In Vitro Amphidiploid Induction of A Distant Hybrid Populus Simonii × P. Euphratica Cv. ‘Xiaohuyang-2’ and its Effect on Plant Morphology and Anatomy

In plants, highly gametic sterility of distant hybrids usually restricts their utilization in breeding programs. Amphidiploid induction produced by somatic chromosome doubling of distant hybrids can effectively restore their gametic fertility. In this study, nodal-segment and leaf explants of a distant hybrid Populus simonii × P. euphratica cv. ‘Xiaohuyang-2’ were used to induce chromosome doubling with colchicine in vitro. Although chromosome doubling of the nodal-segment explants only produced mixoploids, the treatments of leaf explants on adventitious bud regeneration medium successfully produced 4 amphidiploids, which might be attributed to the direct organogenesis of the adventitious buds on the leaf explants. The highest amphidiploid induction frequency was 16.7%. Both the explant survival rate and polyploidization frequency were significantly affected by colchicine concentration and exposure time. The amphidiploid plants were significantly differed from the diploid and mixoploid plants on morphological and anatomical characteristics. They had larger, thicker, and greener leaves than the diploids and mixoploids. The changes of stomatal features also accompanied with increase of ploidy level. The induced amphidiploid plants of the distant hybrid ‘Xiaohuyang-2’ are expected to play important roles in breeding programs of Populus in future, which can be used as a bridge parent with ability of unreduced gamete formation to cross with fast-growth germplasms to produce triploids pyramiding desirable traits of fast growth, easy cutting propagation, and salt and drought tolerances.

BA and TDZ in the Morphogenesis in Vitro of Passiflora Setacea

Passiflora setacea DC (Passifloraceae) is considered an important species in the genetic breeding of passion fruit. However, its use is limited due to low seed germination. This paper aimed to study the effect of cytokinins 6-benzyladenine (BA) and thidiazuron (TDZ) on the in vitro morphogenesis of P. setacea using three explants: hypocotyl, nodal segment, and root segment. The explants were induced to morphogenesis in MS medium modified and with different concentrations of BA and TDZ. After 55 days, the percentage of calluses and shoots were evaluated, and anatomical characterization was performed. The three explants used in the in vitro morphogenesis of P. setacea showed callus and shoots formation, but in greater numbers in the nodal segments treated with BA. TDZ isolated affected equal to or less than BA on callus and shoots formation for the three explants. Direct and indirect organogenesis was observed in the three types of explants. From the results obtained for plant regeneration via in vitro morphogenesis of P. setacea, it is recommended to use a nodal segment in MSM medium and supplemented with 2.22 μmol L-1 of BA.

Protocol Optimization for Rapid Multiplication of Cassava (Manihot esculenta Crantz) using the Nodal Segment

Background: Cassava is a vital food security crop for millions of people, especially in sub-Saharan Africa. Since the crop produces a reasonable yield on marginal soils, it could help alleviate world hunger. Consequently, the increase in cassava production and its quality characteristics are significant. However, the low multiplication rate of this main crop has delayed the spread of improved varieties among farmers. As a result, tissue culture techniques can be a viable solution to overcome these challenges. Methods: The study used a nodal segment as an explant to evaluate different concentrations of BAP and NAA for an efficient, cost-effective in vitro mass multiplication of the AWC-1 cassava variety. CuSO4, commercial bleach and ethanol had used to sterilize nodal explants taken from greenhouse-grown plants at various time intervals. Result: The best medium for micro shoots induction had found to be medium without growth regulators. Among different treatments used for shoot multiplication purposes, the maximum shoot number has been recorded on M.S. medium supplemented with 0.75 mg/l BAP and 0.2 mg/l NAA. Medium with 0.5 mg/l NAA concentration was the best for rooting induction. A survival rate of 86% has obtained in the greenhouse and the plantlets appeared to be morphologically normal.

