Multiple Shoot Production Research Articles

Cost Effective Methods of in Vitro Multiple Shoot Production in Two Commercial Diploid Bananas of Kerala

Cost-effective methods for in vitro propagation of two commercial diploid bananas of Kerala, namely Musa (AB) ‘ Njalipoovan’ and Musa (AA) ‘ Nivedyakadali’ were carried out to reduce unit production cost. Sword sucker, peeper sucker and eye bud explants were found to be equally effective concerning the number of axillary shoots from a single explant in both cultivars. Sucrose 3.0 per cent and table sugar 2.0 per cent produced the maximum number of multiple shoots in Njalipoovan. In the case of Nivedyakadali, table sugar at 2.0 per cent recorded the maximum number of multiple shoots. Half strength of vitamins in full MS medium observed more multiple shoots in cv. Njalipoovan. Half a tablet of vitamin B complex (2.0mgl-1) in the medium resulted in more shoots in the case of cv. Nivedyakadali. Agar 0.7 per cent recorded a significantly higher number of multiple shoots per culture in both cultivars. The treatments involving different types of paper support (filter paper, brown paper and ordinary paper) in liquid media were inferior to agar 0.7 per cent treatment.

Improvement of Stevia rebaudiana Bertoni In Vitro Propagation and Steviol Glycoside Content Using Aminoacid Silver Nanofibers.

The food industry is interested in replacing artificial sweeteners with natural sugars that possess zero calories and carbohydrates and do not cause spikes in blood sugar levels. The steviosides leaves, synthesized at Stevia rebaudiana Bertoni, are 300 times sweeter than common table sugar. Stevia propagation is limited due to the poor viability of the seeds, the long time and low germination rate, and the poor rooting ability of vegetative cuttings. Because of this, an alternative biotechnological method for its reproduction is being studied, such as multiple shoot production through direct organogenesis using nanofibers, formed from a derivative of amino acid valine as a carrier of the biologically active agent silver atoms/particles (NF-1%Ag and NF-2%Ag). The stevia explants were cultured on a medium containing NF-1%Ag and NF-2%Ag at concentrations of 1, 10, 50, and 100 mg L−1. The NF-1%Ag and NF-2%Ag treatment caused hormetic effects on stevia plantlets. At low concentrations of from 1 to 50 mg L−1 of nanofibers, the stimulation of plant growth was observed, with the maximum effect being observed at 50 mg L−1 nanofibers. However, at the higher dose of 100 mg L−1, inhibition of the values of parameters characterizing plant growth was recorded. The presence of nanofibers in the medium stimulates stevia root formatting.

In-vitro development of Nauclea diderrichii (de Willd. & Th. Dur) Merrin liquid-M Smedia supplemented with benzyl amino purine (BAP) and naphthalene acetic acid (NAA)

The growth of plantlets in Temporary Immersion Bioreactor system (TIBs) relies on initial successful liquid phase transition process. The response of N. diderrichii explants was assessed in liquid-M Smedia with a view to mass produce its seedlings using TIBs. Seven treatments consisting (A) 0.0/0.0, (B) 0.0/0.1, (C) 0.1/0.0, (D) 0.2/0.1, (E) 0.3/0.2, (F) 0.4/0.3 and (G) 0.5/0.4mg/lBAP/NAA combinations were studied. Each group consist of seven replicates and group A without Growth Regulators (GR) serves as control. The results at 4 Weeks after Inoculation (WAI) showed that effects of the growth regulators were significant on shoot length and number of adventitious shoots while number of roots and leaves were closely related. Treatment E produced highest number of adventitious shoots (3.6) which was higher than 0.9 shoots from treatment G and closely related to others. Maximum number of leaves (16.6) was produced by treatment F followed by E (15.7) while the least (12) was obtained in treatment A. The highest number of roots (4.9) was obtained from treatments B, followed by E (4.3) with the lowest being recorded in C (2.43). Liquid MS medium supplemented with 0.3/0.2mg/lBAP/NAA shows some promise for plantlets generation for the purpose of multiple shoot production of N. diderrichii in TIBs.

