ence darmo - Profile on Academia.edu (original) (raw)

Papers by ence darmo

An Efficient Anther Culture on Double-Layered Media to Produce Doubled Haploid Plants of Pepper (Capsicum annuum)

Methods in molecular biology, 2021

An efficient anther culture on double-layered media to produce doubled haploid (DH) plants in pep... more An efficient anther culture on double-layered media to produce doubled haploid (DH) plants in pepper (Capsicum annuum) was clearly shown to outperformed other techniques such as anther culture on solid medium and direct isolated microspore culture on liquid medium. It was even used for DH production in a cayenne type of hot pepper which was previously known as less responsive or even more recalcitrant to androgenesis than sweet bell pepper. Indeed, anther culture on double-layered media has been routinely used to produce DH plants on broad genotypes of C. annuum as parental candidates to develop hybrid varieties. The step-by-step protocol of pepper anther culture on double-layered media, we hereby present in detail, includes the growth of donor plants, the use of flower buds as anther source, flower bud disinfection, anther isolation, anther culture and incubation processes, embryo germination and plant acclimatization process, and transplanting of plants to the soil-compost medium ...

Plant Cell Reports, 2005

Various systems of anther and microspore cultures were studied to establish an efficient doubled ... more Various systems of anther and microspore cultures were studied to establish an efficient doubled haploid production method for Indonesian hot pepper (Capsicum annuum L.). A shed-microspore culture protocol was developed which outperformed all the previously reported methods of haploid production in pepper. The critical factors of the protocol are: selection of flower buds with more than 50% late unicellular microspores, a 1 day 4°C pretreatment of the buds, followed by culture of the anthers in double-layer medium system for 1 week at 9°C and thereafter at 28°C in continuous darkness. The medium contained Nitsch components and 2% maltose, with 1% activated charcoal in the solid under layer and 2.5 μM zeatin and 5 μM indole-3-acetic acid in the liquid upper layer. All the ten genotypes of hot pepper tested, responded to this protocol. The best genotypes produced four to seven plants per original flower bud. This protocol can be used as a potential tool for producing doubled haploid palnt sfor hot pepper breeding.

HAYATI Journal of Biosciences, 2017

Falcataria moluccana is important for reforestation and afforestation in Indonesia. However, epid... more Falcataria moluccana is important for reforestation and afforestation in Indonesia. However, epidemic of gall rust disease in F. moluccana plantations decreases its productivity. Genetic engineering is an alternative solution to against gall rust disease. Somatic embryogenesis is an efficient in vitro plant regeneration for successful plant improvement through genetic engineering. The objective of this study was to investigate the effect of thidiazuron and light treatments on the induction of somatic embryogenesis of F. moluccana. The effects of thidiazuron concentration (5, 10 or 15 mM) and light (continuous light, 7 days of dark followed by light, or continuous dark) on the induction of somatic embryogenesis in leaf explants were assessed. The highest production of somatic embryos was obtained in 5 mM thidiazuron and dark treatments for 7 days followed by light in Murashige and Skoog medium supplemented with 1.2 g/ L proline. Histological analysis in globular and cotyledon stages confirmed that cells had progressed to secondary somatic embryogenesis. This research needs more improvements to become a successful and efficient somatic embryogenesis method and as a potential method for successful plant improvement through genetic engineering in F. moluccana.

