Influence of daylength and temperature during formation of seed potatoes on subsequent growth and yields under long day conditions

2002 ◽  
Vol 45 (2-4) ◽  
pp. 139-143 ◽  
Author(s):  
Tor J. Johansen ◽  
Leidulf Lund ◽  
Jarle Nilsen
Keyword(s):  
Subsequent Growth ◽  
Seed Potatoes ◽  
Long Day

Effect of Methods of Storage on Subsequent Growth and Yield of Seed Potatoes

1965 ◽  
Vol 8 (1) ◽  
pp. 0138-0140 ◽  
Author(s):  
L. W. Neubauer ◽  
B. J. Hoyle and E. Kucera
Keyword(s):  
Growth And Yield ◽  
Subsequent Growth ◽  
Seed Potatoes

scholarly journals Multiplication of seed potatoes by tuber formation in leaf axils of stems derived from single-bud stem cuttings.

1987 ◽  
Vol 35 (1) ◽  
pp. 29-36
Author(s):  
J. Marinus
Keyword(s):  
Soil Surface ◽  
Stem Growth ◽  
Tuber Formation ◽  
Stem Cuttings ◽  
Single Node ◽  
Seed Potatoes ◽  
Short Day ◽  
Long Day ◽  
Short Days

Single-node cuttings of 3 cultivars were planted in such a way that the buds were some centimetres above the soil surface. Some of the plants were grown under long-day conditions, the others under short days during stem growth, this being favourable to tuber formation in normal plants. Stems growing from the buds showed abundant tuber formation in the leaf axils of Jaerla (early) and Bintje (mid early), especially under short-day conditions, but fewer tubers were formed in Alpha (late). This cultivar formed many thickened branches instead of tubers under short-day conditions. Under long days Jaerla and Bintje formed many above-ground tubers, whereas half of the cuttings of Alpha did not form tubers. When planted, above-ground tubers produced good yields. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Effect of Irradiance Level and Paclobutrazol on Reducation of Leaf Damage in Begonia × cheimantha

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 446d-446
Author(s):  
Beyounghan Yoon ◽  
Harvey J. Lang
Keyword(s):  
Day Treatment ◽  
Leaf Damage ◽  
Growth Retardants ◽  
Damage Development ◽  
Long Day ◽  
Leaf Chlorosis ◽  
Shade Cloth ◽  
Growing Conditions ◽  
Reduced Light ◽  
Shade Plants

Begonia × cheimantha (Christmas or Lorraine begonia) is a popular holiday crop in Europe, with certain cultivars having outstanding postharvest characteristics. Its commercial production in the southern United States has been limited by the occurrence of mottled leaf chlorosis and necrosis, apparently due to environmental stress. In this study, B. × cheimantha `Emma' was grown in the fall in a glass greenhouse at College Station, Texas, under either 0%, 60%, or 87% polyethylene shade cloth. Leaf chlorosis and necrosis was very severe on plants grown in full sun (≈650 mol·m–2·s–1), with slight chlorosis on plants under 60% shade. Plants under full sun, however, were more compact, flowered earlier, and had shorter peduncles with more flowers than those grown under shade. Reducing the vegetative long-day treatment period from 7 to 4 weeks had no effect on leaf damage development. Plants treated with paclobutrazol were shorter and had less leaf damage than untreated plants. Leaves of treated plants had a relatively higher concentration of soluble protein, chlorophyll, and enhanced activities of ascorbate peroxidase (AsA), dehydroascorbate (DHA) reductase, and monodehydro-ascorbate (MDHA) reductase than untreated plants. For Texas growing conditions, these preliminary studies indicate that B. × cheimantha should be grown under reduced light intensities, with excessive height and leaf damage being controlled with growth retardants such as paclobutrazol.

Photoperiod and Temperature Influence on Flower Initiation and Development for Euphorbia pulcherrima Grown Under Florida Conditions

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 509a-509
Author(s):  
C.E. Wieland ◽  
J.E. Barrett ◽  
D.G. Clark ◽  
G. J. Wilfret
Keyword(s):  
Subsequent Development ◽  
Flower Initiation ◽  
Euphorbia Pulcherrima ◽  
Floral Initiation ◽  
Temperature Influence ◽  
Average Temperature ◽  
Long Day ◽  
Time To Initiation ◽  
Growth Room ◽  
Maximum Temperatures

