Combinations Of Growth Regulators Research Articles

Androgenesis in tomato (Solanum lycopersicum L.)-Effect of genotypes, microspore development stage, pre-treatments and media composition on induction of haploids

Doubled haploid (DH) technology remarkably accelerates the crop breeding by obtaining homozygous lines in a single generation. The present study was targeted in generating haploid plants through androgenesis. Anthers from immature flower buds of six tomato genotypes viz., LE-1230, LE-1236, LE-1256 TLCV 2, PKM 1 and TNAU tomato hybrid CO 3 were used for induction of haploids. A preliminary study based on callus induction frequency (CIF), more than 5% was helpful in short listing flower bud size, pre-treatments and growth regulator combinations. Subsequently, anthers from two different sized flower buds (4 and 6 mm length), dissected either from fresh or pre-treated flower buds (2 and 5 days in dark at 4 °C or gamma irradiated) were inoculated in MS medium fortified with different growth regulators for callus induction. Among the genotypes, TLCV 2 had recorded the maximum CIF (38.80%) from anthers of 4 mm long flower buds followed by TNAU tomato hybrid CO 3 (34.70%). Throughout the study, anthers from 4 mm long flower buds responded the best for callus induction. Among the pre-treatments, anthers from gamma irradiated flower buds recorded the highest CIF (31.90%) when compared to others. Cold shock (4 °C) in dark to flower buds for 2 days had improved the CIF of anthers when compared to fresh in LE 1230, LE 1238, TLCV2 and TNAU tomato hybrid CO 3, but when the cold shock was increased to 5 days, invariably there was a reduction in CIF in all the six genotypes. TA 8 (MS + 2iP (0.5 mg L-1) + NAA (0.5 mg L-1)) medium was found to be the best for maximum CIF in LE 1230 and PKM1, TA1 (MS + 2iP (1.0 mg L-1) + IAA (2.0 mg L-1)) in LE 1238, LE 1256 and TNAU tomato hybrid CO 3 and TA7 (MS + 2iP (0.5 mg L-1) + Kinetin (1.5 mg L-1) + NAA (1.0 mg L-1)) for TLCV 2 genotypes. The callus induced was sub cultured at monthly intervals in the same medium for proliferation and later transferred to regeneration medium. A good number of shoots got regenerated only from anther calli of TNAU hybrid CO 3 that was sub cultured in MS medium fortified with Zeatin (0.5 mg L-1). The clumps of shoots induced were separated and inoculated in MS medium supplemented with GA3 (0.5 mg L-1) for shoot elongation. After 4-6 weeks, the elongated shoots were transferred to half strength MS medium enhanced with IBA (1 mg L-1). Profuse rooting from the base of the shoot was noticed in 4-5 weeks. The stomatal count with leaves from the diploid plants and in vitro plants observed were 3-4 and 1 respectively indicating the haploidy nature of in vitro plants.

Study of Five Clones with Combinations of Growth Regulators Based on Growth and Anatomical Characteristics of Rubber Plant (Hevea brasiliensis L.)

As an export commodity, rubber is a major contributor to Indonesia's foreign exchange. Regarding the increase in rubber production, a study on combinations of growth regulators and rubber clones has been carried out based on plant growth and anatomical characteristics during the immature plant period. This research is conducted for eighteen months at the KSO Karang Inong plantations, PTPN-I, and PTPN-III, East Aceh District, using five clones. This study adopts a nested design with three factors: clones, Growth Regulators (GRs), and paclobutrazol. The clones used are PB 260, IRR 104, IRR 112, IRR 39, and 105. The GRs combination factor between IAA and Kinetin consists of seven levels and three levels of paclobutrazol. The results show that the rubber clones PB260 and IRR105 give higher stem girth and plant height than the other clones when applied with GRs at six different levels. The most expansive leaf area is found in clone IRR 104 compared to other clones. In addition, paclobutrazol affects plant height. Applying paclobutrazol can reduce plant height for all clones but increases stem girth, skin thickness, number and diameter of latex vessels, and total chlorophyll at 46 months after treatment.