Prosedur yang efisien untuk memproduksi tanaman ha~loid ganda (HG) beberapa genotipe cabai Indone... more Prosedur yang efisien untuk memproduksi tanaman ha~loid ganda (HG) beberapa genotipe cabai Indonesia melalui k • antera dalam sistem media dua-lapis telah berhasil drlakukan d1 Belanda melalur proyek ke!Jasama lndonesra-Bela (BIORIN). lmplementasi prosedur ini pada kondisi lokal di Bogar mendapat hambatan, terutama masalah kontamrnasr pa.::. kultur dan kondisi lingkungan pertumbuhan tanaman sumber eksplan yang berbeda. Kntena kuncup bunga sumber eks pada HG Galaxy untuk fase perkembangan mikrospora lebih dari 50% pada fase akhir berinti tunggal adalah ketika pesama tinggi sampai sedikit lebih dari sepal , dan dicirikan dari munculnya warna unggu pada UJUng antera sampar seteng dari panjang antera. Penanganan masalah kontaminasi kultur in vitro berhasil dilakukan dengan menambahan kombrna antibiotik Rifampisin 10 mg/1 dan Timentin 400 gil dalam medium carr. Prosedur hasrl_ adaptasr 101 telah b~rhasrl drcoba. untuk beberapa ku ltivar cabai lokal , misalnya Tanjung. Pengecambahan dan akhmatrsasr berhasrl drlakukan d e~ tahapan mengecambahkan embrio lengkap pada media-agar Y, MS dalam botol kultur, akhmatrsasr ddakukan _ pa campuran media tanah :kasting:arang sekam (1 :1:1) dengan pengaturan kelembaban. Pro~edur yang telah dradaptasr_ pa• kondisi lokal ini akan menjadi dasar untuk memproduksi secara cepat tanaman HG cabar kultrvar lokal, untuk selanjutr dilakukan persilangan dialel sebagai upaya un tuk memperoleh beberapa kandidat varietas hibrida cabai unggul berbas: kultivar lokal.

Tinjauan ulang pengembangan teknologi haploid cabai dan prospeknya untuk percepatan penelitian genetika dan pemuliaan tanaman

Gain-of-function studies have shown that ectopic expression of the BABY BOOM (BBM) AP2/ ERF domai... more Gain-of-function studies have shown that ectopic expression of the BABY BOOM (BBM) AP2/ ERF domain transcription factor is suYcient to induce spontaneous somatic embryogenesis in Arabidopsis (Arabidopsis thaliana (L.) Heynh) and Brassica napus (B. napus L.) seedlings. Here we examined the eVect of ectopic BBM expression on the development and regenerative capacity of tobacco (Nicotiana tabacum L.) through heterologous expression of Arabidopsis and B. napus BBM genes. 35S::BBM tobacco lines exhibited a number of the phenotypes previously observed in 35S::BBM Arabidopsis and B. napus transgenics, including callus formation, leaf rumpling, and sterility, but they did not undergo spontaneous somatic embryogenesis. 35S::BBM plants with severe ectopic expression phenotypes could not be assessed for enhanced regeneration at the seedling stage due to complete male and female sterility of the primary transformants, therefore fertile BBM ectopic expression lines with strong misexpression phenotypes were generated by expressing a steroid-inducible, posttranslationally controlled BBM fusion protein (BBM:GR) under the control of a 35S promoter. These lines exhibited spontaneous shoot and root formation, while somatic embryogenesis could be induced from in-vitro germinated seedling hypocotyls cultured on media supplemented with cytokinin. Together these results suggest that ectopic BBM expression in transgenic tobacco also activates cell proliferation pathways, but diVerences exist between Arabidopsis/B. napus and N. tabacum with respect to their competence to respond to the BBM signalling molecule.

Refinement of shed-microspore culture protocol to increase normal embryos production in hot pepper (Capsicum annuum L.)

Scientia Horticulturae, 2011

Abstract A low percentage of normal-looking embryos (20%) is still a problem in an efficient shed... more Abstract A low percentage of normal-looking embryos (20%) is still a problem in an efficient shed-microspore culture of hot pepper (Capsicum annuum L.) and it is more a serious problem in other androgenesic culture systems of pepper. Therefore, several factors were investigated to refine the protocol in order to increase the percentage of normal-looking embryos. The most important factors which improved the protocol and resulted in a significantly higher percentage of normal-looking embryos produces (>50%), were delayed enrichment of the liquid upper layer medium with 2.5 μM Zeatin and 5 μM IAA, and reduced incubation temperature from 28 °C to 21 °C, both after 3 weeks of culture. Addition of 1% activated charcoal in the solid lower layer of the medium enhanced the total embryo yield only, while an application of abscisic acid and increased osmolality medium had a detrimental effect on embryo production. The use of doubled haploid lines as anther donor plants has clearly decreased the variability and improved the statistical analysis of treatment effects. A higher percentage of normal embryos are produced with this refined protocol, and is therefore more suitable for implementation in the breeding programs of hot pepper.

