scholarly journals The role of far-red light (FR) in photomorphogenesis and its use in greenhouse plant production

2020 ◽  
Vol 116 (1) ◽  
pp. 93
Author(s):  
Bojka KUMP
Keyword(s):  
Growth And Development ◽  
Light Quality ◽  
Red Light ◽  
Spectral Composition ◽  
Plant Production ◽  
Recent Developments ◽  
Long Time ◽  
Supplementary Lighting ◽  
Quality Of Products

<p>Light energy is one of the most important factors regulating the growth and development of plants. In greenhouses and other controlled- environments in which the natural radiation intensities are often low, plant production relies on supplementary lighting to optimize the photosynthesis, increase production levels, and enable year-round production. For a long time, the research related to artificial lighting sources focused on the optimization of the efficiency of use for photosynthesis. The quality of light in plant production has been widely addressed only recently with the development of advanced LED technology that is energy efficient and enables the control of the spectral composition of light. Red and far-red light are sensed by the phytochromes that trigger several morphological and developmental processes that impact productivity and yield quality. Thus, to efficiently exploit all the advantages of LEDs and to develop LED arrays for specific plant applications, it is essential to understand thoroughly how light quality influences plant growth and development. This paper presents an overview of the recent developments in light quality manipulation, focusing on far-red light and the R: FR ratio, to improve yield and quality of products and to manage plant architecture and flowering in vegetable and ornamental horticulture.</p>

scholarly journals Effects of Light on Growth and Flowering of Rosa hybrids `Mercedes'

1995 ◽  
Vol 120 (4) ◽  
pp. 571-576 ◽  
Author(s):  
Frank M. Maas ◽  
Edwin J. Bakx
Keyword(s):  
Light Quality ◽  
Day Treatment ◽  
Red Light ◽  
Spectral Composition ◽  
Dry Weight ◽  
Photon Flux ◽  
Short Treatment ◽  
Lateral Shoots ◽  
Single Shoot

Growth and flowering of shoots of `Mercedes' rose was investigated as a function of the level and spectral quality of photosynthetic photon flux (PPF). Experiments were performed with single-shoot plants decapitated above the two most basal leaves with five leaflets. The development of the two lateral shoots emerging from the axillary buds of these leaves was studied for 4 to 6 weeks. To discriminate between the effects of irradiance and light quality, plants were grown in growth chambers in which PPF and its spectral composition could be controlled. At a photoperiod of 12 hours, the length, weight, and flowering of the shoots strongly increased with irradiance. The growth and number of flowering shoots were always higher for the uppermost than for the second shoot. At the highest PPF (270 μmol·m-2·s-1), flowering occurred in 89% and 33% of the uppermost and second shoots, respectively. At an irradiance level of 90 μmol·m-2·s-1, these percentages were 6% and 0%. Although length and dry weight of both types of shoots were significantly increased by reducing the amount of blue light at constant PPF, flower development was not affected. In a second experiment, plants grown in white light (12 h/day) received a short treatment with low-intensity red or far-red `light at the end of each photoperiod. An end-of-day treatment with red light resulted in significantly more flowering shoots than far-red. The red far-red reversibility of this flowering response indicates the involvement of the photoreceptor phytochrome.

scholarly journals ANALYSIS OF USING DIFFERENTIATED APPROACH WHEN IRRIGATING AGRICULTURAL CROPS

2020 ◽  
Author(s):  
A. N. Babichev ◽  
◽  
A. A. Babenko ◽  
Keyword(s):  
Growth And Development ◽  
Irrigation System ◽  
Research Work ◽  
Climatic Conditions ◽  
Agricultural Crops ◽  
Critical Periods ◽  
Irrigation Regime ◽  
Agrochemical Properties ◽  
Quality Of Products

