Combination Of BAP Research Articles

Propagation of Clematis ‘Warszawska Nike’ in In Vitro Cultures

A micropropagation protocol for growing Clematis ‘Warszawska Nike’ was developed. The MS medium supplemented with 1 mg∙dm−3 BAP showed good results in the case of microshoot initiation (80%). The addition of BAP to the medium at higher concentrations resulted in the formation of a large amount of callus tissue at the base of the explant. Of the explants growing on the medium with the lowest cytokinin concentration, 8% flowered. Very quickly, after just 14 days, the explants began to die: some of the leaves that developed in in vitro cultures began to turn yellow and wither. The propagation of shoots was performed in two steps. In the first step, cytokinin BAP and Kin in various concentrations (0.5–2 mg∙dm−3) were added to the MS medium. In the second step, MS medium with the combinations of BAP (0.5 and 1 mg∙dm−3) with IAA or GA3 (1 and 2 mg∙dm−3) was used. The MS medium with 0.5 mg∙dm−3 BAP and 2 mg∙dm−3 GA3 was the best medium for the multiplication stage of clematis. Plants growing on this medium had the largest number of leaves, shoots, and internodes, and were also heavier compared to plants propagated on other media. The proliferated clematis explants were rooted on MS medium with the addition of IAA or IBA in different concentrations (0.5 to 4 mg∙dm−3). Of the concentrations tested, 0.5 mg∙dm−3 IAA was the most effective one for in vitro root induction. The highest percentage of acclimatized plants (75%) was observed when the shoots were rooted on MS medium with 0.5 mg∙dm−3 IAA.

Induction of micro-rhizomes for in vitro ginger (Zingiber officinale Rosco) disease-free planting materials regeneration

Ginger has been a leading spice crop in Ethiopia until ginger bacterial wilt disease interrupted its production. The disease transmission is mainly through infected planting materials and products. Regeneration of healthy planting materials is among the best option to minimize the disease impact. This research aimed to induce and produce disease-free in vitro micro-rhizome in a combination of sucrose, BAP, ammonium nitrate, and silver nitrate. The results from observations indicated that sucrose and BAP were best combinations for induction of disease free micro-rhizomes. Ammonium nitrate and silver nitrate showed lower induction than sucrose and BAP combinations alone. The maximum viable number of micro-rhizome (5.67) and shoot number (10.33) were from 80.0 g/l sucrose and 6.0 mg/l BAP contained medium. Viability test indicated 80 % of the micro-rhizomes were sprouted after one month in soil. The micro-rhizome production potential observed in this experiment can enhance disease-free ginger production.

Callus cell and explants regeneration, glucose, mineral, antioxidant and flavonoid content development using broccoli root tip and leaf cutting in vitro.

The study was conducted to evaluate the root, shoot and leaf callus cell regeneration and its biochemical properties like antioxidant, carbohydrate, pigment and mineral content from broccoli root, shoot and leaf cutting in vitro. An in vitro factorial experiment was carried out based on a Completely Randomized Design (CRD) with 5 replicates in tissue culture applying different IBA (0.25, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 and 3.5 mg/l) and BAP (1 mg/l) concentrations using broccoli root tip and leaf cutting. The results showed that a higher callus weight was found in the cultured leaf cutting than in root tip cutting in the concentration of 1.0, 1.5 & 2.0 mg/l IBA + 1.0 mg/l BAP combination. The highest callus weight was found in the cultured leaf cutting than root tips cutting at the concentration of 1.5mg/l IBA+1.0 mg/l BAP. Furthermore, the highest inverted sugar and glucose, chlorophyll and nutrient content (K+, NO3- & Ca++), total phenol, flavonoid and total antioxidant were found in the concentration of 1.5mg/l IBA+1.0 mg/l BAP combination in both broccoli leaf and root cutting. The results seemed that it was best to use the combination of the IBA and BAP in the concentration of 1.0-2.0 mg/l and 1mg/l to regenerate root, leaf and callus cell proliferation of broccoli from the root tip and leaf cutting.

