Influence Of Plant Growth Regulators Research Articles

Influence of Plant Growth Regulators on In Vitro Morphogenesis in Sprout Culture of Potato (Solanum tuberosum L.)

Influence of Plant Growth Regulators on In Vitro Morphogenesis in Sprout Culture of Potato (Solanum tuberosum L.)

Influence of Plant Growth Regulators and Dark Pretreatment on Shoot Proliferation, Rooting and Acclimatization of Thorny Blackberry

Influence of Plant Growth Regulators and Dark Pretreatment on Shoot Proliferation, Rooting and Acclimatization of Thorny Blackberry

The Influence of Plant Growth Regulators on Callus Induction in Mature Rice Embryos (Oryza Sativa L) Amber Variety

Several nations across the globe depend profoundly on rice as the main food source. Several research works have been undertaken to improve rice yield and breeding, specifically concerning plant tissue culture. This paper aims to contrast the impact of several growth regulator levels on rice callus induction based on mature embryo explants. Over a four-week duration, mature rice plant embryos (Amber variant) were planted to produce calluses using the Skoog (MS) and Murashige supplements at different concentration levels, i.e., 2.0, 2.5, and 3.0 mg/L of 2,4-D and 0.2 and 0.3 mg/L of BA. The outcomes indicated that 3 mg/L 2,4-D and 0.2 mg/L BA levels led to optimal induction and fresh weight concerning callus. Further studies are required to enhance the media environment for potent in vitro callus induction to augment biotechnology endeavours.

Effect of different plant growth regulators on callus and adventitious shoots induction, polysaccharides accumulation and antioxidant activity of Rhodiola dumulosa

ObjectiveAs a medicinal plant, the resource of Rhodiola dumulosa is deficient along with the large collection. For the protection and utilization of R. dumulosa, the influence of plant growth regulators (PGRs) on callus induction and adventitious shoots differentiation, polysaccharide production and the antioxidant activity were tested. MethodsInternodes of R. dumulosa were used as explants and cultured on MS mediumplus different plant growth regulators (PGRs). The anti-oxidative activities of polysaccharides were evaluated using radical scavenging assays. ResultsBy response surface plot, 0.85 mg/L N6-benzyladenine (BA), 0.34 mg/L naphthaleneacetic acid (NAA) and 0.33 mg/L 2,4-dicholorophenoxyacetic acid (2,4-D) were the optimal factors for callus induction (90.03%) from internodes explants on MS medium. The fresh weight of green callus increased 47.26 fold, when callus was inoculated on MS + thidiazuron (TDZ) 0.5 mg/L + NAA 2.0 mg/L. Adventitious buds regenerated from callus on the media of MS were fortified with BA 1.0 mg/L plus NAA 0.5 mg/L, and the induction rate was 40.00%. MS plus indole-3-butyric acid (IBA) 1.0 mg/L produced the highest rooting rate with 10 to 15 roots in a length of 2–3 cm per shoot. The content of total polysaccharides in callus developed on MS + TDZ 0.5 mg/L + NAA 2.0 mg/L and MS + BA 1.0 mg/L + NAA 0.5 mg/L was as high as 1.72%−2.15%. At the dose of 0.5 mg/mL polysaccharides extracted from different callus induced on MS + NAA 2.0 mg/L + TDZ 0.5 mg/L or MS + BA 1.0 mg/L + NAA 0.5 mg/L or MS + BA 0.5 mg/L + 2,4-D 0.5 mg/L, the ABTS radical eliminating percentages were 82.78%, 80.18% and 68.59%, respectively, much higher than that of wild plant. ConclusionA rapid micropropagation system for R. dumulosa has been developed. The combination of TDZ and NAA or BA and NAA can increase the yield of the total polysaccharides. The polysaccharides isolated from callus and whole wild plants had stronger free radicals scavenging activities, indicating that polysaccharides from R. dumulosa are the potential pharmaceutical supplements.

