Self-pollination of the orchid Cycnoches haagii from Brazilian Cerrado results in albino phenotype seedlings

Abstract Cycnoches haagii Barb. Rodr. is an epiphytic orchid very targeted by collectors, but no reference was found in the literature about its reproductive biology. Thus, the purpose of this study was to obtain initial information regarding pollination types and its influence on seed viability of this native orchid of the Brazilian Cerrado, in order to enable future propagation and preservation programs. Pollination among flowers of the same plant (geitonogamy) or different plants (xenogamy) were carried out. Seeds extracted from the capsules were sown in B&G medium, with full and half strength. Seeds from geitonogamic resulted in 25% of albino protocorms and consequently in albino seedlings. This phenomenon did not occur in seedlings derived from xenogamic pollination. Pigment analysis showed that even the albino seedlings presented chlorophylls and carotenoids, however, in significantly minor concentrations, 16% and 37% respectively, in relation to green seedlings. Geitonogamic and xenogamic pollinations resulted in C. haagii viable seeds with high germination percentage (90%) under in vitro conditions. The germination of seeds from xenogamic pollination resulted in chlorophyll or normal seedlings only, and can be recommended at conservation programs. On the other hand, although geitonogamic pollination should be avoided at conservation programs of this orchid species as it leads to albino seedlings, it showed a very interesting system to obtain seedlings with this phenotype, an interesting plant material to future investigation.

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Methodology of the tetrazolium test for identifying viable seeds of orchids of the genus Cattleya native to the Brazilian Cerrado

Semina Ciências Agrárias ◽

10.5433/1679-0359.2021v42n3p1351 ◽

2021 ◽

Vol 42 (3) ◽

pp. 1351-1360

Author(s):

Luan Marlon Ribeiro ◽

◽

José Carlos Sorgato ◽

Jackeline Schultz Soares ◽

Jéssica Celeste Mônico Ramos ◽

...

Keyword(s):

Room Temperature ◽

Germination Percentage ◽

Seed Banks ◽

Brazilian Cerrado ◽

Randomized Design ◽

Conditioning Temperature ◽

Completely Randomized Design ◽

Viable Seeds ◽

Tetrazolium Test

Orchids need measures for conservation of their species, among them the creation of seed banks. This study analyzes suitable methodologies to identify the viability of Cattleya seeds through the tetrazolium test. Seeds of Cattleya nobilior Rchb. and Cattleya walkeriana Gardn. were submitted to three preconditioning: no soaking (control); sucrose (10%); or distilled water. After 24 hours, they were submitted to tetrazolium solution with three types of conditioning: oven (40 °C); water bath (40 °C); or room temperature. Subsequently, the percentage of viable seeds (VS) was calculated and in vitro sowing was carried out. Germination percentage (G) was determined after 45 days. A completely randomized design was used for each species studied, with treatments arranged in a 3x3 factorial scheme (three preconditioning and three conditioning), with eight replicates of one tube each. The experiment was performed in duplicate. The highest viability values found in the tetrazolium test were close to those of germination (C. nobilior: VS = 88% e G = 97%; C. walkeriana: VS = 88% e G = 95%) for Cattleya species native to the Cerrado. The conditioning at ambient temperature had a greater effect on seed visualization for both species studied, suggesting that the tetrazolium test should be performed at this conditioning temperature.

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Phenotypic aberrations during micropropagation of Soymida febrifuga (Roxb.) Adr. Juss

Notulae Scientia Biologicae ◽

10.15835/nsb619202 ◽

2014 ◽

Vol 6 (1) ◽

pp. 99-104 ◽

Cited By ~ 4

Author(s):

Kishore Kumar CHIRUVELLA ◽

Arifullah MOHAMMED ◽

Rama Gopal GHANTA

Keyword(s):