Callus Induction and Micropropagation of Lilium candidum L. Using Stem Bulbils and Confirmation of Genetic Stability via SSR-PCR

Natural populations of Lilium candidum L. are remarkably affected by biotic and abiotic factors therefore there is a requirement to develop effective micropropagation protocol to provide mass production, multiplication and conservation of these plants. For this reason, this study was aimed to develop an efficient micropropagation method for multiple shoot production via somatic embryogenesis induced from L. candidum stem bulbils and also to determine the genetic stability of in vitro grown plants using SSR markers. The obtained results of this study are the first comprehensive reports including an investigation of genetic fidelity on somatic embryogenesis of L. candidum. After surface sterilization of bulbils, the calculated regeneration percentage of them was 89.5% and the callus induction was achieved using leaf segments of in vitro grown bulbils. The well formed somatic embryos were obtained from smooth whitish-yellow colored calli and these somatic embryos produced well formed healthy L. candidum seedlings with adventitious roots. All rooted seedlings were easily adapted to greenhouse conditions and the genetic stability of in vitro grown seedlings were determined by using SSR-PCR technique and it was calculated as 100%.

Effect of Cytokinins on In Vitro Propagation of Ajuga xylorrhiza Kit Tan (Critically Endangered), Endemic to Turkey

Ajuga xylorrhiza Kit Tan is a rare endemic perennial species growing in the stony habitats in Southeastern Anatolia region, Turkey. An efficient and reproducible protocol has been developed for micropropagation of endangered Ajuga xylorrhiza. Shoots were cultured on Murashige and Skoog (MS) basal medium, supplemented with various concentrations of 6-benzyl amino purine (BAP), thidiazuron (TDZ), and kinetin (Kin). The optimal shoot formation was with the medium containing 0.125 mg L−1 BAP (7.91 shoots per explant), and 0.25 mg L−1 Kin (4.9 shoots per explant) was recorded. The best result in terms of shoot length (3.43 to 3.63 cm) was obtained from the Kin treatments. Kin parameters were more effective on shoot length and multiple shoot production than BAP and TDZ. For rooting, regenerated shoots were transferred to 1/4 strength MS medium containing two different concentrations of indole acetic acid (IAA) and α-naphthalenetic acid (NAA) at 0 (control), 0.5, or 1.0 mg L−1.The best results in terms of the number of roots per shoot were obtained from the medium supplemented with 0.5 mg L−1 IAA (3.10 roots per explant). Rooted plantlets were transferred to soil for acclimization with 100% success rate.

Effect of Different Carbon Sources on in vitro Shoot Regeneration and Multiplication of Cissampelos pareira (L.) - An Important Medicinal Plant

An efficient in vitro protocol for shoot regeneration and production of multiple shoots of Cissampelos pareira (L) was developed. In the present study, the effect of different carbon sources, sucrose, fructose, maltose and glucose was investigated on in vitro shoot regeneration by using axillary bud of Cissampelos pareira (L). The frequency, growth and multiplication rate were highly influenced by the type and concentration of carbon sources used. The highest number of shoots (8.06±0.11) was observed on MS medium supplemented with 2% fructose and along with BAP 1.0mg/l and NAA 0.5mg/l and regeneration frequency 95%. The least number of shoots were obtained on MS medium supplemented with 4% maltose and (3.4±0.10) shoots and glucose (3.26±0.11). Among the different carbon sources used in the present study, fructose 2% proved to be a better choice for multiple shoot regeneration followed by Sucrose, maltose, and glucose from axillary bud explants of Cissampelos pareira. In vitro shoots were then excised from the shoot clumps and transferred to the rooting medium containing NAA, IBA (0.5-3.0mg/l). The well-rooted plantlets were then separated from the culture tubes and transferred into sterile soil and vermiculate (1:1) in the greenhouse. Finally, the hardened plants were transferred to the field environment for utmost survivability.

