rLep Research Articles

Varietal diversity and selection of potential varieties of Petunia hybrida L. for commercial cultivation in Bangladesh

A study was conducted to compare the morpho-reproductive traits of twenty two genotype of Petunia in order to select superior and sustainable genotypes for commercial cultivation in Bangladesh during winter 2021-22. Thirteen qualitative and quantitative characters viz. stigma type, leaf shape, plant height (cm), number of branches, number of effective branches, days to flower initiation, number of flowers, duration of flowers, flowering duration, plant longevity, number of stamens, stamen length (cm) and petiole length (cm) were observed during the study period. The findings found that all morpho-reproductive traits differed significantly amongst the genotypes investigated, with the exception of the stamens, which were five in number. Highest quantitative variation was observed in days to flower initiation and longevity of the plants. Glow picotee blue showed the superior plant height (29.33 cm). Deep salmon had the shortest time to bloom initiation (52 days). Maximum number of flowers was recorded from ultra purple star (50) followed by ultra crimson star (49.67) while the duration of the flowers was maximum (6.67 days) in opera supreme white, prism pink, ultra burgundy star and ultra purple star. Opera supreme white had the longest flowering time (69.67 days). Whereas ultra purple star, ultra crimson star and ultra rose star had the longest lifespan (111 days). The genotypes deep salmon, ultra purple star, ultra red star, ultra rose star, opera supreme white, dreams midnight, and prism pink are recommended for commercial cultivation based on their overall morpho-reproductive performance. Jahangirnagar University J. Biol. Sci. 12(1 & 2): 23-33, 2023 (June & December)

Study of Genetic Variability among Some Petunia Hybrids at Chhattisgarh Plains

The present investigation entitled “Study of genetic variability among some petunia hybrids at Chhattisgarh plains” was carried out during the year 2022-23 at the Horticultural Research cum Instructional farm, College of Agriculture, Indira Gandhi Krishi Vishwavidyalaya Raipur (C.G.). The experiment was laid out in a Completely Randomized Design in three replications using 10 genotypes, viz., Daddy, Eagle, Dreams, Success 360, Mirage, Supercascade, Tritunia Crimson Star, Double Duo, Double Pirouette Rose and Double Glorious. The analysis of variance revealed significant differences for all the characters. The variability was studied among these different genotypes. The highest range as well as the highest GCV and PCV was found in the number of flowers per plant. The heritability ranged between 48.74 (plant spread at 90 days) to 99.97 per cent (number of leaves at 75 days). High heritability (>60%) was found in almost all characters. Genetic advance and genetic advance as per cent of mean were found to be maximum for number of leaves at 90 days (26.66) and leaf area (43.69) respectively. High heritability coupled with a high genetic gain was also observed in some characters indicating that these characters are most suitable for selective breeding.

In vitro Regeneration of Clematis Plants in the Nikita Botanical Garden via Somatic Embryogenesis and Organogenesis.

