Floral Organogenesis of Titanotrichum oldhamii (Gesneriaceae)

Floral organogenesis of Titanotrichum oldhamii (Hemsl.) Soler., the only species in the genus and endemic to East Asia, was observed under SEM. We found that the development of calyx, corolla and androecium belongs to pentamerous pattern. They come respectively from primordia of calyx, corolla and androecium, and all differentiated from the flower primordium. The zygomorphism of corolla and androecium is derived from quicker growth of the upper lip of corolla and delay in development of the staminode. Initiation of sepal primordia and their development are not consistent in order; the order of initiation is from adaxial central primordium, abaxial two primordia and finally lateral two primordia, while the order of development is first adaxial central sepal, lateral two and finally abaxial two. Sepals are valvate in flower bud. Initiation of corolla lobe primordia and their development are consistent in order, i.e. first abaxial central lobe (central lobe of the lower lip), lateral two (lateral two lobes of the lower lip) and finally adaxial two (two lobes of the upper lip). The aestivation of corolla is imbricate, and the order from outside to inside is the central lobe of the lower lip, lateral two of the lower lip, and finally two of the upper lip or lateral two lobes of the lower lip, two of the upper lip and central one of the lower lip. Stamen primordia are alternate to the corolla lobe primordia, with the anterior two primordia later than the posterior two in initiation; staminode primordium is simultaneous with the posterior two in initiation, but smaller, and opposite to the adaxial carpel (upper lip of stigma). Compared to the patterns of floral organogenesis of Rehmannia (Scrophulariaceae), Whytockia and Rhynchoglossum (Gesneriaceae), the present authors found that the floral organogenesis is diverse and does not form two distinct patterns among these four genera. Based on the results we tend to consider that the conventional demarcation between the Scrophulariaceae and Gesneriaceae using number of ovary locules (two vs one) and placentation (axile vs parietal) is questionable.

Floral Organogenesis and Development of Two Taxa in Tribe Hyoscyameae (Solanaceae)-Przewalskia tangutica and Hyoscyamus niger

Floral organogenesis and development of Przewalskia tangutica Maxim. endemic to China and Hyoscyamus niger L., which belong to the tribe Hyoscyameae (Solanaceae), were studied using scanning electron microscope. They have three common characters of floral organ initiation and development: 1) initiation of the floral organs in the two species follows Hofmeister's rule; 2) the mode of corolla tube development belongs to the 'late sympetaly' type; 3) primordia of the floral appendages initiated in a pentamerous pattern and acropetal order. But initiation of the calyx-lobe primordia showed different modes in these two species. The calyx-lobe primordia of H. niger have simultaneously whorled initiation, while those of P. tangutica have helical initiation, but the five calyx-lobe primordia form a ring after all five calyx-lobe primordia occur. The systematic significance of the present results in the genera Hyoscyamus and Przewalskia is discussed in this paper.

NECK LEAF 1, a GATA type transcription factor, modulates organogenesis by regulating the expression of multiple regulatory genes during reproductive development in rice

In the monocot rice species Oryza sativa L., one of the most striking morphological processes during reproductive development is the concurrence of panicle development with the sequential elongation of upper internodes （UPIs）. To elucidate the underlying molecular mechanisms, we cloned the rice gene NECK LEAF 1 （NL1）, which when mutated results in delays in flowering time, smaller panicles with overgrown bracts and abnormal UPI elongation patterns. The NL1 gene encodes a GATA-type transcription factor with a single zinc finger domain, and its transcripts are de- tected predominantly in the bract primordia, which normally degenerate in the wild-type plants. Overexpression of NL1 in transgenic plants often gives rise to severe growth retardation, less vegetative phytomers and smaller leaves, suggesting that NL1 plays an important role in organ differentiation. A novel mutant allele of PLASTOCHRON1 （PLAD, a gene known to play a key role in regulating leaf initiation, was identified in this study. Genetic analysis demonstrated an interaction between nil and plal, with NL1 acting upstream of PLA1. The expression level and spatial pattern of PLA1 were found to be altered in the nil mutant. Furthermore, the expression of two regulators of flowering, Hd3a and OsMADS1, was also affected in the nil mutant. On the basis of these findings, we propose that NL1 is an intrinsic factor that modulates and coordinates organogenesis through regulating the expression of PLA1 and other regulatory genes during reproductive development in rice.

