Engineered bamboo: The promising material for building and construction application in Indonesia

There is a rising gap between supply and demand of wood as building and construction materials. The search of alternative materials to fill in the gap is an urgent concern. Bamboo is one of locally abundant resources; 88 out of 135 species growth in Indonesia is an endemic. It is a renewably material and has comparable characteristics to wood. Notable efforts to reduce the variability of raw bamboo have led to the improved physical and mechanical properties of the engineered bamboo. Laminated bamboo and hybrid laminated bamboo-wood had superior wood strength in comparison to the raw materials. Laminated bamboo produced from andong (Gigantochloa pseudoarundinacea (Steud.) Widjaja), mayan (Gigantochloa robusta Kurz), vertically laminated andong bamboo comparable to wood strength class I, I-II and II, respectively. Furthermore, hybrid laminated bamboo-wood andong-manii (Maesopsis eminii Engl.), andong-mayan-jabon (Anthocephalus cadamba (Roxb.) Miq.) comparable to wood strength class II and III, respectively. The properties improvement of engineered bamboo demonstrates the potential application of laminated bamboo as a substitution for building and construction material.

Effect of Soaking Treatment on Germination of Hard Coated Tropical Forest Tree Seeds

Seed germination and seedling growth performance of Maesopsis eminii and Terminalia catappa under different water soaking treatments were evaluated for 120 days under nursery conditions. A total of 1400 seeds were pre-treated with hot (95oC) and cold water (ambient temperature) by soaking for 12, 24 and 48 hours with a control of no soaking. The seeds were sown directly into polythene pots filled with uniform growth medium (top forest soil, sand and clay soilmixed in a ratio of 5:3:2) to avoid disturbance of the root system after germination. The seeds were sown in a randomized block design with seven treatments and three replicates. Data were analysed using ANOVA in GenStat v18. Results indicated that soaking enhanced seed germination. Soaking of seeds in cold water for 12 hours resulted into higher germination (90% for Terminalia catappa and 85% for Maesopsis eminii) than the control (48%). Soaking period and water temperature significantly influenced seedling vigour (F value = 0.962; p = 0.038). Soaking seeds in cold water for 24 hours enhanced Maesopsis eminii seedling growth by 8.0 cm Terminalia catappa seedlings by 7.4 cm. Seed dormancy, germination percentage and growth performance in hard coated seeds such as Maesopsis eminii and Terminalia catappa can be broken by soaking in cold water for 12-24 hours. Pre-germination treatments significantly influences the germination and seedling growth. Keywords: Maesopsis eminii, Terminalia catappa, seeds, pre-germination, soaking.

Disease prevalence and shade tree diversity in smallholder cocoa (Theobroma cacao) farms: case of Bundibugyo District, Western Uganda

Cocoa (Theobroma cacao) growing systems in Uganda consists of shade systems with different tree species. Tree shade systems are the pure stand trees in the cocoa plantation which have been attributed towards reducing on pests and disease incidences, shade provision, boosting fertility, Agro biodiversity, fodder and improving production. The study was aimed at identifying potential shade tree species that can minimize disease threats on cocoa farms. Eighty-two cocoa farmers were reached out of 120 cocoa farmers in Bundibugyo that possessed at least five acres of the plantation in a purposive sampling approach. Black pod disease was non-significantly associated with presence of shade tree diversities. It was established that incidence of black pod rot disease was non-significantly associated with presence of all shade tree species; association between witch’s broom disease incidence with presence of Maesopsis eminii was highly significant (χ2= 55.41, (p<0.05); Association between witch’s broom and presence of Persea Americana (χ2=9.79), (p<0.05), Eucalyptus globulus (χ2=16.71), (p<0.05), Markhamia obtusifolia (χ2=3.95), (p<0.001), schefflera actinophylla (χ2=4.32), (p<0.001), Mangifera indica (χ2=6.46), (p<0.001) was significant though these trees were planted in small numbers. Association between frosty rot disease incidence with presence of Maesopsis eminii was highly significant (χ2= 25.90), (p<0.05). there was a significant association between frosty with presence of Eucalyptus globulus (χ2=6.76), (p<0.05); Mangifera indica (χ2=4.85), (p<0.001); though these trees were planted in small numbers. There was a highly significant association between swollen shoot virus with presence of Maesopsis eminii (χ2= 31.55), (p<0.05), and Cinnamomum tamala (χ2= 19.22), (p<0.05). Association between die back disease incidence with presence of Maesopsis eminii was highly significant (χ2= 52.73), (p<0.05).

Field-based Evidence of the Black Coffee Twig Borer infesting Maesopsis eminii in Coffee Agro-systems in Kiboga District, Uganda

Despite Ugandan coffee farmers’ preference for Maesopsis eminii as a shade tree, the species is an alternate host for the black coffee twig borer, Xylosandrus compactus (Eichhoff)—a major insect pest of coffee in the country. Wilting and drying of leaves and branches of young M. eminii trees (<5 m tall) observed in Kiboga District, Uganda. The branches were trimmed off the trees, separated into primary and secondary branches and then the percentage of those possessing characteristic X. compactus entry holes determined separately. Additionally, the number of entry holes on both primary and secondly branches was established to determine the extent of damage of X. compactus. X. compactus characteristic holes were observed on both primary and secondary branches of M. eminii - percentage of branches having entry holes and the number of entry holes higher on primary than secondary branches. Dissecting the branches at the entry holes revealed various life stages of X.compactus in the gallery, proving that the damage was due to the pest. Presence of this pest on trees that are inter-planted in the coffee agroforestry systems presents a dilemma in managing it. Therefore, research should be geared towards designing management strategies for the pest in the coffee agroforestry systems. In the meantime, farmers should always trim-off and burn all infested parts from coffee and other plants inter-planted in it.