Optimization of the Media and Plant Growth Regulators for Clonal Propagation of Adansonia digitata L.: An Endangered Tree

This research carried out to evaluate the influence of different nutrient media, specifically Murashige and Skoog (MS), Anderson medium (AM), and Woody Plant Medium (WPM), in both liquid and semisolid forms, on the in vitro growth of shoots and roots in Adansonia digitata (baobab) using nodal segments as the starting explants. These media were supplemented with varying concentrations of two plant growth regulators, NAA (0.1-1.0 mg/l) and BAP (0.2-2.0 mg/l).The results of the study demonstrated that Adansonia digitata explants exhibited the highest increase in both the number and length of shoots when cultured on MS medium with a combination of NAA (0.3 mg/l) and BAP (0.5 mg/l) in a semisolid state. The average number of shoots reached 3.8±2.33, and their average length was 2.3±2.00 cm. Plantlets grown on MS medium exhibited well-developed leaves and shoots.Further experiments were conducted with in vitro shoots, exploring various concentrations of the auxin NAA and cytokinins BAP, TDZ, and KN on MS medium. The findings indicated that BAP and NAA were more effective in promoting shoot proliferation compared to the other tested hormones. The combination of BAP (0.5 mg/l) and NAA (0.2 mg/l) significantly improved the shoot proliferation rate, with the highest percentage (60.4%) and the greatest number of regenerated shoots (4.8±2.33) observed on MS medium.In contrast, plantlets cultured in both AM and WPM media displayed lower averages for shoot and root numbers and lengths compared to those grown on MS medium. The maximum number of roots (3.1±1.66) was obtained when MS medium was augmented with IBA at a concentration of 1.0 mg/l.Subsequently, the produced plantlets were gradually transferred to pots filled with a mixture of perlite and cocopeat in a 1:3 ratio and placed in a greenhouse for further growth.

The Effect of BAP and NAA Combination on Callus Induction of Aglaonema Siam Aurora Leaf Explants in Vitro

This research aims to determine the effect of the Naphthalene Acetic Acid and Benzyl Amino Purine combination on callus growth of Aglaonema Siam Aurora leaf explants and to determine the combination level at the most optimal concentration on the callus growth of Aglaonema Siam Aurora leaf explants. Observation variables included callus emergence time, explants percentage of formed callus, callus length, and explant life percentage. The explants that where used were the first young leaves explants from shoots that were opened, with 2x2 cut size. Results show that the addition of a NAA and BAP combination had an effect on . Combination of 1.2 ppm BAP + 1 ppm NAA treatment is the most optimum treatment for callus growth with a callus percentage of 87.5%, the callus start time at week 3, the average callus length is 0.77 mm and the percentage number of survived explants is 100%

Optimization of in vitro propagation of jamun variety Konkan Bahadoli

Micro-propagation is a vital technique for round-the-year clonal multiplication of plants. Jamun is anindigenous fruit tree with great pharmacological importance. Two explants viz., shoot tips and nodal explants were cultured from January to May. The shoot regeneration from nodal explants was tested using 6-benzyl amino purine (BAP; 1.0-4.0 mg l-1) and α-naphthalene acetic acid (NAA; 0-0.25 mg l-1), while rooting was investigated with NAA (0.5-2.0 mg l-1). Maximum explant establishment was recorded in May. The nodal explants showed better establishment response (50.0%) than shoot tips (40.7%). The maximum shoot regeneration (72.16%) and earliest evocation response from nodal segments (14.0 days) were obtained with combinations of BAP (2.0 mg l-1) and NAA (0.25 mg l-1). Silver nitrate (AgNO3 @ 3.0 mg l-1) enabled shoot proliferation. Maximum rooting occurred on the medium containing 0.5 mg l-1 NAA. The in vitro plants were hardened on the potting mixture of cocopeat (4): perlite (1): vermiculite (1).