Purpose: to analyze the experience of Russian scientists in the field of application of a differentiated approach to agricultural crops irrigation. The overview of research work of domestic scientists on the use of an irrigation system in agriculture, in which the provision of agricultural crops with water to maintain a given level of the minimum water capacity will be carried out during the most critical periods of their growth and development is presented. During irrigation, the timing, frequency, irrigation rates depend on the level of groundwater occurrence, agrochemical properties of soils, weather and climatic conditions, phases of growth and development of crops. The application of a differentiated irrigation regime to maintain a given level of pre-irrigation moisture allows increasing the productivity of agricultural crops, the quality of products obtained while reducing irrigation and watering rates, the number of waterings. Conclusions. The study of the results of research work of domestic scientists in the field of influence of irrigation and the fertilization system on the yield and quality of agricultural products allows concluding that obtaining the planned yields is possible only if irrigation regimes are observed and the level of soil fertility is maintained by applying various fertilizers. The use of a differentiated approach to irrigation while maintaining a given level of pre-irrigation soil moisture during critical periods of crop development allows reducing irrigation water consumption and optimizing irrigation rates and their quantity. The study of a differentiated irrigation regime is promising now and in the near future, taking into account the deteriorating water supply in the territory of our country, associated with a change in weather and climatic conditions.

scholarly journals Identification and expression of the trehalose-6-phosphate synthase gene family members in tomato exposed to different light spectra

2017 ◽  
Vol 69 (1) ◽  
pp. 93-101
Author(s):  
Zexiong Chen ◽  
Juan Lou
Keyword(s):  
Plant Growth ◽  
Blue Light ◽  
White Light ◽  
Growth And Development ◽  
Light Quality ◽  
Red Light ◽  
Floral Transition ◽  
Stem Length ◽  
Pcr Analysis ◽  
Phosphate Synthase

Light is the source of energy for plants. Light wavelengths, densities and irradiation periods act as signals directing morphological and physiological characteristics during plant growth and development. To evaluate the effects of light wavelengths on tomato growth and development, Solanum lycopersicum (cv. micro-Tom) seedlings were exposed to different light-quality environments, including white light and red light supplemented with blue light (at ratios of 3:1 and 8;1, respectively). Tomatoes grown under red light supplemented with blue light displayed significantly shorter stem length, a higher number of flower buds and rate of fruit set, but an extremely late flowering compared to white-light-grown plants. To illustrate the mechanism underlying the inhibition of stem growth and floral transition mediated by red/blue light, 10 trehalose-6-phosphate synthase (TPS) genes were identified in tomato, and bioinformatics analysis was performed. qRT-PCR analysis showed that SlTPSs were expressed widely throughout plant development and SlTPS1 was expressed at extremely high levels in stems and buds. Further analysis of several flowering-associated genes and microRNAs showed that the expressions of SlTPS1, SlFT and miR172 were significantly downregulated in tomato grown under red and blue light compared with those grown under white light, whereas miR156 transcript levels were increased. A regulatory model underlying vegetative growth and floral transition regulated by light qualities is presented. Our data provide evidence that light quality strongly affects plant growth and phase transition, most likely via the TPS1-T6P signaling pathway.

Clouds and cloud immersion alter photosynthetic light quality in a temperate mountain cloud forest

Botany ◽  
2010 ◽  
Vol 88 (5) ◽  
pp. 462-470 ◽  
Author(s):  
Keith Reinhardt ◽  
William K. Smith ◽  
Gregory A. Carter
Keyword(s):  
Light Quality ◽  
Cloud Forest ◽  
Spectral Band ◽  
Red Light ◽  
High Elevation ◽  
Cloud Forests ◽  
Specific Effects ◽  
Open Canopy ◽  
Low Cloud

Light quantity and quality strongly influence plant ecophysiology, especially in cloud forests. Only a few studies have investigated the quantitative effects of clouds on incident sunlight, and almost no studies have explored the specific effects of cloud immersion on light quality. In the present study, the spectral quantity and quality of sunlight during sunny (S), low cloud (LC), and cloud immersed (CI) days in open canopy and understory microsites are compared in high elevation cloud forests in the southern Appalachian Mountains, USA. Cumulative daily radiation measured on CI days was 85% less than on S days at open sites, but about the same as S days in understory sites. LC and CI conditions enhanced blue light by 5%–15% in open sites, but decreased it by 25%–60% in understory sites. In cloudy conditions, red light decreased by 6%–11% in open areas and increased by 25%–30% in understory sites. Cloudiness also resulted in important changes in spectral band ratios, and was associated with light diffusivity. Thus, cloud regimes had a strong influence on the photosynthetic light quality of incident sunlight.