Analisis Potensi Hutan Rakyat Dalam Mendukung Kabupaten Kuningan Sebagai Kabupaten Konservasi

Sebagai kabupaten konservasi, Kabupaten Kuningan tidak bisa memproduksi hasil hutan kayu dalam skala besar karena kondisi hutannya sebagian besar merupakan kawasan konservasi dan hutan produksi terbatas, selain itu berada pada wilayah rawan gerakan tanah. Hal tersebut menyebabkan terjadinya defisit kebutuhan kayu di wilayah ini. Salah satu alternatif untuk memenuhi kebutuhan kayu adalah melalui produksi hutan rakyat. Saat ini produksi hutan rakyat masih rendah tetapi berpotensi besar, untuk itu dibutuhkan perencanaan yang baik. Tujuan penelitian ini adalah: (1) mendapatkan jenis tanaman yang potensial berdasarkan referensi masyarakat dan identifikasi tingkat kelayakan dari pengusahaan hutan rakyat; (2) memetakan kesesuaian dan ketersediaan lahan untuk pengembangan hutan rakyat. Analisis data pada penelitian ini mencakup analisis data spasial berbasis Sistem Informasi Geografi (SIG), analisis finansial, identifikasi jenis tanaman hutan rakyat prioritas menggunakan Analytical Hierarchy Process (AHP) dan Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). Hasil penelitian menunjukkan lahan yang sesuai dan tersedia untuk Sengon yaitu seluas 9.173 Ha, Mahoni seluas 9.938 Ha, Afrika seluas 10.687 Ha, dan Jati seluas 10.431 Ha. Analisis finansial menunjukkan bahwa pengusahaan hutan rakyat untuk Sengon, Afrika, dan Jati layak untuk dikembangkan terlihat dari nilai NPV, BCR, dan IRR yang memenuhi kriteria layak walaupun pada tingkat suku bunga yang berbeda, sedangkan untuk Mahoni hanya layak pada suku bunga 7,5%. Arahan jenis tanaman hutan rakyat yaitu, pada bagian utara dan timur untuk sengon (Paraserianthes falcataria) dan Jati (Tectona grandis), bagian barat dan selatan untuk mahoni (Swietenia mahogany) dan Afrika (Maesopsis eminii Engl.)

IMAGING TREE ROOT ZONE GEOMETRY USING ELECTRICAL RESISTIVITY TOMOGRAPHY

Root zone geometry research is usually done in a conventional way which is destructive, time-consuming, and requires a considerable cost. Several non-destructive measurements used geophysical methods have been developed, one of which is the Electrical Resistivity Tomography (ERT) method. Tree root zone determination using ERT has been carried out in Kiara Payung area, Sumedang, West Java, with Maesopsis eminii tree as the object study. A total of 29 ERT lines were measured using dipoledipole configuration with electrodes spacing of 50 cm. The results of two-dimensional (2D) and three-dimensional (3D) inversion modeling show that the ERT method has been successfully imaging the tree root zone. The root zone is characterized as 100-700 Ωm with an elliptical shape geometry of the root plate. The root radius is estimated to be 4-5 m from the stem, the root zone diameter reaches 8-9 m at the shallow soil surface and the root zone depth is approximately 2-2.5 m. ABSTRAK Pencitraan geometri zona perakaran pohon menggunakan electrical resistivity tomography. Penelitian geometri zona perakaran biasa dilakukan dengan cara konvensional yang destruktif, memakan waktu, dan membutuhkan biaya yang tidak sedikit. Beberapa pengukuran non-destruktif menggunakan metode geofisika telah dikembangkan, salah satunya adalah metode Electrical Resistivity Tomography (ERT). Penentuan zona perakaran pohon menggunakan metode ERT telah dilakukan di daerah Kiara Payung, Sumedang, Jawa Barat, dengan pohon Maesopsis eminii sebagai objek studi. Sebanyak 29 lintasan ERT diukur menggunakan konfigurasi dipole-dipole pada dengan jarak antar elektroda 50 cm. Hasil pemodelan inversi dua dimensi (2D) dan tiga dimensi (3D) menunjukkan bahwa metode ERT telah berhasil mencitrakan zona perakaran pohon. Zona perakaran teridentifikasi berada pada nilai resistivitas 100-700 Ωm dengan root plate dan root cross-sections berbentuk elips. Radius akar diperkirakan sejauh 4-5 m dari pangkal batang, sedangkan diameter zona perakaran mencapai sekitar 8-9 m di permukaan tanah dangkal dan kedalaman zona perakaran diperkirakan antara ~2-2.5 m.