Conservation and Large Scale Propagation of a Valuable Ornamental Aquatic Plant, Echinodorus argentinensis Rataj through Micropropagation

A protocol was standardized for large scale propagation through multiple shoot proliferation from the basal buds of Echinodorus argentinensis, an ornamental aquatic plant. Explants were treated for 15 minutes with commercial bleach (containing 0.825% Sodium hypochlorite as active ingredient) which was diluted with distilled water to a concentration of 15%; and were then dipped for a second in 100% ethanol to obtain axenic cultures. The axenic basal buds initiated shoot formation within a week when cultured on full strength Murashige & Skoog medium (MS medium) supplemented with 1.0 mg/l 6-Benzylaminopurine (BAP). Number of shoots produced per explant was maximum (2.5672 shoots per explant p< 0.05) on MS medium supplemented with 1.0 mg/l BAP. Shoots were elongated considerably in all the media tried for shoot multiplication and maximum elongation (2.87 cm, p< 0.05) of the in vitro developed shoots was observed on MS medium supplemented with 1.0 mg/l BAP in combination with 0.1 mg/l Naphthalene acetic acid (NAA). Root regeneration was observed on all the shoot regeneration media and the highest number of roots/shoot (3.4568 roots per shoot) was obtained on MS medium devoid of any kind of plant growth regulators. The plantlets developed in vitro were subjected to acclimatization procedure and were finally planted in the aquarium. The protocol is ready for commercialization.

A prospective insight into the reproduction of Sternbergia clusiana K. Gawl.: an endangered species

Sternbergia clusiana (SC) is a bulbous plant having an alluring ornamental flower, medicinal properties, and an endangered status due to climate-change ecology. However, the methods of propagation for conserving this notable species have been neglected. The main aim of this study was to evaluate the influence of plant growth regulators (PGRs) on SC regeneration by virtue of a asexual propagation method, with the intention of preserving this endangered species from extinction. In this regard, having collected the bulbs from a wild habitat, bulbs were cut in accordance with the chipping technique. Thereafter, pieces were treated with 6-benzylaminopurine (BAP) at 250, 500, and 1000 mg·L−1, 1-naphthaleneacetic acid (NAA) at 100, 250, and 500 mg·L−1, putrescine (PU) at 50, 100, and 200 mg·L−1, BAP and NAA combination, BAP and PU combination, and a control. Pieces were then transferred into primary and terminal growing media under laboratory and greenhouse conditions, respectively. Next, the number, length, width, and weight of bulbs were determined. The greatest bulb number (2.10 counts), bulb length (26.75 mm), bulb width (16.25 mm), and bulb weight (3.13 g) were observed in the PU treatments. In addition, the results showed that even though the treated bulbs with BAP and PU combinations had preferable performance generally, the results were inconsistent. Taken together, this research indicates that utilizing asexual propagation along with PGRs, in the proper dosage, can serve as a mechanism to protect the endangered geophyte from extinction in nature.

El rol del AIA y BAP en la regeneración y formación de brotes in vitro de tres variedades de fresa (Fragaria x ananassa Duch.)

The objective was to determine the response of three strawberrry varieties (Fragaria x ananassa Duch.) to the aplication of two plant growth regulators: indol acetic acid (IAA) and 6-Benzyl aminopurine (BAP) added to Murashige & Skoog médium in strawberry micropropagation. The complete randomized block design was used and three strawberry varieties ‘Aromas’, ‘Albion’ and ‘Camarosa’ were considered as trials. MS medium for shoot regeneration in initial stage was supplemented with BAP 0.5 mgL-1 and IAA 0.6 mgL-1. Shoot proliferation MS medium was supplemented with BAP 0.5 mgL-1 in multiplication stage and MS medium hormone free was used for rooting induction. It was determined that after 32 days of cultivation the combination of IAA and BAP significantly affected shoot regeneration of apical shoot tips of three strawberry varieties. The greatest effect was caused on ‘Camarosa’. In addition, results on shoot multiplication using BAP indicated that ‘Albion’ performed better in shoot proliferation in terms of shoots per explants reaching 2.51 compared to ‘Camarosa’ and ‘Aromas’ with significant differences. However rooting medium with no growth regulators improves root development with best response of ‘Camarosa’ root length reaching 4.76 cm.

