Agroforestry is often seen as a sustainable land-use system for agricultural production providing ecosystem services. Intercropping with food crops leads to equal or higher productivity than monoculture and results in food production for industry and subsistence. Low rubber price and low labor productivity in smallholdings have led to a dramatic conversion of rubber plantations to more profitable crops. The literature analysis performed in this paper aimed at better understanding the ins and outs that could make rubber-based agroforestry more attractive for farmers. A comprehensive search of references was conducted in March 2023 using several international databases and search engines. A Zotero library was set up consisting of 415 scientific references. Each reference was carefully read and tagged in several categories: cropping system, country, main tree species, intercrop type, intercrop product, level of product use, discipline of the study, research topic, and intercrop species. Of the 232 journal articles, 141 studies were carried out on rubber agroforestry. Since 2011, the number of studies per year has increased. Studies on rubber-based agroforestry systems are performed in most rubber-producing countries, in particular in Indonesia, Thailand, China, and Brazil. These studies focus more or less equally on perennials (forest species and fruit trees), annual intercrops, and mixed plantations. Of the 47 annual crops associated with rubber in the literature, 20 studies dealt with rice, maize, banana, and cassava. Agronomy is the main discipline in the literature followed by socio-economy and then ecology. Only four papers are devoted to plant physiology and breeding. The Discussion Section has attempted to analyze the evolution of rubber agroforestry research, progress in the selection of food crop varieties adapted to agroforestry systems, and to draw some recommendations for rubber-based agroforestry systems associated with food crops.

Agroforestry is often seen as a sustainable land-use system for agricultural production providing ecosystem services. Intercropping with food crops leads to equal or higher productivity than monoculture and results in food production for industry and subsistence. Low rubber price and low labor productivity in smallholdings have led to a dramatic conversion of rubber plantations to more profitable crops. The literature analysis performed in this paper aimed at better understanding the ins and outs that could make rubber-based agroforestry more attractive for farmers. A library was set-up consisting of 415 scientific references. Of the 232 journal articles, 141 studies were carried out on rubber agroforestry. Since 2011, the number of studies per year has increased. Studies on rubber-based agroforestry systems are performed in most rubber producing countries, in particular in Indonesia, Thailand, China and Brazil. These studies focus more or less equally on perennials (forest species and fruit trees), annual intercrops and mixed plantations. Of the 47 annual crops associated with rubber in the literature, 20 studies dealt with rice, maize, banana and cassava. Agronomy is the main discipline in the literature followed by socio-economy and then ecology. Only 4 papers are devoted to plant physiology and breeding. The discussion section has attempted to analyze the evolution of rubber agroforestry research, progress in the selection of food crop varieties adapted to agroforestry systems, and to draw some recommendations for rubber-based agroforestry systems associated with food crops.

Salah satu cara pengendalian jamur akar putih (JAP) yang memiliki potensi besar untuk dikembangkan dimasa mendatang adalah secara biologi dengan memanfaatkan mikroba antagonis. Pada berbagai komoditas termasuk tanaman karet, bakteri endofitik antagonis telah dimanfaatkan untuk menghambat pertumbuhan patogen. Penelitian ini dilakukan untuk mengeksplorasi, mengidentifikasi bakteri endofitik dari tanaman karet serta menguji potensinya sebagai antagonis terhadap Rigidoporus microporus. Lima isolat berhasil diisolasi dari tanaman sehat di areal endemik JAP (isolat A10, A14, A16) dan areal non endemik JAP (isolat GN1, GN2). Uji oposisi langsung menunjukkan isolat A10 memiliki zona penghambatan terbesar (0,3 cm) pada 4 hari setelah inokulasi dibandingkan isolat lainnya. Identifikasi secara molekuler berdasarkan sekuens gen parsial 16S rRNA dan gen gyrase subunit B terhadap isolat A10 adalah Bacillus cereus. Aktivitas enzim protease ditunjukkan oleh isolat A10 pada medium skim milk dan kemampuannya mencairkan gelatin pada hari keenam setelah inokulasi. Kemampuan menghambat filtrat ekstraseluler yang diuji dengan metode paper disk belum menunjukkan zona penghambatan yang konsisten pada tiap konsentrasi filtrat ekstraseluler yang diberikan. Pada hari ketiga setelah inokulasi (HSI) tidak terdapat perbedaan nyata antar perlakuan. Pengujian lebih lanjut terhadap B. cereus isolat A10 perlu dipertimbangkan kembali karena potensi antagonismenya yang masih lemah terhadap R. microporus dan adanya potensi lain sebagai penyebab penyakit bagi manusia.

