scholarly journals Colchicine induction of ‘Old Blush’ 2n pollen for the hybridization and breeding of tetraploid rose

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11043
Author(s):  
Shumin Gao ◽  
Yahong Sun ◽  
Yan Zhou
Keyword(s):  
Treatment Time ◽  
Germination Rate ◽  
External Morphology ◽  
Tube Length ◽  
2N Pollen ◽  
Artificial Induction ◽  
Significant Difference ◽  
Important Means ◽  
Pollen Tube Length

Obtaining 2n pollen from the diploid Chinese old rose ‘Old Blush’ through artificial induction is one important means of hybridizing and breeding modern tetraploid roses. We used colchicine-induced 2n pollen to assess normal viability during hybridization and fructification. The results showed that the pollen mother cell had lagging chromosomes and parallel spindles at meiosis I stage, following which the 2n pollen was produced from dyads and triads with doubled chromosomes. We obtained 4.30% viable 2n pollen, which was significantly higher than the yield of the spontaneous 2n pollen (1.00%) using an optimal treatment combination of induction for 24 h with 0.50% colchicine. There was no significant difference between the external morphology of the induced 2n pollen and the spontaneous 2n pollen, whereas both types of 2n pollen possessed finer furrows, and fewer and smaller pores than the 1n pollen, and the external morphology of 2n pollen was more evolved. In terms of in vitro germination rate and pollen tube length, the induced 2n pollen did not differ significantly from the spontaneous 2n pollen. The survival rate of the floral buds was significantly decreased with increased colchicine concentration and treatment time.

scholarly journals Palynological investigations in Jasminum spp.

2020 ◽  
Vol 15 (2) ◽  
pp. 183-190
Author(s):  
M Ganga ◽  
J Lakshmi ◽  
N Manivannan ◽  
K Rajamani
Keyword(s):  
Pollen Germination ◽  
Tamil Nadu ◽  
Landscape Architecture ◽  
Germination Rate ◽  
Pollen Grain ◽  
Tube Length ◽  
Exine Ornamentation ◽  
Breeding Programmes ◽  
Pollen Tube Length

The present investigation was carried out at the Department of Floriculture and Landscape Architecture, Horticultural College and Research Institute, Tamil Nadu Agricultural University, Coimbatore during 2017-2019. The study involved nine jasmine genotypes, four falling under the commercially cultivated types and five belonging to underutilized species or ‘lesser-known species’. The study was undertaken to investigate and document the palynological parameters of jasmines which could serve as a reliable reference for future jasmine breeding programmes. The palynological investigations were carried out using Scanning Electron Microscopy (SEM), haemocytometry, acetocarmine test, and in vitro pollen germination. The pollen morphology analysis indicated wide variation among the species for the shape of the pollen grain, ranging from tricolpate to prolate; the exine ornamentation was reticulate in all the genotypes. Pollen output was the highest in J. rigidum (28,660 pollen/flower) and the lowest in (625 pollen/ flower) in J. sambac cv. Ramanathapuram Gundumalli. The maximum pollen germination rate and pollen tube length were recorded in J. rigidum.

scholarly journals GENETIC ANALYSIS OF THE TOMATO POLLEN BEHAVIOUR IN VITRO UNDER LOW TEMPERATURES

HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 584c-584
Author(s):  
P. J. Kaltsikes ◽  
P. J. Bebeli
Keyword(s):  
Pollen Tube ◽  
Pollen Germination ◽  
Genetic Model ◽  
Germination Rate ◽  
Tube Length ◽  
Gene Effects ◽  
Length Determination ◽  
Microscope Slides ◽  
Pollen Tube Length

The genetics of the ability of tomato pollen to germinate and grow in vitro under low temperature was investigated in two crosses namely “Resista” × “Hilda” and “Resista” × “Monita”. In each cross the following generations were utilised: F1, F2, BC1 and BC2, and their reciprocals, along with the parents. Pollen was placed on microscope slides having cavities filled with a liquid nutrient medium (water, 10% sucrose and 50 ppm boric acid) and allowed to germinate and grow for six hours at 15° C and then killed with acetocarmine. Germination rates and pollen tube length were determined and analyses on a genetic model allowing only for additive and dominance gene effects. For pollen germination rate both additive and dominance gene effects were significant while for tube length only the additive effects were. Dominance was towards lower rates of germination. At least three genes control pollen germination rates while seven or more are involved in pollen tube length determination.