Production of bioactive compounds in cladode culture of Turbinicarpus valdezianus (H. Moeller) Glass & R. C. Foster

This study aimed to establish an in vitro propagation method for the large-scale cultivation of Turbinicarpus valdezianus and to examine the content of bioactive compounds, as well as the antioxidant and cytotoxic activities of cladodes regenerated in vitro. The ideal combination for multiple shoot production from the bottom, middle and top regions of the cladode explants was 2 μM KN with 1 μM IBA. The explant obtained from the middle part of the cladode produced a higher number of shoots (10.9) than the bottom (7.2) and top (6.8) regions. The highest ex vitro rooting percentage (96.1%) was observed on vermiculite moistened with MS basal salts solution containing 1.0 μM IBA. A total of nine major lipophilic metabolites were simultaneously determined in the cladode tissues of T. valdezianus by LC-MRM-MS. Seven fatty acids were identified in the cladode tissues of T. valdezianus by GC-FID and GC–MS. The most abundant lipophilic metabolite and fatty acid in the cladode tissues were α-tocopherol (31.51 μg g−1 FW) and linoleic acid (43.29%), respectively. The methanolic cladode extract of T. valdezianus exhibited strong antioxidant and antitumor activity. This in vitro organ culture method is an alternative method to obtain various bioactive compounds from rare and slow growing T. valdezianus.

Enhanced In Vitro Shoot Multiplication of Piper sarmentosum by Suppression of Apical Dominance

An efficient micropropagation protocol has been developed through nodal explant by suppressing apical dominance for the enhanced production of multiple shoots by the physical method for the first time in Piper sarmentosum. Shoot regeneration was induced from the nodal explant on MS medium supplemented with varying concentrations and combination of different cytokinins (BA, KIN, and 2-ip) and auxins (IAA, IBA, and NAA). Of the different cytokinins used, higher number of the shoots (6.23 ± 0.13) and the higher shoot length (6.27 ± 0.17 cm) were observed on MS medium with 4.44 µM BA. But a remarkable increase in multiple shoots produced when suppressing the apical dominance by the physical method in the optimal concentration of 4.44 µM BA was observed, and this is the first report in tissue culture study. Rhizogenesis was observed on MS medium supplemented with IBA 4.9 µM and plantlets so obtained were hardened and the plant was established successfully on the natural environment with the survival rate of 89.68%. The present protocol suggests that by suppressing the apical dominance through the physical method without any expensive chemicals in the tissue culture system, shoot regeneration percentage can be increased, so we can adopt this method in tissue culture system for the production of a huge number of plants having strong apical dominance.

Multiplication of Bharangi—Clerodendrum serratum (L.) Moon

Aim: To develop effective in vitro multiplication protocol for rare and endangered medicinal plants of Clerodendrum serratum (L.) Moon. Materials and methods: Trials were carried out using nodal segments as explants, which were inoculated on Murashige and Skoog medium (MS) plain medium and different concentrations of phytohormones viz., benzylaminopurine (BAP), kinetin (Kn), indol-3-butyric acid (IBA), indol-3-acetic acid (IAA), and naphthaleneacetic acid (NAA), and incubated for 8 hours of photoperiod using cool- white fluorescent tubes with a light intensity of 3,000 lux at 22°C + 2°C. Results: The maximum (7.0 ± 0.045) numbers of shoots were developed from the nodal segment inoculated on MS fortified with BAP (4 mg/L) ± 0.1 % polyvinylpyrrolidone (PVP) with shoots of 1.72 ± 0.018 cm height. Auxin BAP at 4 mg/L proved to be effective for bud proliferation and production of multiple shoots. The best and early root induction was achieved on MS + IBA (1–4 mg/L). Conclusion: The developed in vitro protocol would be beneficial for the fast multiplication of bharangi plants and help to minimize the burden on supply and demand, so that the huge demand for the drug is fulfilled and also helpful to protect the plant.

In Vitro Multiple Shoot Induction and Plant Regeneration from Male Ephedra foliata: A Potential Medicinal Gymnosperm

Ephedra foliata Boiss. Ex. C.A. Mey, known as soma plant according to ancient Indian Ayurvedic system. It is known for its potential to cure many diseases. Review of literature revealed that E. foliata contains traces of alkaloids responsible for its therapeutic activity. In present study effect of different concentrations of plant growth regulator on nodal sector explants was checked for multiple shoot production. Maximum numbers of shoots were observed on Kinetin (2.5 mg/l) whereas, Kinetin (2.5 mg/l) with Indole acetic acid (2.5 mg/l) induced 9.04 ± 0.8 shoots in 22.46 ± 0.57 days and percentage of explants that showed response was more than any other combination. Out of the two plant growth regulators used for root induction from in vitro grown shoots 1-napthaleneacetic acid showed better response than indole-3-acetic acid.

