Populasi Serangga Penyerbuk Kelapa Sawit Elaeidobius kamerunicus Faust dan Pengaruhnya terhadap Nilai Fruit Set pada Tanah Berliat, Berpasir dan Gambut di Kalimantan Tengah, Indonesia

Abstract

Population of soil palm weevil pollinator Elaeidobius kamerunicus FAUST and its impact on fruit setvalue at clay, sandy and peat soil types in central Kalimantan, di IndonesiaOil palm weevil pollinator Elaeidobius kamerunicus Faust plays an important role in the increasing oilpalm fruit set value. Along with the development of oil palm, fruit set problems occurred in recentdecades in some parts of Indonesia. An experiment was carried out on a seven years old oil palmplantation located at Selangkun Estate, Kotawaringin Barat, Central Kalimantan, Indonesia to find outthe influence of population E. kamerunicus on pollination efficiency at clay, sandy and peat soil types.Relative to other soil types, a high weevil population on male (50,811 weevils/ha ; 72 weevils/spikelet)and female (219 weevils) inflorescences had been recorded at clay soil. Fruit set value on clay soil 58.9%and significantly different with sandy soil of 49.8% and peat soil of 46.4%. Population E. kamerunicusper ha influenced fruit set value at clay, sandy and peat soil types. Number of E. kamerunicus visitedfemale inflorescences did not influenced fruit set value at clay, sandy and peat soil types.Keywords: Clay soil, Elaeidobius kamerunicus, fruit set, peat soil, population, sandy soil ABSTRAKSerangga penyerbuk kelapa sawit Elaeidobius kamerunicus FAUST berperan penting dalam peningkatannilai fruit set kelapa sawit. Seiring dengan perkembangan kelapa sawit, adanya permasalahan nilai fruitset telah terjadi dalam beberapa kurun waktu di beberapa wilayah Indonesia. Penelitian dilakukan diperkebunan kelapa sawit yang telah berumur tujuh tahun, berlokasi di Selangkung, Kotawaringin Barat,Kalimantan Tengah, Indonesia dan bertujuan untuk mengetahui pengaruh populasi E. Kamerunicusterhadap efisiensi penyerbukan pada tipe tanah liat, pasir dan gambut. Berdasarkan tipe tanahdilaporkan bahwa tingginya populasi kumbang pada bunga jantan yaitu (50.811 kumbang/ha; 72kumbang/spikelet) dan bunga betina yang sedang mekar (219 kumbang) pada tipe tanah berliat.Adapun, nilai fruit set pada tanah liat sebesar 58,9% dan berbeda nyata dibandingkan dengan tanahberpasir (49,8%) dan gambut (46,4%). Populasi E. kamerunicus per ha berpengaruh terhadap nilai fruitset pada tipe tanah liat, pasir dan gambut. Namun, jumlah E. kamerunicus yang mengunjungi bungabetina yang sedang mekar tidak berpengaruh terhadap nilai fruit set pada tipe tanah liat, pasir dangambut.Kata Kunci : Elaeidobius kamerunicus, Fruit set , Populasi, Tanah Gambut, Tanah liat, Tanah Pasir

POPULATION DENSITY OF Elaeidobius kamerunicus Faust IN DIFFERENT SPIKELET POSITION AT ANTHESISING MALE INFLORESCENCE OF Elaeis guineensis Jacq. IN SABAH AND SARAWAK, MALAYSIA

“…Throughout the period of this study, the weevil population density per spikelet fluctuated, from as high as more than 35 weevils spikelet -1 to less than 10 weevils spikelet -1 . Apparently, this trend was also reported in previous studies (Cik Mohd Rizuan et al, 2013;Syarifah Nadiah and Idris, 2016;Lubis et al, 2017;Nurul Fatihah et al, 2018). As highlighted by Khaliq et al (2014), the insect population dynamics can be influenced by both abiotic and biotic factors.…”

“…Compared to the study locations on the peat soil areas, higher weevil population density per spikelet was observed in sites located on mineral soil areas. Similar results were also reported by Lubis et al (2017). As the age profile and the planting materials of the palms in all study locations were more or less the same, the differences in terms of the weevil population could be attributed to the different types of soil that the oil palms were planted on.…”

Kajian Penunasan Berat Pelepah terhadap Kuantitas dan Kualitas Bunga Jantan Kelapa Sawit serta Ketertarikan Elaeidobius kamerunicus FAUST

“…Sementara itu, tingkat penurunan produksi polen kering per tandan, viabilitas polen, dan tingkat kemunculan kumbang pada siklus berikutnya cenderung fluktuatif dari 3 kali pengamatan 1-2 tahun setelah aplikasi pertama (Tabel 4). Studi yang dilakukan oleh Lubis et al (2017) pada perkebunan kelapa sawit areal tanah berliat, berpasir, dan gambut menunjukkan bahwa kumbang E. kamerunicus paling banyak berkunjung pada bunga jantan kelapa sawit mekar di kebun lahan berliat kemudian diikuti di kebun berpasir dan paling sedikit pada areal gambut. Areal berliat lebih sesuai diperuntukkan sebagai perkebunan kelapa sawit sementara ada beberapa faktor pembatas pada areal berpasir dan gambut (Corley dan Tinker, 2016).…”

Communities of oil palm flower-visiting insects: investigating the covariation of Elaeidobius kamerunicus and other dominant species

“…The production of oil palm, in terms of weight of bunches and the number of fruits set, has increased after the introduction of E. kamerunicus to Indonesia (Lubis, Sudarjat & Dono, 2017). A high oil palm fruit set (i.e., above 75%) requires a population of at least 20,000 E. kamerunicus individuals per hectare (Donough, Chew & Law, 1996).…”