Influence of plant growth regulators on in vitro biomass production and biosynthesis of cytotoxic Amaryllidaceae alkaloids in Caliphuria tenera Baker

Plants of the Amaryllidoideae subfamily are characterized by the presence of isoquinoline alkaloids called Amaryllidaceae alkaloids. These compounds have exhibited a broad spectrum of pharmacological effects, including anti-Alzheimer and anti-cancer. In this study, Caliphruria tenera Baker, Amaryllidaceae, an endangered and endemic species, was selected to evaluate the effect of growth regulators on plant micropropagation, biomass increase, and production of cytotoxic alkaloids. Different growth regulators were used individually and mixed, and the Amaryllidaceae alkaloids were identified and quantified by GC-MS. The maximum number of in vitro shoots (4.8) was recorded with 6-benzylaminopurine (BAP) (1 mg/L) + Kinetin (KIN) (1 mg/L) + Naphthaleneacetic acid (NAA) (0.2 mg/L). In addition, nineteen alkaloids were identified as crinine, galantamine, lycorine, narciclasine, and tazzetine-type alkaloids in cultivated and micropropagated plants. In general, the biomass was maximized with the growth hormone combination BAP + KIN + NAA, but the biosynthesis of alkaloids was minimized. However, the combination BAP + NAA showed the greatest productivity of trisphaeridine (632.01 μg/g). The growth regulators showed also a positive effect on the production of lycorine-type alkaloids with a content of 396.33 μg/g for KIN, 142.38 μg/g for BAP, and 41.67 μg/g for NAA. All alkaloid fractions were evaluated for their antiproliferative effects against human lung carcinoma (A549) and human keratinocytes (HaCat) cells. The alkaloids produced in the BAP + NAA treatment present a potent and selective cytotoxic against the A549 cell line at 30 μg/mL. This study shows that micropropagation is a promising approach for the production of cytotoxic Amaryllidaceae alkaloids in C. tenera without affecting natural populations.

Phytochemical Composition and Biological Activities of Extracts from Early, Mature, and Germinated Somatic Embryos of Cotyledon orbiculata L.

Cotyledon orbiculata L. (Crassulaceae)-round-leafed navelwort-is used worldwide as a potted ornamental plant, and it is also used in South African traditional medicine. The current work aims to assess the influence of plant growth regulators (PGR) on somatic embryogenesis (SE) in C. orbiculata; compare the metabolite profile in early, mature, and germinated somatic embryos (SoEs) by utilizing ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS); and determine the antioxidant and enzyme inhibitory potentials of SoEs. A maximum SoE induction rate of 97.2% and a mean number of SoEs per C. orbiculata leaf explant of 35.8 were achieved on Murashige and Skoog (MS) medium with 25 µM 2,4-Dichlorophenoxyacetic acid and 2.2 µM 1-phenyl-3-(1,2,3,-thiadiazol-5-yl)urea. The globular SoEs were found to mature and germinate best on MS medium with gibberellic acid (4 µM). The germinated SoE extract had the highest amounts of both total phenolics (32.90 mg gallic acid equivalent/g extract) and flavonoids (1.45 mg rutin equivalent/g extract). Phytochemical evaluation of SoE extracts by UHPLC-MS/MS reveals the presence of three new compounds in mature and germinated SoEs. Among the SoE extracts tested, germinated SoE extract exhibited the most potent antioxidant activity, followed by early and mature somatic embryos. The mature SoE extract showed the best acetylcholinesterase inhibitory activity. The SE protocol established for C. orbiculata can be used for the production of biologically active compounds, mass multiplication, and conservation of this important species.

Influence of plant growth regulators on growth and formation of sylleptic shoots in one-year-old apple cv. Gala Mast

