PERTANIKA JOURNAL OF TROPICAL AGRICULTURAL SCIENCE

The replanting practice of rubber monocropping in Southern Thailand has depleted soil fertility. Most rubber planted areas in the region were under intensive chemical fertilization resulting in less soil organic matters and root proliferation. With the instability of rubber prices, some rubber farmers converted from monocropping into intercropping. Integrated fertilization in which mixed organic-inorganic fertilizers are combined with organic soil amendments could be considered in a rubber-based intercropping system to increase land productivity with cost-saving fertilization by rehabilitating soil properties. A study was conducted at a rubber-salacca intercropping farm comprised of 14-year-old mature rubber trees associated with eight-year-old salacca palms to identify the consequences of the integrated fertilization combined with two organic soil amendments: humic acid (HSA); chitosan (CSA). Changes in soil organic matter (SOM), leaf area index (LAI), fine root traits, tree physiological status, and crop productions under the two integrated fertilization were compared against the controlled application of conventional chemical fertilizer. The CSA application increased the SOM in the topsoil layer by 80%. In the 21 – 40 cm soil depth, the rubber roots treated with HSA and the salacca palm roots treated with CSA showed greater fine root length density (FRLD). Under CSA, the physiological status of the rubber trees showed less stress. The treatments of HSA and CSA showed 145% and 72%, respectively, higher in total production of salacca palm than that of the chemical fertilization. Improvements in the soil fertility, the root’s function, the crops’ yields, and the tree physiological status were consequences as complementarity in the system under the integrated fertilizations.

• Adou, C. Y. B., Atsin, O. J. G., Essehi, J. L., Ballo, K. E., Soumahin, F. E., Obouayeba, P. A., Kouakou, H. T., & Obouayeba, S. (2017). Latex micro diagnosis, modern management tool of rubber plantation of clones with moderate metabolism GT 1, RRIC 100 and BPM 24. Journal of Applied Biosciences, 121, 12098-12109. https://doi.org/10.4314/jab.v121i1.1

• Atsin, G. J. O., Soumahin, E. F., Kouakou, T. H., Elabo, A. E. A., Okoma, K. M., & Obouayeba, S. (2016). Agronomic potential of some rubber tree clones (Hevea brasiliensis) of the fast metabolic activity class in the absence of hormonal stimulation in southwestern of Côte d’Ivoire. American Journal of Experimental Agriculture, 13(4), 1-13. https://doi.org/10.9734/AJEA/2016/26930

• Bianchi, S., Cahalan, C., Hale, S., & Gibbons, J. M. (2017). Rapid assessment of forest canopy and light regime using smartphone hemispherical photography. Ecology and Evolution, 7(24), 10556-10566. https://doi.org/10.1002/ece3.3567

• Buyukkeskin, T., Akinci, S., & Eroglu, A. E. (2015). Effects of humic acid on root development and nutrient uptake of Vicia faba L. (broad bean) seedlings grown under aluminum toxicity. Communications in Soil Science and Plant Analysis, 46(3), 277-292. https://doi.org/10.1080/00103624.2014.969402

• Bybee-Finley, K. A., & Matthew, R. R. (2018). Advancing intercropping research and practices in industrialized agricultural landscapes. Agriculture, 8(6), 80. https://doi.org/10.3390/agriculture8060080

• Cahyo, A. N., Ardika, R., Saputra, J., & Wijaya, T. (2014). Acceleration on the growth of rubber planting materials by using folia application of humic acid. Agrivita, 36(2), 112-119. https://doi.org/10.17503/agrivita.v36i2.397

• Chantuma, P., Lacote, R., Leconte, A., & Gohet, E. (2011). An innovative tapping system, the double cut alternative, to improve the yield of Hevea brasiliensis in Thai rubber plantations. Field Crops Research, 121(3), 416-422. https://doi.org/10.1016/j.fcr.2011.01.013

• Chen, C., Liu, W., Jiang, X., & Wu, J. (2017). Effects of rubber-based agroforestry systems on soil aggregation and associated soil organic carbon: Implication for land use. Geoderma, 299, 13-24. https://doi.org/10.1016/j.geoderma.2017.03.021