Successful development of a shed-microspore culture protocol for doubled haploid production in Indonesian hot pepper ( Capsicum annuum L

Plant Cell Reports, 2006

Various systems of anther and microspore cultures were studied to establish an efficient doubled ... more Various systems of anther and microspore cultures were studied to establish an efficient doubled haploid production method for Indonesian hot pepper (Capsicum annuum L.). A shed-microspore culture protocol was developed which outperformed all the previously reported methods of haploid production in pepper. The critical factors of the protocol are: selection of flower buds with more than 50% late unicellular microspores, a 1 day 4°C pretreatment of the buds, followed by culture of the anthers in double-layer medium system for 1 week at 9°C and thereafter at 28°C in continuous darkness. The medium contained Nitsch components and 2% maltose, with 1% activated charcoal in the solid under layer and 2.5 μM zeatin and 5 μM indole-3-acetic acid in the liquid upper layer. All the ten genotypes of hot pepper tested, responded to this protocol. The best genotypes produced four to seven plants per original flower bud. This protocol can be used as a potential tool for producing doubled haploid p...

Journal of Experimental Botany, 2008

The inaccessibility of the zygote and proembryos of angiosperms within the surrounding maternal a... more The inaccessibility of the zygote and proembryos of angiosperms within the surrounding maternal and filial tissues has hampered studies on early plant embryogenesis. Somatic and gametophytic embryo cultures are often used as alternative systems for molecular and biochemical studies on early embryogenesis, but are not widely used in developmental studies due to differences in the early cell division patterns with seed embryos. A new Brassica napus microspore embryo culture system, wherein embryogenesis highly mimics zygotic embryo development, is reported here. In this new system, the donor microspore first divides transversely to form a filamentous structure, from which the distal cell forms the embryo proper, while the lower part resembles the suspensor. In conventional microspore embryogenesis, the microspore divides randomly to form an embryonic mass that after a while establishes a protoderm and subsequently shows delayed histodifferentiation. In contrast, the embryo proper of filamentbearing microspore-derived embryos undergoes the same ordered pattern of cell division and early histodifferentiation as in the zygotic embryo. This observation suggests an important role for the suspensor in early zygotic embryo patterning and histodifferentiation. This is the first in vitro system wherein single differentiated cells in culture can efficiently regenerate embryos that are morphologically comparable to zygotic embryos. The system provides a powerful in vitro tool for studying the diverse developmental processes that take place during the early stages of plant embryogenesis.

Induksi Androgenesis Kedelai melalui Kultur Antera pada Media Dua-Iapis untuk Pengembangan Teknologi Haploid dalam Percepatan Proses Pemuliaan

Cara Cepat Dapat Tetua Cabai Hibrida

The Bemisia tabaci species complex: additions from different parts of the world

Bemisia tabaci is one of the most threatening pests in many crops. We sequenced part of the mitoc... more Bemisia tabaci is one of the most threatening pests in many crops. We sequenced part of the mitochondrial cytochrome oxidase I gene from fifty whitefly populations collected in Indonesia, Thailand, India and China. Nineteen unique sequences (haplotypes) of the cytochrome oxidase I were identified in these populations. They were combined with sequences available in databases, resulting in a total of 407 haplotypes and analyzed together with nine outgroup accessions. A phylogenetic tree was calculated using the maximum likelihood method. The tree showed that all groups that were found in previous studies were also present in our study. Additionally, seven new groups were identified based on the new haplotypes. Most B. tabaci haplotypes grouped based on their geographical origin. Two groups were found to have a worldwide distribution. Our results indicate that our knowledge on the species complex around B. tabaci is still far from complete.