Micropropagation of strawberry (Fragaria ananassa “pajaro”)by meristem culture method

Experiments were carried out to examine the effects of different combinations of plant growth regulators in vitro micropropagation of strawberry plants. Specimens were sterilised by a different concentration of sodium hypochlorite - NaOCl (1, 2, and 3%) for 20 mins. A meristem was separated and cultured on Murashige and Skoog (MS) containing 0.3 mg/l BAP for 8 weeks. Initial shoots were transferred to MS with various concentrations of BAP (0, 0.1, 0.3, and 0.5 mg/l) and kinetin (0, 0.1, 0.2, and 0.3 mg/l) in either single or combination. After 6 weeks of culture, the regenerated shoots were transferred on 1/2 MS with different concentrations of NAA (0, 0.1, 0.3, 0.5, 0.7, and 1.0 mg/l) and BAP (0, 0.1, 0.3, and 0.5 mg/l) in either single or combination. The results showed that the lowest percentage of contamination (10%) and the highest percentage of regeneration (80%) response were achieved on MS media by sterilisation with 3% NaOCl for 20 mins. The highest shoot proliferation per explant (16.2 shoots/explant) was reached on MS with 0.3 mg/l BAP plus 0.1 mg/l kinetin. 1/2 MS media with 0.1 mg/l NAA plus 0.1 mg/l BAP induced 14.4 roots per shoot and produced the longest roots (9.1 cm). However, the higher concentration of NAA (0.3-1.0 mg/l) or in combination with BAP resulted in callus formation. The plantlets, thus developed, were hardened and successfully established in soil containing organic fertiliser: Trichoderma: coconut peat (1:1:1 v/v/v).

Flower-inducing technology facilitates speed breeding in cassava.

Cassava is a tropical crop that provides daily carbohydrates to more than 800 million people. New cassava cultivars with improved yield, disease resistance, and food quality are critical to end hunger and reduce poverty in the tropics. However, the progress of new cultivar development has been dragged down by difficulties obtaining flowers from desired parental plants to enable designed crosses. Inducing early flowering and increasing seed production are crucial to improving the efficiency of developing farmer-preferred cultivars. In the present study, we used breeding progenitors to evaluate the effectiveness of flower-inducing technology, including photoperiod extension, pruning, and plant growth regulators. Photoperiod extension significantly reduced the time to flowering in all 150 breeding progenitors, especially late-flowering progenitors which were reduced from 6-7 months to 3-4 months. Seed production was increased by using the combination of pruning and plant growth regulators. Combining photoperiod extension with pruning and the PGR 6-benzyladenine (synthetic cytokinin) produced significantly more fruits and seeds than only photoperiod extension and pruning. Another growth regulator, silver thiosulfate, commonly used to block the action of ethylene, did not show a significant effect on fruit or seed production when combined with pruning. The present study validated a protocol for flower induction in cassava breeding programs and discussed factors to consider in implementing the technology. By inducing early flowering and increasing seed production, the protocol helped move one step further for speed breeding in cassava.

Callus induction of Calotropis gigantea using BAP and 2,4-D in vitro

Calotropis gigantea is a plant not widely used but has potential as a medicinal plant. The phytochemical compound can be produced faster using a tissue culture and a combination of growth regulators. The research objectives were to study the effect and determine the best concentration of BAP and 2,4-D in callus induction of Calotropis gigantea. This research was carried out in the Plant Physiology and Biotechnology Laboratory, Faculty of Agriculture, Sebelas Maret University, from September to November 2021. A month-old Calotropis gigantea stem was used as an explant. The research used three replicates of a completely randomized design with 25 combination treatments. The culture medium was MS with BAP (0; 0.5; 1; 1.5; 2 ppm) and 2,4-D (0; 0.5; 1; 1.5; 2 ppm) supplements. Parameters observed in this research were callus formation time, callus colour, and callus texture. The results showed that a combination of BAP 0.5 ppm + 2,4-D 1.5 ppm could induce callus faster than other treatments, 6 days. Callus morphology with green color and compact texture resulted from a combination of BAP 1.5 ppm + 2,4-D 1.5 ppm treatment.