Enhanced immunoprotection against Acinetobacter baumannii infection: Synergistic effects of Bap and BauA in a murine model

BackgroundThe rise of multi-drug resistant Acinetobacter baumannii poses a grave threat to hospital settings, resulting in increased mortality rates and garnering global attention. The formation of biofilms facilitated by biofilm-associated protein (Bap) and the iron absorption capabilities mediated by Baumannii acinetobactin utilization A (BauA) contribute to the persistence and survival of multidrug-resistant strains. In this study, we aimed to investigate the potential of disrupting the function of BauA and Bap simultaneously as a strategy for controlling A. baumannii. MethodsRecombinant Bap and BauA were expressed, purified, and subcutaneously administered individually and in combination to BALB/c mice. Subsequently, mice were intraperitoneally challenged with A. baumannii, and the bacterial load and tissue damage in the spleen, lung, and liver were assessed. Serum samples were evaluated to determine antibody titers in surviving mice. ResultsSpecific IgG antibodies were significantly increased. A combination of the antigens resulted in enhanced titer of specific IgGs in comparison to either BauA or Bap alone. The antibodies remained stable over a seven-month period. The combination of Bap and BauA exhibited superior immunoprotection against A. baumannii infection compared to individual administration, resulting in a further reduction in bacterial load in the liver, spleen, and lungs. The histopathological analysis demonstrated successful protection of the tissues against A. baumannii-induced damage upon administration of the two immunogens. ConclusionsThe combination of Bap and BauA has the potential to target a broader range of A. baumannii strains, including those expressing either Bap or BauA, thereby increasing its efficacy against a diverse array of strains.

Improvements in Protoplast Isolation Protocol and Regeneration of Different Cabbage (Brassica oleracea var. capitata L.) Cultivars.

Protoplasts are a versatile tool in plant biotechnology since they can be used for basic biological studies as well as for breeding strategies based on genome editing. An efficient protoplast isolation protocol is essential for conducting protoplast-based studies. To optimize the protoplast isolation protocol in cabbage (Brassica oleracea var. capitata L.), different enzyme solutions were tested for the isolation of leaf mesophyll protoplasts. In our experiments, the combination of 0.5% Cellulase Onozuka RS and 0.1% Macerozyme R-10 showed the best result. The optimized protocol proved suitable for the isolation of protoplasts from five different cabbage cultivars with yields ranging from 2.38 to 4.63 × 106 protoplasts/g fresh weight (fw) and a viability of 93% or more. After three weeks in culture, protoplasts from all of the tested cultivars formed micro-calli, but further callus growth and shoot regeneration depended strongly on the genotype and regeneration protocol used. For shoot formation, 1 mg/L BAP in combination with auxin 0.2 mg/L NAA showed the best results with a regeneration of 23.5%. The results obtained will contribute to the development of different applications of cabbage protoplasts and facilitate the breeding process of this important horticultural crop.

Synergistic immunoprotection by Oma87 and Bap against Acinetobacter baumannii sepsis model

Acinetobacter baumannii is the leading cause of nosocomial infection. A surface protein commonly known as biofilm associate protein (Bap) has been identified in a bloodstream isolate of A. baumannii. Bap of A. baumannii is involved in intercellular adhesion within the mature biofilm. Outer membrane protein Acinetobacter 87 kDa (Oma87) or β-barrel assembly machinery A (BamA) has been introduced as an immunogenic outer membrane protein via in silico reverse vaccinology. Current research examines the synergistic effect of immunization of mice with both recombinant proteins viz., Oma87 and Bap. Antibodies were raised to the proteins. The mice were challenged with A. baumannii ATCC 19606 and the bacterial burden was enumerated in the mice’s livers, spleens, and lungs followed by histological examination. IgG levels significantly increased, and a significant (p < 0.0001) difference was observed between bacterial burdens in the internal organs of the actively and passively immunized groups. Female BALB/c mice weighing 20–25 g, were divided into 4 groups of 14 mice each viz., control, Oma87, Bap, Oma87-Bap groups. The proteins were individually immunogenic, but the combination of both proteins had a synergistic protection property. This is further supported by the histological examination. Based on the results, the combination of Oma87 and Bap may be considered a promising vaccine candidate against A. baumannii .

In vitro Regeneration of an Endangered Medicinal Orchid Dendrobium crepidatum Lindl. &amp; Paxton through Protocorm like bodies.