Soybean (Glycine max L. Merr) is a very important crop in Indonesia. The creation of new elite va... more Soybean (Glycine max L. Merr) is a very important crop in Indonesia. The creation of new elite varieties is one approach to increase the national production of soybean. We have developed several potential lines of soybean to be released as a new varieties. Before releasing as new varieties, the productivity of these lines has to be evaluated in several locations. Therefore the objective of this research was to evaluate the productivity of six lines of soybean resulted from the cross between Slamet and Nokonsawon varieties, i.e. KH8, KH9, KH31, KH38, KH55, and KH71 in Majalengka, West Java, Indonesia. Four national elite varieties i.e. Anjasmoro, Slamet, Tanggamus and Wilis were used as standard. The experiment was conducted in two seasons by using randomized block design, with three blocks as replication. The result showed that based on the seed production per plant in two seasons, all six lines have higher productivity than Anjasmoro variety. The seeds of these six lines are bigger than that of standard varieties. Analysis of production stability in two seasons showed that KH71 is the most stable genotype in Majalengka. By comparing to Anjasmoro variety in two seasons, all six lines have a potential to be released as new varieties with high productivity and big seed.

Identification of silverleaf whitefly resistance in pepper

Plant Breeding, 2011

Whitefly is economically one of the most threatening pests of pepper worldwide, which is mainly c... more Whitefly is economically one of the most threatening pests of pepper worldwide, which is mainly caused by its ability to transmit many different viruses. In this research, we characterized pepper germplasm to identify whitefly-resistant accessions that will form the basis for future resistance breeding. Forty-four pepper accessions representing four species (Capsicum annuum, C. frutescens, C. chinense, C. baccatum) were screened

Planta, 2007

Gain-of-function studies have shown that ectopic expression of the BABY BOOM (BBM) AP2/ ERF domai... more Gain-of-function studies have shown that ectopic expression of the BABY BOOM (BBM) AP2/ ERF domain transcription factor is suYcient to induce spontaneous somatic embryogenesis in Arabidopsis (Arabidopsis thaliana (L.) Heynh) and Brassica napus (B. napus L.) seedlings. Here we examined the eVect of ectopic BBM expression on the development and regenerative capacity of tobacco (Nicotiana tabacum L.) through heterologous expression of Arabidopsis and B. napus BBM genes. 35S::BBM tobacco lines exhibited a number of the phenotypes previously observed in 35S::BBM Arabidopsis and B. napus transgenics, including callus formation, leaf rumpling, and sterility, but they did not undergo spontaneous somatic embryogenesis. 35S::BBM plants with severe ectopic expression phenotypes could not be assessed for enhanced regeneration at the seedling stage due to complete male and female sterility of the primary transformants, therefore fertile BBM ectopic expression lines with strong misexpression phenotypes were generated by expressing a steroid-inducible, posttranslationally controlled BBM fusion protein (BBM:GR) under the control of a 35S promoter. These lines exhibited spontaneous shoot and root formation, while somatic embryogenesis could be induced from in-vitro germinated seedling hypocotyls cultured on media supplemented with cytokinin. Together these results suggest that ectopic BBM expression in transgenic tobacco also activates cell proliferation pathways, but diVerences exist between Arabidopsis/B. napus and N. tabacum with respect to their competence to respond to the BBM signalling molecule.

Innovations in microspore embryogenesis in Indonesian hot pepper (Capsicum annuum L.) and Brassica napus L

Hot pepper ( Capsicum annuum L.) is the most important vegetable in Indonesia , but the yield is ... more Hot pepper ( Capsicum annuum L.) is the most important vegetable in Indonesia , but the yield is low, and the breeding programs are confined to the conventional methods and not efficient. To improve the efficiency of the breeding programs by speeding up the production of homozygous lines, studies were aimed at the introduction of haploid technology, which includes the regeneration and the production of doubled haploid plants from gametes. This technique is well developed in the model species Brassica napus L. via microspore culture. The results of various investigations involving both applied and fundamental aspects on microspore embryogenesis are presented in this thesis. The main results of the applied part deal with the development of an efficient shed-microspore culture protocol for the production of doubled haploid plants in Indonesian hot pepper ( C. annuum ), and its implementation under the local conditions of Indonesia. With regard to the more fundamental part, we presented...