The effects of growth regulators, namely, 6-benzylaminopurine (BAP) and thidiazuron (TDZ), on the morphogenic capacity of 13 cultivars of clematis plants, in terms of their morphological structure formation, shoot regeneration, and somatic embryo development, are presented. The clematis cultivars ‘Alpinist,’ ‘Ay-Nor,’ ‘Bal Tsvetov,’ ‘Crimson Star,’ ‘Crystal Fountain,’ ‘Kosmicheskaya Melodiya,’ ‘Lesnaya Opera,’ ‘Madame Julia Correvon,’ ‘Nevesta,’ ‘Nikitsky Rosovyi,’ ‘Nikolay Rubtsov,’ ‘Serenada Kryma,’ and ‘Vechniy Zov’ were taken in collection plots of the Nikita Botanical Gardens for use in study. After explant sterilization with 70% ethanol (1 min), 0.3–0.4% Cl2 (15 min), and 1% thimerosal (10 min), 1-cm long segments with a single node were introduced to an in vitro culture. The explants were established on the basal MS medium supplemented with BAP (2.20–8.90 μM) and 0.049 μM NAA, or TDZ (3.0; 6.0, and 9.0 μM) with 30 g/L sucrose and 9 g/L agar. The medium with 0.89 μM BAP served as the control. Culture vessels and test tubes with the explants were maintained in plant growth chamber-controlled conditions: with a 16-h photoperiod, under cool-white light fluorescent lamps with a light intensity of 37.5 μmol m–2 s–1, at a temperature of 24 ± 1°C. Histological analysis demonstrated that adventitious bud and somatic embryo formation in studied clematis cultivars occurred at numerous areas of active meristematic cell zones. The main role of plant growth regulators and its concentrations were demonstrated. It was determined that maximum adventitious microshoot regeneration without any morphological abnormalities formed on the media supplemented with BAP or TDZ. 4.40 μM BAP, or 6.0 μM TDZ were optimal cytokinin concentrations for micropropagation. The explants of ‘Alpinist,’ ‘Ay-Nor,’ ‘Crimson Star,’ ‘Crystal Fountain,’ ‘Nevesta,’ and ‘Serenada Kryma’ cultivars displayed high morphogenetic capacity under in vitro culturing. During indirect somatic embryogenesis, light intensity 37.5 μmol m–2 s–1 stimulated a higher-number somatic embryo formation and a temperature of 26°C affected somatic embryo development. Active formation of primary and secondary somatic embryos was also demonstrated. 2.20 μM BAP with 0.09 μM IBA affected the high-number somatic embryo formation for eight cultivars. Secondary somatic embryogenesis by the same concentration of BAP was induced. The frequency of secondary somatic embryogenesis was higher in ‘Crystal Fountain’ (100%), ‘Crimson Star’ (100%), ‘Nevesta’ (97%), and ‘Ay-Nor’ (92%) cultivars. Based on these results, the methodology for direct somatic embryogenesis and organogenesis of studied clematis cultivars has been developed.

WILLIAM HERSCHEL AND THE 'GARNET' STARS: μ CEPHEI AND MORE

Although William Herschel's 'Garnet Star' (μ Cephei) is a prominent object, the story of the discovery of this famous red star is not well documented. Prior to and after Herschel, the identification of this star was the subject of confusion in various catalogues and atlases. The case is complex and involves other stars in southern Cepheus, including double stars, found by Herschel in the course of his star surveys. It is also fascinating to learn that μ Cephei is not the only star called "garnet" by him. This study reveals that there are 21 in all, resulting in a "Herschel Catalogue of Garnet Stars"—the first historical catalogue of red stars. Among them are prominent objects, which in the literature are credited to later observers. This misconception is corrected here, for Herschel was the true discoverer of all of them. The most interesting cases are Hind's 'Crimson Star', Secchi's 'La Superba', John Herschel's 'Ruby Star' and Schmidt's V Aquilae. Finally, we discussed whether Herschel speculated about the physical nature of his garnet stars, many of which are now known to be variable.

Preliminary Study of Sodium Chloride Tolerance of Rudbeckia fulgida var. speciosa ‘Goldsturm’, Heuchera americana ‘Dale's Variety’ and Aquilegia × cultorum ‘Crimson Star’ Grown in Greenhouse Conditions

Abstract Heuchera americana ‘Dale's Variety’, Aquilegia × cultorum ‘Crimson Star’ and Rudbeckia fulgida var. speciosa ‘Goldsturm’ were grown in a soilless medium and watered weekly with either 0.00 (control), 0.05, 0.15 or 0.25 M NaCl solutions for 6 weeks. Foliage and leachate were analyzed for pH, Na+ and Cl−, and digital images were taken of all plants. Sodium and chloride concentrations in the leachate increased over time, while pH values remained unchanged. Aquilegia and Rudbeckia took up both Na+ and Cl−in increasing amounts over time. Heuchera took up large quantities of Cl−initially, but lesser amounts over time, and minimal Na+ into the foliage until the last week. At the highest treatment levels of NaCl, all plants showed significant visual damage. Aquilegia was the first to show visual damage at 0.05 M NaCl. Heuchera was intermediate in terms of symptom development. Based on the results of this study, Rudbeckia and Heuchera are listed as salt tolerant, and Aquilegia is listed as salt intolerant.