The physical and chemical properties of the growing medium for root trainer of rubber are critical to support plant growth. This study aimed to obtain the best medium for growing rootstock rubber seedlings in the root trainer. Rubber clone PR 300 seeds were germinated for 21 days, then raised in root trainer pots for five months. The treatments evaluated were a mixture of cocopeat, Rawapening peat, and manure at different ratios. The experiment was designed in a Randomized Block Design, three replications, 30 plants per replicate, totaling 720 plants. The observed variables were N, P, K, Mg, C-organic content, pH, and cation exchange capacity of cocopeat, peat, and manure, as well as plant growth (height, stem diameter, wet weight, and dry weight). ANOVA used for analyzing data, followed with the Duncan Multiple Range Test at 5% level. The results showed that there were three best root trainer media for PR 300 rubber rootstock seedlings were a mixture of cocopeat + peat (1:1), cocopeat + peat + manure (1:2:1), and cocopeat + peat + manure (2:1:1). The growth and compactness of the roots are outstanding, so the seedlings are easily removed from the root trainer pots without significant damage. Based on the initiation and cost, the best root trainer medium is a mixture of cocopeat + peat + manure (1: 2:1). It is necessary to study the use of other types of peat soils apart from Rawapening. Also, it needs to be observed further plant growth after inoculation with the stem and after planting in the field.Keywords : Planting medium, Rawapening peat, rubber clone PR 300.AbstrakSifat fisik dan kimia media tanam di dalam wadah root trainer bibit karet sangat penting untuk mendukung pertumbuhan tanaman. Penelitian ini bertujuan mendapatkan media terbaik untuk pertumbuhan bibit batang bawah karet di dalam root trainer. Benih klon karet PR 300 dikecambahkan selama 21 hari pada bedeng pengecambahan kemudian dipindah-tanam dan dibesarkan selama 5 bulan dalam pot root trainer. Perlakuannya yaitu campuran cocopeat, gambut Rawapening, dan pupuk kandang (pukan) pada berbagai ratio, dan kontrol. Penelitian dirancang secara Acak Kelompok, tiga ulangan, masing-masing 30 tanaman, sehingga totalnya 720 tanaman. Variabel yang diamati yaitu kandungan N, P, K, Mg, C-organik, pH, dan kapasitas tukar kation dari cocopeat, gambut, dan pupuk kandang, serta pertumbuhan tanaman (tinggi, diameter batang, bobot segar, dan bobot kering). Data dianalisis dengan ANOVA, kemudian Duncan Multiple Range Test pada taraf 5%. Hasil penelitian menunjukkan bahwa ada tiga macam media root trainer terbaik untuk bibit batang bawah karet klon PR 300 yaitu campuran cocopeat + gambut (1:1), cocopeat + gambut + pukan (1:2:1), dan cocopeat + gambut + pukan (2:1:1). Pertumbuhan dan kekompakan akar sangat baik sehingga bibit mudah dilepas dari root tainer tanpa kerusakan berarti. Berdasarkan kepraktisan dan biaya maka media root trainer terbaik adalah campuran media cocopeat + gambut + pukan (1:2:1). Perlu dilakukan kajian mengenai pemanfaatan tanah gambut jenis lainnya selain dari Rawapening. Selain itu, juga perlu diamati lebih lanjut pertumbuhan tanaman setelah diokulasi dengan batang atas maupun setelah ditanam di lapangan.Kata kunci : Gambut Rawapening, klon karet PR 300, media tanam.

The architectural characteristics of rubber trees are increasingly important in the context of climate change. Branching, canopy shape and growth pattern have to be adapted to monocropping and intercropping systems to foster latex and wood production, wind-tolerance, light availability and microclimate for intercrops, and soil stability and fertility. This study aimed to identify key architectural traits that could be used in breeding programs as well as chromosomal regions underlying QTLs that could be targeted for marker-assisted selection. Five quantitative (height of bole, trunk girth, estimated bole volume, number of terminal branches and apical shoots) and five qualitative (tree straightness, axillary shoot score, type of crown and axillary shoot, diameter of axillary shoot) architectural traits were phenotyped in a segregating population derived from clones PB 260 and SP 217. The frequencies of categories for each qualitative architectural variable were analysed as quantitative variables. A principal component analysis performed with these traits showed that trunk girth, estimated bole volume, round crown and medium diameter of axillary branches are negatively correlated with small diameter of axillary branches and conical type of crown. Seven architectural variables have heritability greater than 0.50. Twenty quantitative trait loci and their underlying genes and functions were pinpointed using the high-density genetic map previously constructed and an improved high-quality genome of the parent clone PB 260. Of the 680 genes found in chromosomal regions under QTLs, 19 genes have a function directly involved in plant development such as transcription factors related to the regulation of shoot apical meristem (SAM) and vascular cambium activity (WUSCHEL). A literature review was also conducted to provide additional insights into tree architecture and its impacts on agricultural systems. This first genetic analysis of architectural traits in rubber revealed that seven traits (trunk girth, bole height, estimated bole volume, number of apical branches, diameter of axillary branches, number of terminal branches and type of crown) could play a major role in rubber breeding both for monoculture and agroforestry single and double row systems. Chromosomal regions harbouring developmental genes could be used to develop specific strategy of marker-assisted selection.