Differences in Style Length and In vitro Germinated Pollen Tube Length and Other Reproductive Structures of Tetraploid and Diploid Cottons

2000 ◽  
Vol 3 (9) ◽  
pp. 1372-1374
Author(s):  
Mohammed Jurial Baloch . ◽  
Abdul Rahim Lakho . ◽  
Hidayatullah Bhutto . ◽  
Mohammad Hussain Arain .
Keyword(s):  
Pollen Tube ◽  
Tube Length ◽  
Style Length ◽  
Reproductive Structures ◽  
Germinated Pollen ◽  
Pollen Tube Length

Unilateral Cross-Incompatibility in Eucalyptus: the Case of Hybridisation Between E. globulus and E. nitens

1990 ◽  
Vol 38 (4) ◽  
pp. 383 ◽  
Author(s):  
PL Gore ◽  
BM Potts ◽  
PW Volker ◽  
J Megalos
Keyword(s):  
Pollen Tube ◽  
Pollen Tube Growth ◽  
Pollen Tubes ◽  
Full Length ◽  
Tube Length ◽  
Style Length ◽  
Similar Difference ◽  
Structural Barrier ◽  
Pollen Tube Length

The growth of E. globulus and E. nitens pollen tubes in styles of E. globulus was examined in order to elucidate the site of the unilateral barrier to hybridisation. Pollen tubes of E. nitens failed to grow the full length of the larger E. globulus style. E. globulus pollen tubes grew an average of 1.4 mm per day for the first 4 days, compared with 0.8 mm per day for pollen tubes of E. nitens. From days 4 to 14, the growth of E. nitens pollen tubes slowed to an average of 0.2 mm per day and virtually no growth occurred after day 14. In contrast, E. globulus pollen tubes grew through the style and into the ovary between days 5 and 14. By day 28, at about the time of style abscission, E. nitens tubes had grown only 6 mm, well short of the full length of the E. globulus style (9-10 mm). A similar difference in growth was obtained in vitro where E. nitens pollen tubes were significantly shorter than those of E. globulus. A comparison also including E. ovata, E. urnigera and E. gunnii indicated a significant correlation between style length and in vitro pollen tube length. It is argued that the unilateral cross-incompatibility between E. globulus and E. nitens is due to a structural barrier arising from an inherent limit to pollen tube growth which is associated with pistil size.

scholarly journals Influence of scarification method on seed germination of the terrestrial orchid Anacamptis laxiflora (Lam.)

2021 ◽  
Vol 5 (1) ◽  
pp. 15-23
Author(s):  
Gwenaëlle Deconninck ◽  
Argyrios Gerakis
Keyword(s):  
Infection Rate ◽  
Sucrose Solution ◽  
Germination Rate ◽  
Terrestrial Orchid ◽  
Significant Difference ◽  
Terrestrial Orchids ◽  
Sexual Propagation ◽  
Centrifugation Method ◽  
Bacteria And Fungi

AbstractA critical step during in vitro sexual propagation of terrestrial orchids is the treatment of the microscopic seeds with a disinfecting solution that kills bacteria and fungi attached to the seeds. This treatment is necessary to prevent infection of the culture vessels. At the same time, the treatment serves to scarify the seeds, a process that disrupts seed dormancy and initiates germination. The literature is inconclusive with respect to the proper combination of disinfecting solution strength and treatment duration. Both factors should be adapted to each species to guarantee minimal infection rate without damaging the embryo. This research aims to compare three disinfection/scarification methods for seeds of Anacamptis laxiflora (Lam.): (i) soaking in 0.5% NaClO, (ii) soaking in 0.5% NaClO, then centrifugation, and (iii) presoaking the seeds in sucrose solution, then soaking in 0.5% NaClO. The seeds were soaked in the disinfecting solution for 5 to 85 min. Following scarification, the seeds were sown in modified Malmgren nutrient medium. Infected and germinated vessels were counted at 41 and 189 d after sowing. We found that the longer the chemical treatment, the lower the infection rate, and the higher the germination rate. There was no significant difference in germination rate between the NaClO and the NaClO-plus-centrifugation method; in fact, the slight savings in disinfection time effected by centrifugation were more than offset by the added complexity of the method. Moreover, we found that centrifugation significantly delays germination. The sucrose presoak-plus-NaClO method was superior to plain NaClO, as the sucrose stimulates the germination of microbial spores on the surface of the seeds, making them easier to kill. Perhaps seeds with thicker testa as well as whole immature capsules could benefit even more from the pretreatment in sucrose solution.