Plant Regeneration in Amorphophallus muelleri Blume. through Organogenic

Porang (Amorphophallus muelleri Blume.) usually used to functional food raw materials, caused its high glucomant content. Limitation of conventional propagation both vegetative and generative affected to decreasing of porang production to fulfil market demand. To solve the problem, plant tissue culture technique was chosen to rapid propagate bulbils of porang. So, the aim of this research to determine the combination and concentration of Plant growth Regulators (PGRs), such as 6-Benzylaminopurine (BAP), Naphthaleneacetic Acid (NAA), and Thidiazuron (TDZ) for quality of callus, also growth of callus and shoots for rapid propagation of porang, cause PGRs are one of factors that affect the success of in vitro propagation. Experimental design of this research was completely randomized designed with statistical analysis using analysis of variance (Anova) one way. Difference combination and concentration of cytokinin and auxin as manipulation variables, which several parameters growth of callus, shoots, and roots was observed to indicate the rapid organogenic of porang. The optimal shoot induction medium was Murashige and Skoog (MS) media with 5.0 mg.L-1 BAP and 0.2 mg.L-1 NAA on which number of shoots and shoot height reached 15±1.8 and (7.2±1.86) cm. After shoot formation stage, the proper media for rooting stage was determined, which was Murashige and Skoog (MS) media with 1.0 mg.L-1 NAA resulted the rooting rate reached 100% and roots appear earlier. Optimal combination and concentration of PGRs on micropropagation of Amorphophallus muelleri Blume. from bulbils explant should be known to increase the production of porang, which can fulfil the market demand.

Establishment of a suitable regeneration protocol for rapid propagation of Piper nigrum L. through in vitro culture

An experiment was performed to establish a suitable regeneration protocol for the rapid propagation of Piper nigrum L. using nodal segments and leaf tissues as explants through direct and indirect organogenesis. After surface sterilization, several types of explant were inoculated onto gelled MS medium containing various concentrations and combinations of growth regulators for callus and direct shoot induction. The highest callus induction frequency was 92% and 84% in the case of leaf tissues and nodal segments, respectively, in gelled MS medium containing 2.0 mg/l 2,4-D. Multiple shoots (6.43±0.35 shoots per unit callus) were obtained when the calli from both explant types were cultured on MS medium containing 1.0 mg/l BAP. Nodal segments showed the best result (85%) in terms of direct shoot induction in MS medium supplemented with 1.5 mg/l BAP, where the highest number of shoots per explant was 5.03±0.69. The directly induced shoots were multiplied and elongated on MS medium containing 1.0 mg/l BAP and 0.5 mg/l IBA, the number and length of regenerated shoots per culture being 6.07±0.39 and 5.84±0.65 cm, respectively. The best response to root induction (86.67%) was observed when shoots were transferred to ½ strength of gelled MS medium supplemented with 1.5 mg/l IBA within 16-24 days, with 13.60±1.76 roots per shoot unit. The well-rooted shoots were successfully acclimated in a mixture of soil, sand, and compost (1:1:1) with a survival rate of 88%.
 Jahangirnagar University J. Biol. Sci. 11(1 & 2): 31-40, 2022 (June & December)

In vitro micropropagation of Bromelia balansae Mez.: effects of light intensity and growth regulators on plant development

We detail herein the in vitro micropropagation of Bromelia balansae Mez. In this regard, we investigated the germination and the action of growth regulators in inducing callogenesis. Furthermore, we thoroughly investigated the influence of light intensity on plant growth as well as the production of secondary metabolites. The germination rate of B. balansae seeds was 94.95% and the developed seedlings were uniform. It was possible to observe that the amount of callus formed per explant was influenced by the concentrations and combinations of distinct growth regulators. Furthermore, it was possible to observe variations in the concentration of total phenolic compounds and flavonoids in the extracts of the plants cultivated under different light intensities. Therefore, this study showcases the effect of growth conditions in the morphology and chemical constitution of in vitro grown B. balansae.

