Ringkasan Perbanyakan tanaman teh [Camellia sinen­sis (L.) O. Kuntze] melalui stek tunas berdaun tunggal hanya dapat menghasilkan klon unggul dalam jumlah terbatas. Oleh sebab itu diperlukan metode alternatif dengan teknik kultur sel dan jaringan untuk perbanyakan klonal secara cepat. Dalam penelitian ini dikembangkan metode yang lebih efektif untuk regenerasi tanaman teh melalui embriogenesis somatik langsung. Massa pro­embriogenik dari eksplan kotiledon dihasilkan dengan frekuensi 56,7% dalam media MS padat setengah konsentrasi yang mengandung BAP 2 mg1L. Proliferasi, perkembangan, pendewasaan dan perkecambahan embrio somatik diperoleh dengan sistem perendaman sesaat (SPS) yang menggunakan media MS cair setengah konsen­trasi, yang diperkaya dengan zat pengatur tumbuh dengan berbagai konsentrasi. Proliferasi embrio meningkat 4,3 kali dalam media yang diberi BAP 2 mglL; perkembangan dan pendewasaannya meningkat dengan penambahan kinetin dan ABA masing-masing pada konsentrasi 0,1 mg1L yang 30% diantaranya berkecambah dan membentuk planlet tanpa penambahan zat pengatur tumbuh. Protokol SPS tersebut merupakan sistem in vitro yang berpotensi bagi proliferasi dan perkembang­an embrio somatik tanaman teh yang cepat dan sinkron dari kultur kotiledon, serta regenerasinya menjadi planlet tanpa melalui fase kalus.Summary Tea propagation by single-leaf bud cuttings has limited applications for rapid dissemination of planting materials from new elite clones. An alternative method for rapid cloning by cell and tissue culture technique is necessary. In this study we have established an improved method for tea [Camellia sinensis (L.) O. Kuntze] plant regenera­tion via direct somatic embryogenesis. Clumps of proembryogenic masses were initiated at a fre­quency of 56.7% from cotyledonary slices cul­tured on a half-strength MS agar-gelled medium supplemented with 2 mg/L BAP. Proliferation, development, maturation and germination of so­matic embryos were achieved using the temporary immersion system (TIS) provided with half­strength MS liquid media supplemented with varying concentrations of growth regulators. Em­bryo proliferation increased by 4.3-fold in me­dium provided with 2 mg/L BAP; their develop­ment and maturation were enhanced by the presence of both kinetin and ABA at 0.1 mg/L each. Germination and plant recovery were achieved at a frequency of about 30% without the use of growth regulators. The TIS protocol des­cribed above represents an in vitro system poten­tial for rapid proliferation and synchronized development of tea somatic embryos from cotyledon cultures, and their regeneration into plantlets without an intervening callus phase.

Perennial sowthistle (Sonchus arvensis L.) is known as a medicinal plant but rarely cultivated, perennial sowthistle grows wild. Characterization is needed to determine the variation and relationship of perennial sowthistle in situ. Differences environment affect plant growth and bioactive content. Phenotype characterization of plant species is the basis for selection and improvement of properties. The purpose of this study was to evaluate the variation of agrophysiological characters and to analyze the relationship of 10 accessions of sowthistle based on agro-physiological characters. The experiment was conducted in October 2015 to February 2016. Descriptive variation characteristic of agrophysiological, correlation coefficient, principal component analysis (PCA) and cluster analysis (CA) were used to evaluate the phenotypic variability. The PCA and CA generated similar results. The first five principal component axes explained 91.7% of the total variation with PC1 (43.7%) and PC2 (22.9%). The CA showed that the degree of intraspecific similarity was 52.04%. Three clusters were formed among the 10 accessions especially with the separation of accessions that were collected from similar environments.Keywords: cluster, similarity, principal component, Sonchus arvensis L.ABSTRAKTempuyung dikenal sebagai tanaman obat tradisional namun belum banyak dibudidayakan, tempuyung tumbuh liar di alam. Perbedaan lingkungan tumbuh aksesi berpengaruh terhadap pertumbuhan dan kadar bioaktif tempuyung. Karakterisasi diperlukan untuk mengetahui keragaman dan kekerabatan tempuyung in situ. Karakterisasi fenotip spesies tanaman merupakan dasar untuk seleksi dan perbaikan sifat. Penelitian ini bertujuan mengevaluasi keragaman karakter agro-fisiologi, dan menganalisis kedekatan hubungan antar 10 aksesi tempuyung in situ berdasarkan karakter agro-fisiologi. Penelitian dilaksanakan pada bulan Oktober 2015 sampai Februari 2016. Deskripsi keragaan karakter agro-fisiologi, koefisien korelasi, analisis gerombol dan analisis komponen utama digunakan untuk mengevaluasi keragaman fenotip. Aksesi Tawangmangu menunjukkan keragaan tertinggi pada karakter jumlah daun, lebar daun, diameter batang, bobot basah daun, bobot kering daun, total bobot basah, total bobot kering, tebal daun dan total flavonoid. Analisis gerombol (AG) dan analisis komponen utama (AKU) memberikan hasil yang mirip. Lima sumbu komponen utama menjelaskan 91.7% total keragaman dengan KU 1 (43.7%) dan KU 2 (22.9%). AG menunjukkan tingkat kemiripan sebesar 52.04%. Tiga kelompok terbentuk dari 10 aksesi yang dikoleksi yang diduga berdasarkan kesamaan lingkungan tumbuh.Kata kunci: gerombol, kemiripan, komponen utama, Sonchus arvensis L.

Tempuyung (Sonchus arvensis L.) is known in Indonesia as traditional medicine. This study was conducted to observe diseases that attack tempuyung in organic cultivation. Ten accessions of sowthistle were collected from Dramaga, Cibadak, Cicurug, Lembang, Matesih, Sekipan, Tawangmangu, Batu, Banjararum, and Sumbersekar, with altitudes between 186-1280 m above sea level and rainfall of 988-2573 mm. The research was carried out in the organic experimental field of Cikarawang, IPB, Bogor, with a geographical location of 6o30' - 6o45' SL and 106o30'-106o45´ EL and an altitude of 190 m above sea level. The research location is a lowland with 1618 mm of rainfall during the study. Pest identification was carried out in the Plant Clinic laboratory of the Plant Protection Department of IPB. Disease identification was carried out by taking symptomatic plants, then isolated and grown in PDA media and then identified. The results showed that the disease that attacked the sowthistle in this experiment was caused by the bacterium Pseudomonas sp and fungi Fusarium sp. The disease attack rate ranges from 32 to 60%. Disease attacks were controlled by removing the affected plants and then spraying with turmeric solution in a ratio of 1: 10. Pests that attacked sowthistle were snails, grasshoppers, fruit borer caterpillars, and panicle-sucking insects.