Aim: To examine the effectiveness of 6-benzyladenine (BA) alone or in combination with gibberellic acid (GA3) on sylleptic shoots formation on one-year-old apple cv. Gala Mast grafted on MM-106 rootstock. Methodology: During the second vegetative period, the actively growing apical portion of the nursery tree was sprayed with varying doses of BA and BA+GA3 (200, 300, 400, 500, 600, and 700 ppm) using a hand sprayer until run-off. Three spray treatments were performed at one week apart. The first spray was applied when the growth of the central leader reached 70-80 cm. Results: All plant growth regulators treatments significantly increased the number and length of sylleptic shoots, branching zone and per cent branched trees compared to control. The unsprayed trees had an average of 1.95 useful sylleptic per tree, 1.1 m total sylleptic shoot length, 10.24 cm branching zone and 35 per cent branched trees. Application of BA (700 ppm) resulted in four-fold increase in the number of sylleptic shoots (7.8), more than two-fold increase in total length of sylleptic shoots (2.44 m), and around four-fold increase in branching zone (38.96 cm). The 100 per cent branched trees were obtained with the application of BA (500, 600, 700 ppm) and BA+GA3 (600, 700 ppm) in both experimental years. Moreover, these treatments obtained 2.78 to 2.90 values of the trunk and mean sylleptic shoot diameter ratio. Interpretation: Application of BA alone or in combination with GA3 played an important role in overcoming apical dominance and therefore in the production of well-branched apple nursery tree. However, application of BA alone has a stronger positive effect on sylleptic shoot formation. More than 400 ppm BA appears to give a significant stimulation for the production of sylleptic shoots, with the highest beneficial effect reported with the application of 700 ppm BA. However, it is cost-effective to apply 3 sprays of 500 ppm BA for adequate growth and sylleptic shoot production. Key words: 6-benzyladenine, Gibberellic acid, Nursery tree, Plant growth regulators, Sylleptic shoot

Secondary somatic embryogenesis in Cork oak: influence of plant growth regulators

Cork oak (Quercus suber L.) is one of the most important Mediterranean forest tree species, and the Maâmora forest-Morocco is considered to be the world largest cork oak stand. Clonal propagation of Quercus suber via somatic embryogenesis is an alternative to conventional tree propagation methods. However, complete maturation of somatic embryos is considered the major bottleneck for mass propagation of Quercus suber during somatic embryogenesis. This study focuses on influences of cytokinins on secondary somatic embryogenesis. Cytokinins showed a negative effect on the induction of secondary somatic embryogenesis. For the various concentrations tested, the number of secondary somatic embryos was significantly reduced except in the case with low dose of 2iP, which showed a slight increase. Abscisic acid (ABA) may be beneficial at low concentrations between 0.3 and 0.5 mg/l. The best number of secondary embryos was given at 0.5 mg/l ABA with an average number of 5 embryos from each primary embryo, which represents a slight increase below 10% compared to control medium. Also, we found that the number of responsive embryos presenting secondary somatic embryos based on their cotyledons decreased once adding ABA. Phenylurea derivatives TDZ and DPU do not promoted the process of secondary somatic embryogenesis. DPU showed no significant effect with a similar response to that of the control medium and TDZ showed an inhibitory effect. Gibberellic acid (GA3) partially blocked the process of somatic embryos multiplication, but promoted remarkably the germination of cotyledonary embryos without requesting a particular protocol. Our results provide a new insight into embryo development, establishing the basis for further research toward improvement of secondary somatic embryogenesis in Moroccan cork oak.

Content of chlorophyll and photosynthetic activity of sunflower under the influence of plant growth regulators in sunflower crops

Content of chlorophyll and photosynthetic activity of sunflower under the influence of plant growth regulators in sunflower crops

Influence of plant growth regulators on macro propagation in different banana genotypes

In vivo macro-propagation of banana has gained its momentum as an alternative source for mass multiplication of quality planting materials following some principles like decapitation, decortication of apical meristem of corm and hardening. 6- Benzylamino purine (BAP) @ 40ppm and 60ppm and Indole-3-butyric acid (IBA) @1000 ppm and 2000 ppm were used for locally grown banana genotypes viz. Bharatmani, Chini champa and Bhootmanohar to assess the response of plant growth regulators on shoot and root proliferation. The diseases free uniform corm and sterilized sawdust as uniform rooting media were used in experiment under polyhouse condition. The apical meristem of corm was scooped out with sterilized knife to make a cavity. The growth regulators BAP and IBA) were injected into the cavity of apical meristem 2 days after planting. Proliferation of primary (3.33 and 3.67) and secondary (4.0 and 4.33) buds were noticed significantly by Bharatmani and Chini champa treated with BAP @ 40 ppm and also took less time for bud proliferation.The genotype Chini Champa treated with BAP @ 40 ppm generated maximum number of plantlets per corm (14.67) while the highest number of explants (13.66) per corm after detaching was obtained by Bharatmani using BAP @ 40 ppm.