Somatic Embryogenesis and Flow Cytometric Assessment of Nuclear Genetic Stability for Sansevieria spp.: An Approach for In Vitro Regeneration of Ornamental Plants

Sansevieria Thunb. species are traditionally known as succulent ornamental plants worldwide. They are also cultivated for medicinal, fodder, soil conservation and fiber uses, and for their capacity to reduce environmental pollution. Sansevieria sexual propagation is limited by the lack of viable seeds, and reproduction is largely made via vegetative propagation by suckers or cuttings. For these reasons, genetic improvement by conventional breeding is limited. To overcome this problem and to address the increasing demand from customers for novel Sansevieria varieties, many commercial companies regularly use in vitro propagation, as is the case in the breeding process of several ornamental plants. In this paper, for the first time, we report a procedure for in vitro somatic embryogenesis and plant regeneration starting from three flower explants for seven different Sansevieria genotypes. Regeneration was attempted using stigmas/styles, anther/filament, and ovary which were cultured on a Murashige and Skoog solidified medium under three different plant growth regulator combinations. A good regeneration rate was obtained with all genotypes used under all culture conditions tested from every explant type, with percentages ranging from 0 to 73.3%. “Genetic stability” assessment of regenerated plants in respect to their mother plants was verified through flow cytometry analysis showing a high degree of uniformity, with only S. parva exhibiting a different level of DNA fluorescence among in vitro regenerated plants. This is an interesting achievement in the aim to produce true-to-type plants and new variants with desirable characteristics, both of which are desired features in ornamentals improvement.

MULTIPLICACIÓN in vitro DE Phalaenopsis sp. USANDO REGULADORES DE CRECIMIENTO VEGETAL, AGUAMIEL Y PULQUE (COMPLEJOS ORGÁNICOS)

<p><strong>Background:</strong> <em>Phalaenopsis</em> is an orchid of economic importance worldwide. Its natural reproduction is slow due to its monopodial growth (a single apical meristem). Therefore, it is necessary to make <em>in vitro</em> propagation protocols more efficient. <strong>Objectives:</strong> 1. To evaluate three concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) in combination with three of 6-Benzyl Adenine (BA) in the <em>in vitro</em> induction of protocormic like bodies (PLBs) at from leaf explants of <em>Phalaenopsis</em> sp. var. Dudu, under three periods of darkness, 2. To test the effect of four concentrations of honey water and fermented sap, as organic complexes (CO), on the <em>in vitro</em> multiplication rate of PLBs. <strong>Methodology:</strong> Two tests were carried out: Test 1. Three concentrations of 2,4-D (3, 4, 5 mgL<sup>-1</sup>) and three of BA (1, 2, 3 mgL<sup>-1</sup>) were evaluated in leaf explants of <em>Phalaenopsis</em> sp., combined with three periods of darkness 14, 21, 28 days in a completely randomized design with a trifactorial arrangement (27x10). Test 2. Four concentrations of honey water and fermented sap (0, 10, 50, 100 mlL<sup>-1</sup>) were evaluated, arranged in a completely random design (8x10). <strong>Results:</strong> The best combination of plant growth regulators (PGR) for the formation of PLBs (14 PLBs/explant) was with 5 mgL<sup>-1</sup> of 2,4-D and 2 mgL<sup>-1</sup> of BA, during 21 days of darkness. Regarding the use of CO, the addition of 10 mlL<sup>-1</sup> of fermented sap and 50 mlL<sup>-1</sup> of honey water induced the highest rates of multiplication of PLBs/explant (41.4 and 39.6 PLBs). The regeneration of <em>Phalaenopsis</em> sp. from PLBs occurred in 225 days. <strong>Implications:</strong> The results obtained in the two trials are the basis for establishing a protocol for the multiplication of <em>Phalaenopsis</em> sp. <strong>Conclusions:</strong> The combination of 5 mgL<sup>-1</sup> of 2,4-D and 2 mgL<sup>-1</sup> of BA produced the highest number of PLBs/explant (14) at 21 days of darkness and subsequent light exposure for six weeks. On the other hand, the addition of 10 mlL<sup>-1</sup> of fermented sap and 50 mlL<sup>-1</sup> of honey water as CO induced the highest rates of PLBs multiplication (41.4 and 39.6 PLBs, respectively). 100% survival of seedlings was observed after 21 days of acclimatization, under greenhouse conditions.</p>