scholarly journals INFLUENCE OF MICROBIC PREPARATIONS AND MINERAL FERTILIZERS ON THE DISEASES RESISTANCE AND PRODUCTIVITY OF SOYBEAN CULTIVARS

2011 ◽  
Vol 13 ◽  
pp. 59-69
Author(s):  
V.P. Derevyanskyi ◽  
O.S. Vlasyuk ◽  
D.V. Krutylo ◽  
T.M. Kovalevska ◽  
S.P. Nadkernychnyyi ◽  
...  
Keyword(s):  
Bradyrhizobium Japonicum ◽  
Growth And Development ◽  
Mineral Fertilizers ◽  
Soybean Cultivars ◽  
Increase Productivity ◽  
Quality Of Products ◽  
Resistance To Diseases

Influence of complex of factors (mineral fertilizers, treatment of seed and crops with microbiological preparations) on plants resistance to diseases and productivity of different soybean cultivars was studied. Compositions, which allow to improve plants growth and development, as well as decrease diseases prevalence and increase productivity and quality of products were selected. The models of soybean cultivars with microorganisms – Glуcine max–Bradyrhizobium japonicum were created.

scholarly journals ДЖЕРЕЛА ГОСПОДАРСЬКИХ ТА СЕЛЕКЦІЙНО-ЦІННИХ ОЗНАК ДЛЯ СЕЛЕКЦІЇ ГРЕЧКИ ЗВИЧАЙНОЇ (Fagopyrum esculentum Moench.)

2017 ◽  
pp. 48-55
Author(s):  
О. В. Тригуб ◽  
В. В. Ляшенко
Keyword(s):  
Fagopyrum Esculentum ◽  
Common Origin ◽  
Plant Production ◽  
Morphological Parameters ◽  
Study Methods ◽  
Experimental Station ◽  
Quality Of Products ◽  
Fagopyrum Esculentum Moench

У статті наведено результати вивчення гречки звичайної різного походження із Національної колекції України протягом 2014–2016 років в Устимівській дослідній станції рослинництва за характеристиками господарської придатності та морфологічними показниками. Застосовані методики вивчення та опису матеріалу дали змогу диференціювати колекційний матеріал і виділити найбільш цінний, як джерела господарських та селекційно-цінних ознак за різними напрямками селекційного використання – за урожайністю та її складовими, якістю продукції. The article presents the results of the study of buckwheat of common origin from the National Collection of Ukraine for 2014–2016 years in Ustymivka Experimental Station of Plant Production on the economic characteristics and morphological parameters. Used study methods and description of the material allowed to differentiate collection material and identify the most valuable as a source of economic and selection-valuable traits in different directions selective use – for yield and its components, quality of products.

scholarly journals The Effect of Customer Satisfaction on Customers Loyalty at the Green Mart Supermarket in Namrole City

2021 ◽  
Author(s):  
M Chairul Basrun Umanailo
Keyword(s):  
Customer Satisfaction ◽  
Secondary Data ◽  
Sampling Technique ◽  
Primary Data ◽  
Literature Study ◽  
Long Time ◽  
Quality Of Products ◽  
The City ◽  
Positive Effect

This study aims to determine the effect of customer satisfaction on buyer loyalty at Green Mart in Namrolesupermarkets. This research is quantitative. This research took place in the city of Namrole with the object of research at the Green Mart Supermarket. Sources of data in this study are primary data and secondary data. The data collection techniques in this research were survey and literature study. Sampling was done by non-probability sampling with a purposive sampling technique. The data analysis in this study used regression analysis. This analysis is used to examine the effect of customer satisfaction on loyalty. The results showed that customer satisfaction has a positive effect on loyalty. This implies that, if customer satisfaction increases, loyalty also tends to increase, if a customer is satisfied with the value provided by the products sold and the services received from Supermarkets, Green Mart is very likely to become loyal customers to Supermarkets. Green Mart for a long time. However, if customer satisfaction decreases, loyalty tends to decrease. Increased customer satisfaction is influenced by several factors, including the product and quality of products sold by various stores and according to the market tastes of shop consumers, friendliness, speed of service, and ease of transactions.