MIKC^(C)-type MADS-box genes in Rosa chinensis: the remarkable expansion of ABCDE model genes and their roles in floral organogenesis

MIKC^(C)-type MADS-box(MIKC^(C))genes encode transcription factors that have crucial roles in controlling floral organogenesis and flowering time in plants.Although this gene family has been well characterized in many plant species,its evolutionary and comprehensive functional analysis in rose is lacking.In this study,58 non-redundant MIKC^(C)uni-transcripts were extensively identified from rose transcriptomes.Phylogenetic analysis placed these genes into 12 clades with their Arabidopsis and strawberry counterparts,and revealed that ABCDE model(including AP1/FUL,AP3/PI,AG,and SEP clades),and SOC1 and AGL6 clade genes have remarkably expanded in Rosa chinensis,whereas genes from the FLC and AGL17 clades were undetectable.Sequence alignments suggest that the AP3/PI clade may contribute to more specific functions in rose due to a high variation of amino acid residues within its MADS-box domains.A comparative analysis of gene expression in specific floral organ differentiation stages and floral organs between R.chinensis cv.Old Blush and the closely related mutant genotype R.chinensis cv.Viridiflora(floral organs mutated into leaf-like structures)further revealed the roles of ABCDE model genes during floral organogenesis in rose.Analysis of co-expression networks provided an overview of the regulatory mechanisms of rose MIKC^(C)genes and shed light on both the prominent roles of AP3/PI clade genes in floral organogenesis and the roles of RcAGL19,RcAGL24,and RcSOC1 in regulating floral transition in rose.Our analyses provide an overall insight of MIKC^(C)genes in rose and their potential roles in floral organogenesis.

In vitro Plant Regeneration from the Mature Tissue of Navel Orange (Citrus sinensis L. Osbeck) by Direct Organogenesis

An efficient in vitro regeneration system by direct organogenesis from mature nodal and internodal stem segments ofNewhall navel orange (Citrus sinensis L. Osbeck) was developed. Illuminating conditions together with plant growthregulators affected the adventitious bud regeneration frequency and efficiency. The initial 15 d darkness inoculation isbeneficial for the adventitious bud regeneration. The highest regeneration frequency (85.2%) and bud formationefficiency (3.7 per responsive internodal stem segment) were obtained in the media supplemented with 1.0 mg L-1 BAPand 0.5 mg L-1 NAA. ABA at 0.2 mg L-1 positively affected the bud formation efficiency, which amounted to 8.5 buds perinternodal segment in the presence of BAP at 1.0 mg L-1. The adventitious shoots successfully rooted and weretransferred to the soil.

Endogenous auxin and its manipulation influence in vitro shoot organogenesis of citrus epicotyl explants

Endogenous auxin is an important regulator of in vivo organ development,but its role in in vitro organogenesis is unclear.It has been observed that the basal end of epicotyl cuttings of juvenile citrus seedlings produces fewer shoots than the apical end.Here,we report that elevated endogenous auxin levels in the basal end of citrus epicotyl cuttings are inhibitory for in vitro shoot organogenesis.Using transgenic citrus plants expressing an auxin-inducible GUS reporter gene,we have observed elevated levels of auxin at the basal end of stem cuttings that are mediated by polar auxin transport.Depleting endogenous auxin or blocking polar auxin transport enhances shoot organogenesis.An auxin transport inhibitor,N-1-naphthylphthalamic acid(NPA),can also enhance shoot organogenesis independent of its action on polar auxin transport.Finally,we demonstrate that the promotional effects of depleting endogenous auxin or blocking polar auxin transport on shoot organogenesis are cytokinin-dependent.Our study thus provides meaningful insights into possible roles of endogenous auxin and polar auxin transport,as well as auxin–cytokinin interactions,in in vitro shoot organogenesis.Meanwhile,our results may also provide practical strategies for improving in vitro shoot organogenesis for citrus and many other plant species.

