Slamet Susanto

Sago palm (Metroxylon sagu, Arecaceae) production in the eastern archipelago of Indonesia: variation in morphological characteristics and pith dry-matter yield.

Eleven local varieties of sago palm (Metroxylon sagu Rottb.) in southeast and north Sulawesi and in northern Maluku were studied: one variety with a weak black band on the back of the petiole: three varieties with a brown band on the back of the petiole: seven bandless varieties comprising two spineless, four short spine and one long spine types. Large variation in morphological characteristics and pith dry-matter yield were estimated at 13 to 34% and 55%, respectively. The difference in pith dry-matter yield is mainly attributed to trunk diameter and dry-matter percentage of pith. Trunk diameter was not affected by the length of growth period, which might reflect the palm’s own characteristics, such as genetic background and growth environment. The dry-matter percentage of pith was not related to any characteristics measured. The pith dry-matter yield was highest in the short spine type, followed by the spineless and the long spine types.RésuméDalam survey tersebut dipelajari sebelas varitas sagu lokal (Metroxylon sagu Rottb.) di Sulawesi Tenggara, Sulawesi Utara, dan Maluku Utara: satu varitas dengan pita sedikit hitam pada bagian belakang dari tulang daun: tiga varitas dengan pita coklat pada bagian belakang belakang dari tulang daun: tujuh varitas tanpa pita terdiri dari dua varitas tanpa duri, empat varitas duri pendek dan satu varitas duri panjang. Terdapat adanya keragaman pada karakteristik morfologi dan hasil bahan kering empulur batang yang diperkirakan beriurut-turut berkisar 13 sampai 34% dan 55%. Perbedaan pada hasil bahan kering empulur batang terutama tergantung pada diameter batang dan proporsi kering empulur batang. Diameter batang tidak dipengaruhi oleh panjangnya periode tumbuh; namun nampaknya lebih terkait dengan gambaran karakteristik khusus, seperti latar belakang genetik dan lingkungan tumbuhnya.Persen bobot kering empulur batang tidak ada hubungannya dengan berbagai karakteristik yang diteliti. Hasil bahan kering empulur batang tertinggi adalah pada tipe duri pendek (511kg/batang), diikuti tipe tanpa duri (417kg/batang) dan tipe duri panjang (329kg/batang).

Perbaikan Kualitas Buah Jambu Biji (Psidium guajava L.) Kultivar Kristal dengan Berbagai Warna dan Bahan Pemberongsong