Influence of Some Plant Growth Regulators on Quality Attributes of Pineapple (Ananas comosus L.)

Aims: A trial was conducted to investigate the influence of plant growth regulators on the growth and quality attributes of pineapple fruits.
 Study Design: The experiment was arranged in a randomized completed block design (RBCD) with three replications using 25 plants per replication.
 Place and Duration of Study: The experiment was carried out between 2020 and 2021 at the Central Horticultural Experiment Station, Aignia, Bhubaneswar, India.
 Methodology: The application of PGRs i.e. naphthalene acetic acid (NAA), gibberellic acid (GA), and brassinosteroid (BR) was done at the flower initiation stage. Only water application is done in case of control. Fruits were harvested at the ripe stage and an analysis of different growth and quality parameters were done.
 Results: The application of naphthalene acetic acid (NAA), and gibberellic acid (GA) significantly improved the yield and quality attributes of pineapple. Application of NAA 200 mgL-1 (T3) was found to be the most effective in enhancing absolute growth rate (2.65 g day-1), fruit weight (1.58 kg), and fruit/crown ratio (6.38). It was also evident that the application of NAA 200 mgL-1 improved fruit quality in terms of soluble solid contents (17.67 oBrix), soluble solid contents to acid ratio (19.49), reducing sugar (3.54%), and total sugar content (12.38%). Higher pulp content (73.89%), pulp-to-peel ratio (3.49), and juice content (54.50%) were also observed with NAA 200 mgL-1.
 Conclusion: NAA 200 mgL-1 significantly improved fruit growth i.e. fruit weight, fruit-to-crown ratio, and absolute growth rate. It also enhanced the quality attributes of pineapple fruits i.e. pulp content, pulp-to-peel ratio, juice content, pH, soluble solid contents, SSC to acid ratio, reducing sugar, and total sugar content.

CONTENT AND RATIO OF PHOTOSYNTHETIC PIGMENTS IN STIPULES OF WINTER PEA WITH USING DIFFERENT GROWING TECHNOLOGIES

The article describes the results of research on the content and ratio of photosynthetic pigments in the stipules of winter peas using different cultivation technologies. The objects of the study were winter pea plants (Pisum sativum L.) of variety NS Moroz, plant growth regulator (PGR) Endofit L1 RK, bacterial preparation Bioinoculant BTU-r, microfertilizers «LF-Bobovi» and Biobor 140. The purpose of our research was to study the formation of photosynthetic pigments of winter pea plants under the action of growth regulator Endophyte L1 RK, bacterial preparation Bioinoculant BTU-r, their complex applying and foliar treatment systems with microfertilizers «LF- Bobovi» and Biobor 140. Analysis of chlorophyll and carotenoid content in alcohol extract (96.0%) was performed using a spectrophotometer Ulab − 102UV (China) at different values of wavelength: λ = 441; λ = 649; λ = 665. The volume of the working solution was 25 ml. Calculations of these indexes were performed according to the formulas of H. K. Lichtenthaler. During the study period, the influence of plant growth regulator, bacterial preparation, and foliar fertilization on the content of chlorophyll a and b, their sum, and concentration of carotenoids in the stipules of winter pea plants were evaluated. The research results indicate the dependence of these indicators on the use of the growth regulator and the bacterial drug, as well as on foliar fertilization. It was found that the implementation of foliar treatment in the phase of 3-5 stipules and complex use (in phases 3-5 of stipules and buttons) phase with tank mixtures of micro fertilizers «LF- Bobovi» (1.5 l / ha and 2.5 l / ha) and Biobor 140 (1.0 l / ha) led to an increase of the content of chlorophyll a and b, their total amount and carotenoid content. The highest content of chlorophylls a and b, their sum, and carotenoids in the stipules of winter pea plants were in the variant with the combined use of pre-sowing seed treatment with growth regulator Endophyte L1 RK (0.01 l / t), bacterial preparation Bioinoculant BTU-r (2 l / t) and at foliar treatment with microfertilizers «LF- Bobovi» (1.5 l / ha and 2.5 l / ha) and Biobor 140 (1.0 l / ha).The search for ways and opportunities to increase the grain yield of winter pea varieties Moroz due to the introduction of new technological methods of its cultivation remains relevant. A possible solution to the problem of improving the productivity of winter peas is the use of different mechanisms of action of plant growth regulators, inoculation with symbiotic microorganisms, and foliar feeding with tank mixtures of chelated microfertilizers.

