Zaheer-ud-din Khan Wolfgang Editor-in-Chief AZIZULLAH EDITORS PAKISTAN FOREIGN Zaheer-ud-din Khan Wolfgang BIOLOGICAL SOCIETY OF PAKISTAN EDITOR-IN-CHIEF Tasneem Farasat (LCU for Women, Lahore) (2025)

Editor-in-Chief AZIZULLAH Editors PAKISTAN FOREIGN Editor-in-Chief AZIZULLAH Editors PAKISTAN FOREIGN BIOLOGICAL SOCIETY OF PAKISTAN EDITOR-IN-CHIEF Tasneem Farasat (LCU for Women, Lahore)

2012

In vitro studies in Tagetes erecta (marigold) under auxins (IAA, NAA) and cytokinins (BAP, Kinetin) effect for callus formation by different explants

Temporal regulation of somatic embryogenesis in guava (Psidium guajava L

Somatic embryogenesis was induced in immature zygotic embryos of guava (Psidium guajava L.) at 10-weeks post anthesis using 2 -38 d pulses and continuous treatments with different concentrations (0.001 -3.0 mg l -1 ) of 2,4dichlorophenoxyacetic acid (2,4-D). Subsequent development of somatic embryo was observed by sub-culturing onto plant growth regulator (PGR)-free, full-strength Murashige and Skoog (MS) agar medium containing 3% (w/v) sucrose. The maximum responses were shifted gradually from 0.01 mg l -1 2,4-D (continuous or 38 d treatment), to 0.05 mg l -1 2,4-D (28 -18 d treatment), to 0.1 mg l -1 2,4-D (14 -12 d treatment) and, finally, to 0.5 mg l -1 2,4-D (10 -8 d treatment). The highest frequency of embryogenesis (68.8%) and embryogenic intensity (69.2 embryos per explant per culture), as well as moderate frequencies of convertible elongated and short torpedo-stage somatic embryos (15% and 42.9%, respectively), with the highest efficiency (27.5) achieved in the 8 d treatment compared to continuous treatment of zygotic embryo explants with 0.5 mg l -1 2,4-D in MS agar medium containing 3% (w/v) sucrose at both the induction and development phases. Cellular pools of total, free, conjugated, and bound forms of various polyamines (e.g., putrescine, spermidine, and spermine) showed slow increases in the presence of 2,4-D during the 8 d induction phase. This was followed by rapid increases immediately after sub-culturing explant tissue onto the PGRfree MS development medium. The concentrations of various polyamines declined gradually over time on MS development medium. The production, metabolism, and use of different forms of various polyamines at various times (d) after culture initiation correlated with their temporal regulation during the induction and development phases of somatic embryogenesis. Exogenous application of different polyamines during the induction phase resulted in slightly increased frequencies, intensities, and efficiencies of embryogenesis, but with no observable change in the frequencies of the various categories of somatic embryos. The present study indicated that the process of somatic embryogenesis in guava may be less sensitive to PGRs and was induced even in the continuous presence of 2,4-D. Furthermore, somatic embryogenesis in guava was temporally regulated as a function of the exogenous concentration of 2,4-D. In addition, the temporal regulation of somatic embryogenesis was also associated with high levels of production, metabolism, and use of cellular polyamines during the different phases. Hence, improvements in the process of somatic embryogenesis in guava could be regulated by timed applications of 2,4-D alone, or in combination with polyamines, thereby modulating endogenous levels of the latter.

Effect of exposure time and incubation period of various sterilants and antioxidants on the in vitro morphogenesis of guava explants