An Efficient Anther Culture on Double-Layered Media to Produce Doubled Haploid Plants of Pepper (Capsicum annuum)

Methods in molecular biology, 2021

An efficient anther culture on double-layered media to produce doubled haploid (DH) plants in pep... more An efficient anther culture on double-layered media to produce doubled haploid (DH) plants in pepper (Capsicum annuum) was clearly shown to outperformed other techniques such as anther culture on solid medium and direct isolated microspore culture on liquid medium. It was even used for DH production in a cayenne type of hot pepper which was previously known as less responsive or even more recalcitrant to androgenesis than sweet bell pepper. Indeed, anther culture on double-layered media has been routinely used to produce DH plants on broad genotypes of C. annuum as parental candidates to develop hybrid varieties. The step-by-step protocol of pepper anther culture on double-layered media, we hereby present in detail, includes the growth of donor plants, the use of flower buds as anther source, flower bud disinfection, anther isolation, anther culture and incubation processes, embryo germination and plant acclimatization process, and transplanting of plants to the soil-compost medium ...

Plant Cell Reports, 2005

Various systems of anther and microspore cultures were studied to establish an efficient doubled ... more Various systems of anther and microspore cultures were studied to establish an efficient doubled haploid production method for Indonesian hot pepper (Capsicum annuum L.). A shed-microspore culture protocol was developed which outperformed all the previously reported methods of haploid production in pepper. The critical factors of the protocol are: selection of flower buds with more than 50% late unicellular microspores, a 1 day 4°C pretreatment of the buds, followed by culture of the anthers in double-layer medium system for 1 week at 9°C and thereafter at 28°C in continuous darkness. The medium contained Nitsch components and 2% maltose, with 1% activated charcoal in the solid under layer and 2.5 μM zeatin and 5 μM indole-3-acetic acid in the liquid upper layer. All the ten genotypes of hot pepper tested, responded to this protocol. The best genotypes produced four to seven plants per original flower bud. This protocol can be used as a potential tool for producing doubled haploid palnt sfor hot pepper breeding.

HAYATI Journal of Biosciences, 2017

Falcataria moluccana is important for reforestation and afforestation in Indonesia. However, epid... more Falcataria moluccana is important for reforestation and afforestation in Indonesia. However, epidemic of gall rust disease in F. moluccana plantations decreases its productivity. Genetic engineering is an alternative solution to against gall rust disease. Somatic embryogenesis is an efficient in vitro plant regeneration for successful plant improvement through genetic engineering. The objective of this study was to investigate the effect of thidiazuron and light treatments on the induction of somatic embryogenesis of F. moluccana. The effects of thidiazuron concentration (5, 10 or 15 mM) and light (continuous light, 7 days of dark followed by light, or continuous dark) on the induction of somatic embryogenesis in leaf explants were assessed. The highest production of somatic embryos was obtained in 5 mM thidiazuron and dark treatments for 7 days followed by light in Murashige and Skoog medium supplemented with 1.2 g/ L proline. Histological analysis in globular and cotyledon stages confirmed that cells had progressed to secondary somatic embryogenesis. This research needs more improvements to become a successful and efficient somatic embryogenesis method and as a potential method for successful plant improvement through genetic engineering in F. moluccana.