Somatic Embryogenesis and Organogenesis for Regeneration of Endangered Multipurpose Desert Plant <i>Leptadenia pyrotechnica</i>Forsk. Decne in the Kingdom of Bahrain

Leptadenia pyrotechnica is an important multipurpose endangered plant in the Kingdom of Bahrain with restricted distribution. Nodal explants were cultured on Murashige and Skoog (MS) medium supplemented with different concentrations and combinations of indole acetic acid (IAA) and 6-benzylaminopurine (BAP). Initially, 80% and 60% explants responded in direct shoot and callus initiation response respectively in presence of 8.88 μM BAP with 5.71 μM IAA in modified MS media after two weeks of culture. The highest frequency of plant regeneration was observed in presence of 8.88 μM BAP with 1.14 μM IAA following organogenic pathway of differentiation. Hundred percent callus proliferation was observed while initial callus developed in presence of 4.44 μM BAP with 2.85 μM IAA and was transferred in media containing 4.44 μM, 6.66 μM BAP with 2.85 μM IAA and 13.32 μM BAP with 5.71 μM IAA. The callus derived plants were regenerated following the pathway of indirect somatic embryogenesis. The induction of somatic embryogenesis and plant regeneration from callus was also observed in modified MS media supplemented with 4.44 μM BAP and 2.85 μM IAA. The plant regeneration protocol we developed for Leptadenia pyrotechnica will be very beneficial for biodiversity conservation and environment protection of Bahrain. Moreover, the present paper reports for the first time specifically the somatic embryogenesis in this multipurpose desert plant Leptadenia pyrotechnica.

Efficient Somatic Embryogenesis and Organogenesis of Self-Pollination <i>Artemisia annua</i>Progeny and Artemisinin Formation in Regenerated Plants

To enhance the understanding of artemisinin biosynthesis, we have successfully bred self-pollination Artemisia annua plants. Here, we report efficient somatic embryogenesis and organogenesis of self-pollination plants and artemisinin formation in regenerated plants. The first through sixth nodal leaves of seedlings are used as explants. On agar-solidified MS basal medium supplemented with TDZ (0.6 mg/l) and IBA (0.1 mg/l), all explants after inoculation of less than 3 weeks start to form embryogenic calli, which further produce globular, torpedo, heart and early cotyledon embryos. In all six positional leaves, explants from the sixth leaf show the rapidest responses to induction of embryogenic calli and somatic embryos. On this medium, somatic embryos continuously develop into adventitious buds, which can form adventitious roots on a rooting medium containing NAA (0.5 mg/l). Meanwhile, on agar-solidified MS basal medium supplemented with BAP (1 mg/l) and NAA (0.05 mg/l), approximately 100% of explants from leaves #3-6 form calli in less than 3 weeks of inoculation and adventitious buds via organogenesis in 3-4 weeks. In all six positional leaves, explants from the sixth leaf exhibit the rapidest response to induction of calli and adventitious buds. Nearly 100% adventitious buds can form adventitious roots on the rooting medium. Regenerated plants from both somatic embryogenesis and organogenesis complete self-pollination to produce seeds in 80-90 days of growth in growth chamber. LC-ESI-MS analysis demonstrates that regenerated plants biosynthesize artemisinin. These results show the highly efficient regeneration capacity of self-pollination A. annua plants that can form a new platform to enhance the understanding of artemisinin biosynthesis and metabolic engineering.

Endothelium-derived essential signals involved in pancreas organogenesis

Endothelial cells(ECs) are essential for pancreas differentiation, endocrine specification, and endocrine function. They are also involved in the physiopathology of type 1 and type 2 diabetes. During embryogenesis, aortic ECs provide specific factors that maintain the expression of key genes for pancreas development such as pancreatic and duodenal homeobox-1. Other unknown factors are also important for pancreatic endocrine specification and formation of insulin-producing beta cells. Endocrine precursors proliferate interspersed with ductal cells and exocrine precursors and, at some point of development, these endocrine precursors migrate to pancreatic mesenchyme and start forming the islets of Langerhans. By the end of the gestation and close to birth, these islets contain immature beta cells with the capacity to express vascular endothelial growth factor and therefore to recruit ECs from the surrounding microenvironment. ECs in turn produce factors that are essential to maintain insulin secretion in pancreatic beta cells. Once assembled, a cross talk between endocrine cells and ECs maintain the integrity of islets toward an adequate function during the whole life of the adult individual. This review will focus in the EC role in the differentiation and maturation of pancreatic beta cells during embryogenesis as well as the current knowledge about the involvement of endothelium to derive pancreatic beta cells in vitro from mouse or human pluripotent stem cells.

