Creation of ten new variety of Begonia through interspecific Hybridization: A Study from Bali Botanic Garden’s Collection

Begonia is one of the plant genera and very popular as an ornamental plant. Bali Botanic Garden has collected and conserved at least 90 species and 241 exotic Begonia. As an ornamental plant, Begonia has unique, special and beautiful characteristic in its leaf, flower and plant features. Interspecific hybridization is commonly used to improve the morphological character of Begonia. The purpose of this study is to define new variety of Begonia from the interspecific hybridization of Bali Botanic Garden Begonia’s collection. From 2014 until 2022, ten new varieties of Begonia obtained from several species: B. acetosa, B. caravan, B. cuculata white, B. fenicis, B. fimbriata red, B. goegoensis, B. incarnate, B. listada, B. longifolia, B. semperflorens, B. silver queen, B. sizemorae, B. sudjanae, B. tuberosa and B. variepeltata. The new variety are: Begonia “Tuti Siregar”, Begonia “Longisilver”, Begonia “Longigreen”, Begonia “Sizequeen”, Begonia “Bedugul”, Begonia “Eka Karya”, Begonia “Vena Red”, Begonia “Ardaka”, Begonia “Lugrayasa” and Begonia “SuGo”. Out of the ten new varieties, eight varieties have been registered with the Center of Plant Variety Protection and two have already granted Plant Protection Variety Right.


1.
Introduction Begonia is one of the largest flowering plant genera with 2117 accepted species [1].These numbers still count with numerous publications on new species of Begonia [2 -6].Well known as an ornamental plant, Begonia has unique and beautiful characteristic on its leaf, flower and plant features.Begonia easily recognized with asymmetrical leaves, colorful foliage, thick and succulent stem, large showy flowers and the presence of unisexual flowers featuring petal-like perianth segments.
Bali Botanic Garden as an institution of ex situ conservation, has collected at least 90 species and 241 exotic Begonia.The native species were obtained during plant expedition from their natural habitat.The Bali Botanic Garden possess an extensively comprehensive living collection of Begonia [7].This collection represents a valuable resource for breeding purposes.Hybridization is a mechanism to assembling genetic diversity and produce new varieties possessing superior traits i.e.: longer flowering time, the shape and new color of foliage, and resistance to pest and plant diseases [8 -9].In Begonia, hybridization has been used extensively to improve its morphological character i.e.: flowers, leaves and stem.
In the period from 2014 to 2022, ten new varieties of Begonia have already been created through interspecific hybridization from Begonia collection in Bali Botanic Garden.The result of this crossing is expected to have a prospect as a commercial ornamental plant.Thus the objective of the research presented in this paper is to identify improved morphological characteristics of the new varieties of Begonia.

Material and methods
The research was conducted at Begonia Greenhouse of Bali Botanic Garden, at an altitude 1200-1450 m asl daily temperature 18-20 o C and relative humidity 70-90%.The parental plants for hybridization were selected from the Bali Botanic Garden collection based on the following criteria: healthy growth and producing male or female fertile flowers.
The interspecific hybridization research between selected species, conducted when the female flower was ready to receive pollen.At the time of anthesis, fresh pollen from the male flower was obtained and transferred to the stigma of the recipient flower.After pollination, the fruit will be formed and harvested.The seed were planted and observed for their germination and growth into individual seedling.The individual selection was two seasons selected.F1 individual selection was selected based on its morphological features with novel and unique character.Characteristics of the clones were observed by vegetative (plant morphology, leaf length, leaf width, leaf shape, stipule, leaf tip, leaf base, etc.) and generative characteristics (inflorescence, flower type, flower color, etc.).Royal Horticultural Society (RHS) Color Chart was used to determination of color.Selected F1 plant of these mass selection resulting clone and propagated by vegetative through leaf cuttings.
x Figure 1.Variety assembly chart

3.
Result and discussion As described below, the hybridization process and morphological character of ten new varieties of Begonia in Bali Botanic Garden: (The summary is provided in table 1).