• Chen, Y. C., Yuan, S., Liu, H., Chen, Z., Zhang, Y., & Zhang, H. (2016). A combination of chitosan and chemical fertilizers improves growth and disease resistance in Begonia hiemalis Fotsch. Horticulture, Environment, and Biotechnology, 57, 1-10. https://doi.org/10.1007/s13580-016-0119-4

• Christophe, A. B. Y., Mathurin, O. K., Pacome, O. A., Olivier, A. G., Kouadio, B. E., Jean-Lopez, E., Jean, W. P., Francis, S. E., Hilaire, K. T., & Samuel, O. (2018). Latex micro diagnosis, modern management tool of rubber plantations of clones with active or rapid metabolism IRCA 18, IRCA 130, PB 235, PB 260 and PB 330. European Scientific Journal, 14(3), 385. https://doi.org/10.19044/esj.2018.v14n3p385

• Comas, L. H., Becker, S. R., Cruz, V. M., Byrne, P. F., & Dierig, D. A. (2013). Root traits contributing to plant productivity under drought. Frontiers in Plant Science, 4, 442. https://doi.org/10.3389/fpls.2013.00442

• Dharmakeerthi, R. S., Chandrasiri, J. A. S., & Edirimanne, V. U. (2013). Humic acid based liquid organic fertilizer improved the growth of nursery and immature rubber plants grown in Boralu soil series. Journal of the Rubber Research Institute of Sri Lanka, 93, 1-15. http://doi.org/10.4038/jrrisl.v93i0.1863

• Doungmusik, A., & Sdoodee, S. (2012). Enhancing the latex productivity of Hevea brasiliensis clone RRIM 600 using ethylene stimulation. Journal of Agricultural Technology, 8(6), 2033-2042.

• du Jardin, P. (2015). Plant biostimulants: Definition, concept, main categories and regulation. Scientia Horticulturae, 196, 3-14. https://doi.org/10.1016/j.scienta.2015.09.021

• Food and Agriculture Organization of the United Nations. (2016). Guidelines for the management of plant nutrients and their sources. In R. N. Roy, A. Finck, G. J. Glair, & H. L. S. Tandon (Eds.), Plant nutrition for food security: A guide for integrated nutrient management (pp. 141-192). FAO.

• Food and Agriculture Organization of the United Nations. (2020). Standard operating procedure for soil organic carbon. Walkley-Black method: Titration and colorimetric method. FAO.

• Gohet, E., Cavaloc, E., Cardoso, S., Cairo, I., Garcia, D., Rivano, F., Lacote, R., & Lesturgez, G. (2015). A first physiological assessment of latex clonal metabolic typology and rubber yield potential of “CMS” rubber tree clones. In Proceedings of International Rubber Conference (pp. 287-294). Agriculture Publishing House. https://doi.org/10.13140/RG.2.1.3007.4328

• Henry, A., Cal, A. J., Batoto, T. C., Torres, R. O., & Serraj, R. (2012). Root attributes affecting water uptake of rice (Oryza sativa) under drought. Journal of Experimental Botany, 63(13), 4751-4763. https://doi.org/10.1093/jxb/ers150

• Hougni, D. J. M., Chambon, B., Penot, E., & Promkhambut, A. (2018). The household economics of rubber intercropping during the immature period in Northeast Thailand. Journal of Sustainable Forestry, 37(8), 787-803. https://doi.org/10.1080/10549811.2018.1486716

• Jindo, K., Aparecida, M., Navarro, E. C., Perez-Alfocea, F., Hernandez, T., Garcia, C., Aguiar, N. O., & Canellas, L. P. (2012). Root growth promotion by humic acids from composted and non-composted urban organic wastes. Plant Soil, 353, 209-220. https://doi.org/10.1007/s11104-011-1024-3

• Jongrungrot, V., Thungwa, S., & Snoeck, D. (2014). Tree-crop diversification in rubber plantations to diversify sources of income for small-scale rubber farmers in Southern Thailand. Bois et Forets des Tropiques, 68(321), 21-32. https://doi.org/10.19182/bft2014.321.a31214

• Krishnan, A., Joseph, L., & Roy, C. B. (2019). An insight into Hevea – Phytophthora interaction: The story of Hevea defense and Phytophthora counter defense mediated through molecular signalling. Current Plant Biology, 17, 33-41. https://doi.org/10.1016/j.cpb.2018.11.009