In vitro regeneration, production, and storage of artificial seeds in Ceropegia barnesii, an endangered plant

Approaches for in vitro regeneration and fabrication of synthetic seeds were formulated to support restoration in the wild and genetic manipulation of Ceropegia barnesii (categorized as endemic and endangered). MS medium augmented with 4 mg L−1 benzyl adenine was most advantageous for the production of multiple shoots from nodal explants. Fabrication of synthetic seeds was accomplished by sodium alginate encapsulation of nodes from microshoots. The most favorable medium combination for the induction of multiple shoots from synthetic seeds was MS medium complemented with 4 mg L−1 benzyl adenine and 1 mg L−1 gibberelic acid. Following root induction promoted by half strength MS basal medium augmented with indolebutyric acid, multiple shoots were subjected to hardening. Influence of vesicular-arbuscular mycorrhizal fungi on the hardening trials was investigated and it was observed that dual inoculation of Glomus aggregatum and G. intraradices enhanced the survival rate. The encapsulated nodes of C. barnesii were tested for their capability to endure different temperatures during storage and the optimal temperature for storage was found to be 4°C. A methodology for initiation of somatic embryogenesis from C. barnesii is also reported here, but embryos could not be induced to develop further. The micropropagated plants were reintroduced in to their natural habitat. This is the first report on micropropagation of C. barnesii.

Micropropagation in litchi: concept, constraints and recent advances – a review

Owing to the genetically diverse nature of seedlings produced, seed propagation in litchi is not advisable. Furthermore, the long juvenile phase of seed propagated plants accompanied with the tendency of irregular bearing makes this method of propagation uneconomical and inefficient. Conventionally litchi is propagated by vegetative means like air layering, which again are slow and inefficacious. Hence use of micropropagation for large scale production of litchi plants can prove to be a more potent alternative. Albeit, till date only marginal success could have been achieved in in vitro regeneration of litchi, various studies have shown that micropropagation indeed can be used in litchi with varied rate of success. In past few years, encouraging results have been reported in regenerating plantlets from callus culture derived from young leaf explants on MS media. Some studies have shown production of multiple shoots by using nodal explants of 3-4 year old litchi on woody plant medium. Embryo culture in litchi has reportedly been successful by utilizing immature embryos of different sizes and age in a range of different media and achieving multiplication through induction of adventitious buds from embryonic shoots. Multiple shoots have also been obtained by direct germination of litchi seeds in liquid MS media. Attempts involving induction of somatic embryogenesis in cultures of zygotic embryos of litchi and anther culture have also been reported. Like other woody perennials secretion of polyphenols is also a major constraint in litchi micropropagation. In order to combat this problem, antioxidants like ascorbic and citric acids, in the growth media have been used by some workers with varied degrees of efficacies. Another serious problem affecting the success of micropropagation in litchi is the fungal infection, to inhibit the growth of which use of Bavistin and elimination of organic nutrients from growth medium have been tried. In this communication, we aim to critically analyze the major issues that are restraining the use of micropropagation in litchi along with the recent advances made in this field and also to investigate its future implications.

Effect of gamma ray irradiation and ethyl methane sulphonate onin vitromutagenesis ofCitrullus colocynthis(L.) Schrad