Prosedur yang efisien untuk memproduksi tanaman ha~loid ganda (HG) beberapa genotipe cabai Indone... more Prosedur yang efisien untuk memproduksi tanaman ha~loid ganda (HG) beberapa genotipe cabai Indonesia melalui k • antera dalam sistem media dua-lapis telah berhasil drlakukan d1 Belanda melalur proyek ke!Jasama lndonesra-Bela (BIORIN). lmplementasi prosedur ini pada kondisi lokal di Bogar mendapat hambatan, terutama masalah kontamrnasr pa.::. kultur dan kondisi lingkungan pertumbuhan tanaman sumber eksplan yang berbeda. Kntena kuncup bunga sumber eks pada HG Galaxy untuk fase perkembangan mikrospora lebih dari 50% pada fase akhir berinti tunggal adalah ketika pesama tinggi sampai sedikit lebih dari sepal , dan dicirikan dari munculnya warna unggu pada UJUng antera sampar seteng dari panjang antera. Penanganan masalah kontaminasi kultur in vitro berhasil dilakukan dengan menambahan kombrna antibiotik Rifampisin 10 mg/1 dan Timentin 400 gil dalam medium carr. Prosedur hasrl_ adaptasr 101 telah b~rhasrl drcoba. untuk beberapa ku ltivar cabai lokal , misalnya Tanjung. Pengecambahan dan akhmatrsasr berhasrl drlakukan d e~ tahapan mengecambahkan embrio lengkap pada media-agar Y, MS dalam botol kultur, akhmatrsasr ddakukan _ pa campuran media tanah :kasting:arang sekam (1 :1:1) dengan pengaturan kelembaban. Pro~edur yang telah dradaptasr_ pa• kondisi lokal ini akan menjadi dasar untuk memproduksi secara cepat tanaman HG cabar kultrvar lokal, untuk selanjutr dilakukan persilangan dialel sebagai upaya un tuk memperoleh beberapa kandidat varietas hibrida cabai unggul berbas: kultivar lokal.

Tinjauan ulang pengembangan teknologi haploid cabai dan prospeknya untuk percepatan penelitian genetika dan pemuliaan tanaman

Gain-of-function studies have shown that ectopic expression of the BABY BOOM (BBM) AP2/ ERF domai... more Gain-of-function studies have shown that ectopic expression of the BABY BOOM (BBM) AP2/ ERF domain transcription factor is suYcient to induce spontaneous somatic embryogenesis in Arabidopsis (Arabidopsis thaliana (L.) Heynh) and Brassica napus (B. napus L.) seedlings. Here we examined the eVect of ectopic BBM expression on the development and regenerative capacity of tobacco (Nicotiana tabacum L.) through heterologous expression of Arabidopsis and B. napus BBM genes. 35S::BBM tobacco lines exhibited a number of the phenotypes previously observed in 35S::BBM Arabidopsis and B. napus transgenics, including callus formation, leaf rumpling, and sterility, but they did not undergo spontaneous somatic embryogenesis. 35S::BBM plants with severe ectopic expression phenotypes could not be assessed for enhanced regeneration at the seedling stage due to complete male and female sterility of the primary transformants, therefore fertile BBM ectopic expression lines with strong misexpression phenotypes were generated by expressing a steroid-inducible, posttranslationally controlled BBM fusion protein (BBM:GR) under the control of a 35S promoter. These lines exhibited spontaneous shoot and root formation, while somatic embryogenesis could be induced from in-vitro germinated seedling hypocotyls cultured on media supplemented with cytokinin. Together these results suggest that ectopic BBM expression in transgenic tobacco also activates cell proliferation pathways, but diVerences exist between Arabidopsis/B. napus and N. tabacum with respect to their competence to respond to the BBM signalling molecule.

Refinement of shed-microspore culture protocol to increase normal embryos production in hot pepper (Capsicum annuum L.)

Scientia Horticulturae, 2011

Abstract A low percentage of normal-looking embryos (20%) is still a problem in an efficient shed... more Abstract A low percentage of normal-looking embryos (20%) is still a problem in an efficient shed-microspore culture of hot pepper (Capsicum annuum L.) and it is more a serious problem in other androgenesic culture systems of pepper. Therefore, several factors were investigated to refine the protocol in order to increase the percentage of normal-looking embryos. The most important factors which improved the protocol and resulted in a significantly higher percentage of normal-looking embryos produces (>50%), were delayed enrichment of the liquid upper layer medium with 2.5 μM Zeatin and 5 μM IAA, and reduced incubation temperature from 28 °C to 21 °C, both after 3 weeks of culture. Addition of 1% activated charcoal in the solid lower layer of the medium enhanced the total embryo yield only, while an application of abscisic acid and increased osmolality medium had a detrimental effect on embryo production. The use of doubled haploid lines as anther donor plants has clearly decreased the variability and improved the statistical analysis of treatment effects. A higher percentage of normal embryos are produced with this refined protocol, and is therefore more suitable for implementation in the breeding programs of hot pepper.