• Langenberger, G., Cadish, G., Martin, K., Min, S., & Waibel, H. (2017). Rubber intercropping: A viable concept for the 21st century?. Agroforestry Systems, 91, 577-596. https://doi.org/10.1007/s10457-016-9961-8

• Li, Y., Fang, F., Wei, J., Wu, X., Cui, R., Li, G., Zheng, F., & Tan, D. (2019). Humic acid fertilizer improved soil properties and soil microbial diversity of continuous cropping peanut: A three-year experiment. Scientific Reports, 9, 12014. https://doi.org/10.1038/s41598-019-48620-4

• Maeght, J. L., Gonkhamdee, S., Clement, C., Isarangkool Na Ayutthaya, S., Stokes, A., & Pierret, A. (2015). Seasonal patterns of fine root production and turnover in a mature rubber tree (Hevea brasiliensis Mull. Arg.) stand-differentiation with soil depth and implications for soil carbon stocks. Frontiers in Plant Science, 6, 1022. https://doi.org/10.3389/fpls.2015.01022

• Montagnini, F. (2011). Can tree plantations serve as catalysts of secondary forest succession?. In F. Montagnini & C. Finney (Eds.), Restoring degraded landscapes with native species in Latin America (pp. 3-28). Nova Science Publishers.

• Nannipieri, P., Ascher, J., Ceccherini, M. T., Landi, L., Pietramellara, G., & Renella, G. (2017). Microbial diversity and soil functions. European Journal of Soil Science, 68(1), 12-26. https://doi.org/10.1111/ejss.4_12398

• National Statistical Office. (2013). Executive summary: 2013 Agricultural census, southern region. National Statistical Office.

• Obouayeba, S., Soumahin, E. F., Okoma, K. M., Boko, A. M. C. K., Dick, K. E., & Lacote, R. (2011). Relationship between tapping intensity and tapping panel dryness susceptibility of some clones of Hevea brasiliensis in Southwestern Côte d’Ivoire. Agriculture and Biology Journal of North America, 2(8), 1151-1159. https://doi.org/10.5251/abjna.2011.2.8.1151.1159

• Purwaningrum, Y., Asbur, Y., & Junaidi. (2019). Latex quality and yield parameters of Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg. clone PB 260 for different tapping and stimulant application frequencies. Chilean Journal of Agricultural Research, 79(3), 347-355. https://doi.org/10.4067/S0718-58392019000300347

• Purwaningrum, Y., Napitupulu, J. A., Siregar, T. H. S., & Hanum, C. (2015). Histology and physiology of BPM 1 clones with different exploitation systems. International Journal of Sciences: Basic and Applied Research, 21, 138-148.

• Rappaport, D., & Montagnini, F. (2014). Tree species growth under a rubber (Hevea brasiliensis) plantation: Native restoration via enrichment planting in southern Bahia, Brazil. New Forests, 45, 715-732. https://doi.org/10.1007/s11056-014-9433-9

• Romyen, A., Sausue, P., & Charenjiratragul, S. (2018). Investigation of rubber-based intercropping system in Southern Thailand. Kasetsart Journal of Social Sciences, 39(1), 135-142. https://doi.org/10.1016/j.kjss.2017.12.002

• Ruangkhanab, M., & Lim, M. (2005). Effect of chemical application on vegetative growth of longkong. Songklanakarin Journal of Science and Technology, 27(3), 629-868.

• Saelim, S., Sdoodee, S., & Chiarawipa, R. (2019). Monitoring seasonal fine root dynamics of Hevea brasiliensis clone RRIM 600 in Southern Thailand using minirhizotron technique. Songklanakarin Journal of Science and Technology, 41(2), 341-348. https://doi.org/10.14456/sjst-psu.2019.43

• Sainoi, T., Sdoodee, S., Lacote, R., & Gohet, E. (2017). Low frequency tapping systems applied to young-tapped trees of Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg. in Southern Thailand. Agriculture and Natural Resources, 51(4), 268-272. https://doi.org/10.1016/j.anres.2017.03.001

• Sawaguchi, A., Ono, S., Oomura, M., Inami, K., Kumeta, Y., Honda, K., Sameshima-Saito, R., Sakamoto, K., Ando, K., & Saito, A. (2015). Chitosan degradation and associated changes in bacterial community structures in two contrasting soils. Soil Science and Plant Nutrition, 61(3), 471-480. https://doi.org/10.1080/00380768.2014.1003965

