Growth diversity, heritability, and genetic correlation of 2-year-old of manglid (Manglietia glauca Bl.) progeny test in Candiroto, Temanggung, Central Java

Manglid, an Indonesian flora, is highly sought after due to its high public interest in planting it. It is necessary to develop superior seed sources to increase the plant’s productivity. This study aimed to determine variations in plant growth, heritability, and genetic correlation of Manglid plants in a 2-year-old progeny test in Candiroto. A Randomized Completely Block Design with two components population and family used in this study. Families are nested within the population. There are 3 populations and 100 families; 15 of the 100 families were from Tasikmalaya, 10 were from Sumedang, and 75 were from Sukabumi. Plant height and stem diameter were measured. The analysis revealed a significant relationship between population, family, and family within the population and plant height and stem diameter development. Sumedang populations had the best height and diameter at 4.19 meters and 6.15 centimeters, with 27 differences in height growth and 24 variances in diameter growth at the family level. The estimated individual heritability for height was 0.21, while for stem diameter it was 0.17. The family heritability for height and stem diameter was 0.52 and 0.49, respectively. A 0.83 genetic correlation was found between height and diameter.


Introduction
Forestry and Other Land Use (FOLU) net sink 2030 can be achieved through 11 operational steps to mitigate the FOLU sector.One of the operational steps is the Development of Plantation Forests [1].Within the construction of plantation forests, productivity improvement is needed.The variety of plant growth diversity is an important factor in productivity improvement.When the existing diversity is relatively high, there will be possibilities in choosing the plants that have the best growth criteria as expected.Indonesia is a country that has very high biodiversity.One of the native Indonesian flora whose existence is rarely found is Manglid (Manglietia glauca) [2].Manglid is naturally found on Sumatra Island, Java Island, Bali Island, Lombok Island, and Sulawesi Island at an altitude of 900 to 1700 m above sea level in moist mixed forests and fertile soil [2].Its natural habitat in Sukabumi, precisely in Situ Gunung, Manglid has an abundance value of 1.2, meaning it is a rare class [3].
Manglid wood is included in the third strong and second durable classes with shiny wood properties, dense structure, smooth, light, and easy to work on [4] [5].Manglid is a fast-growing tree species with an under ten-year cycle [6].These wood properties attract the community to plant Manglid in community forests to fulfil the wood needs, especially in East Priangan, West Java [7].Manglid wood can be used to make bridges, household utensils, tables, chairs, cabinets, house buildings, door leaf materials, wood coatings, and plywood [7].
Due to public interest in planting Manglid being quite high, while its abundance in nature is rare, it is necessary to develop superior seed sources to increase the plant's productivity.Superior seed sources can be obtained through the construction of offspring test plots.Apart from that, Manglid is one type of plant that must be cultivated using certified superior seeds [8].
Gaining superiority in plant productivity requires information on growth variations, genetic traits, and correlations of growth traits inherited by offspring.This study aimed to determine plant height growth and stem diameter diversity, heritability, and genetic correlation of Manglid plants cultivated as seed sources in Candiroto, Temanggung, Central Java.

Material
A Seedling Seed Orchard of Manglid aged two years in Candiroto Temanggung, Central Java, was used in this study.The seeds come from Tasikmalaya, Sumedang, and Sukabumi, West Java [9].The plant growth measurements are carried out at the age of 2 years.The research location is 7° 06.687 S and 111° 06.267 E, with an altitude of 457-464 m above sea level and latosol soil type [10].The tools used are height measuring poles, phybands to measure diameters, tally sheets, seedling seed orchard map design, field notes, and stationeries.= the influence of the k-th family nested in the j-th population; Bi*Fi(Pj)= the effect of the interation of the i-th block with the k-th family nested in the j-th population; Eijkl = random error.
Individual and family heritability on tree height and stem diameter characters were estimated using the following equation.The variance component of the family (σ 2 f) in the individual heritability equation is assumed to be 1/3 of the additive genetic variance (σ 2 A) because the potential for single of relative mating of Manglid plants in nature is quite high [12] [13].The estimated genetic correlation between traits was calculated using the following formula [14]   =  () √ ()

