**1. Introduction**

Indonesia is known for its biodiversity of flora and fauna. One species of flora that has a high level of diversity is the orchid plant. The world's orchid species consist of 20,000 species spread over 900 genera. Orchids have a variety of variations that are located in the morphology, such as the shape of the flower, the number of florets, the size and color of the florets, the diversity of leaf and stem shapes (pseudobulb). One of the most orchid species, namely *Dendrobium*, with a total of 1500 species spread very widely throughout the world, from Japan, China, India, the Malacca Peninsula, Indonesia, the island of Papua, to Australia. This orchid has a charming flower and its types are also among the most [1–6].

*Dendrobium* comes from the words "dendro" (tree) and "bios" (life). *Dendrobium* means orchid that grows on a living tree. The advantages of *Dendrobium* because they have a variety of shapes, sizes and colors of flowers. Flowers that have bloomed can last more than 30 days (still in pots) and each stem has more than 20 flower buds arranged neatly and beautifully. When they are adults, *Dendrobium* can remove more than two flower stems at the same time throughout the year. Easy to adapt so easy to maintain. *Dendrobium* growth will be optimal at locations less than 400 meters above sea level. Even so, maintenance in areas over 400 m above sea level can still grow and flower, but not optimum. This orchid has a relatively cheap price. This makes many people tempted to hunt orchids because of high economic value [6].

Lampung is one of the places on the island of Sumatra which has a flora conservation area, which is located in the Liwa Botanical Gardens, West Lampung Regency. The Liwa Botanical Garden has many species of orchids that have not yet been identified, given the high increase in exploitation due to economic reasons, this can threaten the existence of natural orchid plants that cause loss of their natural habitat and natural damage resulting in the extinction of existing flora species, especially on plants orchid. Moreover, orchid plants have high economic value because of the beauty of the various forms of flowers. This makes the reason people can just hunt for existing natural orchids. For this reason, the existence of the Liwa Botanical Garden is expected to guarantee the preservation of natural orchid species that can be utilized sustainably. However, until now there are several types of natural orchids that are not known with certainty what natural orchid species exist in the Liwa Botanical Garden [7–11].

Considering the importance of preserving and preserving orchids in the region, there is a need for further action. One way to do that is by identifying the types of natural orchids, especially *Dendrobium* species which have a high diversity compared to other orchid species. The identification results will be addressed based on leaf morphology and leaf stomata anatomical structure, given the morphological character is one of the approaches that play an important role in the plant's taxonomic and systemic basis. This study aims to determine variations in morphological characters and phenetic relationships and identification of *Dendrobium* based on morphological characters in the Liwa Botanical Garden. The results of this study are expected to be basic information in the identification of natural orchids and conservation efforts in the Liwa Botanical Garden.

#### **2. Identification of stomata morphological characters**

Sample collection was carried out on *Dendrobium* leaves in the Liwa Botanical Garden. Overall, the sample accession is a native orchid of flora from Lampung. All samples were tabulated and documented with photos. The sample collection stage was conducted in December 2019–February 2020 at the orchid green house in the Liwa Botanical Garden. *Dendrobium* samples were chosen based on orchid data that could not yet be identified. Collection results obtained 5 accessions of *Dendrobium* samples with sample codes CAT140, CAT 144, CAT 271, CAT 274, and IR015 (**Table 1**). Overall, the sample accession is a native natural orchid of flora from Lampung.

The morphological identification research phase was carried out by direct observation when sampling in the field. Leaf morphology characters identified included leaf shape, length (P) and width (L) of leaf, leaf tip shape, leaf cross section, leaf arrangement, leaf edge shape, leaf surface texture, leaf symmetry, and leaf sitting [12, 13].

*Identification of Native* Dendrobium *Based on Morphological and Anatomical Characters… DOI: http://dx.doi.org/10.5772/intechopen.102446*


#### **Table 1.**

*List of accessions of* Dendrobium *samples in the Liwa Botanical Garden.*

Based on observations of morphological characters in the field, orchid plants have a high variation. These variations were found in habitus, pseudobulb, leaves, and flowers [13]. In this research the character of the flower is not done because the variation in habitus is seen in plant height, which ranges from 50–125 cm. Plant height can be categorized into 2, namely ≤ 100 cm (short) and> 100 cm (height) (**Figure 1**).

#### **Figure 1.**

*Habitus accession of* Dendrobium *samples in the Liwa Botanical Garden: (A) CAT 274, (B) CAT 144, (C) CAT 140, (D) IR 015, and (E) CAT 271.*

#### **Table 2.** *Leaf type of accession of* Dendrobium *samples in the Liwa Botanical Garden [14].*

*Bar = 1 cm.*

*Identification of Native* Dendrobium *Based on Morphological and Anatomical Characters… DOI: http://dx.doi.org/10.5772/intechopen.102446*

Leaves of *Dendrobium* have most varied organs based on field observation, (**Table 2**). Variation of leaf shape i.e. shape, length (P) and width (L), tip shape, cross section, arrangement, edge shape, surface texture, symmetry, and sitting of leaf [14].

