Prof Ulfah Juniarti Siregar Explains the Breeding Method of Boktor Pest Resistant Superior Sengon

Sengon wood in Indonesia is an important export commodity which is also used to meet the needs of the national timber industry. This wood is usually planted by the people in community plantation forests. In 2019, sengon surface area has reached 315 thousand hectares on the island of Java. This amount reaches nine percent of the area of all other types of wood.

Prof Ulfah Juniarti Siregar, Lecturer in the Department of Silviculture, Faculty of Forestry and Environment (Fahutan) IPB University explained that there are still problems in the sengon plantation forest. Mainly boktor pest attack and tumor rust disease. These pests and diseases directly attack the wood, which can significantly reduce productivity.

“Until now, various control methods have been tried, but there is no method that is effective and efficient, because the plant area is very wide,” she explained in the 15th Friday Scientific Sharing Seminar – Genetic Engineering Research Center, National Research and Innovation Agency (BRIN), (03/03).

According to her, the intensity of attacks on monoculture forests can reach more than 50 percent. Meanwhile, in mixed forests it reached 12 percent. If not controlled, the loss can reach 70 percent. “Therefore, one of the efforts to prevent further losses is to plant superior sengon that is resistant to pests and diseases,” she continued.

She has conducted multigenic and multi-transcript research to explore sengon trees which are resistant to boktor pests and tumor rust disease. This is motivated by the high genetic diversity of sengon on the island of Java. “The hope is to carry out genetic selection for superior sengon through breeding efforts,” she added.

She added, this research was conducted by studying the activity of trypsin and alpha amylase enzymes in boktor larvae. It was found that there were several trees that were resistant because they contained inhibitors of this enzyme. Activity inhibitors in healthy trees are higher than in susceptible trees.

“These findings indicate the presence of genes coding for resistance to pests and diseases, so a test for sengon progeny was carried out in endemic places,” he said. He explained, the nature of sengon resistance is controlled by genetic factors and passed on to the next generation. Resistant parent trees will produce more resistant offspring than susceptible trees.

“Furthermore, clustering of accessions that are resistant to boktor pests and tumor rust disease is carried out based on microsatellite molecular markers. But there are still many accesions that cannot be separated, so a new approach is needed to be able to distinguish resistant and susceptible plants in breeding efforts,” said the Professor of IPB University.

Advanced approaches are carried out by assisting resistant genes using PCR and cloning. Further transcriptomic analysis was also carried out to determine susceptibility and resistance genes. As a result, resistant trees have expression of genes related to pest and disease resistance.

“The development of SNP (single nucleotide polymorphism) markers from resistance-related genes shows that markers can be used to accelerate the breeding of resistant sengon based on genome wide selection,” she said. (MW) (IAAS/YMK)