scholarly journals Colchicine did not affect the viability of induced 2n pollen in Populus tomentosa

Silva Fennica ◽  
2019 ◽  
Vol 53 (2) ◽  
Author(s):  
Yan Liu ◽  
Yuan Zhang ◽  
Qing Zhou ◽  
Jian Wu ◽  
Pingdong Zhang
Keyword(s):  
Pollen Germination ◽  
Pollen Viability ◽  
Pollen Grains ◽  
Populus Tomentosa ◽  
2N Pollen ◽  
Significant Difference ◽  
Diploid Pollen ◽  
Germination Experiments ◽  
Diploid Gametes

Colchicine is widely used as a mutagen to induce production of diploid gametes in plants. However, whether colchicine affects induced pollen viability remains unclear. To clarify whether colchicine affected the viability of induced pollen, we induced production of diploid pollen by colchicine, followed by pollen germination and crossing induced pollen with normal gametes to produce triploid in Carrière. The results showed that the predominant meiotic stages and the number of colchicine injections had significant effects on the occurrence rates of induced 2n pollen. When the colchicine injection was given at diakinesis, a significant decrease in the pollen production per bud was observed ( < 0.001). The morphology of the colchicine-induced 2n pollen was similar to that of the natural 2n pollen in its ectexine structure. The pollen germination experiments revealed that there was also no significant difference in germination rates between the induced diploid pollen and natural 2n pollen grains, and 68 triploids were created by crossing colchicine-induced pollen. Our findings revealed that colchicine injection could induce to produce 2n pollen and will not lead to dysfunction of induced diploid pollen.in vitroPopulus tomentosapP. tomentosa

scholarly journals Fracture Resistance of a Bulk-Fill and a Conventional Composite and a Combination of Both for Coronal Restoration of Severely Damaged Primary Anterior Teeth

2019 ◽  
Author(s):  
Shahram Mosharrafian ◽  
Maryam Shafizadeh ◽  
Zeinab Sharifi
Keyword(s):  
Fracture Resistance ◽  
Treatment Time ◽  
Testing Machine ◽  
Anterior Teeth ◽  
Significant Difference ◽  
Group 3 ◽  
The Mean ◽  
Group 2 ◽  
One Way Anova

Objectives: This study aimed to compare the fracture resistance of a bulk-fill and a conventional composite and a combination of both for coronal restoration of severely damaged primary anterior teeth. Materials and Methods: In this in vitro experimental study, 45 primary anterior teeth were randomly divided into three groups. After root canal preparation, the canals were filled with Metapex paste such that after the application of 1 mm of light-cure liner, 3 mm of the coronal third of the canal remained empty for composite post fabrication. Filtek Z250 conventional composite was used in group 1, Sonic-Fill bulk-fill composite was used in group 2 and Sonic-Fill with one layer of Filtek Z250 as the veneering were used in group 3. Adper Single Bond 2 was used in all groups. The teeth were thermocycled, and fracture resistance was measured by a universal testing machine. The mode of fracture was categorized as repairable or irreparable. Data were analyzed using one-way ANOVA. Results: The mean fracture resistance was 307.00±74.72, 323.31±84.28 and 333.30±63.96 N in groups 1 to 3, respectively (P=0.55). The mean fracture strength was 14.53±2.98, 15.08±2.82 and 15.26±3.02 MPa in groups 1 to 3, respectively (P=0.77). The frequency of repairable mode of failure was 80% for the conventional, 73.6% for the bulk-fill and 80% for the bulk-fill plus conventional group, with no significant difference (P>0.05). Conclusions: Bulk-fill composites can be used for coronal reconstruction of severely damaged primary anterior teeth similar to conventional composites to decrease the treatment time in pediatric patients.