Five accessions of *Dendrobium* from Liwa Botanical Garden showed a different morphological characterization of leaves, i.e. cross-sectional characteristics and sitting of leaf. In the sample with accession number CAT 274, CAT 140, IR 015 and CAT 271 the leaf cross section is zigomorphic (symmetry), whereas on accession number CAT 144 the leaf cross section is tight. In addition, intermittent leaf sitting was found in CAT 274 accession number, IR 215 and CAT 271, in contrast to samples with CAT accession number 144 characters of intermittent leaf sitting and meeting almost filled the plant stem and CAT 140 characters sat leaf intermittent intermittent interspersed and tightly located near the end of the stem [14].

Although the morphological characterization of the leaf shape was the same in all samples, namely the lanceolate/javelin shape, the length and width of the leaves differed from one sample to another. In CAT 274 samples (P: 4.5 cm and L: 1 cm), CAT 144 samples (P: ± 1.7 cm and L: 0.5 cm), CAT 140 samples (P: 9.5 cm and L : 1.5 cm), IR 015 samples (P: 8 cm and L: 2 cm), and CAT 271 samples (P: 8.5 cm and L: 1.5 cm).

Analysis of phenetic was done using cluster analysis and principal component analysis (PCA) methods. The first step is the scoring morphological character using cluster analysis, then calculated the value of Gower similarity (Gower's General Similarity) which results in a matrix of similarity between accessions. Data of matrix similarity using the UPGMA method was done by agglomerative hierarchial clustering, then the result was displayed on dendrogram.

Samples that have a longer leaf length morphological character CAT 140 (P: 9.5 cm and L: 1.5 cm), IR015 (P: 8 cm and L: 2 cm) and CAT 271 (P: 8.5 cm and L: 1.5 cm) will have a higher plant height habitus compared to samples that have shorter leaf morphological characters in CAT 274 samples (P: 4.5 cm and L: 1 cm) and CAT 144 (P : ± 1.7 cm and L: 0.5 cm). Furthermore, there is also a striking difference in the morphological character of the lowest plant leaves, namely in CAT 144 (P: ± 1.7 cm and L: 0.5 cm). Other character differences also have the lowest plant height habitus and have a thicker leaf thickness than the others. The result of morphology character identification of the *Dendrobium* leaves from Liwa Botanical Garden is presented in **Table 3**.

Based on **Table 3**, it is known that most of the accessions of Dendrobium samples in the Liwa Botanical Garden show the same morphological variation in the leaves:

1.The shape of lanceolate/javelin-shaped leaves.


6.Symmetry of leaves in the form of symmetry.

In other characters, namely the form of pseudobulb and the place of growth, it is known that the entire accession of *Dendrobium* samples did not form pseudobulb and



*Identification of Native* Dendrobium *Based on Morphological and Anatomical Characters… DOI: http://dx.doi.org/10.5772/intechopen.102446*

epiphytic antibiotic types. Character types of habitats in general all *Dendrobium* have the same type, epiphytes, according to natural conditions where the sample collection of the Liwa Botanical Garden is a natural orchid taken from its natural habitat, such as the Bukit Barisan Selatan National Park and Seminung Forest which has low humidity (dry) at an altitude of 800–900 m above sea level. Epiphytic orchids grow in their natural habitat requires the intensity of indirect sunlight. In accordance with the type of growth attached to the host [13].

#### **2.1 Phenetic analysis**

Phenetic analysis on five accession of *Dendrobium* is done through cluster analysis and principal component analysis (PCA) methods. The first steps, scoring of the morphological character using cluster analysis, then calculated the Gower similarity value (Gower's General Similarity) between five accessions using matrix of similarities. Then UPGMA methods to calculate the similarity matrix data using clustering of agglomerative hierarchial. The dendrogram results of analysis cluster of five *Dendrobium* accessions based on the morphological characters are presented in **Figure 2**.

Grouping the sample based on the level of similarity between accessions calculated using the gower coefficient formula and UPGMA was chosen for the clustering technique to produce a dendogram showing 2 main groups formed with a similarity index value of 0.813 marked as group A and group B. Group A consists of CAT 144 which has a distinguishing character that distinguishes from group B, namely the cross section of the double leaf character (Figure CAT 144). Group B consists of CAT 140, CAT 271, IR 015, and CAT 274 which have symmetrical cross-section characters (Figure CAT 140, CAT 271, IR 015, and CAT 274). Group B is divided into 2 sub-groups with a similarity index value of 0.861 marked with B1 and B2 on the dendogram. Characters that show the difference between the two, namely the ratio of the length and width of the leaf and leaf sitting. CAT 140 consists to subgroup B1, meanwhile CAT 271, IR 015, and CAT 274 consist to subgroup B2. Subgroups B2 are divided into 2 based on differences in leaf length and width ratios namely B2a and B2b. IR 015 and CAT 274

**Figure 2.**

*Dendrogram five* Dendrobium *accession of samples from Liwa Botanical Garden using UPGMA.*

in one group B2b with a similarity level of 100% were indicates the same type. Based on the PCA values, it can be seen that characters have a large influence on grouping are the ratio of length and width (PLD), cross section (PMD), and sitting (DKD). Variability of orchid leaf characters can be possible due to the hybridization and outcrossing processes.
