49 Sumadi, dkk. : Pengaruh pemberian zat retardan terhadap pertumbuhan dan hasil ubi pada dua kultivar kentang (Solanum tuberosum L.) di dataran medium Sumadi • E. Suminar • Murgayanti • A. Nuraini Pengaruh pemberian zat retardan terhadap pertumbuhan dan hasil ubi pada dua kultivar kentang (Solanum tuberosum L.) di dataran mediumEffect of retardants substances on growth and seed tuber yield productivty of two potato cultivars (Solanum tuberosum L.) at medium land Abstract The objective of this study was to obtain information on potato varieties and the type and concentration of retardants that can support growth, development, quantity and quality of potato seeds in medium land. The research method used was the split plot design, the main plot was the potato variety, Nadia and Granola and the subplot wasthe type and concentration of the used retardants: paklobutrazol (0, 40; 120 mgL -1 ) and coumarin(45; 90;135 mgL -1 ). The result showed that kind of variety and retardants substance affectedon growth and development of potato seed. There are have an interaction effect between variety and substance retardants for the weight of potatoes tuber per plant, butno interaction for plant height, chlorophyll content, number of tuber per plant, tuber weight per plot and the percentage of potatoes size tuber were produced. The application of retardan Nadia Varieties produced tuber weight per plant higher than the granola variety,whereas granola variety produced tuber sizes S and M classes higher than Nadia variety.Sari Tujuan dari kegiatan penelitian ini adalah untuk mendapatkan informasi mengenai kultivar kentang dan jenis serta konsentrasi zat retardan yang dapat mendukung pertumbuhan dan perkembangan serta kuantitas dan kualitas hasil ubi bibit kentang di dataran medium. Metode penelitian yang digunakan adalah

Tujuan dari kegiatan penelitian ini adalah untuk mendapatkan informasi mengenai kulti-var kentang dan jenis serta konsentrasi zat retardan yang dapat mendukung pertumbuhan dan perkembangan serta kuantitas dan kualitas hasil ubi bibit kentang di dataran medium. Metode penelitian yang digunakan adalah Rancangan Petak terpisah. Perlakuan terdiri dari petak utama yaitu kultivar yaitu kultivar Nadia dan Granola, dan anak petak yaitu jenis dan konsentrasi zat retardan dengan penggunaan paklobutrazol ( 0; 40; 120 mg L-1 ) atau coumarin (45; 90; 135 mg L-1). Hasil percobaan menun-jukkan bahwa jenis kultivar dan zat retardan berpengaruh terhadap pertumbuhan dan per-kembangan bibit kentang. Terjadi interaksi pada peubah bobot ubi per tanaman, sedangkan peubah tinggi tanaman, kandungan klorofil, jumlah ubi per tanaman, bobot ubi per petak dan persentase jumlah ubi kentang per tanaman berdasarkan pengkelasan ubi bibit tidak terjadi interaksi antara kultivar dan zat retardan.  Penggunaan zat retardan pada kultivar Nadia menghasilkan bobot ubi per tanaman lebih tinggi daripada kultivar Granola sedangkan untuk kelas ubi ukuran S dan M dihasilkan lebih tinggi pada kultivar Granola daripada kultivar Nadia. Kata kunci : Kentang ∙ Ubi ∙ Dataran medium ∙ Zat retardan

Respons klon ubi jalar (Ipomoea batatas L.) var. Awachy-1 dan var. Biang terhadap aplikasi paclobutrazolResponse of sweetpotato clones (Ipomoea batatas L.) var. Awachy-1 and var. Biang to paclobutrazole application Abstract. Paclobutrazol is one type of plant growth regulators that can be used to regulate plant growth with the aim of maintaining the balance of vegetative and generative growth. Each plant genotype would produce a different responses to paclobutrazol. The aimed of this study was to determine the interaction between the concentration of paclobutrazol and two sweet potato clones and to determined the best concentration of paclobutrazol for yield of two sweet potato clones. The experiment was conducted from February to June 2017 at Ciparanje Experimental Station, Faculty of Agriculture, Padjadjaran University, Jatinangor, Sumedang Regency, West Java on 750 m above sea level. Type of rainfall of the experimental area was classified as C type according to Schmidt and Ferguson. The experiment design used Factorial Randomized Block Design that consisted of two factors and repeated four times. The first factor was sweet potato clone (Biang and Awachy 1) and second factor was the concentration of paclobutrazol (0, 50, 100, 150 ppm). The results showed that the number of tubers in Biang produced higher than Awachy 1, and the treatment of paclobutrazol with concentration of 50 ppm had the best yield (weigth of tubers per plant).