In the present study in vitro mutagenesis was used to study the effect of gamma irradiation and EMS on callus induction, morphogenesis and production of multiple shoots from different explants of Citrullus colocynthis (L.) Schrad. Gamma radiations (5 kR to 20 kR) and certain chemicals have been effected on plant growth developments and changes of biochemical metabolisms in plants. Murashige and Skoog (MS) medium containing with auxins such as NAA, IAA, 2,4-D (0.5 ~ 2.0 mg/l), cytokinines BAP, kn TDZ, (0.5 ~ 2.5 mg/l), L-Glutamic acid (1 ~ 2 mg/l) and Coconut milk (10 ~ 20%). After 5 weeks on induction media, explants and callus (EC) were exposed to 5 kR, 10 kR, 15 kR and 20kR, of gamma radiation and treated with 1, 2, 3, 4 and 5 mM ethyl methane sulphonate (EMS) for 30 min. The highest percentage of callusing was observed (70%) stem irradiated with 5 kR and significantly decrease in fresh and dry weight of callus in the below 4 kR doses and above 20 kR doses, there was a progressive decrease in the fresh weight and dry weights when compared to control callus. Maximum percentage of plantlet regeneration (59%) was induced from callus exposed to 15 kR gamma irradiation on MS media fortified with 2.0 mg/l 2,4-D + 2.0 mg/l BAP + 2.0 mg/l L-glutamic acid. Increase in gamma irradiation dose above 15 kR and 5 mM EMS reduced regeneration capacity of callus. Doses higher than 20 kR and 7 mM EMS was lethal to micropropagated plants of Citurullus colocynthis.

Highly competent in vitro propagation of Thrixspermum japonicum (Miq.) Rchb.f., a rare epiphytic orchid

An efficient protocol for asymbiotic seed germination and multiple shoot production of Thrixspermum japonicum has been established. Seeds were cultured on MSB (Murashige and Skoog, (MS) macro- and micro-nutrients, 0.1% (w/v) activated charcoal (AC), and 3.0% (w/v) sucrose) medium fortified with different concentrations of coconut water (CW), indole-3-acetic acid (IAA), or α-naphthaleneacetic acid (NAA), and gibberellic acid (GA3) to promote seed germination. The highest seed germination percentage (88.1%) was observed on MSB medium fortified with 0.2% (v/v) CW, 0.2 mg L−1 NAA and 0.5 mg L−1 GA3. Optimized shoot induction (94.3%) and maximum shoot numbers (8.3) were obtained on protocorm cultured on MS medium amended with 0.1% (w/v) AC, 3.0% (w/v) banana pulp, 2.0% (w/v) potato homogenate, 0.3 mg L−1 KN, 0.2 mg L−1 NAA, and 0.5 mg L−1 GA3. Rooting of the shoots was best achieved on MS medium supplemented with 0.1% (w/v) AC, 3.0% (w/v) banana pulp and 2.0% (w/v) potato homogenate, and 0.8 mg L−1 indole-3-butyric acid. Plantlets were acclimatized in the greenhouse with 88.1% survival rates. The protocol proposed in this study could be useful for conservation of S. japonicus, an important and rare epiphytic orchid.

Shoot Induction from Axillary Shoot Tip Explants of Fig (Ficus carica) cv. Japanese BTM 6.

Fig, or Ficus carica, is a fruit tree from the Moraceae family and is widely grown in tropical and subtropical regions of the world. Fig plants are mainly propagated through grafting, air layering, and hardwood cutting whereby these methods were found to be less efficient. Plant tissue culture is efficient method to propagate plants, particularly to produce true-to-type platelets for mass multiplication. The aim of this study is to induce multiple shoot formation on Ficus carica cv. Japanese BTM 6 through identifying and optimising the concentrations of 6-Benzylaminopurine (BAP) and Zeatin suited for shoot formation. The axillary shoot tip explants were cultured in MS media supplemented with different concentrations of BAP and Zeatin (0, 0.5, 1.0, 1.5 and 2.0 mg/L) to determine the optimal concentration for the formation of multiple shoots. Number of shoots per explants and the differences in shoot height of explants were calculated after 8 and 12 weeks of culture respectively. Of all the treatments of BAP, MS media containing with 2 mg/L BAP marked the highest number of shoots per explant with the average value of 1.67 ± 0.33 while 1.5 and 2 mg/L of BAP produced the highest differences in shoot height with 0.51 ± 0.08 cm and 0.51 ± 0.07 cm after 12 weeks respectively. Murashige and Skoog (MS) media supplemented with 2 mg/L Zeatin showed the highest production of multiple shoots and differences in shoot height with the average of 0.83 ± 0.219 and 0.32 ± 0.04 cm respectively among all the different treatments of Zeatin. In this study, BAP performed better in shoot induction and elongation as compared to Zeatin for the cultivar Japanese BTM 6.

