TEKNOLOGI TUMPANGSARI KARET - TANAMAN PANGAN: KENDALA DAN PELUANG PENGEMBANGAN BERKELANJUTAN / Technology of Rubber-Crop Intercropping: Constraints and Opportunities of Sustainable Development - Sahuri Sahuri (Jurnal Penelitian dan Pengembangan Pertanian, 2019)
Rubber farmer income is not stable because the latex price is still fluctuative and tend to be low. The application of rubber-crop intercropping is one the strategies in increasing of land productivity and rubber farmer income. Farmers generally plant rubber with a standard single-row spacing of rubber (SR) 6-7 m x 3 m (475- 550 trees/ha), so the row-spacing area could be planted with crops up to 2 years. Furthermore, rubber canopy closure which cover surface of land could intensively reduce 55% of light intensity and 60% of crop yield. This paper explains about constraints and opportunities of development of rubber-crop intercropping technology to increase rubber farmer income and food production sustainability. One aspect that are concerned about is changing the standard single-row spacing (SR) to double-row spacing (DR). This aspect could be useful to enlarge the rubber spacing area land and thus the crops as intercropping could be properly planted. Crops are easier to get sunlight, temperature, and water if the crops are planted in DR system. However, population of rubber plant is slightly reduced and thus latex yield is also relatively declined comparing with SR system. Nevertheless, the DR system as rubber-crop intercropping has a good opportunity to develop for long term period, because light penetration area of 3-4 m from the row of rubber plant is still more than 80% on 8-9 years old of rubber plant. The development of rubber-crop intercropping technology could protect rubber farmers from fluctuation of rubber price and also enhance additional value. The analysis shows DR with upland rice, corn, and soybean is feasible to be developed with 1.98 of a marginal benefit cost ratio (MBCR).Keywords: Rubber, rubber spacing, intercropping, food-crops AbstrakPendapatan petani karet belum stabil karena harga lateks berfluktuasi dan cenderung rendah. Penerapan tumpangsari karet - tanaman pangan merupakan salah satu strategi dalam meeningkatkan produktivitas lahan dan pendapatan petani karet. Petani umumnya menanam karet dengan sistem jarak tanam tunggal (JT) 6 - 7 m x 3 m (476 - 550 pohon/ha) sehingga lahan di antara tanaman karet hanya dapat ditanami tanaman pangan sampai tanaman pokok berumur 2 tahun. Selanjutnya tajuk tanaman karet sudah menutup permukaan lahan sehingga mengurangi intensitas cahaya sekitar 55% dan menurunkan hasil tanaman pangan sampai 60%. Tulisan ini membahas kendala dan peluang pengembangan teknologi tumpangsari karet - tanaman pangan dalam upaya peningkatan pendapatan petani dan produksi pangan secara berkelanjutan. Aspek yang menjadi perhatian dalam hal ini adalah mengubah sistem jarak tanam tunggal (JT) menjadi jarak tanam ganda (JG) agar ruang terbuka di antara tanaman karet lebih lebar untuk ditanami tanaman pangan sebagai tanaman sela. Pada areal di antara tanaman karet sistem JG, tanaman pangan lebih mudah mendapatkan sinar matahari, suhu, dan air, namun populasi tanaman karet sedikit berkurang, sehingga hasil lateks juga relatif berkurang dibanding tanaman karet sistem JT. Meski demikian, areal pertanaman karet sistem JG lebih berpeluang bagi pengembangan tumpangsari karet - tanaman pangan dalam jangka panjang, karena sampai tanaman karet berumur 8-9 tahun, penetrasi cahaya pada areal jarak 3-4 m dari barisan tanaman karet masih lebih dari 80%. Pengembangan teknologi tumpangsari karet - tanaman pangan dapat melindungi petani dari fluktuasi harga karet dan memberikan nilai tambah. Hasil analisis menunjukkan tumpangsari karet sistem JG dengan padi gogo, jagung, dan kedelai layak dikembangkan dengan marginal benefit cost ratio (MBCR) 1,98.Kata kunci: Karet, jarak tanam karet, tumpangsari, tanaman pangan