Four poinsettia cultivars were grown in glass greenhouses in Gainesville, Fla., in the Fall 1997 to evaluate differences in floral initiation and subsequent development. Three means of regulating photoperiod were 1) natural days 2) long-day lighting to 6 Oct. and then natural days (lights out) 3) long-day lighting to 6 Oct., and then short-day conditions by black cloth for 15 h (black cloth). At 2-day intervals, sample meristems were collected and examined for initiation of reproductive development. Average minimum and maximum temperatures during the first two weeks of October were 22 and 29 °C, respectively, with an average temperature of 25.3 °C. The overall average temperature was 23.2 °C from planting to anthesis. Differences in anthesis dates among cultivars were primarily due to time to initiation vs. rate of development. Under natural days, `Lilo' initiated first on 8 Oct. and `Freedom', `Peterstar', and `Success', followed by 6, 8, and 18 days, respectively. Lights out resulted in `Lilo' initiating 17 Oct., followed by `Freedom', `Peterstar', and `Success' initiating 7, 12, and 15 days later, respectively. Differences between cultivars in time of initiation was reduced under black cloth, where `Lilo' initiated 14 Oct., followed by `Freedom' 2 days later, and `Peterstar' and `Success' 7 days afterward. Initiation was positively correlated to visible bud and anthesis. First color was positively correlated to initiation and visible bud, with the exception of `Lilo'. Growth room studies conducted using various high temperatures and photoperiods indicated similar trends.

scholarly journals When Authenticity Goes Missing: How Monocultural Children’s Literature Is Silencing the Voices and Contributing to Invisibility of Children from Minority Backgrounds

2021 ◽  
Vol 11 (1) ◽  
pp. 32
Author(s):  
Helen Adam
Keyword(s):  
Social Justice ◽  
Early Childhood ◽  
Children's Literature ◽  
Cultural Diversity ◽  
Day Care ◽  
Children’S Literature ◽  
Long Day ◽  
Day Care Centres ◽  
Book Collections ◽  
The Impact

The importance of recognising, valuing and respecting a child’s family, culture, language and values is central to socially just education and is increasingly articulated in educational policy worldwide. Inclusive children’s literature can support children’s human rights and contribute to equitable and socially just outcomes for all children. However, evidence suggests many educational settings provide monocultural book collections which are counterproductive to principles of diversity and social justice. Further, that educators’ understandings and beliefs about diversity can contribute to inequitable provision and use of diverse books and to inequitable outcomes of book sharing for many children. This paper reports on a larger study investigating factors and relationships influencing the use of children’s literature to support principles of cultural diversity in the kindergarten rooms of long day care centres. The study was conducted within an ontological perspective of constructivism and an epistemological perspective of interpretivism informed by sociocultural theory. A mixed methods approach was adopted, and convergent design was employed interpret significant relationships and their meanings. Twenty-four educators and 110 children from four long day care centres in Western Australia participated. Data were collected through semi-structured interviews, video-based observations, field notes, document analysis and a book audit. This study firstly identified that current book collections in kindergarten rooms of long day care centres promote mono-cultural viewpoints and ‘othering’ of minority groups through limited access to books portraying inclusive and authentic cultural diversity. Secondly, that educators had limited understandings of the role of literature in acknowledging and valuing diversity and rarely used it to promote principles of diversity, resulting in a practice of “othering” those from minority group backgrounds. The key challenges which emerged from the study concerned beliefs, understanding and confidence of educators about diversity and inclusion, and the impact of these on their approaches to promoting principles of diversity through the use of children’s books. This research contributes to discussion on the value of children’s literature in achieving international principles of diversity. These findings have important social justice implications. The outcomes of this study have implications for educators, policy makers, early childhood organisations and those providing higher education and training for early childhood educators.

Characteristics of educators’ talk about decontextualised events

2020 ◽  
Vol 45 (4) ◽  
pp. 362-376
Author(s):  
Rebecca Andrews ◽  
Penny Van Bergen
Keyword(s):  
Communication Skills ◽  
Future Event ◽  
Time Points ◽  
Long Day ◽  
Future Events ◽  
Day Care Centres ◽  
Highly Correlated ◽  
Children’S Thinking ◽  
Sydney Australia

This study investigated the characteristics of educators’ talk about decontextualised events with young children in seven early childhood long day care centres in Sydney, Australia. Educators were partnered with up to six children aged between 27 and 60 months. Across two time points, 85 educator–child dyads discussed past and future events. Educators’ use of questions, contextual statements, evaluations and prompts and children’s use of questions, open-ended responses, yes-no responses and spontaneous information statements were examined. Educators’ evaluative statements were highly correlated and educators’ questions were moderately correlated with children’s open-ended responses in past event conversations. Educators’ evaluative statements were highly correlated with children’s open-ended responses in future event conversations and were the only significant predictor for children’s talk. Given the important role of educators in scaffolding children’s thinking and communication skills, the recommended strategies for educators’ talk in decontextualised conversations include: sharing the conversational load, making frequent contextual statements and following the child’s lead/interests.

scholarly journals Breeding of Buckwheat for Usage of Sprout and Pre-Harvest Sprouting Resistance

Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 997
Author(s):  
Tatsuro Suzuki ◽  
Takahiro Hara ◽  
Kenjiro Katsu
Keyword(s):  
Subsequent Growth ◽  
Local Economies ◽  
Cereal Grain ◽  
The World ◽  
New Varieties ◽  
Sprouting Resistance ◽  
Sprout Growth ◽  
Noodle Quality ◽  
Buckwheat Flour

Buckwheat is recognized as an important traditional crop and supports local economies in several regions around the world. Buckwheat is used, for example, as a cereal grain, noodle and bread. In addition, buckwheat is also used as a sprout or a young seedling. For these foods, sprouting is an important characteristic that affects food quality. For foods made from buckwheat flour, pre-harvest sprouting may decrease yield, which also leads to the deterioration of noodle quality. Breeding buckwheat that is resistant to pre-harvest sprouting is therefore required. Germination and subsequent growth are also important characteristics of the quality of sprouts. Although buckwheat sprouts are the focus because they contain many functional compounds, such as rutin, several problems have been noted, such as thin hypocotyls and husks remaining on sprouts. To date, several new varieties have been developed to resolve these quality issues. In this review, we summarize and introduce research on the breeding of buckwheat related to quality, sprouting and subsequent sprout growth.

scholarly journals Effects of circadian clock and light on melatonin concentration in Hypericum perforatum L. (St. John’s Wort)

2020 ◽  
Vol 61 (1) ◽  
Author(s):  
Ming-Hsiu Chung ◽  
Tzu-Shing Deng
Keyword(s):  
High Performance ◽  
Hypericum Perforatum ◽  
Fresh Weight ◽  
Melatonin Concentration ◽  
Long Day ◽  
Spatiotemporal Regulation ◽  
Circadian Time ◽  
Hypericum Perforatum L ◽  
Pharmaceutical Industries ◽  
Oriented Research

Abstract Background Melatonin acts as a signaling hormone and entraining agent in many organisms. We studied the spatiotemporal regulation and influence of light (photoperiods, intensities, and spectral qualities) on melatonin concentration in the medicinal herb Hypericum perforatum L. Furthermore, melatonin concentrations in the leaves of eight species of the Hypericum genus were compared and analyzed using high-performance liquid chromatography. Results Melatonin concentration was found to be the highest in its flowers and leaves. The leaves exhibited a rhythmic variation in melatonin concentration of approximately 24 h under both light–dark entrained (Zeitgeber time) and constant light [circadian time (CT)] conditions, with melatonin concentration peaking at approximately CT6 in the middle of the subjective day. Melatonin concentration was influenced significantly by not only photoperiods but also applied light’s wavelength and intensity. It was approximately six times higher under long-day conditions (18-h light:6-h dark) than under short-day photoperiods (10-h light:14-h dark) and was the highest (131 μg/g fresh weight [FW]) under treatment with blue light at an intensity of 45 µmol·m2/s of photons. The melatonin concentration of the two examined Hypericum spp., namely H. kouytchense Lev. and H. coris L., were approximately twice that of H. perforatum L. Conclusion Our findings provide first insights on melatonin-related functions and mechanisms in the circadian system of H. perforatum and useful resources for further melatonin-oriented research and possible applications in agriculture and pharmaceutical industries.

Phytoplankton Adaptation to Environmental Stresses from Toxicants, Nutrients, and Pollutants — a Warning

1976 ◽  
Vol 33 (9) ◽  
pp. 2089-2096 ◽  
Author(s):  
John G. Stockner ◽  
Naval J. Antia
Keyword(s):  
Environmental Protection ◽  
Pollutant Concentration ◽  
Subsequent Growth ◽  
Short Term ◽  
Present Evidence ◽  
Test Chemical ◽  
Successful Adaptation ◽  
Shock Response ◽  
Chronic Pollution

Examples are cited from the literature of phytoplankton-related pollution and nutrition studies where the possibility of successful adaptation and subsequent growth could have been overlooked because of insufficient duration of algal exposure to the pollutant or nutrient tested. We present evidence from our investigations where: a) initial algal exposures as long as 20–40 days to the pollutant or alternative nutrient may be required for successful adaptation, and b) phytoplankters initially tolerating only a low level of pollutant concentration could be trained to accept severalfold higher levels by repeated exposure to gradually increasing pollutant concentration A plea is made for future investigators to recognize the importance of long-term bioassays ascertaining algal potential for adaptation, in order that their results may be ecologically realistic for the purpose of environmental protection against chronic pollution and eutrophication. The short-term "shock" response should be clearly distinguished from the long-term habituation response of phytoplankters to the test chemical in these bioassays. Possible problems raising questionable objections to the long-term bioassay approach are discussed.

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