Successful development of a shed-microspore culture protocol for doubled haploid production in Indonesian hot pepper ( Capsicum annuum L

Plant Cell Reports, 2006

Various systems of anther and microspore cultures were studied to establish an efficient doubled ... more Various systems of anther and microspore cultures were studied to establish an efficient doubled haploid production method for Indonesian hot pepper (Capsicum annuum L.). A shed-microspore culture protocol was developed which outperformed all the previously reported methods of haploid production in pepper. The critical factors of the protocol are: selection of flower buds with more than 50% late unicellular microspores, a 1 day 4°C pretreatment of the buds, followed by culture of the anthers in double-layer medium system for 1 week at 9°C and thereafter at 28°C in continuous darkness. The medium contained Nitsch components and 2% maltose, with 1% activated charcoal in the solid under layer and 2.5 μM zeatin and 5 μM indole-3-acetic acid in the liquid upper layer. All the ten genotypes of hot pepper tested, responded to this protocol. The best genotypes produced four to seven plants per original flower bud. This protocol can be used as a potential tool for producing doubled haploid p...

Journal of Experimental Botany, 2008

The inaccessibility of the zygote and proembryos of angiosperms within the surrounding maternal a... more The inaccessibility of the zygote and proembryos of angiosperms within the surrounding maternal and filial tissues has hampered studies on early plant embryogenesis. Somatic and gametophytic embryo cultures are often used as alternative systems for molecular and biochemical studies on early embryogenesis, but are not widely used in developmental studies due to differences in the early cell division patterns with seed embryos. A new Brassica napus microspore embryo culture system, wherein embryogenesis highly mimics zygotic embryo development, is reported here. In this new system, the donor microspore first divides transversely to form a filamentous structure, from which the distal cell forms the embryo proper, while the lower part resembles the suspensor. In conventional microspore embryogenesis, the microspore divides randomly to form an embryonic mass that after a while establishes a protoderm and subsequently shows delayed histodifferentiation. In contrast, the embryo proper of filamentbearing microspore-derived embryos undergoes the same ordered pattern of cell division and early histodifferentiation as in the zygotic embryo. This observation suggests an important role for the suspensor in early zygotic embryo patterning and histodifferentiation. This is the first in vitro system wherein single differentiated cells in culture can efficiently regenerate embryos that are morphologically comparable to zygotic embryos. The system provides a powerful in vitro tool for studying the diverse developmental processes that take place during the early stages of plant embryogenesis.

Induksi Androgenesis Kedelai melalui Kultur Antera pada Media Dua-Iapis untuk Pengembangan Teknologi Haploid dalam Percepatan Proses Pemuliaan

Cara Cepat Dapat Tetua Cabai Hibrida

The Bemisia tabaci species complex: additions from different parts of the world

Bemisia tabaci is one of the most threatening pests in many crops. We sequenced part of the mitoc... more Bemisia tabaci is one of the most threatening pests in many crops. We sequenced part of the mitochondrial cytochrome oxidase I gene from fifty whitefly populations collected in Indonesia, Thailand, India and China. Nineteen unique sequences (haplotypes) of the cytochrome oxidase I were identified in these populations. They were combined with sequences available in databases, resulting in a total of 407 haplotypes and analyzed together with nine outgroup accessions. A phylogenetic tree was calculated using the maximum likelihood method. The tree showed that all groups that were found in previous studies were also present in our study. Additionally, seven new groups were identified based on the new haplotypes. Most B. tabaci haplotypes grouped based on their geographical origin. Two groups were found to have a worldwide distribution. Our results indicate that our knowledge on the species complex around B. tabaci is still far from complete.