The Effect of Phytohormones on Lavender （Lavandula Angustiflia Mill.） Organogenesis

Lavender （L. angustifolia） is a genus of flowering plants in the mint family, Lamiaceae. It is an aromatic shrub with multiple stems growing 30 to 60 cm tall. It is native to Asia, Europe and Mediterranean regions and grows on hilly areas and coastlines. The evergreen leaves are narrow and long and covered in fine hairs, which normally contain the essential oils. The leaves are also pinnately toothed, or pinnate. The plant blooms between April and June, and flowers are purple produced on violet bracts. All parts of the plant have a strong and scented odor and a bitter taste. The flowers and leaves are used as an herbal medicine. Lavender essential oil is extracted by distilling flowers and leaves, Essential oil has higher levels of linalyl acetate （40%）, butyric acid, propionic acid, valeric acid, free linalool. Considering the lack of information about lavender tissue culture, the current experiment＇ was aimed to study the effect of phytohormones on lavender callus induction and organogenesis. The lavender explants （leaf and apical meristem） were cultured onto MS media supplemented with different phytohormones. According to the observations, 5 mg/L NAA and 5 mg/L KIN treatment caused leaf and root formation, which were originally derived t^om dense and green calli. The MS medium containing 5 mg/L IBA and 5 mg/L Kin was effective just on leafy explants so that explants formed into leaves after callus induction. Application of 5 mg/L NAA and 5 mg/L BAP on apical meristem explants produced shoot and root after callus induction. However, complete plants were produced after sub-culturing the samples. In conclusion, MS medium supplemented with 5 mg/L NAA and 5 mg/L BAP was selected as the best medium for lavender tissue culture.

Floral organogenesis of Delavaya toxocarpa (Sapindaceae; Sapindales)

The floral organogenesis and development of Delavaya toxocarpa Franch. （Sapindaceae） were studied trader scanning electron microscope and light microscope to determine its systematic position within Sapindaceae. Flowers arise in terminal thyrses. The sepal primordia initiate in a spiral （2/5） sequence, which are not synchronous. The five petal primordia initiate almost synchronously and alternate with sepal primordia. Eight stamens initiate almost simultaneously and their differentiation precedes that of the petals. The last formed petal and one stamen initiate from a common primordium. Mature stamens curve inwards and cover the ovary in bud. The gynoecium begins as a hemispheric primordium on which two carpellary lobes arise simultaneously. Later in development a single gynocium is formed with two locules and two ovules per locule. Floral morphology suggests a closer affinity with Sapindaceae, although certain features of floral ontogenesis are similar to those observed in certain members of the former Hippocastanaceae, such as Handeliodendron.

Micropropagation of loblolly pine by somatic organogenesis andRAPD analysis of regenerated plantlets

Organogenesis was induced in callus derived from mature zygotic embryos of six families (J-56, S-1003, E-22, E-311, E-440, and Mc) of loblolly pine (Pinus taeda L.) within 24 weeks of culture. Elongation of adventitious buds was achieved on TE medium supplemented with 0.5 mg·L?1 indole-3-butyric acid (IBA) and 1 mg/l 6-benzyladenine (BA). The most suitable medium for root formation proved to be TE medium supplemented with 0.5 mg·L?1 IBA, 2mg·L?1 BA and 0.5 mg/l gibberellic acid (GA3). 169 regenerated plantlets were transferred to a perlite: peatmoss: vermiculite (1∶1∶1) soil mixture, and 98 plantlets survived in the field. Total DNA was extracted from the needles of the regenerated plantlets of the six families of loblolly pine. Analysis of random amplified polymorphic DNA (RAPD) using 20 arbitrary oligonucleotide 10-mers, show that amplification products were monomorphic for all the plantlets of family J-56, S-1003, E-22, E-311, E-440, and Mc of loblolly pine. These results suggested that organogenesis can be used for clonal micropropagation of some families of loblolly pine.

Efficient Evergreen Plant Regeneration of Cinnamomum japonicum Sieb.through in vitro Organogenesis