Potential and Constraints on In Vitro Micropropagation of Juniperus drupacea Labill.

Juniperus drupacea Labill. (Cupressaceae) is a species with ecological and medicinal value. In Europe, it is native only in southern Greece, and is listed as endangered. Due to its uniqueness, this study attempted, for the first time, an in vitro propagation effort of Syrian juniper. Explants of the lateral shoot tips were surface-sterilized and cultured on Murashige and Skoog (MS) medium. The cultures were subcultured on MS, woody plant medium (WPM), and Driver and Kuniyaki Walnut (DKW) supplemented with different concentrations of 6-benzylaminopurine (BA), thidiazuron (TDZ), or meta-topolin [6-(3-hy-droxybenzylamino)purine] for shoot induction. Explants derived from female trees exhibited 54.17% bud proliferation on DKW medium with 4 μM meta-topolin or 4 μM TDZ and on WPM with 4 μM meta-topolin or 4 μM BA. A total of 62.50% of the male tree derived explants produced multiple shoots on DKW with 4 μM BA. The maximum average number of shoots per explant were 1.17 per explant in both cases. The length of the shoot derived from explants of female origin was 2.94 mm compared to 2.69 mm of the in vitro shoots from the explants of male trees. Overall, the best medium and plant growth regulator combination for the explants derived from both female and male trees, for the traits under study, was proven to be DKW + 4 µM TDZ. Our experiments show that Juniperus drupacea, under in vitro conditions, shows recalcitrance in rooting, as the applications of IBA, NAA, and IAA concentrations were proven to be ineffective treatments. Although the results show low values, this avant-garde study provides a foundation for further research on the in vitro regeneration of Juniperus drupacea.

Effect of different concentrations and combinations of some plant growth regulators on Punica granatum anther culture

Plant growth regulators (PGR), also known as plant hormones, are a variety of chemical compounds that have a significant impact on the development and differentiation of plant cells. This work aimed to study the effect of various combinations of Plant Growth Regulators (PGRs) for example [6-Benzyladenine (BA), 2,4-dichlorophenoxyaceticg acid (2,4-D), Naphthalene acetic acid (NAA) and indol-3-ylbutyric acid (IBA)] on callus induction and shoot regeneration from anther culture of S1 progenies resulted from Manfalouty cultivar open pollinated. The results showed that highest value of percentage of callus induction was 10.6% on MS medium supplemented with 1 mg / l of NAA and 2 mg / l of BA also highest value of percentage of shoot formation 60 % on MS medium supplemented with 3 mg/ l of NAA and 2 mg /l of BA.