Growth diversity
The measurement results of plant height and stem diameter of 2-year-old Manglid progeny test plants in Temanggung, Central Java, showed a diversity.The calculation results showed that the average plant 4 height was 3.97±1.04meters, and the stem diameter was 5.96±2.19centimeter.A variant analysis was carried out, as presented in Table 2 to determine the diversity of growth of the observed characters.Analysis of variance showed that population origin, kinship, and family within the population in the ancestry test of the 2-year-old Manglid in Temanggung, Central Java, had a very significant effect (Table 2.).A significant effect of family on height and stem diameter growth also occurred in the progeny test of Manglid aged 4 months in Trenggalek, East Java [15].External and internal factors influence noticeable differences in height and stem diameter growth.The external factors are environmental factors, where in this study, the division of blocks shows a significant difference between blocks (Table 2.), while the internal factor is from the genetic family itself [16].
The average plant measurement result of Tasikmalaya, Sumedang, and Sukabumi populations were 4.04 meter, 4.19 meter, and 3.92 meter.The average stem diameter were 5.91 centimeter, 6.15 centimeter, 5.94 centimeter.To determine the differences between treatments, DMRT tests were carried out on the diversity of growth, height, and stem diameter between populations, presented in figure 1. DMRT test results of population influence on height character and stem diameter showed a significant difference caused by differences in 3 groups for height traits and 2 groups for stem diameter properties.
The high genetic diversity in this type of Manglid can be caused by interbreeding, pollination that occurs with the help of insects, spreading area, long life cycle, and occurrence during the succession stage and before the treatment by humans [17].Moreover, large populations with geographical locations separated by mountains, rivers, lakes, and grasslands can also cause genetic diversity in populations [18].Several studies on other tropical wood species also show a large genetic diversity in the population, such as ulin (Eusideroxylon zwageri) [19], Merbau (Intsia bijuga) [20]; [21], sandalwood (Santalum album) [22], agarwood (Gyrinops verstigii) [23] and Aren (Arenga Pinnata) [24].
The analysis of variance results showed that the family had a very significant effect.Therefore, it is continued with the DMRT test.DMRT test results show 27 variations in plant height growth differences (appendix 1) and 24 variations in stem diameter growth differences (appendix 2).
The plant measurements showed a plant height of 3.09 meter -4.79 meter and a stem diameter of 4.50 centimeter -8.57centimeter.The variations in the growth traits of the height and stem diameter of several families are suspected to be caused by differences in the conditions in which each parent tree grows.As revealed by [17], their genetic traits influence the diversity of tree traits among individual trees.
The existence of genetic diversity provides an opportunity to choose the best family to develop.The selection of the best-developed family can increase the productivity of plant growth.

Heritability
The estimated value of heritability ranges from 0 -1.If environmental factors influence the variation that occurs in a plant, the estimated heritability is 0. On the other hand, if genetic factors influence the variation in an individual plant, the estimated heritability value is 1.According to [25], the individual heritability value (hi 2 ) below 0.1 means low; 0.1-0.3means medium/moderate; more than 0.3 means high.Familial heritability (hf 2 ) below 0.40 is low; 0.40-0.60 is categorized as medium/moderate; 0.60-1 is high.High and moderate heritability values indicate that genetic factors strongly influence growth trait variation.Information regarding heritability will aid the selection process in tree breeding [26].
The estimated heritability value for the height and stem diameter of the 2-year-old Manglid progeny test plot is presented in table 3. The estimated heritability values showed that the individual heritability values for plant height and stem diameter characters were 0.21 and 0.17, respectively, and then family heritability values for height and stem diameter characters were 0.52 and 0.49, respectively (Table 3.).According to [25], the individual heritability of the character's height and stem diameter belongs to moderate criteria.Likewise, the heritability value of the character family, the height and diameter of the rod include moderate criteria.These moderate criteria indicate that the genetic diversity of Manglid is relatively high.The same research results also occurred in Alstonia angustiloba aged 3 years [27], Alstonia angustiloba aged 4 years [28], Gmelina arborea aged 1 and 2 years [29], Pinus merkusii aged 2 years [30] .

Genetic correlation
Genetic correlation is a correlation between breeding values for different traits, mainly caused by genes that affect more than one trait (pleiotrophy) [31].In tree breeding science, the genetic correlation between characters is used to implement selection efficiently.If the correlation is positive, strong, and consistent until the age of the plant is ready to be selected, then the selection can be effective and efficient because selection activities require one character only.The calculation results of the genetic correlation between plant height characters and stem diameter in the 2-year-old Manglid progeny test can be seen in table 3.

6
Table 3 shows that the genetic correlation of 0.83 is positive.According to [32], the positive genetic correlation will make determining the selected characters easier.The value of the genetic correlation between plant height and stem diameter is strongly positive at 0.83.This high genetic correlation value indicates that an increase in plant height will be followed by stem diameter or vice versa.This illustrates a positive linear relationship between the increase in height and the stem diameter.The positively correlated height and stem diameter show that the character can be bred simultaneously.That is, the improvement of one character will improve another.The same study's results were shown in Aquilaria malaccensis aged 4 years [33].

Conclusion
There are variations in plant height growth and stem diameter.The population has a very significant effect on the growth of the height and stem diameter.In addition, the family in the population significantly affects the growth of the height and stem diameter.The prediction of the individual heritability values for plant height traits and stem diameter is categorized as the moderate criterion.Moreover, in the family, heritability for plant height traits and stem diameter belongs to the moderate class.The genetic correlation between the plant height and stem diameter is positive and quite strong.-The number that is followed by the same alphabet in the same column are not significantly different at 0.01.
of the number of block; N = harmonik mean of the number of individuals per plot.

2 +
of family for character y.

Table 1 .
Geographical location and altitude of 3 populations of the natural distribution of Manglietia glauca progeny test in Candiroto Temanggung, Central Java.

Table 2 .
Analysis of variance of height and stem diameter of 2-year olds Manglietia glauca progeny test in Candiroto Temanggung Central Java.
a **) Significantly different at the level of 0.01

Table 3 .
The estimate value of individual heritability, family heritability, and genetic correlation of height and stem diameter of 2-years-old plot of progeny test in Candiroto Temanggung, Central Java.

Appendix 1 .
Duncan Multiple Range Test from height of Manglid at 2-years old in Candiroto Temanggung, The number that is followed by the same alphabet in the same column are not significantly different at 0.01.-Family number 1-15 comes from Tasikmalaya population; family number 16-25 comes from Sumedang population and family number 26 -100 comes from Sukabumi population.