scholarly journals Growth and Energy Use Efficiency of Grafted Tomato Transplants as Affected by LED Light Quality and Photon Flux Density

Agriculture ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 816
Author(s):  
Jianfeng Zheng ◽  
Peidian Gan ◽  
Fang Ji ◽  
Dongxian He ◽  
Po Yang
Keyword(s):  
Energy Use ◽  
Light Quality ◽  
Red Light ◽  
Electrical Energy ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Red Led ◽  
Use Efficiency ◽  
Led Lights

This study was conducted to compare the effects of broad spectrum during the whole seedling period and photon flux density (PFD) in the healing stage on the growth and energy use efficiency of grafted tomato (Lycopersicon esculentum Mill.) transplants in a plant factory. Fluorescent lights, white LED lights, and white plus red LED lights were applied at the growth processes of grafted tomato transplants from germination of rootstock and scion to post-grafting. Three levels of PFD (50, 100, 150 μmol m−2 s−1) were set in the healing stage under each kind of light quality. The results indicated that the growth and quality of grafted tomato transplants under different broad spectrums were influenced by the ratio of red to blue light (R/B ratio) and the ratio of red to far-red light (R/FR ratio). A higher R/B ratio was beneficial to total dry matter accumulation, but excessive red light had a negative effect on the root to shoot ratio and the seedling quality index. The higher blue light and R/FR ratio suppressed stem extension synergistically. The LED lights had good abilities to promote plant compactness and leaf thickness in comparison with fluorescent lights. The plant compactness and leaf thickness increased with the increase in daily light integral in the healing stage within a range from 2.5 to 7.5 mol m−2 d−1 (PFD, 50 to 150 μmol m−2 s−1). Compared to fluorescent lights, the LED lights showed more than 110% electrical energy saving for lighting during the whole seedling period. Higher PFD in the healing stage did not significantly increase the consumption of electric power for lighting. White plus red LED lights with an R/B ratio of 1.2 and R/FR ratio of 16 were suggested to replace fluorescent lights for grafted tomato transplants production considering the high quality of transplants and electrical energy saving, and PFD in the healing stage was recommended to be set to 150 μmol m−2 s−1.

Control by Light Quality of Chlorophyll Synthesis in the Brown Alga Desmarestia aculeata

1991 ◽  
Vol 46 (7-8) ◽  
pp. 542-548 ◽  
Author(s):  
F. López-Figueroa
Keyword(s):  
Blue Light ◽  
Light Quality ◽  
Red Light ◽  
Green Light ◽  
Chlorophyll Synthesis ◽  
Natural Conditions ◽  
Light Pulses ◽  
Light Effects ◽  
Starvation Conditions

Abstract The chlorophyll synthesis in the brown algae Desmarestia aculeata is affected by light quality and by the nutrient state in the medium before the illumination. Pulses of 5 min of red, green and blue light together with 200 μM nitrate in plants growing under natural conditions deter­ mined similar induction of chlorophyll synthesis. However, when the plants were incubated previously under starvation conditions the light effect was different. The induction of chlorophyll synthesis was greater after blue and green light than after red light pulses. Red-light photoreceptor was only involved in the chlorophyll synthesis under no nutrient limitations and under starvation conditions after previous illumination with blue light followed by far-red light. The induction of chlorophyll synthesis by green and blue light pulses applied together with nitrate was greater when the algae were incubated in starvation conditions than in natural conditions (normal nutrient state). Because all light effects were partially reversed by far-red light the involvement of a phyto-chrome-like photoreceptor is proposed. In addition, a coaction between blue-and a green-light photoreceptors and phytochrome is suggested.

Sign in / Sign up

Export Citation Format

Share Document