Influence of Plant Growth Regulators and Artificial Light on the Growth and Accumulation of Inulin of Dedifferentiated Chicory (Cichorium intybus L.) Callus Cells.

Chicory (Chicorium intybus L.) is a perennial herb of the family Asteraceae, widely distributed in Asia and Europe, commonly used industrially as a raw material for extracting inulin because of a high content of inulin and biologically active compounds. Light conditions and plant growth regulators (PGRs) are two of many factors that affect the growth and inulin content of chicory callus. The aim of this work is to study the effect of PGRs and light conditions on proliferation and accumulation of inulin of chicory callus in vitro. In this study, we used semi-solid MS medium supplemented with different auxins (including Indole-3-acetic acid (IAA), naphthylacetic acid (NAA), and 2,4-dichlorophenoxyacetic acid (2,4-D)) at a concentration of 5.5–9.5 mg/L in combination with 2.0 mg/L 6 benzylaminopurine (BA) to determine induction and proliferation of callus. The increasing value of callus fresh weight was used to assess the growth of the callus in treatments. The results showed that a steady increase in callus fresh weight and inulin content in callus cells was obtained when they were cultured on MS medium supplemented with a combination of 2.0 mg/L BA with 7.5 mg/L IAA in lighting conditions with radiation equalized by the flux density of photosynthetic photons and ratios of radiation levels in the region of FR—far red > R—red. Increasing demand for organic inulin sources in production practice can be met by our finding.

Influence of Plant Growth Regulators on Glandular Trichome Density and Steviol Glycosides Accumulation in Stevia rebaudiana.

With the advent of modern lifestyles, diabetes-related comorbidities attributed the importance of low-caloric natural sweetener plants such as Stevia rebaudiana. This plant is the viable source of steviol glycosides (SGs) and other economically important secondary metabolites. Glandular trichomes (GTs) play the role as a reservoir for all secondary products present in the plant species. Therefore, the present study was carried out to evaluate the influence of different plant growth regulators (PGRs) on GT density and its impact on the SG content. The direct shoot regeneration system was developed on Murashige and Skoog (MS) + benzyl aminopurine (BAP) (1.0 mg/L) + naphthaleneacetic acid (NAA) (0.5 mg/L), and MS + BAP (1.5 mg/L) + NAA (0.5 mg/L) from nodal and leaf explants, respectively. Among the combination of PGRs used, MS medium fortified with BAP (1.0 mg/L) and 2,4-dichlorophenoxyacetic acid (2,4-D) (0.5 mg/L) played a significant role in increasing the GT density on leaf and stem tissues of S. rebaudiana. Furthermore, high-performance thin-layer chromatography and gas chromatography–mass spectrophotometry data confirmed a notable rise in SGs and other valuable secondary metabolites. Thus, the protocol developed can be used for the propagation of stevia with an improved metabolic profile at a large scale.

Effect of plant growth regulators on growth, yield and quality attributes of watermelon (Citrullus lanatus Thunb.)

Plant growth regulators are called as magic chemicals which are new generation agrochemicals. Exogenous application of plant growth regulators in small quantity can alter the sequence of male and female flowers, if applied at 2 or 4 leaf stages, the critical stage at which the suppression or promotion of either sex is possible. Therefore, a field experiment was carried out during Rabi, 2021 at Horticulture Research Farm, M.S. Swaminathan School of Agriculture, Centurion University of Technology and Management, Parlakhemundi, Odisha to study the influence of plant growth regulators on growth, yield and quality attributes of watermelon.Theexperiment was laid out under randomized block design with nine treatments namely 2, 4-D (25 and 50 ppm), NAA (100 and 150 ppm), GA3 (30 and 40 ppm), TIBA (20 and 25 ppm) and control (distilled water)replicated thrice. Two sprays of plant growth regulators were done at 2nd and 4th true leaf stages. The results revealed that, growth characters such as length of the main creeper (2.08 m), number of sub creepers per plant (4.40) and chlorophyll content (61.93 and 48.91 at 30 and 60 DAS) were highest in treatment (GA3 @ 40 ppm). The chlorophyll content at 90 DAS was highest (21.39) in treatment (NAA @ 100 ppm). The highest fruit yield plant-1 (17.51 kg) and fruit yield per hectare (44.17 t) was recorded in treatment (GA3 @ 40 ppm). The quality attributes such as Total Soluble Solid (TSS) (10.66%) and total sugars (15.03 %) were noted highest in treatment (GA3 @ 40 ppm). Among the different plant growth regulators spraying of GA3 @ 40 ppm found effective in enhancing the growth, yield and quality attributes of watermelon.