Cinnamomum japonicum Sieb.is an excellent roadside tree and medicinal tree species with considerable ornamental and economic value.In this study,we successfully developed a large-scale micropropagation protocol for C.japonicum for the first time.Sterilized shoots were excised and used as explants for shoot induction on several basal media,supplemented with different concentrations of plant growth regulators(PGRs),such as Thidiazuron(TDZ),N^(6)-Benzyladenine(6-benzylaminopurine)(BA),α-naphthaleneacetic acid(NAA)and Gibberellic acid(GA_(3)).After comparison,the most efficient medium for shoot regeneration was 1/2 Murashige and Skoog(MS)medium containing 0.5 mg L^(-1)BA,0.05 mg L^(-1)NAA and 0.2 mg L^(-1)GA_(3),which resulted in an average number of induced shoots per explant and shoot length of 5.2 and 1.62 cm at 28 d,respectively.Then,elongated adventitious shoots were transferred to induce roots.86.7%of shoots was able to root on 1/2 MS medium supplemented with 0.5 mg L^(-1)NAA and 0.1 mg L^(-1)BA.The earliest rooting time observed was after 21 d and the average root length was up to 3.3 cm after 28 d.Our study shows that C.japonicum can be successfully regenerated through de novo organogenesis,which lays a foundation for future transformation research on this tree.

Organogenesis公司开展生物合成皮肤的人体试验

Organogenesis 公司(美国)终于在人体上进行了它的"活皮"移植实验,这种人造皮肤称为 Graftskin,用于治疗烧伤和创伤.I期试验正在西宾夕法尼亚医院进行.不过该公司避而不谈试验的详细内容.说是应美国食品及药物管理局的要求而保持缄默。很明显,

Direct OrgaNogenesis from Cotyledons in Cultivars of Citrus clementina Hort. Ex Tan

An efficient protocol to induce shoot buds regeneration in Citrus clementina cultivars (‘Monreal’, ‘SRA 63’ and ‘SRA 64’) by direct orgaNogenesis has been developed using cotyledons as explants. Cotyledons transversely cut in three segments and entire ones were cultured on Murashige and Skoog (1962) solidified medium containing vitamins, 500 mg l-1 malt extract, 50 g l-1 sucrose and supplemented with three different concentrations of BAP (8.8, 13.2 and 17.6 μM). In all three cultivars the entire cotyledons showed more shoot morphogenic potential than transversely cut ones and after 60 incubation days the optimum BAP concentration was 17.6 μM in ‘Monreal’ (50% ± 2.89% of frequency regeneration) and 13.2 μM in ‘SRA 63’ (33.33% ± 3.33%) and ‘SRA 64’ (25.93% ± 1.85%). In absence of BAP No mor-phogenesis occurred, demonstrating the absolute requirement of this hormone for shoots induction. The young shoots showed a regular growth in the culture tubes containing the basal medium without hormones, and the rooted plantlets survived after acclimatization. This protocol may find application in Citrus genetic improvement programs.

<i>In Vitro</i>Organogenesis of <i>Colocasia esculenta</i>cv. <i>Antiquorum</i>L.

In vitro organogenesis of an upland species of Colocasia esculenta cv. antiquorum L. was examined in relation to different explants like meristem and parenchymatous storage tissues with or without anthocyanin layer, four levels of each of Kn, 2,4-D, NAA and BAP and four incubation environments such as: 1) 16 h 3 Kl light intensity + 24°C ± 2°C;2) 24 h dark + 24°C ± 2°C;3) 24 h dark + 30°C ± 3°C and 4) 12 h diffuse light + 30°C ± 3°C. Only meristems showed proliferation with various degree of intensity both at 16 h 3 Kl light + 24°C ± 2°C and 24 h dark + 24°C ± 2°C conditions and poor response with different levels of Kn + NAA either in light or in the dark. Cultures with NAA + BAP were proliferated very quickly with very high degree of intensity. The cultures under dark did not proliferate for 20 days which upon transfer to light showed high degree of proliferation. Cultures with NAA + BAP formed calluses more pronouncedly at dark than that occurred in the light. Parenchymatous tissues with or without anthocyanin did not proliferate but the tissues with anthocyanin lost pigmentation after 25 - 30 days and turned to grey colour after 50 days while tissues without anthocyanin turned to green colour with shinny pimples indicating that protocorm may be developed. No culture under high temperature environment (30°C ± 3°C) neither survived nor proliferated. The meristems in culture were died within 15 - 20 days while others within 25-30 days. In conclusion, a combination of NAA (0.5 - 3.0 mg/l) and BAP (0.5 - 2.0 mg/l) and an incubation photoperiod of 16 h coupled with temperature of 24°C ± 2°C were found most suitable for in vitro culture of Colocasia esculenta cv. antiquorum L.