Каллусные культуры Spergularia marina (L.) Griseb.: получение и фитохимический анализ

In recent decades, interest in halophyte plants has increased due to their high content of biologically active substances with powerful antioxidant, antimicrobial, anti-inflammatory and antitumor properties and promising for the prevention of various diseases. Several species of halophytes grow on the territory of the Kaliningrad region, among which the rare species Spergularia marina (L.) Griseb. is of particular interest, the biological activity and content of secondary metabolites of which have not been studied sufficiently. The purpose of this study was to obtain callus cultures, to study the content of some groups of phenolic compounds and the antioxidant activity of extracts. The study carried out the selection of growth regulators and concentrations that induce callus formation. 19 nutrient media were selected for the induction of S. marina callus cultures. The conducted phytochemical analysis showed a significant content of phenolic compounds and hydroxycinnamic acids, as well as a high level of antioxidant activity of extracts of callus cultures. Out of 19 callus cultures, cultures obtained on Murashige and Skoog nutrient media containing the following combinations of growth regulators are promising for obtaining target secondary metabolites: 0.25 mg/l TDZ and 1 mg/l 2,4-D; 0.1 mg/l TDZ and 1.5 mg/l 2,4-D; 0.25 mg/l TDZ and 0.25 mg/l IBA; 0.5 mg/l TDZ and 0.25 mg/l IBA; 0.25 mg/l KinN and 0.5 mg/l 2,4-D.

Regeneration and development of Coffea arabica L. plants through indirect somatic embryogenesis

Micropropagation of AS2K clones Arabica coffee (Coffea arabica L.) was attempted through indirect somatic embryogenesis by using ten different parts of the leaf such as shoot, first leaf base, second leaf base, third leaf base, first leaf middle, second leaf middle, third leaf middle, first leaf tip, second leaf tip, and third leaf tip. The influence of the part of leaf explants, combination of plant growth regulator (PGRs) in the induction of embryogenic callus and regeneration of embryo somatic were studied. Furthermore, the various protocols to induce regeneration of somatic embryo into plantlet through different step of subculture and the use of various germination medium were demonstrated. The morphological characteristics and histological analysis of embryogenic callus and embryo development were observed. In this experiment, it was observed that the M5 medium supplemented with 1 mg/L 2,4-D, 1 mg/L BAP and 4 mg/L 2-ip was closely associated with third leaf tip explants for induction of embryogenic callus. The maximum number of globular, heart-shape, torpedo and cotyledones (18, 4, 12, 4, respectively) were achieved on ERM6 medium containing 2 mg/L BAP without activated charcoal on 90th day for regeneration of embryo somatic. The length of roots is the most influence paramater on plantlet regeneration, and the 17th protocol which used B medium, large embryos and twice phase of subculture from liquid medium to solid medium is the best protocol for plantlet regeneration. The protocol developed could be useful highly for large-scale micropropagation in these commercially important Arabica coffee clones. Key words: Indirect somatic embryogenesis; 24-D; BAP; histology; anatomy.

Ex-Situ Conservation of An Endangered Medicinal Plant Andrographis Paniculata By Plant Tissue Culture

An effective and rapid in vitro regeneration protocol of Kalmegh (Andrographis paniculata) was established by investigating the factors like combinations of plant growth regulators and explant types (stem, leaf and midrib). To find out the effective medium for callus induction and shoot regeneration, different explants of A. paniculata were cultured on MS media enriched with several concentrations of 6-benzylaminopurine (BA), α-naphthalene acetic acid (NAA) and 2, 4-dichlorophenoxy acetic acid (2,4-D). Stem explant was noticed more responsive than leaf and midrib explant both in callus initiation and shoot regeneration. The ranges of callus initiation from stem, leaf and midrib explants were 26.67 - 100%, 20 - 93.33% and 13.33 - 73.33%, respectively. The calli obtained from midrib explants were not used in shoot initiation because of its poor size. The stem explant exhibited the maximum 73.33% shoot regeneration frequency in a comparison with leaf explants (60%). The maximum callus induction (100%) and shoot regeneration (73.33%) from stem explants were noticed in MS medium strengthened with 0.5 mg/L NAA and 2.0 mg/L BA and half strength MS media complemented with 0.1 mg/L NAA and 3.0 mg/L BA respectively. The highest shoot regeneration from the stem explant may be due to presence of more active parenchymatous cells than that of leaf explant. Half MS medium fortified with 2.0 mg/L IBA considered as best root initiation medium as it resulted in maximum rooting (93.33%). After acclimatization, the plants were transferred to field and found identical to the mother plant.