Influence of Plant Growth Regulators on Growth, Yield and Yield Components in Garden Pea

Background: Garden pea is one of the most important legume crop which require proper crop management practices. Crop regulation is an important practices which enhancing the productivity of garden pea with higher economic return. This can be done by adopting proper application of PGRs. Therefore, the present study was designed to assess the effect of PGRs on growth and yield of garden pea. Methods: The present study was laid out on garden pea (Pisum sativum subsp. hortense) cv. Azad Pea-3 in a randomized block design with three replications and ten treatments comprising different levels NAA, GA3 and Salicylic acid at various stages. The data on growth and yield were recorded and analyzed statistically applying the analysis of variance technique. Result: Results revealed that the plants treated with 120 ppm gibberellic acid showed 45.39% 38.55%, 40.60% and 32.84% increment in plant height, length of pod, width of pod and number of seeds per pod and taken lowest number of days to 50% flowering over control, respectively. The use of 40 ppm NAA exhibited maximal enhancement in number of pods per plant (57.43-68.02%), seed weight per pod and Pod yield per hectare (50.62-60.26%) over remaining treatments. Conclusively, the results suggest that foliar application of PGRs favors the growth and yield of garden pea.

Phyllanthus amarus shoot cultures as a source of biologically active lignans: the influence of selected plant growth regulators

This is the first comprehensive study of the influence of plant growth regulators (PGRs) on the development of shoots and accumulation of biologically active lignans—phyllanthin and hypophyllanthin, in the shoot culture of P. amarus Schum. & Thonn. (Euphorbiaceae) obtained by direct organogenesis. The following PGRs were included in the experiments—cytokinins: kinetin (Kin), 6-benzylaminopurine (BAP), 2-isopentenyladenine (2iP), 1-phenyl-3-(1,2,3-thiadiazol-5-yl)urea, thidiazuron (TDZ) and auxin, indole-3-butyric acid (IBA) and used at various concentrations. Depending on PGRs and their concentrations, differences in the culture response and lignan accumulation were observed. The highest content of the investigated compounds was found in the shoot culture grown on Murashige and Skoog’s (MS) medium supplemented with Kin 0.25 mg/L. The sum of phyllanthin and hypophyllanthin was ~ 10 mg/g of dry weight (DW), which was similar or even higher than that in the plant material obtained from natural conditions. The results of the research provide new data on the selection of the optimal growth medium for the production of plant material with a significant level of phyllanthin and hypophyllanthin biosynthesis. The obtained data may also be valuable in designing systems for large-scale cultivation of P. amarus shoots with high productivity of hepatoprotective lignans.

Influence of plant growth regulators on growth, flowering and fruit yield of bottle gourd [Lagenaria siceraria (Mol.) Standl.