• Selladurai, R., & Purakayastha, T. J. (2016). Effect of humic acid multinutrient fertilizers on yield and nutrient use efficiency of potato. Journal of Plant Nutrition, 39(7), 949-958. http://doi.org/10.1080/01904167.2015.1109106

• Sharp, R. G. (2013). A review of the applications of chitin and its derivatives in agriculture to modify plant microbial interactions and improve crop yields. Agronomy, 3(4), 757-793. https://doi.org/10.3390/agronomy3040757

• Sumantra, I. K., & Martiningsih, N. G. E. (2018). The agroecosystem of Salak Gulapasir (Salacca zalacca var. Amboinensis) in new development areas in Bali. https://www.researchgate.net/publication/342923683_The_Agroecosystem_of_Salak_Gulapasir_Salacca_zalacca_var_amboinensis_in_New_Development_Areas_in_Bali

• Sumantra, I. K., Ashari, S., Wardiyati, T., & Suryanto, A. (2012). Diversity of shade trees and their influence on the microclimate of agro-ecosystem and fruit production of Gulapasir salak (Salacca zalacca var. Amboinensis) fruit. International Journal of Basic and Applied Sciences, 12(6), 214-221.

• Sunpapao, A., & Pornsuriys, C. (2014). Effects of chitosan treatments on para rubber leaf fall disease caused by Phytophthora palmivora Butler – A laboratory study. Songklanakarin Journal of Science and Technology, 36(5), 507-512.

• Tang, L., Yin, D., Chen, C., Yu, D., & Han, W. (2019). Optimal design of plant canopy based on light interception: A case study with loquat. Frontiers in Plant Science, 10, 364. https://doi.org/10.3389/fpls.2019.00364

• Umami, I. M., Kamarudin, K. N., Hermansah, & Abe, S. S. (2019). Does soil fertility decline under smallholder rubber farming? The case of a West Sumatran lowland in Indonesia. Japan Agricultural Research Quarterly, 3(4), 279-297. https://doi.org/10.6090/jarq.53.279

• Vamerali, T., Bandiera, M., & Mosca, G. (2011). Minirhizotrons in modern root studies. In S. Mancuso (Ed.), Measuring roots as update approach (pp. 341-361). Springer. https://doi.org/10.1007/978-3-642-22067-8_17

• Vrignon-Brenas, S., Gay, F., Ricard, S., Snoeck, D., Perron, T., Mareschal, L., Laclau, J., Gohet, E., & Malagoli, P. (2019). Nutrient management of immature rubber plantations. A review. Agronomy for Sustainable Development, 39, 11. https://doi.org/10.1007/s13593-019-0554-6

• Wasson, A. P., Richards, R. A., Chatrath, R., Misra, S. C., Prasad, S. V. S., Regetzke, G. J., Kirkegaard, J. A., Christopher, J., & Watt, M. (2012). Traits and selection strategies to improve root systems and water uptake in water-limited wheat crops. Journal of Experimental Botany, 63(9), 3485-3498. https://doi.org/10.1093/jxb/ers111

• Weraduwage, S. M., Chen, J., Anozie, F. C., Morales, A., Weise, S. E., & Sharkey, T. D. (2015). The relationship between leaf area growth and biomass accumulation in Arabidopsis thaliana. Frontiers in Plant Science, 6, 167. https://doi.org/10.3389/fpls.2015.00167

• Wu, L., Jiang, Y., Zhao, F., He, X., Liu, H., & Yu, K. (2020). Increased organic fertilizer application and reduced chemical fertilizer application affect the soil properties and bacterial communities of grape rhizosphere soil. Scientific Reports, 10, 9568. https://doi.org/10.1038/s41598-020-66648-9

• Xianhai, Z., Mingdao, C., & Weifu, L. (2012). Improving planting pattern for intercropping in the whole production span of rubber tree. African Journal of Biotechnology, 11(34), 8484-8490. https://doi.org/10.5897/AJB11.3811

• Zhu, J., Qi, J., Fang, Y., Xiao, X., Li, J., Lan, J., & Tang, C. (2018). Characterization of sugar contents and sucrose metabolizing enzymes in developing leaves of Hevea brasiliensis. Frontiers in Plant Science, 9, 58. https://doi.org/10.3389/fpls.2018.00058