Begonia "Tuti Siregar"
Begonia "Tuti Siregar" is crossing from B. listada as female parental and B. acetosa as male parental.After pollination, the fruit is set and ripened 30-45 days after fertilization.The seed then planted and germinated 11-40 days after sown.Germinated seed then grown as seedling and observed for F1 mass selection.Begonia "Tuti Siregar" features are erect stem, leaf type single, leaf shape ovate, leaf tip acute, upper leaf color green, inflorescence moderate, flower type single.Male flower color white, with 4 tepals.Female flower color white, with 4 tepals.Unique morphological character of Begonia "Tuti Siregar" (figure 2 (1)) are beautiful leaves intermediate of both parents, deeply red petiole covered with wooly hairs and yellow vein leaf [10].This new variety granted Plant Protection Variety Right on the Center for Plant Variety Protection and Licensing Agriculture (PPVTPP), the Ministry of Agriculture by No. 00275/PPVT/S/2014.Tuti Siregar name, derived from the breeder who crossed the Begonia.

Begonia "Longisilver"
Begonia "Longisilver" is registered on the Center of Plant Variety Protection (PPVTPP) by No.

Begonia "Longigreen"
Begonia "Longigreen" is a primary hybrid produced at the Bali Botanic Garden, completed in 2013 and developed through crossbreeding between the Begonia "Silver Queen" collection plant (TT 42) as the female parent and B. longifolia (TT4) as the male parent.After pollination, the fruit is set and ripened 135 days after fertilization.This variety features are erect stem, stem color red-greenish.Plant height average 70,33 cm and canopy width average 47,67 cm.Leaf type single, leaf shape ellips, leaf tip acuminate, upper leaf color Green N 137 A, bottom leaf color Greyed Purple 187 A. Flower type single, female flower color white, with 6 tepals.Male flower color white.The characteristics that distinguish this hybrid from its parent plants include an elliptical leaf shape, shallow leaf notches, Green 137 A coloration on the upper leaf surface, Greyed Purple 187 A on the bottom leaf surface, single flowers White 155 D (figure. 2 (4)).Begonia "Longigreen" has been registered and certified as a new plant variety under the registration number 377/PVHP/2016 from the Center for Plant Variety Protection and Licensing Agriculture (PPVTPP), the Ministry of Agriculture.

Begonia "Sizequen"
Begonia "Sizequen" is resulted from female parent B. sizemorae and male parent Begonia "Silver Queen".After pollination, the fruit is set and ripened 36 days after fertilization.Begonia "Sizequen" has an erect stem, tomentulose and stem color brown reddish.Leaf type single, leaf shape ovate, leaf tip acuminate, upper leaf color dark green.Bottom leaf color red maroon.Flower type single, female flower color pink with 6 tepals.Male flower color pink with 4 tepals.The attractive characteristics of Begonia "Sizequen" (figure.2(5)) are leaf shape ovate, leaf base cordate, leaf edge serrulate, upper leaf dark green and bottom leaf red maroon.This variety has been registered and certified by the Center for Plant Variety Protection and Licensing Agriculture (PPVTPP), the Ministry of Agriculture with the registration number 349/PVHP/2015.

Begonia "Bedugul" Crossing between B. semperflorens as parental female and B. cucullata as parental male resulted
Begonia "Bedugul".Bedugul is the name of Bali Botanic Garden located.After pollination, the fruit is set and ripened 42 days after fertilization.The fruit harvested and the seed planted for germination.The seed germinated 72 days after sown.The seedling observed for F1 mass selection.The variety has erect stem, stem color red purplish with plant height 50-70 cm.Leaf type single, leaf shape ellips, leaf tip acuminate.Upper leaf color Green N 137 A, and bottom leaf color Greyed Purple 187 A).Flower type single, female flower color pink with 7 tepals.Male flower color pink with 4 tepals.The difference morphological character of Begonia "Bedugul" from both parental are it has longer petiole and pink whitish flower (figure.2(3)).Begonia "Bedugul" has been registered by the Center for Plant Variety Protection and Licensing Agriculture (PPVTPP), the Ministry of Agriculture with the registration number 638/PVHP/2018.