The present investigation was carried out with three levelseach of five plant growth regulators namely, (IAA, TIBA,IBA, GA3 and Ethrel) respectively, were sprayed at secondand fourth leaves stage on bottle gourd plants to find outtheir response on growth, flowering and fruit yield. Thestudy was conducted at Vegetable Research Farm, CCS,Haryana Agricultural University, Hisar during Springsummerseason of 2017-18. The results clearly indicated thatapplication of Ethrel 200 ppm significantly increased mostof the growth and fruit yield attributes over control treatment.The spraying of Ethrel 200 ppm significantly reduced thelength of internodes (11.4 cm), days to appearance of firstmale flower and early fruit harvest (56.4; 62.7 days), numberof staminate flowers per plant (102.7), sex ratio (6.0) as wellas main vine length at final harvest (353.7 cm), whereas thesame dose significantly increases number of primarybranches /vine (16.8), numbers of pistillate flowers per plant(17.2), longer fruit length & more diameter (31.5; 7.3 cm),number of fruits per vine (7.6), average fruit weight (825.6 g)and fruit yield per plot and per hectare (27.6 kg and 349.2 q),respectively. Whereas, the spray of GA3 60 ppm significantlyreduced the number of primary branches per plant (9.9),number of pistillate flowers per plant (8.7), fruit length &diameter (22.9; 5.8 cm) number of fruit per plant (3.3) andfruit yield per plot and per hectare (18.7 kg, 238.4 q). Fromthe study, it was concluded that bottle gourd cv.GH-22 plantswhen sprayed with Ethrel 200 ppm produced the maximumfruit yield (349.2q/ha).

The Effects of Different Cytokinin Types and Their Concentration on in Vitro Growth of Apricot (Prunus armeniaca L.) Shoots

The objective of this study was to assess the effects of different cytokinin types [(6-benzylaminopurine (BAP), thidiazuron (TDZ) and meta-topolin (mT)] and their concentration on in vitro growth of apricot shoots. Sufficiently developed shoots were transferred to different multiplication media, which differed regarding the presence of cytokinin and its concentration. The subcultivation period lasted nine weeks. Analysis of covariance (ANCOVA) was performed to investigate the influence of plant growth regulators and their concentration on the final shoot weight of obtained tissue per regenerating explant. The results showed that all three cytokinins had a positive effect on shoot growth. There was a significant difference between used concentrations in the case of TDZ and BAP, while in the case of mT, the concentration did not significantly affect shoots’ regeneration. In our study, the most significant increase in shoots weight was obtained on medium supplemented with 1.0 mg/L BAP.

Differential Gene Expression and Withanolides Biosynthesis During in vitro and ex vitro Growth of Withania somnifera (L.) Dunal.

Ashwagandha (Withania somnifera L. Dunal) is a medicinally important plant with withanolides as its major bioactive compounds, abundant in the roots and leaves. We examined the influence of plant growth regulators (PGRs) on direct organogenesis, adventitious root development, withanolide biosynthetic pathway gene expression, withanolide contents, and metabolites during vegetative and reproductive growth phases under in vitro and ex vitro conditions. The highest shooting responses were observed with 6-benzylaminopurine (BAP) (2.0 mg L–1) + Kinetin (KIN) (1.5 mg L–1) supplementation. Furthermore, BAP (2.0 mg L–1) + KIN (1.5 mg L–1) + gibberellic acid (GA3) (0.5 mg L–1) exhibited better elongation responses with in vitro flowering. Half-strength MS medium with indole-3-butyric acid (IBA) (1.5 mg L–1) exhibited the highest rooting responses and IBA (1.0 mg L–1) with highest fruits, and overall biomass. Higher contents of withaferin A (WFA) [∼8.2 mg g–1 dry weight (DW)] were detected in the reproductive phase, whereas substantially lower WFA contents (∼1.10 mg g–1 DW) were detected in the vegetative phase. Cycloartenol synthase (CAS) (P = 0.0025), sterol methyltransferase (SMT) (P = 0.0059), and 1-deoxy-D-xylulose-5-phosphate reductase (DXR) (P = 0.0375) genes resulted in a significant fold change in expression during the reproductive phase. The liquid chromatography-mass spectrometry (LC-MS) analysis revealed metabolites that were common (177) and distinct in reproductive (218) and vegetative (167) phases. Adventitious roots cultured using varying concentrations of indole-3-acetic acid (IAA) (0.5 mg L–1) + IBA (1.0 mg L–1) + GA3 (0.2 mg L–1) exhibited the highest biomass, and IAA (0.5 mg L–1) + IBA (1.0 mg L–1) exhibited the highest withanolides content. Overall, our findings demonstrate the peculiarity of withanolide biosynthesis during distinct growth phases, which is relevant for the large-scale production of withanolides.