Influence of seed position within the fruit on seedling quality and in vitro shoot tip production of jackfruit

ABSTRACTThis study reports on the influence of seed position within the fruit and shoot development on the production of jackfruit in vitro. Seeds were extracted from the different sections in the fruit and shoot tips excised from the resultant seedlings. The tips were cultured in vitro on media supplemented with 6-benzylaminopurine (BAP) or thidiazuron (TDZ). The seeds from the middle and basal sections of the fruit were larger and produced larger seedlings than those from the top. Seeds from the basal position took 10 days to germinate and produced seedlings 11 cm tall with four or five leaves. Partially covered and fully open shoots from 6–8 week-old seedlings performed best. The highest frequency of shoot induction (100%) and multiple shoot production (7.31 ± 1.2) with a mean length of 3.6 ± 0.13 cm was observed on Murashige and Skoog (MS) media supplemented with 3.0 mg/L BAP. Driver and Kuniyuki (DKW), and MS media were equally effective in shoot multiplication. More than 80% of the rooted plants survived culture, indicating that this technology could be used to conserve wild germplasm.

Micropropagation and Subsequent Enrichment of Carotenoids, Fatty Acids, and Tocopherol Contents in Sedum dasyphyllum L.

A promising micropropagation protocol has been systematically established and demonstrated for the enhanced production of carotenoids, tocopherol and fatty acids in shoot tissues of Sedum dasyphyllum. Shoot tip explants were grown on Murashige and Skoog (MS) medium. Different concentrations of N6-benzyladenine (BA) or thidiazuron (TDZ) alone or in combination with α-naphthaleneacetic acid (NAA) were tested in order to stimulate multiple shoot production. Ideal shoot induction (100%) and maximized shoot numbers (36.4) were obtained on explants cultured on media incorporated with 2 μM BA and 1 μM NAA combinations. The in vitro-developed shoots rooted best on half-strength MS media incorporated with 2 μM indole 3-butyric acid. Plantlets were effectively acclimatized in the greenhouse with 100% survival rate. The composition and contents of bioactive compounds such as carotenoids, tocopherol and fatty acids in shoot tissues of S. dasyphyllum were investigated using HPLC and GC-MS. The most abundant carotenoid in the shoot tissue was all-E-lutein (40.3–70.5 μg g−1 FW) followed by 9′-Z-neoxanthin (5.3–9.9 μg g−1 FW), all-E-violaxanthin (4.4–8.2 μg g−1 FW), and all-E-β-carotene (1.6–3.6 μg g−1 FW). The α-tocopherol contents of in vitro-raised shoots was 6.5-fold higher than shoots of greenhouse-grown plants. The primary fatty acids found in shoot tissues were α-linolenic acid (32.0–39.3%), linoleic acid (27.4–38.2%), palmitic acid (13.3–15.5%), and stearic acid (5.2–12.2%). In all, summarizing the findings, the micropropagated S. dasyphyllum showed significant enrichment of valuable bioactive carotenoids (92.3 μg g−1 FW), tocopherols (14.6 μg g−1 FW), and α-linolenic acid (39.3%) compared to their greenhouse counterparts. The protocol demonstrated here could be applied for the mass propagation and production of enhanced bioactive compounds from S. dasyphyllum with credibility.