A protocol for regeneration of an endangered medicinal orchid Dendrobium crepidatum was established mainly via indirect protocorm like body (PLBs) formation. The PLBs procured from in vitro growth cultures was assessed in ½ MS medium alone and in combinations with 6-Benzyl amino purine (BAP), Kinetin (Kn) and α-Naphthalene acetic acid (NAA). The calli were induced from longitudinally bisected segments of PLBs. The optimum percentage of callus was obtained in ½ MS medium supplemented with BAP (1.0 mg/l) and combination of BAP (1.0 mg/l) with NAA (0.5 mg/l), where 64.3% and 83.3% of callus was formed respectively. PLB formation was achieved when callus was transferred onto the respective combinations in ½ MS basal medium. The optimum percentage (91.6%) of PLBs were regenerated in the combination of BAP with NAA. These PLBs differentiated into intact plantlets about 3 cm in height and with 4-5 roots were transplanted into potting mixture with highest rate of 93.3% survival rate in a green house.

Conservation in Tissue Culture of Malacocarpus crithmifolius (Retz.) Fisch. C.A.Mey. - Relict Species from Mangyshlak

Malacocarpus crithmifolius is an endangered rare relict with small size populations grown in a limited area. The purpose of this study was to initiate in vitro and micro replication of Malacocarpus crithmifolius. The vegetative and reproductive explants and Murashige &amp; Skoog medium (MS) supplemented with different concentrations and combinations of cytokinin and auxins were used. The response reaction of different explants and the plant growth regulators' effects on shooting frequency, the number of shoots, callusogenesis, and rooting percent were investigated. Culturing generative explants on the MS medium containing 6-Benzylaminopurine (BAP) combined with indole-3-acetic acid (IAA) or indole-butyric acid (IBA) led to direct shoot regeneration. The bud mass appeared in the leaf axil under inflorescences after one week of cultivation on the initiated medium. The replication was reached by micro-cutting of induced additional shoots and 3-fold passaging them on the fresh mediums. The average multiplication result at MS with BAP in combination with 1-Naphthaleneacetic acid (NAA) or IAA composed 5.85 after three months of cultivation. In conclusion, the applicable explant and phytohormonal composition of nutrient medium for initiation and micropropagation of M. crithmifolius were developed.

In vitro sterilization and callus induction from Cananga odorata forma genuina steenis explants

Cananga odorata (ylang-ylang) is a plant with numerous uses, including ornamental use, traditional medicinal ingredient, as fragrance, and cosmetics. The high market demand for ylang-ylang essential oil needs to be supported by information on the in vitro process of callus formation to supports the secondary metabolites production without having to cut or harvest the trees so that biodiversity is maintained. The aims of this study were to analyze the explants sterilization method using sodium hypochlorite (NaOCl) solution that was most suitable for the ylang-ylang initiation, and to analyze the effect of BAP and NAA treatment on the formation of ylang-ylang callus. The design used is a completely randomized design. The methods used included the preparation, sterilization, and callus induction using a combination of BAP and NAA hormones with twenty four treatment combinations. The results are: the sterilization of explants with sodium hypochlorite (NaOCl) solution at a concentration of 20% (v/v) 10 minutes followed by a concentration of 15% (v/v) 20 minutes was able to produce sterile explants in as much as 67.5% of cases. At the callus induction stage, the highest score of callus formation in leaf explants was in media-23 (BAP 4 ppm plus NAA 5 ppm).

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).

Transverse thin cell layer (tTCL) technology: a promising tool for micropropagation of Centratherum punctatum Cass.

