Yellow cosmos (Cosmos sulphureus Cav.) is a specific flowering plant and considered a suitable genetic engineering model. Agrobacterium-mediated plant transformation is commonly used for plant genetic engineering. Floral dip transformation is one of the plant genetic transformation methods, and it involves dipping flower buds into an Agrobacterium suspension. Studies on floral dip transformation of yellow cosmos have never been reported. Therefore, an efficient method in plant genetic engineering must be established. This study developed an effective and efficient floral dip transformation method for yellow cosmos.

Keragaman Morfologi dan Molekuler Empat Kelompok Kultivar Jagung ( Zea mays L.)

Irsyadi MB, Sawitri WD, Purwantoro A. 2022. Molecular and phenotypic characteristics of T1 transgenic yellow cosmos (Cosmos sulphureus) carrying neomycin phosphotransferase II gene. Biodiversitas 23: 6097-6105. Yellow cosmos (Cosmos sulphureus) is a tropical ornamental flower that contains secondary metabolites useful fornatural pesticide application. Plant genetic transformation is one genetic engineering method used to increase secondary metabolite accumulation. However, published reports on this issue have yet to be made available. This is the first report of genetic transformation in transgenic yellow cosmos using neomycin phosphotransferase II (nptII) encoding gene. This study aimed to determine the efficiency transformation and phenotypic character of the T1 yellow cosmos transgenic nptII. This genetic transformation was carried out by the floral dip method mediated with Agrobacterium tumefaciens and characterized based on quantitative and qualitative observations, as well as a cluster analysis of transgenic plants. The T1 transgenic yellow cosmos was confirmed using PCR with a transformation efficiency of 73.33% based on the total plants resistant to Kanamycin and 10.57% based on the total seeds transformed. The presence of the nptII encoding gene was shown in transgenic plant samples with a size of 550 bp. In general, the introduction of the nptII gene generated no novel traits except the resistance to the kanamycin antibiotic. However, there was a decrease and increase in the number of stomata and the size of stomata in transgenic plants, respectively. In addition, there was a change in the type of ray floret to a mixture of ligulate and tubular, indicating that the nptII gene affected the phenotype of yellow cosmos. The result revealed that the nptII gene was inserted fairly randomly into the plant genome.

Chili (Capsicum annuum L.) is a self-pollinated crop, with natural cross-pollination occurring below 4%–5%. It intends to have low heterosis. Developing cross-pollination in chili currently receives much attention to achieve diversity in trait improvement. Double-crossing becomes one of the alternatives to achieving this goal. In this study, three different parental chili genotypes (K, B, and T) gained crossing, with four populations (S2 K, F3 KB, F2 BTKB, and F2 KBBT) developed. Using 11 selected sequence-related amplified polymorphism (SRAP) combination markers that target Open Reading Frame (ORF) regions assessed molecular diversity in these chili populations. Results revealed the possibility of identifying diversity using SRAP markers based on primer profile information. The iMEC analysis showed high values of PIC (0.3381), discriminant power (0.882), and mean polymorphic value (97.88%). The highest similarity emerged between the populations BTKB and KBBT as the reciprocal. Then, the smallest similarity appeared between K and the double cross. Compared with the self-pollinated genotype, SRAP primers discovered that double crosses provided more variation based on Shannon’s index (I) and percentage of polymorphic loci (PPL). The genetic distance denotes maternal inheritance or extraneous involvement in progeny. However, multiple-parent hybridization authenticated the boost in genetic diversity.