In vitro production of banana plantlets and their validation at hill valleys

Performances of tissue cultured (TC) plantlets of BARI Kola-3 and BARI Kola-4 were evaluated against transplanting of conventional (CON) sucker at hill valleys during July 2011 to December 2014. The plantlets were produced at Biotech Lab, BARI Gazipur and validation trial was conducted at Ramgarh, Khagrachari hill district during March-April and September-October planting seasons (2011-14). Murashige and Skoog (MS) basal medium supplemented @ 3 mg 1-l and 5 mg l-1 BAP showed the best performance for multiple shoot production in BARI Kola-3 and BARI Kola-4, respectively. Both the varieties produced well developed roots in ½MS medium supplemented @ 0.5 mg 1-l IBA. Among the plantlets 98.5% plantlets were survived when hardened 7 days under polyethylene tunnel after 5 days hardening at room temperature but 100% plantlets died when transplanted plantlets were kept in open conditions at the nursery. 45 day - old healthy plantlets were planted at hill valleys in September-October and April-May planting seasons. BARI Kola-3 produced the highest 45.67 and 44.05 t ha-1 bunch yield at April-May and September-October planting, respectively. The highest 55.89 t ha-1 bunch yield was recorded from TC BARI Kola-4 in March-April planting followed by 49.67 t ha-1 in September-October Planting. TC BARI Kola-3 and BARI Kola-4 produced 3.68 and 12.52% higher yields in March-April planting, respectively than September-October planting. In case of planting materials, TC BARI Kola-3 and TC BARI Kola-4 produced 23.43 and 20.33% higher yield over CON suckered plant in March-April planting. On the other hand, TC BARI Kola-3 and TC BARI Kola-4 also produced 12.34 and 9.35% higher yield than CON Suckered plant in September-October planting. Similarly, TC BARI Kola-4 produced 28.33% higher yield than CON suckered BARI Kola-4 in March-April planting. In every case, TC plants showed better performances than the CON suckered plant.SAARC J. Agri., 15(1): 67-76 (2017)

Effects of plant growth regulators on multiple shoots regeneration of in vitroChrysanthemum morifoliumRamat

This study aimed to compare effects of different plant growth regulators on multiple shoot production of Chrysanthemum morifolium Ramat. Nodal segments and shoots of chrysanthemum were cultured on (a) Murashige and Skoog (MS, 1962), (b) MS supplemented with benzylaminopurine (BAP), (c) MS supplemented with BAP and indole acetic acid (IAA), (d) MS supplemented with IAA and BAP, (e) MS supplemented with kinetin (Kin) and indolebutyric acid (IBA) in different concentrations. The shoot cultured on MS supplemented with 0.5 mg L-1 BAP showed the highest multiple shoots (4.91 shoots segment-1). Micropropagation using shoots is the most desirable and safe technique, as it does not only minimize genetic variation but also helps in the formation of healthy shoots. It also provides high rate of multiplication. The seedlings induced from shoots cultured on modified ½MS supplemented with activated charcoal showed higher growth rate than the shoots cultured on modified ½MS without activated charcoal.

Effects of the exogenous polyamines on micropropagation of cherry rootstocks

In the present study, the effects of the 3 polyamines (PAs); putrescine (put), spermidine (spd) and spermine (spm) on micropropagation in CAB-6P, Gisela 6 and MxM 14 cherry rootstocks were investigated. In CAB-6P, shoot number (1.5) and shoot multiplication percentage (50%) were highest with 1 mg/l spd whereas shoot length was maximum with put irrespective of concentration. In Gisela 6, 1 mg/l spd exhibited the maximum shoot number (2) and shoot multiplication percentage (55.56%). In MxM 14, none of the 3 PAs resulted in multiple shoot production, In CAB-6P, root number (4) and rooting percentage (45.45%) were highest with 1 and 2 mg/l put, respectively, whereas 1 mg/l spd resulted in the greatest root length (160 mm). In Gisela 6, 2 mg/l put enhanced root number and root length, whereas rooting percentage was diminished by all 3 PAs. In MxM 14, root number (6.33) and rooting percentage (100%) were greatest with 1 mg/l put and 1 mg/l spm, respectively. In all 3 cherry rootstocks, PAs did not augment chlorophyll content. In CAB-6P, PAs resulted in reduction of leaf carbohydrate and proline levels and activation of mechanism of osmoregulation and osmotic adjustment in leaves. In Gisela 6, leaf carbohydrate levels were raised with 0.5 mg/l spm or 1 mg/l spd. Among the 3 PAs, only spd raised leaf proline content, while the content in roots was increased by 1 mg/l put, showing that PAs cause some kind of stress to the explants. In MxM 14, spd and spm augmented leaf carbohydrate levels, while in roots, only spm at 0.5 mg/l increased carbohydrate content. PAs hardly affected root proline content. It seems that in Gisela 6 and MxM 14, spd and spm increase the leaf carbohydrate content, whereas in CAB-6P all 3 PAs led to depleted leaf carbohydrate levels. The different responses among the 3 cherry rootstocks to PAs concerning shoot and root attributes are genotype-dependent.