scholarly journals Effects of storage temperature and duration on pollen grain viability and pollen-tube elongation in Chinese chinqapin (Castanea henryi Skan)

2020 ◽  
Vol 49 (2) ◽  
pp. 297-304
Author(s):  
Huan Xiong ◽  
Deyi Yuan ◽  
Zhi-Yu Deng ◽  
Genhua Niu ◽  
Feng Zou
Keyword(s):  
Pollen Tube ◽  
Room Temperature ◽  
Storage Temperature ◽  
Southern China ◽  
Germination Rate ◽  
Pollen Viability ◽  
Pollen Grain ◽  
Tube Length ◽  
Storage Duration ◽  
Pollen Tube Length

Chinese chinquapin [Castanea henryi (Skan) Rehder & E.H. Wilson] is used as a food and timber crop in southern China. Most chinquapin cultivars are self-incompatible and bloom at different times; consequently, artificial pollination is used to ensure fruit set and nut yield. Effective pollen storage that enables producers and breeders to use stored pollen for cross-pollination at a later date is important. In this study, the cultivar Changmangzi was used to estimate the viability and pollen tube length of pollen stored at room temperature, and at 4, −20, and −80°C using in vitro germination tests. It was observed that pollen grain germination significantly decreased at all four storage temperatures. Pollen viability was 14.4% after only 24 days of storage at room temperature. The germination rate was 13.3% after 90 days of storage at 4°C, and 14.5% after 180 days at −20°C. The initial germination rate of pollen stored at −80°C was 56.3% at the beginning of the test and decreased to 15.4% after 240 days. Pollen-tube length decreased with increased storage duration; mean pollen-tube lengths ranged from 109.44 to 257.51 μm. Based on these results, it is suggested that a storage temperature of −80°C for Changmangzi pollen is good.

scholarly journals Effect of Galla Chinensis on Remineralization of Early Dentin Lesion

2020 ◽  
Vol 14 (04) ◽  
pp. 651-656
Author(s):  
Hend Mahmoud Abdel-Azem ◽  
Ahmed Fawzy Abo Elezz ◽  
Rehab Khalil Safy
Keyword(s):  
Treatment Time ◽  
Analysis Data ◽  
Environmental Scanning ◽  
X Ray ◽  
Parametric Data ◽  
Significant Difference ◽  
Ph Cycling ◽  
The Mean ◽  
Post Hoc

Abstract Objective This study aimed to investigate the efficacy of the Galla chinensis extract (GCE) on early dentin lesion remineralization. Materials and Methods Seventy-two dentin specimens were divided into three groups according to the treatment solution. In group S1, specimens were treated with GCE; in group S2, the specimens were treated with sodium fluoride (NaF); meanwhile, specimens of group S3 were treated with distilled water (DW). Each group was further subdivided into two subgroups according to the treatment time (1 minute and 5 minutes). An in vitro pH-cycling model for 12 days was done. Subsequently, surface microhardness (SMH) of the specimens, elemental analysis, and their micromorphological appearance were evaluated. Statistical Analysis Data were statistically analyzed. One-way analysis of variance was used to compare numerical (parametric) data between more than two separate groups followed by post hoc Tukey. Results There was no significant difference between the mean SMH of dentin between NaF and GCE groups. Regarding the time, the 5-minute treatment with NaF and DW groups recorded higher mean SMH value of dentin than the 1-minute treatment group. Meanwhile, for GCE groups, the 1-minute immersion recorded higher mean SMH value than the 5-minute immersion without any significant difference between them. The microhardness results were confirmed by environmental scanning electron microscope and energy dispersive X-ray analysis results. Conclusion GCE could be used as an effective alternative for dentin remineralization.

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