ABSTRACT Kristal guava is one of the popular guava cultivars nowadays. The guava has white flesh and not-perfectly-round shaped that resembles a crystal and seedless. However, during the growth period fruit undergoes several physical and chemical changes and susceptible to insect infestation and other damage, all of which can reduce their commercial value and thus cause significant yield and economic losses. The aim of this research was to evaluate the influence of different color and bagging materials on guava fruit development and quality. The research was conducted at farmer farm located in Cikarawang Dramaga, from November 2013 to April 2014. This research was arranged in a randomized block design with one factor, consisted of ten treatments and five replications. The treatments were red plastic, yellow plastic, green plastic, blue plastic, sponnet with red plastic, sponnet with yellow plastic, sponnet with green plastic, sponnet with blue plastic, sponnet with transparent plastic and unbagged. Fruit quality assesment was conducted in Postharvest Laboratory of Agronomy and Horticulture Department, Bogor Agricultural University and Center for Tropical Horticultural Studies. The result showed that bagging improved fruit size, external quality and accelerated fruit maturity. Sponnet with red plastic bagging resulted in the biggest fruit at harvest. Sponnet with yellow or with red plastic baggings were able to maintain fruit peel smoothness up to 85%. Sponnet and plastic bagging resulted in better external quality than bagging with plastic only. Bagging did not show any effect on internal fruit quality. Keywords: colored bag, guava cv. Kristal, soluble solids content, sponnet, titratable acidity ABSTRAK Jambu ‘Kristal’ merupakan salah satu kultivar jambu biji yang sedang populer saat ini. Jambu Kristal memiliki daging buah berwarna putih, berbentuk bulat tidak beraturan serta berbiji sedikit. Selama pertumbuhan dan perkembangan buah mengalami berbagai perubahan fisik dan kimia dan rentan terhadap serangan hama, yang secara keseluruhan dapat mengurangi nilai komersial sehingga menyebabkan kehilangan yang signifikan dari segi hasil panen dan kerugian ekonomi. Tujuan dari penelitian ini adalah untuk menjelaskan pengaruh warna dan bahan pemberongsong terhadap perbaikan kualitas buah jambu ‘Kristal’. Penelitian dilaksanakan pada November 2013 sampai April 2014, di kebun petani yang berlokasi di Cikarawang, Dramaga, Bogor. Penelitian menggunakan Rancangan Acak Kelompok dengan satu faktor yaitu pemberongsongan buah, dengan sepuluh taraf dan lima ulangan. Perlakuan pemberonsongan menggunakan plastik merah, plastik kuning, plastik hijau, plastik biru, sponnet dan plastik merah, sponnet dan plastik kuning, sponnet dan plastik hijau, sponnet dan plastik biru, sponnet dan plastik bening serta tanpa pemberongsong. Pengujian kualitas buah dilakukan di Laboratorium Pascapanen Departemen Agronomi dan Hortikultura, Fakultas Pertanian, Institut Pertanian Bogor dan Laboratorium Pusat Kajian Hortikultura Tropika (PKHT) IPB. Hasil penelitian menunjukkan bahwa pemberongsongan memperbaiki pertumbuhan, kualitas eksternal dan mempercepat pematangan buah. Pemberongsongan sponnet dan plastik merah menghasilkan buah dengan ukuran terbesar pada saat panen. Pemberongsongan menggunakan sponnet dengan plastik kuning atau merah mampu menjaga kemulusan buah hingga 85%. Pemberongsongan sponnet dan plastik menghasilkan kualitas eksternal yang cenderung lebih baik dibandingkan pemberongsongan hanya dengan plastik. Pembrongsongan tidak berpengaruh nyata terhadap kualitas internal buah. Kata kunci: asam tertitrasi total, jambu ‘Kristal’, sponet , padatan terlarut total, pemberongsong berwarna

Pertumbuhan Tanaman Pamelo (Citrus maxima (Burm.) Merr.) pada Berbagai Komposisi dan Volume Media Tanam

ABSTRACT This study was aimed at determining the planting media composition and media volume for pummelo growth. A complete randomized design with two factors was arranged in this experiment. The first factor was planting media composition, consisting of (1) rice hull charcoal : soil = 1 : 1, (2) cocopeat : soil = 1 : 1, (3) cocopeat : rice hull charcoal = 1 : 1, (4) rice hull charcoal : cocopeat : soil = 1 : 1 : 1, and (5) soil as control. The second factor was media volume, namely 10, 20, and 30 L. The results showed that plant height, leaf number, root volume and P leaf concentration of pummelo grown in 30 L media were significantly higher than those of pummelo grown in 10 L media, but were not different from those of grown in 20 L media, except for leaf number. Plant height, root volume and N leaf content of pummelo grown in rice hull charcoal : soil relatively were higher than those grown in rice hull charcoal : cocopeat. Planting media composition of rice hull charcoal : cocopeat had N and C content, C/N ratio, organic matter, K2O and cation exchange capacity higher, but had water content, bulk density, particle density lower than other growing medium. The most suitable planting medium for potted pummelo was rice hull charcoal : soil, and 20 L medium volume was still suitable until 24 WAP (weeks after planting). Key words: cocopeat, N and P leaves content, rice hull charcoal, root volume, ABSTRAK Penelitian ini bertujuan untuk mengetahui komposisi dan volume media tanam yang sesuai untuk pertumbuhan tanaman pamelo. Penelitian ini menggunakan rancangan acak lengkap (RAL) faktorial dengan dua faktor yaitu komposisi media tanam dan volume media tanam. Komposisi media tanam terdiri atas lima taraf, yaitu (1) arang sekam : tanah (1:1), (2) cocopeat : tanah (1:1), (3) cocopeat : arang sekam (1:1), (4) arang sekam : cocopeat : tanah (1:1:1), dan (5) tanah (kontrol), sedangkan volume media tanam terdiri atas tiga taraf (10, 20, dan 30 L). Hasil penelitian menunjukkan bahwa tinggi, jumlah daun, volume akar dan kandungan P daun tanaman pamelo pada volume media tanam 30 L lebih besar dibandingkan dengan pada media 10 L, tetapi tidak berbeda nyata dengan pada media tanam 20 L, kecuali jumlah daun. Tinggi tanaman, volume akar dan kandungan N daun tanaman pamelo pada media arang sekam : tanah relatif lebih besar dibandingkan dengan pada media arang sekam : cocopeat. Media tanam arang sekam : cocopeat memiliki kandungan N, C, nisbah C/N, bahan organik, K2O dan nilai tukar kation lebih tinggi, tetapi kadar air, bobot isi dan bobot jenis lebih rendah dibandingkan dengan media tanam lain. Dengan demikian, komposisi media tanam yang paling sesuai untuk tanaman pamelo adalah arang sekam : tanah dan volume media tanam 20 L masih sesuai untuk tanaman pamelo hingga 24 MST (minggu setelah tanam). Kata kunci: arang sekam, cocopeat, kandungan N dan P daun, volume akar