Growth and Nutrient Response of Petunia and Marigold in Tire-containing Media

This study was conducted to determine the feasibility of using rock phosphate and acid pretreatment to reduce Zn availability in root media containing waste tire material for petunia and marigold production. Petunia × hybrida `Ultra Crimson Star' and Tagetes patula `Orange Boy' were grown in the greenhouse in media consisting of 4 perlite: 6 peat (v/v), 4 tire: 6 peat (v/v), or 4 tire (acid washed with 0.5 N HNO3): 6 peat (v/v); and containing various amounts of finely crushed rock phosphate ranging from 0 to 40 g. Bulk density was higher, while container capacity was lower in tire-containing media; air-filled porosity was comparable in both tire- and perlite-containing mixes. Total plant dry weight was highest in both crops grown in 4 perlite: 6 peat. Tissue concentrations of Zn were 2- to 3-fold higher in plants grown in media containing tire material. Tissue P was lower in petunia grown in tire media, but not in marigold. Compared to untreated tires, acid washing of tire components reduced tissue Zn levels in both crops, but had little effect on growth response. Visual analysis indicated that crop quality in tire media was unsatisfactory for petunia, but acceptable in marigold. Rock phosphate reduced leachate Zn levels in marigold, but not in petunia, and had no significant effect on growth and nutrition response in either crop. The data suggest that in addition to Zn, some other factor(s) may have limited growth of both species in tire-containing media.

MICRONUTRIENT TOXICITY IN PETUNIA HYBRIDA

Foliar micronutrient toxicity symptoms of Petunia hybrida `Ultra Crimson Star' were induced by elevated levels (from 0.25 to 6 mM) of boron (B), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo) and zinc (Zn) in the nutrient solution. Foliar toxicity symptoms of most micronutrients (except Fe) were characterized by leaf yellowing, interveinal chlorosis, and marginal necrosis. Mo toxicity was most severe. Leaf abnormality was not induced by Fe in the concentration range tested. Visible foliar toxicity symptoms developed when nutrient solution contained 5.4, 32, 28, 24, and 16 mg· liter-1, respectively, of B, Cu, Mn, Mo and Zn. Biomass yield was reduced when the fertilizer solution contained (in mg· liter-1): 22 B, 64 Cu, 335 Fe, 28 Mn, 24 Mo, and 33 Zn.

Induced micronutrient toxicity inPetunia hybrida∗

Abstract Plant micronutnent toxicity symptoms of petunia (Petunia hybrida) cv. Ultra Crimson Star were experimentally induced and characterized. Starting at the 3–4 true leaf stage, plants grown in peat‐lite mix in 11 cm pots were constantly fed for 5 weeks with fertilizer solutions containing 0.25, 0.5, 1, 2, 3, 4, 5, and 6 mM plus the control concentration of boron, copper, iron, manganese, molybdenum and zinc at pH 6.5. The control solution had 20 μM B, 0.5 μM Cu, 10 μM Fe, 10 μM Mn, 0.5 μM Mo, and 4 μM Zn. Foliar toxicity symptoms were produced when the nutrient solutions contained 0.5 mM (5.4 ppm) B, 0.5 mM (32 ppm) Cu, 0.5 mM (28 ppm) Mn, 0.25 mM (24 ppm) Mo, and 0.25 mM (16 ppm) Zn. Iron in the range of concentrations tested did not cause foliar toxicity. Reduction in dry matter yield was evident when 2 mM (22 ppm) B, 1 mM (64 ppm) Cu, 6 mM (335 ppm) Fe, 0.5 mM (28 ppm) Mn, 0.25 mM (24 ppm) Mo, and 0.5 mM (33 ppm) Zn were used in the fertilizer solution. Leaf chlorophyll contents decreased as Cu and Mn concentrations increased. Leaf chlorophyll contents increased as Fe in the fertilizer solution was elevated. The threshold tissue micronutrient levels that caused toxicity symptoms were also determined.

Micrometer observations of the Tempel3‐Swift periodic comet, with observations of three new double stars and four new nebulae. And on the crimson star BD+43°53

Micrometer observations of the Tempel₃‐Swift periodic comet, with observations of three new double stars and four new nebulae. And on the crimson star BD+43°53

Probably New Variable and Red Star

On May 22 I found, 2° 51′.7 north of Cygni, a deep red or crimson star, which is not in the Bonn Catalogue. The nearest to it there is + 47° 3167, which in declination corresponds with a white star that I observed at the same time, but not in R.A.