AbstrakSaat ini, perbanyakan rami menggunakan rizoma sebagai bahan tanamnya, tetapi dalam produksinya membutuhkan waktu yang lama dan sebagai bahan tanam umur simpannya singkat. Kultur jaringan merupakan salah satu teknologi untuk mendapatkan bahan tanam yang seragam dan sehat dalam waktu yang singkat. Tujuan dilakukannya penelitian ini adalah untuk mengetahui pengaruh konsentrasi BAP terhadap pertumbuhan tunas aksilar pada rami klon lokal Wonosobo dan konsentrasi mana yang memberikan pengaruh terbaik. Percobaan dilakukan di Laboratorium Kultur Jaringan, Teknologi Benih, Fakultas Pertanian, Universitas Padjadjaran. Nodus batang dari rami klon lokal Wonosobo diklturkan pada media MS dengan penambahan berbagai konsentrasi BAP selama 8 minggu dan diamati pertumbuhan dan perkembangannya. Desain penelitian yang digunakan adalah Rancangan Acak Lengkap (RAL) dengan 6 perlakuan yang diulang sebanyak tiga kali. Adapun perlakuannya adalah kontrol (tanpa penambahan BAP), BAP 0,5 mg/L, BAP 1,0 mg/L, BAP 1,5 mg/L, BAP 2,0 mg/L, dan BAP 3,0 mg/L. Hasil percobaan menunjukkan penambahan sitokinin berpengaruh terhadap pertumbuhan tunas aksilar rami klon lokal Wonosobo. Penambahan 0,5 mg/L berpotensi memberikan pengaruh terbaik terhadap pertumbuhan tunas aksilar rami klon lokal Wonosobo dilihat dari waktu muncul tunas, jumlah tunas, jumlah daun, dan tinggi plantlet. Kata Kunci: Benzylaminopurine (BAP) ∙ Rami ∙ Tunas aksilar AbstractCurrently, ramie propagation used the rhizome as the planting material. However, it took long time to produce and the longevity of rhizome as planting material is short. Therefore, another technology approach is needed. Tissue culture is one of alternative technologies that could to produce uniform and healthy planting material within short time. The objective of this research was to determine the effect of BAP concentration on the axillary bud growth of rami local clone of Wonosobo and also determine which concentration gives the best effect. The research was conducted at The Tissue Culture Laboratory of Seed Technology, Faculty of Agriculture, Universitas Padjadjaran. Nodes of ramie local clone of Wonosobo were cultured for 8 weeks on Murashige & Skoog (MS) medium added with various concentrations of BAP and then observed growth and development. The research design was Completely Randomize Design (RCD) with 6 treatments in terms of BAP concentrations and 3 replications. The treatment was ,control (without BAP); BAP 0,5 mg/L, BAP 1,0 mg/L, BAP 1,5 mg/L, BAP 2,0 mg/L, and BAP 3,0 mg/L. The result showed that there was different effect on axillary bud growth. The treatment of MS medium added with 0,5 mg/L BAP potentially showed as the best effect for bud appearance, number of shoots, number of leaves, and plantlet’s length.Keywords: Benzylaminopurine (BAP) ∙ Ramie ∙ Axillary bud

Studi pendahuluan regenerasi eksplan teh sebagai upaya percepatan penyediaan bibit unggul secara in vitroSari. Pembiakan generatif tanaman teh yang dilakukan dengan biji, sementara secara vegetatif dengan setek tunas yang mempunyai kelemahan, antara lain jumlah bibit yang dihasilkan terbatas, perlu waktu lama untuk menyeleksi pohon induk, dan bibit yang dihasilkan kurang optimal dalam penyerapan air dan unsur hara karena perakarannya dangkal sehingga kurang toleran terhadap kekeringan. Kultur jaringan menjadi salah satu alternatif dalam perbanyakan teh memperoleh klon teh unggul, seperti klon Seri Gambung 1-11, dalam jumlah banyak dan sifatnya yang seragam. Penelitian pendahuluan ini dilaksanakan di Laboratorium Kultur Jaringan Departemen Budidaya Pertanian Fakultas Pertanian UNPAD, mulai bulan Juni hingga Desember 2021. Penelitian terdiri dari dua tahap, yaitu (i) metode deskriptif untuk menginduksi eksplan organ teh (pucuk + ruas batang serta daun), dan (ii) metode eksperimen dengan menguji eksplan yang ditumbuhkan pada berbagai media. Metode percobaan yang digunakan untuk penelitian ke-2 adalah rancangan acak lengkap (RAL) dengan 6 kombinasi perlakuan Benzyl Amino Purine (BAP) (0 dan 0,5 ppm) dan 2,4-D (0,05; 0,1; dan 0,2 ppm). Hasil pengamatan pendahuluan menunjukkan masih banyak eksplan yang mengalami kematian, namun beberapa eksplan potongan daun menunjukkan respon yang baik dengan mampu membentuk kalus berwarna hijau. Kombinasi 0,5 ppm BAP + 0,05 ppm 2,4-D memberikan pengaruh lebih baik terhadap bobot kalus, sedangkan kombinasi 0,5 ppm BAP + 0,2 ppm 2,4D memberikan pengaruh baik terhadap diameter kalus. Kata kunci : Eksplan teh • In vitro • Klon unggul Preliminary study of tea explant regeneration as an effort to accelerate the supply of superior seeds by in vitroAbstract. Generative propagation of tea plants is done by seed, while the vegetative method is by shoot cuttings which have weaknesses, including the limited number of seedlings produced, it takes a long time to select the mother tree, and the resulting seedlings are not optimal in absorbing water and nutrients because their roots are shallow making it less tolerant of drought. Tissue culture is an alternative in tea propagation to obtain superior tea clones, such as the Gambung Series 1-11 clones, in large quantities and with uniform characteristics. This preliminary research was carried out at the Tissue Culture Laboratory of the Department of Agronomy, Faculty of Agriculture, UNPAD, from June to December 2021. The research consisted of two stages, namely (i) a descriptive method to induce tea organ explants (shoots + stem segments and leaves), and (ii) an experimental method by testing explants grown on various media. The experimental method used for the second study was a completely randomized design (CRD) with 6 treatment combinations of Benzyl Amino Purine (BAP) (0 and 0.5 ppm) and 2.4 D (0.05; 0.1; and 0 .2 ppm). Preliminary observations showed that there were still many death explants observed, however, some explants in form of cut leaves ...