Rootstock selection of physic nut (Jatropha curcas Linn.) on drought stress tolerance

Jatropha has the potential to be developed as biofuel, because of its high seed oil content. The seeds contain up to 35% oil which are convert into biodiesel easily. Superior plant materials had been produced through the composite selection (IP-1 to IP-3), were only able to express the potential yield on land that was in optimal conditions. On the contrary, land available for jatropha development, generally, in the form of dry land with limited water availability. Development of Jatropha in large scale in dryland require plant material with high productivity and able to adapt to drought conditions. In an effort to maintain the stability of jatropha production in dry land, it can be done through grafting technology by combining the advantages of prospective shoot section which has a high yield potential as a scion and rootstock candidates from plant material that is able to adapt to limited water availability. The activity had been carried out viz adaptability study of jatropha rootstock candidates associated with drought stress in glasshouse. The results of the study showed there were three jatropha rootstocks (IP-3M, Sulawesi 117 dan Jatim 045) those were tolerant to drought stress. Key word: Jatropha, drought stress, productivity

Model for Predicting and Classifying Durian Fruit Based on Maturity and Ripeness Using Neural Network

Abstract This study was aimed to develop the model to predict the maturity, ripeness and defects of durian based on its physical and chemical characteristics by using the neural network. The density and acoustic characteristics measurement was fed into the model as the inputs, which provided the levels of maturity and ripeness as the output. Data training were tested to models of neural network with various nodes in the hidden layer, i.e., 4, 6, 8, and 10 nodes. The results recommended the use of 6 nodes in the hidden layer that would provide the highest accuration of 100 % in classifying the durian based on its maturity and ripeness.

PENGARUH PEMBERIAN LUMPUR BUANGAN DARI PENGOLAHAN LIMBAH SINTESIS ANTIBIOTIKA DAN PUPUK KANDANG TERHADAP PERTUMBUHAN DAN PRODUKSI STEVIA (Stevia rebaudiana BERTONI M.)

The objective of the research was to investigate the effect of sewage application on growth and production of stevia, a sweetening alternative producing plant, as compared with manure application. Sewage is a by product of antibiotics processing of PT SBFI Sewage and manure application each consisted of 4 level, i.e. 0.0, 0.5, 1.0 and 1.5 kg per polybag. Sewage application has resulted in significant increase in tree high, leaf number, shoot number and root and shoot dry weight as compared with control. Manure application has resulted in significant increase in growth and production as compared with control. There was no interaction between sewage and manure application on all parameter observed