vanilla clone of the five clones studied.Besides that, this clone can adapt well in Bali.Clone 4 has superior characters in tendril (6.5 turns), rod diameter (1.35 cm), node (16.68), leaf length (18.35 cm), leaf width (7.11 cm), and leaf thickness (of33 cm).In addition, the production of Clone 4 vanilla pods was around 0.58 kg/plant with a wet pod weight of 10523 kg/ha and a dry pod of 2239 kg/ha.However, Clone 4 was lower than Clone 1 around 18.85 g in the fruit weight parameter.There were no differences in root parameters and the number of fruits per bunch in the five clones.Clone 5 is the lowest clone of all parameters observed.