THE EFFECT OF PICLORAM AND LIGHT ON SOMATIC EMBRYOGENESIS REGENERATION OF PINEAPPLE

Smooth Cayenne is the largest pineapple type cultivated in Indonesia, but its vegetative planting materials for mass propagation are limited. Somatic embryogenesis is a potential method to be applied. The aim of this study was to investigate the somatic embryogenesis regeneration under the effect of picloram and light. Callus formation was induced by picloram (21, 41 and 62 μM) added with 9 μM thidiazuron. The calli were transferred onto MS or Bac medium  enriched with N-organic compounds with or without addition of 21 μM picloram under dark or light condition. The compact calli were subcultured onto MS medium supplemented with 4.65 μM kinetin, while the friable calli were  transferred onto BIG medium (modified MS + 1.1 μM benzyl adenine + 0.9 μM indole butyric acid + 0.09 μM giberelic acid) or B medium (MS + 0.018 mM benzyl adenine). The results showed that the events of somatic embryogenesis were started from cell polarization, asymmetrical division, proembryo formation as  embryogenic tissues and friable embryogenic tissues, and embryo development. The best treatment for callus induction was 21 μM picloram. The addition of 21 μM picloram on N-organic enriched medium and the use of light condition  proliferated embryogenic calli. The N-organic enriched Bac medium and light condition yielded the highest number of mature somatic embryos (17 embryos perexplant in 2 months). The B medium was better than BIG medium to develop  somatic embryos from friable embryogenic tissues. The somatic embryogenesis method presented is potential for pineapple mass propagation and artificial seedproduction.Abstrak Bahasa IndonesiaSmooth Cayenne merupakan kultivar nenas yang banyak dibudidayakan di  Indonesia, namun ketersediaan benih untuk perbanyakan massal masih terbatas. Embriogenesis somatikadalah metode yang potensial untuk produksi bibit secara massal. Tujuan penelitian adalah untuk mempelajari pengaruh pikloram dan pencahayaan terhadap regenerasi embriogenesis somatik nenas. Kalus diinduksi menggunakan pikloram (21, 41, dan 62 μM) dan penambahan thidiazuron 9 μM. Selanjutnya, kalus dipindahkan ke media MS atau Bac yang diperkaya dengansenyawa N-organik dengan atau tanpa penambahan pikloram 21 μM dalam kondisi gelap atau dengan pencahayaan. Kalus kompak disubkultur pada media MS yang mengandung kinetin 4,65 μM, sedangkan kalus remah dipindahkan ke media BIG (MS modifikasi + bensil adenin 1.1 μM + indole butyric acid 0,9 μM + giberelic acid 0,09 μM) atau media B (MS + bensil adenin 0,018 μM). Hasil penelitian  menunjukkan bahwa tahapan embriogenesis somatik diawali dengan polarisasi sel, pembelahan asimetris, pembentukan proembrio sebagai jaringan embriogenik danjaringan embriogenik remah, serta perkembangan embrio. Perlakuan terbaik untuk induksi kalus adalah pikloram 21 μM. Penambahan pikloram 21 μM pada media yang diperkaya dengan senyawa N-organik mampu meningkatkan jumlah kalusembriogenik. Media Bac yang diperkaya senyawa N-organik dan kondisi pencahayaan menghasilkan jumlah embrio somatik dewasa terbanyak (17 embrio per eksplan dalam 2 bulan). Media B lebih baik daripada media BIG untuk regenerasi embrio somatik dari jaringan embriogenik remah. Metode embriogenesis somatik yang dihasilkan dari penelitian ini berpotensi diterapkan untukperbanyakan massal dan produksi benih nenas

Functional Classification of Skinning Injury Responsive Genes in Storage Roots of Sweetpotato

Skinning injury in sweetpotato due to loss of skin or periderm which occurred during harvest is inevitable and account for financial loss due to dehydration, pests, and pathogens. Hence, studies on gene expression changed due to skinning injury can provide important information about this protective tissue and for improving the life of storage roots. New candidate genes involved in skinning injury were isolated with an Annealing Control Primer (ACP). Using 20 ACP primers, a total of 103 differentially expressed genes (DEGs) were retrieved. In this study, the functional annotation of these selected 15 up-regulated DEGs (10 contigs and 5 singletons) were characterized. The results showed that these 15 “DEG-unigenes” are mainly associated with defense and stress responses, regulation and signaling, protein synthesis and fate, and metabolism may play an important role in the primary responses to skinning injury in storage roots of sweetpotato. This study showed the importance of defense and stress responses genes to the formation of wound periderm. Furthermore, this results can be used for better understanding of the molecular mechanism of skinning/mechanical injury-related genes in the storage roots of sweetpotato as well as to all stems, fruits, and roots of all plants. Keywords: differentially expressed gene, gene function, Ipomoea batatas, woundin

Induksi Ginogenesis melalui Kultur Multi Ovule Slice dan Kultur Ovary Slice Dianthus chinensis

Callus induction was studied in five genotypes of Dianthus chinensis using 2.4 D and NAA. Calluses can be obtainedfrom unfertilized ovule culture and ovary culture. The aim of the research was to study gynogenic potential and responseof Dianthus chinensis through ovule slice and ovary slice culture for obtaining haploid plants. Five genotypes of Dianthuschinensis and five media were used in ovule slice culture and two genotypes and three medium were used in ovary culture.Flower buds in the 7th stage were incubated for the purpose of dark pre-treatment at 4 oC for one day. Ovules and ovaries wereisolated and cultured in induction medium. Cultures were incubated for the purpose of dark pre-treatment at 4 oC for seven days, followed by 25 oC light incubation. The result showed that 2.4D was better than NAA in inducing callus. Percentage of regenerated calluses were produced in V11, V13 and V15 genotypes in M7 medium (MS + 2 mg L-1 2.4D + 1 mg L-1 BAP + 30 g L-1 sucrose and M10 medium (MS + 1 mg L-1 2.4D + 1 mg L-1 BAP + 20 g L-1 sucrose). All calluses originated from ovule and ovary cultures flowered prematurely. Double haploid (V11-34) were obtained from ovule slice culture based on PER (peroksidase) and EST (esterase) isoenzym marker.Keywords: ovule slice culture, ovary slice culture, callus, Dianthus sp., haploi

Gamma Irradiation and In vitro Selection Could Increase Drought Tolerance in Sugarcane

Drought is one of the problems that decrease sugarcane productivity. Therefore it needs to develop a new drought tolerant sugarcane variety. The objectives of this research were to evaluate the response of gamma irradiated calli and drought tolerant of putative mutants through in vitro and in vivo selection. Kidang Kencana (KK) variety was used as mother plant in this study. It has high productivity but susceptible to drought stress. Embryogenic calli were induced on MS media supplemented with