Seed Viability ◽

Ms Medium ◽

Stem Cuttings ◽

Endemic Plant ◽

Seedling Mortality ◽

Root Regeneration ◽

Half Strength ◽

Shoot Necrosis

Like most of the medicinal plants Soymida febrifuga (Meliaceae) possess significance for its valuable secondary metabolites. Multiplication of this endemic plant is limited by difficulty in rooting of stem cuttings, high seedling mortality rates and low seed viability period. Hence efficient protocols for in vitro mass propagation has been established from field grown and aseptic seedlings explants. Strikingly, we observed aberrant structures such as vitrified shoots, faciated shoots, albino shoots as well shoot necrosis during its micropropagation. These phenotypic maladies were observed during organogenesis and rooting. Compared to other abnormalities, shoot necrosis nonetheless was frequent and pronounced leading to plant death. Shoots when subjected to rooting also displayed necrosis which was controlled by transferring to MS medium containing various concentrations and combinations of calcium levels, activated charcoal, glucose, fructose and auxins. Microshoots initiated roots on half strength MS medium with IBA and IAA individually or in combination within two weeks. MS half strength solid medium supplemented with CAN (556 mg l–1), CAP (1.0 mg l–1), IAA (2.0 mg l–1) and IBA (2.0 mg l–1) in combination was found to be more efficient in showing high frequency (95%) of root regeneration. Rooted plantlets were successfully hardened and 70-85% of regenerated plants were successfully acclimatized to natural environment. In vitro derived plantlets were morphologically similar to in vivo plants.

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In vitro Propagation of Laelia albida (Orchidaceae) for Conservation and Ornamental Purposes in Mexico

HortScience ◽

10.21273/hortsci.40.2.439 ◽

2005 ◽

Vol 40 (2) ◽

pp. 439-442 ◽

Cited By ~ 11

Author(s):

Leticia Santos-Hernández ◽

Martha Martínez-García ◽

Jorge E. Campos ◽

Ernesto Aguirre-León

Keyword(s):

Culture Media ◽

Potato Starch ◽

Seed Viability ◽

Germination Percentage ◽

Coconut Water ◽

Naphthaleneacetic Acid ◽

Monthly Basis ◽

In Vitro Techniques ◽

South Central

The orchid Laelia albida is an important cultural and religious plant resource of the Tehuacan-Cuicatlan Valley Biosphere Reserve in south-central Mexico. It is gradually becoming scarce due to overcollecting and habitat perturbation. For this reason, and for preservation purposes, the aim of the present work was to obtain the conditions to successfully propagate this species, through the use of mature seeds stored at 4 °C, and basal buds following in vitro techniques. Seeds with different storage periods (lot 1 and lot 2) were analyzed for seed viability as determined by the TTC method, germination percentage and germination index were analyzed on a monthly basis for 11 months on two Knudson C (K-4003, K-4128; Sigma). Seedlings were initially grown on the same culture media variants, but 30 days later they needed to be supplemented with potato starch (20 g·L-1). Basal buds were cultured on Knudson C containing nine BAP and NAA combinations two of which were also supplemented with potato starch (20 g·L-1) and coconut water (10%). Seed viability ranged from 78% to 98% throughout the 11 months and germination percentage was 70% to 90% without significant differences between the two lots. K-4003, either alone or supplemented with potato starch, was the best culture medium used to achieve all the development stages as well as seedlings with rhizoids. Bud proliferation was also successful on K-4003 added with BAP, NAA, potato starch and coconut water. The BAP (7.4 μm) and NAA (5.3 μm) combination promoted shoots and protocorm-like bodies (PLB). The results obtained with basal buds, make its preservation through in vitro culture possible and give the possibility to obtain available plantlets for its cultivation in regional nurseries. Storage conditions tested here may be useful for seed bank management for this species. Chemical names used: 6-benzylaminopurine (BAP), 1-naphthaleneacetic acid (NAA).