In Vitro Propagation And Rejuvenation of Senescent Maternal Plant of Ardisia Crenata Var. Bicolor (Primulaceae)

Ardisia crenata var. bicolor is an ornamental shrub, owing to its declined wild population, recalcitrant seeds and few high-quality cuttings, the main objective of this study was to optimize an in vitro propagation protocol by using tip shoot and nodal segment as explants from senescent plant. Explants were sterilized and cultured on Muraghige and Skoog medium contained 1.0 mg·L-1 benzylaminopurine and 0.05 mg·L-1 1-naphthaleneacetic acid for shoot initiation. For shoot proliferation, explants were cultured on MS medium with 1.0 mg·L-1 BAP, 0.1 mg·L-1 NAA, and 0.5 mg·L-1 kinetin, and the proliferation coefficient were 3.1 and 2.5. Rooting was achieved by two explants in half-strength MS medium containing 0.5 mg·L-1 indole-3-butyric acid + 0.1 mg·L-1 or 0.2 mg·L-1 NAA, and 0.5 g·L-1 activated charcoal. The highest rooting rate were 72.7% and 65.1% with the highest mean number of roots (4.2 and 2.8, respectively). After acclimatization, 83.3% and 81.2% of plants were survived in the greenhouse. The plant can be rejuvenated via in vitro propagation and provide a reference for supplying the planting materials quickly with an uniform genotype.

An Alternate Cost-effective Medium for In Vitro Regeneration of Therapeutically Important Ocimum citriodorum Vis

ABSTRACT: A novel cost-effective in vitro regeneration protocol has been evolved for the therapeutically important Ocimum citriodorum Vis. In the present study, table sugar (3%) and isabgol (Psyllium husk) (3.5%) were used as an alternate source of carbon and gelling agent respectively in Murashige and Skoog’s (MS) medium. The explant used in the current study was nodal segment. A significant observation revealed that all the cultures resulted in shoot induction and maximum number of shoots/ culture (6.04) and their average length (2.15 cm) was obtained on modified MS-medium supplemented with table sugar, isabgol and BAP. However, best root induction (95.83%) was obtained on ½ MS-medium augmented with table sugar (3%) , isabgol (3.5%) and NAA. An increase in average number of roots per shoot (6.91%) as well as average root length (2.73 cm) was also observed in the same modified medium. The in vitro regenerated plantlets were successfully transferred to the field and no notable variation was observed in their morphology. The overall cost of culture medium for in vitro propagation of O. citriodorum Vis. was reduced significantly by 92.69% when agar and sucrose were replaced by isabgol and table sugar, respectively.

Development of In-Vitro Regeneration Protocol From Seedling Explants of Populus Gamblei Dode: A Difficult to Propagate Endemic Tree Species of Eastern Himalayas

This is the first report of in-vitro regeneration of Populus gamblei, an endemic and rare tree of montane to subtropical forest of Eastern Himalayas. Nodal segment from coppice shoot of young headed back seedling resulted in 100 % sprouting in MS + 1.0 mg L-1 BAP. Each micro shoot proliferated and gave 7.06 micro shoots on MS + 0.50 mg L-1 BAP + 0.10 mg L-1 IBA. In vitro multiplied shoots produced 100 % rooting in ½ MS + 0.5 mg L-1 NAA. In-vitro regenerated plants recorded 80 percent survival during hardening.

A Novel and Efficient In Vitro Organogenesis Approach for Ajuga lupulina Maxim

This work was aimed at establishing an effective approach for in vitro propagation of Ajuga lupulina Maxim, a medicinal and ornamental plant mainly found in eastern Xizang, in the western Sichuan region of China. We report an optimum response in the proliferation of axillary shoots from nodal segment explants (10.2 shoots/explant) on MS medium containing 3.0 mg L−1 of 6-benzyladenine (BA). When BA and TDZ individually or in combination with NAA were employed for adventitious shoot regeneration, shoots and embryo-like structures (ELSs) were noted in the callus from leaf explants. The maximum response of 26.4 shoots /explant (81.6%) and 12.0 ELSs/explant were ascertained on MS medium with 4.0 mg L−1 TDZ and 0.1 mg L−1 NAA. The leaf despite browning still demonstrated a high regeneration capacity. TDZ (2.0 mg L−1) and BA (2.0 mg L−1) along with NAA (0.01 mg L−1) were found to perform well for shoot regeneration via callus from shoot tip explants. The best for rooting was MS medium (half-strength) containing indole-3-butyric acid (IBA: 1.5 mg L−1) and (NAA: 0.5 mg L−1) with the maximum number of roots (25.8 per shoot) and the highest rooting frequency (81.71%). The survival of the plantlets in the greenhouse was 78.2% indicative of successful acclimatization. This work is the first report of a consistent, definitive, and unique protocol for A. lupulina regeneration, paving the way for the in vitro preservation of such significant genetic resources and also further allied systems based on such callus-based or embryo-based approaches.