Dendrobium hybrid section Spatulata is widely cultivated in Indonesia due to its ease of cultivation, high economic value and adaptability, also extended flower shelf life. Various attempts to meet the rising market demand for Dendrobium hybrid section Spatulata, including the development of new varieties with unique flower traits such as flower color, a longer and bigger horn, and disease resistance. In this study, we conducted a breeding program aimed at developing a new cultivar of Dendrobium hybrid section Spatulata (antelope orchids) through interspecific hybridization. The study aimed to investigate the genetic variation and genomic constitution of the eight hybrids and their corresponding parental lines that resulted from interspecific hybridization using sequence‐related amplified polymorphism (SRAP) marker. Six species of Dendrobium section Spatulata i.e., Dendrobium Sri Mulyani, D. Cochliodes, D. strepsiceros, D. stratiotes, D. Alice Noda, D. helix, and several hybrids of antelope orchids derived from three hybridizations including D. Sri Mulyani × D. cochliodes, D. stratiotes × D. strepsiceros, and D. Alice Noda × D. helix, respectively, were subjected into SRAP markers for genotyping analysis. Dendrobium hybrid section Spatulata hybrids produced by interspecific hybridization were genuine hybrids with substantial genetic variability based on flower morphology, including labellum shapes and color intensities, as well as curly horn shapes and color intensities. The SRAP marker, which was used to genotype the hybrid and parental lines, exhibited a significant degree of polymorphism, and might be used to distinguish each accession. It produced a unique DNA amplicon that ranged from 180 to 530 bp and inherited a certain progeny line. The unweighted pair group mean average (UPGMA) dendrogram and Principal Coordinate Analysis (PCoA) biplot showed that all the hybrids were grouped into three major clusters according to their corresponding parental lines based on their genetic background and ge‐ nomic constitution. These findings are critical for the genetic improvement of the Antelope orchid to develop novel varieties.

Generally, the standard procedure for karyotype analysis of shallot is sorted by chromosome sizes. Therefore, the identification of homologous chromosomes is difficult without using a specific probe. Nucleolus Organizing Regions (NORs) can be used as a probe for precise identification of homologous chromosomes. However, the use of NORs for plant karyotyping in Indonesia is poorly investigated. In this study, shallot chromosomes were prepared using modified Carnoy’s solution II, fixed in Carnoy’s solution, and stained by using aceto-carmine and AgNO3 for detecting NORs. Chromosome images were analyzed by CHIAS IV. One locus NOR bearing chromosome pair was detected at metaphase and interphase, and it was located at short arms of subtelomeric chromosome number 6. NORs can be used as a probe for precise identification of homologous chromosomes in shallot. Therefore, this technique has the potential to be applied on species closely related to shallot and on other plant species.Keywords: AgNO3, chromosome condensation, NORs, shallot chromosome, shallot karyotype ABSTRAKProsedur kariotipe untuk bawang merah umumnya masih disusun berdasarkan ukuran kromosom, sehingga diperlukan suatu penanda yang dapat mengidentifikasi kromosom homolog secara presisi. Identifikasi kromosom homolog secara presisi menggunakan suatu penanda, khususnya deteksi Nucleolus Organizing Regions (NORs), yang di Indonesia masih jarang dilakukan. Penelitian ini bertujuan untuk membuat kariotipe dan mengidentifikasi kromosom homolog bawang merah melalui deteksi NORs menggunakan metode pewarnaan AgNO3. Proses fiksasi akar dilakukan dengan menggunakan modifikasi larutan Carnoy II, lalu difiksasi dengan larutan Carnoy, dan kromosom diwarnai dengan aceto-carmine dan larutan AgNO3 untuk mendeteksi NORs. Selanjutnya, citra kromosom dianalisis menggunakan CHIAS IV. Hasil penelitian menunjukkan bahwa terdapat sepasang NORs yang terdeteksi pada fase metafase dan interfase yang terletak pada bagian lengan pendek di kromosom subtelosentrik nomor 6. Hasil dari penelitian ini dapat dijadikan sebagai dasar di bidang sitogenetika bawang merah untuk mengidentifikasi kromosom homolog secara presisi menggunakan penanda NOR. Oleh karenanya, teknik ini dapat diaplikasikan pada spesies yang berdekatan dengan bawang merah dan komoditas tanaman lainnya.Kata Kunci: AgNO3, kariotipe bawang, kondensasi kromosom, kromosom bawang, NORs