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The Effect of Sodium Hypochlorite (NaOCl) and Heat Treatments on Seed Germination of Rice: An Approach to Restore Seed Viability

Journal of Experimental Agriculture International ◽

10.9734/jeai/2021/v43i530689 ◽

2021 ◽

pp. 49-53

Author(s):

Monoj Sutradhar ◽

Subhasis Samanta ◽

Brijesh Kumar Singh ◽

Md. Nasim Ali ◽

Nirmal Mandal

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Sodium Hypochlorite ◽

Seed Viability ◽

Germination Percentage ◽

Heat Treated ◽

Mother Plants ◽

Breaking Seed Dormancy ◽

One Year

Dormancy in rice serves as a mechanism of survival by protecting the seed from germinating in the mother plants; however, it becomes a problem in germination during sowing in soil or under in vitro conditions. This study was conducted to determine the effect of heat treatment and sodium hypochlorite (NaOCl) treatment of seeds on dormancy alleviation. The seeds included both freshly harvested seeds and one-year-old stored seeds, which were tested for germination after different types of seed treatments. Both the treatments increased the germination percentage in seeds, however, it was lesser in the case of old seeds. The best results were obtained from 2% NaOCl treatment for 24 hrs in new seeds, i.e. 92.84±0.103 % germination percentage (GP). However, the higher GP in old seeds were obtained from 48 hrs of heat-treated seeds i.e. 82.9±0.509 % GP. The results of the experiment revealed that rice seeds start to lose viability within a year due to seed dormancy, but this can be reversed with proper measures. These methods of breaking seed dormancy can be considered effective to break seed dormancy and improve seed germination in rice.

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Phenology and seed germination of the Indian Screw Tree Helicteres isora L. (Malvales: Malvaceae)

Journal of Threatened Taxa ◽

10.11609/jott.3058.9.12.11040-11044 ◽

2017 ◽

Vol 9 (12) ◽

pp. 11040 ◽

Cited By ~ 2

Author(s):

Mariappan Muthukumar ◽

Thiruppathi Senthil Kumar ◽

Mandali Venkateswara Rao

Keyword(s):

Seed Viability ◽

Early Summer ◽

Seedling Development ◽

Ms Medium ◽

Seed Setting ◽

Flower Buds ◽

Helicteres Isora ◽

Half Strength ◽

Mature Seeds

Helicteres isora L. (Malvaceae), a medicinally important tree species used in Ayurveda as well as by folklore practitioners, is studied for its phenology, associated problems with the environment and anthropogenic effects. In Helicteres isora, flower buds are initiated by the end of July and flowering occurs during the middle of August to late October. Fruits mature during late January to early April. In between various factors like blister beetles, unidentified worms, deficit rainfall, early summer affect the flowering and seed setting, which cause 35–45 % loss. Seed viability of mature seeds were recorded 88.2% at fresh collection and decreases over period of time. In vitro, among the various treatments, acid treated seeds (H2SO4, 98.0%; 1 min) resulted in the best germination response of 84.5%. Sterile wet cotton soaked with sterile distilled water was found suitable for germination compared to other substratum, while half-strength MS medium with 2.0% sucrose was suitable for seedling development.

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Light sources on the germination and initial in vitro establishment of Schomburgkia crispa Lindl., a species of the Brazilian Cerrado

Ciência Rural ◽

10.1590/0103-8478cr20190022 ◽

2021 ◽

Vol 51 (3) ◽

Author(s):

José Carlos Sorgato ◽

Erick Dutra Mudolon ◽

Fernando Figueiredo Guimarães ◽

Jackeline Schultz Soares ◽

Luan Marlon Ribeiro

Keyword(s):

Germination Percentage ◽

In Vitro Cultivation ◽

Light Sources ◽

White Led ◽

Brazilian Cerrado ◽

Seedling Mortality ◽

Fluorescent Lamps ◽

Growth Room ◽

In Vitro Establishment

ABSTRACT: Light is one of the factors that influence the germination and initial establishment of orchids under in vitro cultivation. This study evaluated the effect of different light sources on these stages in in vitro cultivation of Schomburgkia crispa Lindl. After sowing in an aseptic environment, we stored the cultures in a screened greenhouse (natural light) or in a growth room with the following light sources: 3,000 K yellow LED; 6,500 K white LED [1]; 6,500 K white LED [2]; or 6,500 K white fluorescent lamp (control). We assessed germination percentage and initial seedling establishment at 45 and 90 days after sowing. Light did not influence the germination of S. crispa. However, the use of 3,000 K LED provided a faster initial establishment of S. crispa when compared to the other light sources, also presenting lower seedling mortality. Thus, the light source 3,000 K LED is a potential substitute for the 6,500 K fluorescent lamps and LEDs used in growth rooms in in vitro culture laboratories.