Micropropagation of Rose (Rosa Hybrida) Using Invitro Technique by Natural Hormone

In recent years ,several Micropropagation technique has been established, to make some improved method of crop yield production the natural hormone from other plant species were selected for the beneficial result in the plant species. The Micro propagation technique is carried out in Rosa hybrida explant by providing the different natural shooting and rooting hormone in three different compositions with the half strength of MS medium , it is to predict the ability of which natural hormone is being utilized by the nodal explant of Rosa hybrida. The three different natural shooting and rooting hormone are Aloe vera gel extract and the tender coconut water with 50 ml and 100 ml and 150 ml of concentration in half strength MS media and the Cinnamon powder alone taken in the .5 g,1g and 1.5 g of concentration in half strength MS media due to the powdery form. These were proceeded in aseptic condition of propagation as a result it has been noticed that among the three natural hormone the remarkable growth has been found in the tender coconut water provided nodal segment in all the three concentration .This article has a goal to promote the use of the natural rooting role in the plant breeding industry.

Auxins and Cytokinins Involved in Micropropagation of Pepino Plant (Solanum muricatumAiton)

A reliable and successful micropropagation protocol was developed for pepino plant (Solanum muricatum Aiton) from nodal segment explants grown on MS medium. The best values of shoot multiplication traits were recorded from the addition of 3 mg.l-1 kinetin by producing 2.3 shoots/explant, 3.6 cm and 9.6 leaves/ explant which was significantly superior upon the addition of BA at the same levels. In case of adding 3 mg.l-1 kinetin, the best root formation attributes were achieved from the use of 0.2 mg.l-l IAA that resulted a maximum number of roots (14.33 roots/ explant). The longest root length (15.33 cm) was achieved when 0.3 mg.l-l IAA was used. A 100% rooting percentage was recorded from the all tested auxins including IAA, IBA and NAA. The gradually moved plantlets from the heterotrophic phase in the lab to the autotrophic phase in the greenhouse showed 100% success. The plantlets did not show any abnormal growth or morphological changes. It is concluded that this important plant can be easily propagated by tissue culture technique through a reliable micropropagation protocol.

Assessment of Genetic Stability of Micropropagated Bambusa balcooa Roxb. using RAPD Marker

Bambusa balcooa Roxb. was in vitro propagated by optimizing protocol using nodal segment from secondary branches with 100% success in MS liquid media containing 100 mg/l Myo-inositol, 3% sucrose supplement with 4.4 - 26.64 μM BAP for shoot multiplication, and 2.69 - 32.26 μM NAA for root induction. The highest shoot multiplication (14.53 ± 0.33 folds), shoot length (5.9 ± 0.6 cm), shoot number per explants (4.0 ± 0.24), and rooting (89.3 ± 0.33%) was obtained in MS liquid media supplement with 13.32 μM BAP (shooting) and 26.88 μM NAA (rooting) and 1% aqueous leaf extract of Artemisia vulgaris L. (EAV). Twenty RAPD (Random amplified Polymorphic DNA) primers were used individually to amplify DNA of tissue culture-raised plants and the mother plant where 8 primers yielded monomorphic banding patterns with reproducible, clear, scorable bands (2.8 per primer) ranging from 250 to 1800 bp respectively which revealed the micropropagated plants of B. balcooa retained their genetic stability. Plant Tissue Cult. & Biotech. 31(1): 81-95, 2021 (June)