IOSR Journal of Agriculture and Veterinary Science, 2014

This experiment was carried out to investigate the effects of various surface sterilants and antioxidants during in vitro propagation of guava (Psidium guajava L.). Different sterilants and exposure time significantly affected survival in shoot tip explants. Maximum survival response (43.3%) was observed when shoot tips were exposed to 2% NaOCl followed by 0.05 % HgCl 2 and 4% CaOCl with 36.7 and 33.3 % survival respectively. Similarly 5 and 10 minutes exposure times were statistically at par with each other. The interaction between different sterilants and exposure time was non significant. As compared to soot tips explants, the effect of different sterilants on the survival of nodal explants was also significant. The highest survival response of 31.7% was shown by 0.05% HgCl 2 followed by 4% CaOCl and 2% NaOCl (29.2 and 26.7%) respectively. Similarly the response of different exposure times (5 and 10 minutes) in case of nodal explants was non significant. Among all anti oxidants and incubation periods applied, dark incubation of cultures for 24 hours was effective which eliminated (34.3%) browning followed by dip of explants in 75:50 mg l-1 citric acid and ascorbic acid (31.8%) while control was inferior to all and gave 11.7% browning elimination. Similarly the effect of antioxidants on type of explants (shoot tip and nodal explants) was also significant. The highest response of 37.8 % was recorded in shoot tip explants while in nodal explants it was 14.5% only. The inter action between antioxidants and explants types was also significant. In over all, the highest browning elimination of 55% was recorded in shoot tip explants when cultures were kept in dark for 24 hours. Whereas the most inferior results were shown by control treatments where only 6.7 and 16.7% browning was eliminated in tips and nodal explants.

Effect of selected amino acids and polyethylene glycol on maturation and germination of somatic embryos of guava (Psidium guajava L.)

Scientia Horticulturae, 2009

Evaluation of the efficiency of somatic embryogenesis in guava (Psidium guajava L

SUMMARY An embryogenic protocol for plant regeneration of guava (Psidium guajava L.) was established using 10-week post-anthesis, zygotic embryo explants. Somatic embryogenesis was induced on Murashige and Skoog medium (MS) containing 3% (w/v) sucrose, 0.8% (w/v) agar and various concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) by continuous treatment of the zygotic embryo explants. Somatic embryos appeared as globular structures at the end of the third week from culture initiation, and heart-shaped, cotyledonary-stage, and torpedo-stage embryos appeared within the next few weeks. The development of somatic embryos was asynchronous and showed five-to-seven discernible stages. Depending upon the response of the somatic embryos during their maturation, germination, acclimatisation, and encapsulation, they were grouped into one of three categories. The preferred type of somatic embryos (≥ 1.5 mm) were called the " elongated torpedo " (ET) category. The slightly less-preferred type of stomatic embryos (from 1.0 – 1.5 mm) were termed the " short torpedo " (ST) category. The least preferred types of somatic embryos, at the cotyledonary, heart-shaped, and/or globular stages of development (< 1.0 mm), were grouped into a third category designated " CHG ". The suitability and efficacy of various growth regulators and other treatments were assessed based on six different embryogenic parameters: (i) the frequency of embryogenesis; (ii) the intensity of embryogenesis, defined as the average number of somatic embryos produced per culture (" ANEPC "); (iii) the frequency of ET somatic embryos; (iv) the frequency of ST somatic embryos; (v) the frequency of CHG somatic embryos; and (vi) the overall efficiency of embryogenesis, defined as the potential of a treament to produce somatic embryos at the ET or ST stages, or at both stages of development, that could be converted into plantlets. In the present report, we found that 0.01 mg l –1 2,4-D gave the maximum frequency and intensity of embryogenesis. But the highest frequencies of ET and ST somatic embryos were produced on MS medium containing 3% (w/v) sucrose and 0.001 mg l –1 2,4-D, while CHG embryos were produced at the highest frequency on the same medium, but containing 0.5 mg l –1 2,4-D. It was difficult to calculate the most effective concentration of 2,4-D for somatic embryogenesis based on parameters (i) – (v) above. Hence, quantitative estimations of the efficiency of embryogenesis (sixth parameter) were imperative in order to analyse the potential of the different treatments. The highest efficiency of somatic embryogenesis was achieved by continuous treatment of 10-week post-anthesis, zygotic embryo explants with 0.01 mg l –1 2,4-D on full-strength MS agar medium containing 3% (w/v) sucrose. These somatic embryos matured normally on the same medium, and germinated well both on half-strength solid and in half-strength liquid MS medium containing 3% (w/v) sucrose. They grew in full-strength liquid MS medium with 3% (w/v) sucrose and showed maximum survival upon transfer to soil and hardening. Evaluations of the efficiency of somatic embryogenesis in guava, based on the six parameters defined above, have also helped us to understand and evaluate processes for high efficiency micropropagation in other species. C ommon guava (Psidium guajava L.; Family Myrtaceae) is a diploid species (2n = 22), but is known to exist as a triploid (2n = 3x = 33) in some natural and artificial forms with seedless fruit. Both self-and cross-pollination occur in P. guajava