The present study describes an efficient protocol for the micropropagation of Centratherum punctatum Cass. through transverse thin cell layers (tTCLs). The effect of plant growth regulators (PGRs), thickness of tTCLs, and source of tTCLs were evaluated. The tTCLs of varying thickness (0.5 to 5.0 mm) were excised from 10-d-old leaf and 45-d-old node and cultured on Murashige and Skoog (MS) medium supplemented with various concentrations of PGRs (BAP, TDZ, KN; 0.1 to 2.0 mg L−1), alone or in combination with NAA (0.1 to 1.0 mg L−1) for shoot induction. The leaf and node tTCLs responded with direct shoot regeneration. A significant effect of thickness or width on shoot induction was observed. For leaf, 1.0-mm-wide and for node 2.0-mm-thick tTCLs showed a maximum response. MS medium supplemented with 1.5 mg L−1 TDZ and 1.0 mg L−1 BAP in combination with 0.2 mg L−1 NAA was found to be optimum for shoot induction from tTCLs of leaf (96% response with 41.5 shoots per explant) and node (87% response with 11.9 shoots per explant), respectively. Rhizogenesis was obtained when micropropagated shoots were transferred to half strength MS medium supplemented with various concentrations (0.25 to 2.0 mg L−1) of IBA. The rooted plantlets were eventually acclimatized and transferred to soil. The clonal fidelity assessment by SCoT markers of the mother plant and micropropagated plants revealed their genetic similarity. Chlorophyll content estimation indicated lower levels in in vitro plants, which increased to a comparable level to that of field-grown plants after 3 mo of acclimatization, showing absence of stress during acclimatization. The procedure described here is a promising tool for micropropagation of C. punctatum as it produces high-frequency healthy shoots from a minimum explant source.

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.

Regeneration of Raja (Musa AAB Group) and Kepok (Musa ABB Group) bananas on various stages of in vitro culture

Banana group can be divided into two groups based on their method of its utilization. Banana group that can be eaten immediately after ripening is called "dessert banana", e.g., Raja, while the group that needs particular processing before consumption is called "plantain banana", e.g., Kepok. This study aimed to compare the growth of Raja banana with Kepok plantain through experiments at three stages of the in vitro culture media: the shoot initiation, shoot multiplication, and plantlet acclimatization, also to compare the growth of Raja bananas with Kepok plantains in response to cytokinins BAP and TDZ at shoot multiplication stage. Planting material was in the form of rhizomes that was prepared with the same size. The experiment was performed using a completely randomized design. Results showed that Kepok plantain could adapt faster to the media condition than Raja banana; the phenomenon was evident in the growing speed of Kepok during shoot initiation stage. The proportion of the B genome did not show a direct effect on shoot induction at the multiplication stage or enlargement and organ formation at the acclimatization stage. Shoot induction at the multiplication stage depended more on the composition of the media used. The combination of BAP 3 mg L-1 and TDZ 0.01 mg L-1 in MS media produced the best shoot induction rate, and TDZ 0.01 mg L-1 in MS media had the highest shoot elongation rate.&#x0D; Keywords: banana, BAP, genome, PGR, plantain, TDZ

FIELD PHYTOPROTECTION OF Coffea arabica MOTHER PLANTS, DISINFECTION AND CALLOGENESIS INDUCTION

In Chiapas, Mexico, there are high-yielding coffee plants adapted to the local climatic conditions. The presence of microorganisms in the explants makes developing protocols for cloning these genotypes in vitro difficult. The objective of this work was to evaluate how field and in vitro microorganism management affected asepsis and the induction of callogenesis in leaf explants of agronomically important coffee plants. Drought-tolerant genotypes were obtained from aseptic explants and cell cultures using a participatory study, agronomic, and in vitro techniques. Five accessions (ITTGj 1-5) were selected from a 21-year-old Borbon cultivar. The present study was conducted over two flowering cycles, evaluating the effect of field management on explant asepsis on the first and the callogenic response caused by the culture medium, the transport solution, and the genotype, on the second. Sixty days before explant collection, biweekly applications of calcium polysulfide (10 % v v-1), copper oxychloride (2 g L-1), and Zingiber officinale extract (20 g L-1) reduced fungal contamination by 100 % and bacterial contamination by 90 %. Field explant transportation in 200 mg L-1 citric acid and ascorbic acid solution reduced oxidation in explants and in vitro cultures. Proembryogenic friable corns were formed with the combination of 4.4 µM BAP (6-benzylaminopurine) and 7.25 µM 2,4-D (2,4-dichlorophenoxyacetic acid) at 45 days of culture, with genotype four showing the best response. Field management was effective for the aseptic establishment of Coffea arabica cultures in vitro, and the combination of BAP and 2,4-D used was an appropriate growth regulator for the induction of callogenesis.