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Effect of moisture content on in vitro regeneration of embryonicaxis explants of cowpea Vigna unguiculata L.

Legume Research - An International Journal ◽

10.18805/lr.v0iof.3768 ◽

2016 ◽

Author(s):

Anju Jain ◽

Kalyani Srinivasan ◽

R. P. Yadav ◽

Aradhana Mishra

Keyword(s):

Vigna Unguiculata ◽

Culture Media ◽

In Vitro Regeneration ◽

Embryo Rescue ◽

Seed Viability ◽

Germination Percentage ◽

Embryonic Axis ◽

Moisture Contents ◽

Tissue Culture Media

To see the effect of ultra desiccation on seed survival, cowpea (Vigna unguiculata L.) seeds were conditioned to various moisture contents ranging from 8-2%. When monitored after one year of storage, variability was observed in seed viability in the seeds conditioned to different moistures. Seeds conditioned to very low moisture contents exhibited greater loss in viability. Therefore, efforts were made to see the possibility of germinating the embryo under artificial condition using various media and growth regulators. The effect of various combinations of hormone in plant tissue culture media were evaluated on the growth of excised embryonic axis in vitro to develop an embryo rescue protocol. An efficient protocol was developed for in vitro shoots regeneration from cowpea embryonic axis to improve the survival of low viability seeds to avoid the loss of potentially valuable genes. Shoots were developed in most of the explants on medium containing MS salts and B5 vitamins supplemented with 0.2 mg/l BAP. All the regenerated shoots were rooted on the same medium and in vitro plantlets were acclimatized in pots containing soilrite at room temperature. All the plants produced healthy seeds after 2 months in greenhouse. This protocol can be used to rescue cowpea germplasm with low germination percentage which results in successful regeneration

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Aspects of Peltophorum dubium Sprengel (Taubert) seeds in an aerial seed bank

Journal of Seed Science ◽

10.1590/2317-1545v39n1168605 ◽

2017 ◽

Vol 39 (1) ◽

pp. 32-40

Author(s):

Girlânio Holanda Silva ◽

Anderson Cleiton José ◽

José Marcio Rocha Faria ◽

Wilson Vicente Souza Pereira

Keyword(s):

Moisture Content ◽

Seed Bank ◽

Natural Regeneration ◽

Protein Profile ◽

Seed Viability ◽

Germination Percentage ◽

Abstract Knowledge ◽

High Germination ◽

Before And After ◽

Local Ecosystem

Abstract: Knowledge concerning natural regeneration strategies is important due to the effect of natural regeneration on the local ecosystem. The aim of this study was to examine the ecophysiological aspects of the Peltophorum dubium aerial seed bank. Fruits were harvested monthly, before and after seed maturation, from selected trees in the municipality of Lavras, MG, Brazil, for determination of moisture content, acquisition of tolerance to desiccation, seed viability, maintenance of dormancy, and mean germination time. Physiological maturity of the species was attained in June, when low moisture content, maximum dry matter, and high germination percentage were observed. We found that there was no change in dormancy, in germination percentage, or in the protein profile of seeds during the period they remained in the aerial seed bank. The P. dubium species creates an aerial seed bank of short serotiny, with fruits remaining attached to the tree for 9 months.