Soybean (Glycine max L. Merr) is a very important crop in Indonesia. The creation of new elite va... more Soybean (Glycine max L. Merr) is a very important crop in Indonesia. The creation of new elite varieties is one approach to increase the national production of soybean. We have developed several potential lines of soybean to be released as a new varieties. Before releasing as new varieties, the productivity of these lines has to be evaluated in several locations. Therefore the objective of this research was to evaluate the productivity of six lines of soybean resulted from the cross between Slamet and Nokonsawon varieties, i.e. KH8, KH9, KH31, KH38, KH55, and KH71 in Majalengka, West Java, Indonesia. Four national elite varieties i.e. Anjasmoro, Slamet, Tanggamus and Wilis were used as standard. The experiment was conducted in two seasons by using randomized block design, with three blocks as replication. The result showed that based on the seed production per plant in two seasons, all six lines have higher productivity than Anjasmoro variety. The seeds of these six lines are bigger than that of standard varieties. Analysis of production stability in two seasons showed that KH71 is the most stable genotype in Majalengka. By comparing to Anjasmoro variety in two seasons, all six lines have a potential to be released as new varieties with high productivity and big seed.

Identification of silverleaf whitefly resistance in pepper

Plant Breeding, 2011

Whitefly is economically one of the most threatening pests of pepper worldwide, which is mainly c... more Whitefly is economically one of the most threatening pests of pepper worldwide, which is mainly caused by its ability to transmit many different viruses. In this research, we characterized pepper germplasm to identify whitefly-resistant accessions that will form the basis for future resistance breeding. Forty-four pepper accessions representing four species (Capsicum annuum, C. frutescens, C. chinense, C. baccatum) were screened

Planta, 2007

Gain-of-function studies have shown that ectopic expression of the BABY BOOM (BBM) AP2/ ERF domai... more Gain-of-function studies have shown that ectopic expression of the BABY BOOM (BBM) AP2/ ERF domain transcription factor is suYcient to induce spontaneous somatic embryogenesis in Arabidopsis (Arabidopsis thaliana (L.) Heynh) and Brassica napus (B. napus L.) seedlings. Here we examined the eVect of ectopic BBM expression on the development and regenerative capacity of tobacco (Nicotiana tabacum L.) through heterologous expression of Arabidopsis and B. napus BBM genes. 35S::BBM tobacco lines exhibited a number of the phenotypes previously observed in 35S::BBM Arabidopsis and B. napus transgenics, including callus formation, leaf rumpling, and sterility, but they did not undergo spontaneous somatic embryogenesis. 35S::BBM plants with severe ectopic expression phenotypes could not be assessed for enhanced regeneration at the seedling stage due to complete male and female sterility of the primary transformants, therefore fertile BBM ectopic expression lines with strong misexpression phenotypes were generated by expressing a steroid-inducible, posttranslationally controlled BBM fusion protein (BBM:GR) under the control of a 35S promoter. These lines exhibited spontaneous shoot and root formation, while somatic embryogenesis could be induced from in-vitro germinated seedling hypocotyls cultured on media supplemented with cytokinin. Together these results suggest that ectopic BBM expression in transgenic tobacco also activates cell proliferation pathways, but diVerences exist between Arabidopsis/B. napus and N. tabacum with respect to their competence to respond to the BBM signalling molecule.

Innovations in microspore embryogenesis in Indonesian hot pepper (Capsicum annuum L.) and Brassica napus L

Hot pepper ( Capsicum annuum L.) is the most important vegetable in Indonesia , but the yield is ... more Hot pepper ( Capsicum annuum L.) is the most important vegetable in Indonesia , but the yield is low, and the breeding programs are confined to the conventional methods and not efficient. To improve the efficiency of the breeding programs by speeding up the production of homozygous lines, studies were aimed at the introduction of haploid technology, which includes the regeneration and the production of doubled haploid plants from gametes. This technique is well developed in the model species Brassica napus L. via microspore culture. The results of various investigations involving both applied and fundamental aspects on microspore embryogenesis are presented in this thesis. The main results of the applied part deal with the development of an efficient shed-microspore culture protocol for the production of doubled haploid plants in Indonesian hot pepper ( C. annuum ), and its implementation under the local conditions of Indonesia. With regard to the more fundamental part, we presented...