Begonia "Eka Karya"
Begonia "Eka Karya" is resulted from B. tuberosa as female parental and B. fimbriata red as male parental.The fruit set and ripened 66 days after pollination.Begonia "Eka Karya" has erect stem, a stem color red greenish and plant height 70 cm.Leaf type single, leaf shape ellips, upper leaf color Green N 137 A and bottom leaf color Greyed Purple 187 A. Flower type single, female flower color white with 6 tepals, male flower color orange with 6 tepals.This new variety (figure. 2 (7)) has different morphological characters with both parental.Upper leaf Green 137 A with secondary Greyed Purple N 187, male flower orange group (29 C).Eka Karya derived from Bali Botanic Garden name, Kebun Raya "Eka Karya" Bali.This variety has been registered and certified by the Center for Plant Variety Protection and Licensing Agriculture (PPVTPP), the Ministry of Agriculture with the registration number 00542/PPVT/S/2020.

3.7.
Begonia "Vena Red" Crossing between B. varipeltata as female parental and B. fenicis as male parental resulted Begonia "Vena Red".After pollination, the fruit is set and ripened 69 days after fertilization.The fruit harvested and seed planted for germination.The seed germinated 24 days after sown.The seedling grown and observed for F1 mass selection.This variety has erect stem, glabrous and stem color red purplish with lighted spot.Leaf type single, leaf shape ovate, leaf tip acuminate.Upper leaf has three color, basic color Greyish Olive Green NN 137 A, secondary color strong Yellowish Green NN 144 A and tertiary color Moderate Red N 34 A. Bottom leaf has two color, primary color reddish green and secondary color red.Begonia "Ardaka" Artificial crossbreeding was conducted using the female parent B. varipeltata and the male parent B. fenicis.The fruit is set and ripened 68 days after fertilization.The seed planted and germinated 21 days after sowing.Begonia "Ardaka" has erect stem, stem color red purplish with lighted spot, plant height 25 cm.Leaf type single, leaf shape ovate, leaf tip acuminate.Upper leaf color Dark Green 135 A, bottom leaf color light green.Flower type single, female flower color Very Pale Purple 75 D with 5 tepals.Male flower color Very Pale Purple 75 D with 4 tepals.The primary differences in character between the offspring and their parent are observed in the coloration of the stem.The stem displays a deep reddish-purple coloration with scattered, sparse bright spots.Leaf stalk, petiole is short (+13 cm) and red in color, with a glabrous surface and a lanceolate stipule and leaf (figure.2( 8)).The derivation of the name originates from the name of the Begonia researcher at Bali Botanic Gardens -BRIN, I Made Ardaka.He has successfully conserved numerous species of natural Begonia, collected hybrid Begonias, and produced several hybrid Begonia species in the Bali Botanic Gardens-BRIN.Begonia "Ardaka" is registered on the Center for Plant Variety Protection and Licensing Agriculture (PPVTPP), the Ministry of Agriculture by No. 720/PVHP/2019.