In-vitro Propagation of Dendrobium chryseum Rolfe

Dendrobium chryseum is an endangered epiphytic and lithophytic orchid species having medicinal and ornamental value. The objective of the present study is to develop micropropagation protocol for D. chryseum. The immature seeds of D. chryseum were used as an explant for the micropropagation. Protocorms were developed within 90 days in Murashige and Skoog (MS) medium without plant growth regulators. Protocorms were differentiated into micro shoots after 30 days of transfer to MS medium supplemented with 2 mg/L Benzyl amino purine (BAP), 1 mg/L kinetin and 10% coconut water. Among eleven different combinations of plant growth regulators (BAP, á-Naphthalene acetic acid (NAA), Adenine sulphate, Kinetin and coconut water) treated for shoot multiplication, maximum number of shoots were obtained in 0.5 mg/L BAP + 0.5 mg/L NAA (5.8 ± 0.53 SE shoots per explant). Longest shoot length was recorded in MS medium with Adenine sulphate (1 mg/L) (2.54 ± 0.03 cm SE). Root induction was carried out by using MS medium with different concentrations (0.5, 1, 1.5, 2.0 mg/L) of Indole butyric acid (IBA) and NAA. The highest numbers of roots and longest root length, both were observed at 2 mg/L IBA (4.63 ± 0.56 SE and 2.09 ± 0.25 cm SE respectively). 2 mg/L NAA showed poor response for root number (0.94 ± 0.21 SE) and root length (0.43 ± 0.07 cm SE). Successful acclimatization of in-vitro grown plantlets was done by wrapping the plantlet with moss kept on fine pine bark and the survival rate of plantlet was about 80% after 30 days. This protocol could be helpful for the effective mass propagation and ex situ conservation of D. chryseum.

Phenotypic variation and epigenetic insight into tissue culture berry crops.

Berry crops, a nutrient powerhouse for antioxidant properties, have long been enjoyed as a health-promoting delicious food. Significant progress has been achieved for the propagation of berry crops using tissue culture techniques. Although bioreactor micropropagation has been developed as a cost-effective propagation technology for berry crops, genetic stability can be a problem for commercial micropropagation that can be monitored at morphological, biochemical, and molecular levels. Somaclonal variations, both genetic and epigenetic, in tissue culture regenerants are influenced by different factors, such as donor genotype, explant type and origin, chimeral tissues, culture media type, concentration and combination of plant growth regulators, and culture conditions and period. Tissue culture regenerants in berry crops show increased vegetative growth, rhizome production, and berry yield, containing higher antioxidant activity in fruits and leaves that might be due to epigenetic variation. The present review provides an in-depth study on various aspects of phenotypic variation in micropropagated berry plants and the epigenetic effects on these variations along with the role of DNA methylation, to fill the existing gap in literature.

The growth performance of Rhizophora apiculata using the cut-propagule method for mangrove rehabilitation in Indonesia

Abstract. Usman AHA, Hartoyo APP, Kusmana C. 2022. The growth performance of Rhizophora apiculata using the cut-propagule method for mangrove rehabilitation in Indonesia. Biodiversitas 23: 6366-6378. A high decrease in the size of Indonesia's mangrove forests requires effective and efficient rehabilitation efforts. One of the efforts is using Rhizophora apiculata as the adaptive and fast-growing mangrove species and its cut-propagule seedling method for accelerating plant propagation. The objectives of this study were to analyze the growth performance of R. apiculata propagules with various treatments of propagule cutting, seedling media, and giving growth regulators (PGR), as well as to determine the best combination of treatment for the growth of R. apiculata. An experimental study was conducted in a greenhouse using a randomized design with 3 factors (propagule cutting, seedling media, and giving PGR) and 3 replications. The interaction of the combination of cut-propagule treatment, planting media, and growth regulator (AxBxC) only had a significant effect on the increase in the number of leaves of R. apiculata. Complete propagules and the lower part of cutting propagules with a combination of mud+sand seedling media and 10,000 ppm PGR (a0b1c1 and a2b1c1) resulted in the best value on the growth of R. apiculata. The cut-propagule seedling method of R. apiculata still showed good growth so it can be used as an alternative to mass vegetative reproduction in mangrove rehabilitation activity.