Morpho-Histological Analysis of Direct Shoot Organogenesis Induced in Flower Buds Cultures of <i>Allium altissimum</i>

The present work gives a detailed study of in vitro shoot organogenesis of the ornamental onion A. altissimum Regel from the buds of the middle layer of the inflorescences. The course of morphogenesis was examined by light and scanning electron microscopy. Histological observation revealed that during 3 - 5 days of culture on the BDS medium supplemented with 2.0 mg·L-1 of BA and 2.0 mg·L-1 of NAA the epidermal cells of the stamen filament in the area of its fusion with the tepal became competent and dedifferentiated. Originally the organogenesis involved several initial epidermal cells. The formation of meristematic centers was observed from day 3 to day 14. The apical shoot meristems and leaf primordia in a roller shape formed from day 14 to day 28 of culture on the same media. The further development of vegetative shoots and formation of the bulblets were observed when the explants were stimulated by triapenthenol (2.0 mg·L-1).

Floral Organogenesis and Ring Meristem in <i>Phytolacca</i>

To further study the floral organogenesis and discussing the floral origin of Phytolacca, the procedures of floral organogenesis were observed in Phytolacca esculenta and Phytolacca zhejiangensis. The results showed that the floral organogenesis was consistent in Phytolacca. Their sepals were 2/5 helix, and with counter-clockwise and clockwise, usually the first sepal located at non-median of abaxial side. The first sepal of Phytolacca esculenta was initiated at non-median of adaxial side. There was no evident relationship between sepal and stamen initiating position, and the stamens initiated on ring meristem, they initiated approximately at the same time, and when the androecium member was numerous, they initiated centrifugally, the outer stamen initiated irregularly. Carpel initiated alternately with inner stamens. And the carpels connected by septum, if the septum grew more, the carpel was syncarpous at morphology, otherwise the carpel was apocarpous at morphology. So the syncarpous and the apocarpous have no successively relationship on evolution. Ovule initiated inside the carpel and opposite to carpel. Androecium, carpel and ovule initiated at ring meristem.

<i>In Vitro</i>Organogenesis of <i>Quisqualis indica </i>Linn.

Shoot organogenesis and plant regeneration were achieved on callus derived from leaf section and stem base explants of Quisqualis indica (Combretaceae). In vitro cultures were established using nodal segments obtained from mature field-grown shrubby plants. For the development of optimized protocol, different types and concentrations of plant growth regulators were used to induce adventitious shoot regeneration via callus from leaf section and one-node stem base explants obtained from in vitro regenerated micro shoots and direct field-grown newly flush-off shoots. The TDZ was considered to be the best among the cytokinins (6-benzyladenine (BA), 6-(?-?, dimethylallyamino purine) (2-iP) and thidiazuron (TDZ) added to the Murashige and Skoog’s medium (MS) for adventitious shoot productions. A combination of 1.0 mg/L TDZ and 0.5 mg/L GA3 was most effective in stimulating callus induction and adventitious shoot regeneration from the leaf section derived calli with an average of 6 shoots per callus explant and an average of 8 shoots per callus explant originated from one-node stem base explants. In vitro raised shoots were sub-cultured on MS medium supplemented with 1.0 mg/L BA and 0.5 mg/L GA3 for further shoot growth. Maximum rooting of in vitro regenerated shoots was obtained on MS medium supplemented with either 0.5 mg/L indole-3-acetic acid (IAA) or indole-3-butyric acid (IBA) individually or a combination of 0.5 mg/L IAA and 0.5 mg/L IBA. Plantlets raised in vitro were acclimatized and subsequently transferred to experimental field.

Effect of Vitamins on <i>In Vitro</i>Organogenesis of Plant

Vitamins are necessary compounds synthesized and utilized in plants. In tissue culture media, vitamin addition is not always common;since the amount needed by plants is relatively unknown and varies. Vitamins, in combination with other media constituents, have been shown to have direct and indirect effects on callus growth, somatic growth, rooting, and embryonic development. For example, different studies have shown that thiamine is associated with cytokinin and has a role in inducing callus growth and rooting. Moreover, thiamine was essential in facilitating the production of more secondary metabolites such as proteases in pineapple. Both biotin and riboflavin play a role in callus development as well. Specifically, riboflavin exerts different effects on plant rooting either positively and negatively. Vitamin D known to cause uptake of calcium in animal tissue, exerts a similar effect in plants. In addition, vitamin D causes cell elongation and meristematic cell division. Vitamin C, known for its anti-oxidative properties, has also enhanced shoot growth and rooting.