Begonia "Lugrayasa"
Begonia "Lugrayasa" is a hybrid resulting from the crossbreeding of the female parent Begonia "Caravan" with the male parent B. incarnata.The fruit is set and ripened 39 days after fertilization.The variety has erect stem, glabrous, stem color red purplish with lighted spot, plant height >75 cm.Leaf type single, leaf shape obtrullate, leaf tip acuminate.Upper leaf color Moderate Olive Green 147 A and bottom leaf color Dark Red 183 B. Flower type single, female flower color Pale Yellow Green 155 A with 5 tepals.Male flower color Pale Yellow Green 155 A with 4 tepals.The main differences in characters between the offspring and their parent are as follows: reddish coloration on the lower surface of leaves, dark green coloration on the upper surface of leaves, longer length of both male and female flower stalks, and larger and whiter corolla size (figure 2(9)).The derivation of the name originates from I Nyoman Lugrayasa (the former Head of Bali Botanic Gardens as well as the name of the Begonia Breeder Researcher).Begonia "Lugrayasa" is registered on the Center for Plant Variety Protection and Licensing Agriculture (PPVTPP), the Ministry of Agriculture by No. 849/PVHP/2020.

Begonia "SuGo"
Begonia "SuGo" resulted from crossing of B. sudjanae and B. goegoensis.After pollination, the fruit ripening 49 days after fertilization.The seed planted and germinated 30 days after sown.Begonia "SuGo" has rhizomatous stem, plant height 20,5 cm.Leaf type single, leaf shape rotundum, leaf tip acuminate.Flower type single, female flower color white with 4 tepals.Male flower color white with 4 tepals.The attractive character of Begonia "SuGo" are upper leaf Yellowish Green 174 A with secondary color Greyed Purple 187 A, flower white (figure. 2 (10)).This variety is registered on the Center for Plant Variety Protection and Licensing Agriculture (PPVTPP), the Ministry of Agriculture by number 849/PVHP/2020.
Interspecific hybridization is the crossing of two species of the same genera.This method commonly used in breeding of ornamental plants to produce new varieties or cultivars with improved traits [11].As ornamental plants, most commercially grown are Begonia hybrids [12].Begonia collection in Bali Botanic Garden provided parental stock as genetic resources for creating Begonia hybrids with superior character and also enhanced their genetic diversity.These potential resources need to be developed with other method i.e.: mutation by chemical or physical treatment, that more new varieties created and increased the economic value.

Conclusion
Ten new varieties of Begonia resulted from the interspecific hybridization of 15 Begonia

Fruit
harvesting and seed sowing Seed germination, seedling growth and selection F1 individual selection and vegetative propagation ♂ Begonia Bali Botanic Garden Plant Collection ♀ Begonia Bali Botanic Garden Plant Collection Selected Clone as New Varieties of Begonia 387/PVHP/2016.This new variety is resulted from parental female Begonia "Silver Queen" (TT 42) and male parent B. longifolia (TT 4).The fruit is set and ripened 135 days after fertilization.The seed was sown and observed for germination and seedling growth.Begonia "Longisilver" character, are erect stem, with reddish violet stem, stem height 50-70 cm.Leaf type single, leaf shape ellips, leaf tip acuminate, upper leaf color Green N 137 A, bottom leaf color Greyed Purple 187 A. Flower type single, male flower color pink with 4 tepals.Female flower color pink with 7 tepals.The different characteristic from its parent, are elliptical leaf shape, shallow leaf notches, upper leaf Green 137 B with secondary color Reddish Purple 70 B, single flowers color White 155 D (Fig 2 (2)).Begonia "Longisilver" has been registered on the Center for Plant Variety Protection and Licensing Agriculture (PPVTPP), the Ministry of Agriculture by number 387/PVHP/2016.

4
Flower type single, female flower color Very Pale Purple 73 D with 5 tepals.Male flower color Very Pale Purple 73 D with 4 tepals.The attractive character of Begonia "Vena Red" (figure.2(6)) are: stem reddish purple with bright spot, upper leaf Greyish Olive Green NN 137 A with Strong Yellowish Green NN 144 in the middle and Moderate Red N 34 A in the edge.Begonia "Vena Red" is registered on the Center for Plant Variety Protection and Licensing Agriculture (PPVTPP), the Ministry of Agriculture by No. 721/PVHP/2019.1255 (2023) 012029 IOP Publishing doi:10.1088/1755-1315/1255/1/0120295 3.8.