Studies of the Ovule and Seed Development of Guar

1963

Guar (Cyamopsis tetragonoloba (L.) Taub.) appears to have great potential as a field crop because of its production of mannogalactan gum. The gum is produced in the seed and is located in the tissue surrounding the embryo. In legumes, the endosperm is commonly digested and absorbed during embryo development so that the mature seed consists only of a seed coat surrounding an embryo. The persistence of a foodstorage tissue in the guar seed is of botanical interest as well as of commercial significance. Therefore, the nature of the development of this food-storage tissue has been investigated. The problem being studied is the morphological development of the guar ovule and seed. Primary concern will be given to endosperm development. Certain aspects of the development of the female gametophyte late embryo stages, and associated parts of the seed are included to show their relationship to endosperm growth. Methods and Materials The plant material used in this study was Cyamopsis tetragonoloba cv. 'Texsel' obtained from the 1962 Guar Research Field Plot at the Purdue University Agronomy Farm. In preparation for sectioning the fresh material was killed and fixed in Randolph's Modified Navishin (Craf) solution (4). After killing and fixation, the material was dehydrated in an ethyl-alcohol to xylol series followed by infiltration with paraffin.

Investigation on the effects of guava (Psidium guajava L.) infusions on germination, root tips and meristematic cells of Latuca sativa

Anais da Academia Brasileira de Ciências, 2015

Guava (Psidium guajava L.) is a plant often employed in popular medicine. Recently several studies have alerted about the toxicity of substances present in medicinal plants, which can pose risks to the human health. In this sense, the present work aimed to investigate the phytotoxic, cytotoxic and genotoxic action of three guava varieties - Paluma, Pedro Sato and Roxa (&quot;purple&quot;) - on the plant test system Lactuca sativa L. Thus, macro- and microscopic evaluations were carried out for five infusion concentrations (2.5, 5.0, 10.0, 20.0 and 40.0 g.L-1) prepared from each variety. Distilled water was used as negative control. Chromatographic and spectroscopic analysis by HPLC-PAD indicated that the chemical composition of the infusion of Roxa is different than that of the infusions of the varieties Paluma and Pedro Sato. It was observed that seed germination and root growth in L. sativa exposed to infusions decreased with increasing infusion concentration, regardless of the te...

Induction of callus and somatic embryogenesis from cotyledonary explants of Parkia timoriana (DC.) Merr., a multipurpose tree legume

International journal of food, …, 2006

Trends in Biosciences Dheerpura Society for Advancement of Science and Rural Development A Fortnightly International Journal

Current Biotechnology, Mehpara, 2012

An efficient protocol for plant regeneration from protoplasts in Catharanthus roseus is reported. Hypocotylderived embryogenic callus was used as a source of protoplasts. The embryogenic suspension was established in liquid MS, added with 1.0 mg l -1 NAA and 1.0 mg l -1 BAP; and then suspension was treated with various enzymatic solutions either alone or in combinations. The cocktail of cellulase (2.0%), pectinase (1.0%), macerozyme (0.02%) and driselase (0.50%) showed maximum yield of protoplasts (37.25 ± 1.86a X 10 5 ) with highest viability (65.25 ± 3.26a). The yield (8.50 ± 0.42a X 10 6 ) and viable protoplasts number (70.18 ± 3.51a) was even more when sorbitol was added with above enzyme mixtures as osmoticum. In 0.50 mg l -1 NAA +0.50 mg l -1 2, 4-D containing medium, protoplasts divided well and maximum number of micro colony formation was noticed (13.33 ± 1.53a/Petriplate). The callus biomass (fresh weight) was, however low in protoplast derived embryogenic callus (PDEC) than in normal embryogenic callus (NEC). Biochemically, the protein, proline, sugar and enzyme activity level (CAT, SOD, GR and APX) were also higher in PDEC than in NEC. The protoplast derived somatic embryos latter germinated and regenerated into plantlets. The recovery period from 'protoplast to plantlet' was around 40 weeks in contrast to 16 weeks in normal somatic embryogenesis pathway.