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Seed Cryostorage and Micropropagation of Georgia Aster, Symphyotrichum georgianum (Alexander) Nesom: A Threatened Species from the Southeastern United States

HortScience ◽

10.21273/hortsci.48.6.750 ◽

2013 ◽

Vol 48 (6) ◽

pp. 750-755

Author(s):

Sullivan Lynch ◽

Rachel K. Johnston ◽

Ron O. Determann ◽

Jennifer M. Cruse-Sanders ◽

Gerald S. Pullman

Keyword(s):

Room Temperature ◽

Natural Populations ◽

Seed Viability ◽

Shoot Multiplication ◽

Small Population ◽

Shoot Cultures ◽

Control Seed ◽

Population Sizes ◽

Half Strength

Symphyotrichum georgianum (Asteraceae), commonly known as Georgia aster, is a candidate for listing under the Federal Endangered Species Act in the four southeastern U.S. states where it lives. Rarity of this species is thought to be attributable in part to small population sizes and limited seed production. Protocols for in vitro germination, sustainable shoot micropropagation, shoot establishment in soil, and seed cryopreservation are presented that will assist in the safeguarding and augmentation of dwindling natural populations. Germination in vitro on growth regulator-free half-strength Murashige and Skoog (MS) medium after sterilization in H2O2 initiated the development of shoot cultures. Shoot multiplication and elongation occurred on half-strength MS salts containing 0.1 mg·L–l benzylaminopurine and 0.2 mg·L–l gibberellic acid, producing an average of 18 new shoots over a 6- to 8-week subculture cycle. Shoots rooted easily when planted into cutting mix after treatment with rooting powder containing indole-3-butyric acid (IBA) or in vitro rooting in medium with or without N-acetyl-L-aspartic acid (NAA). Plant survival after 1 month was 90% or higher for all treatments. Cryopreservation tests with seeds from three populations averaged 46.7% germination compared with control seed (no cryostorage) germination of 43%; differences were not statistically significant. Fresh seeds and seeds equilibrated for 1 to 4 weeks at room temperature and 12% relative humidity did not differ significantly in germination post-cryopreservation. Initial observations suggest that Georgia aster rapidly loses seed viability over 1 to 2 years when stored at room temperature. The ability to increase seed longevity through cryopreservation storage may be a critical step in the conservation of this species.

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Endozoochory by Goats of Two Invasive Weeds with Contrasted Propagule Traits

Sustainability ◽

10.3390/su12135450 ◽

2020 ◽

Vol 12 (13) ◽

pp. 5450

Author(s):

Ahmed M. Abbas ◽

Mohammed Al-Kahtani ◽

Mohamed Abdelazeem Mousa ◽

Mohammed O. Badry ◽

Ahmed S.A. Hassaneen ◽

...

Keyword(s):

Digestive System ◽

Control Method ◽

Seed Viability ◽

Plant Invasions ◽

Germination Percentage ◽

Invasive Weeds ◽

Seed Traits ◽

Physical Dormancy ◽

Socioeconomic Impacts ◽

Viable Seeds

Invasive plants have very important ecological and socioeconomic impacts. Producing and dispersing many viable seeds are key plant functional traits for invaders. Ungulate grazing plays an important role in the endozoochorous seed dispersal within grasslands and rangelands. Grazing can be applied as a practical and economical control method for plant invasions. We analyzed the effects of seed passage through the goat digestive system on the germination and viability for Sorghum halepense and Malva parviflora, common invasive species with contrasted propagules and seed traits. Both studied species produced seeds able to survive, in a small percentages (c. 0.80–1.70%), after being eaten by goats. Most of the seeds (c. 40–55%) of both species were retrieved between 24–48 h after ingestion. Goat passage provoked a decrease (> 60%) in the germination percentage and seed viability of S. halepense that was higher with longer gut retention times. In M. parviflora, the goat gut passage did not break its primary physical dormancy, since no retrieved seed germinated with similar viability as the uneaten seeds (c. 90%). In view of our results, goat grazing can be applied as a useful method to control S. halepense and M. parviflora invasions. Goats should be kept in corrals for at least 4 days after grazing to prevent transferring viable seeds to uninfected areas.

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