Investigation of In vitro Propagation Possibilities of Endemic Campanula phitosiana Yıldırım & Şentürk

Campanula phitosiana Yıldırım & Şentürk, is a local endemic to the Aydın Mountain range, which distribute across in Western Anatolia (both İzmir and Aydın). This species belongs to the Mediterranean basin floristic region. According to the International Union for Conservation of Nature’s criteria, C. phitosiana is classified as “Critically Endangered” (CR). The aim of the study is to develop in vitro regeneration protocol for critically endangered endemic Campanula phitosiana. To investigate the efficient medium and plant growth regulator combinations for callus initiation and shoot proliferation, petiole and leaves were used as explant and explants cultivated on MS medium including NAA (1-Naphthylacetic acid) (0.3 mg L-1), TDZ (Thidiazuron) (0.5, 1.0, 2.0, and 3.0 mg L-1), BA (6-Benzylaminopurine) (0.5, 1.0, 2.0, and 3.0 mg L-1) and Gibberellic Acid (GA3) (0.5, 1.0, 2.0, and 3.0 mg L-1). Explants subcultured 3 times. Experiments were conducted according to completely randomized design repeated with 5 replicates and each replicates including 5 explants. As a result of the experiment, callus initiation and shoot proliferation were investigated. Efficient callus initiation was observed petiole explants as 100% rate. Shoot proliferation was observed on MS medium including 0.3 mg L-1 NAA + 2.0 mg L-1 GA3.

Improvement of Anther Culture to integrate Doubled Haploid Technology in Temperate Rice (Oryza sativa L.) Breeding.

Doubled haploid (DH) plant production, such as anther culture (AC), is an effective tool used in modern rice breeding programs. The improved efficient protocols applied can shorten the process of breeding. The effect of combinations of plant growth regulators (2.5 mg/L NAA, 1 mg/L 2,4-D and 0.5 mg/L kinetin; 2 mg/L 2,4-D and 0.5 mg/L BAP) in the induction medium were compared in AC for five rice breeding materials and combinations. Induction of calli ranged from 264.6 ± 67.07 to 468.8 ± 123.2 calli/100 anthers in AC of rice genotypes. Two basal media (MS and N6) and two combinations of growth regulators (1 mg/L NAA, 1 mg/L BAP and 1 mg/L kinetin; 1.5 mg/L BAP, 0.5 mg/L NAA and 0.5 mg/L kinetin) were used as regeneration media. The in vitro green plant production was the highest with the application of the N6NDK induction medium (NAA, 2,4-D and kinetin) and the MS-based regeneration medium (1 mg/L NAA, 1 mg/BAP and 1 mg/L kinetin) in anther culture of the '1009' genotype (95.2 green plantlets/100 anthers). The mean of five genotypes was 24.48 green plantlets/100 anthers for the best treatment. Flow cytometric analyses conducted identified the microspore origin of the haploid calli produced in AC, while the uniformity of spontaneous DH plants was checked in the DH1 and DH2 generations. Spontaneous chromosome doubling ranged from 38.1% to 57.9% (mean 42.1%), depending on the breeding source. The generated and selected DH lines were tested in micro- and small-plot field experiments to identify promising lines for a pedigree breeding program. The improved AC method was integrated in a Hungarian temperate rice pedigree breeding program.