scholarly journals The endogenous responses during the flowering stage of Torenia fournieri L. under LED light

2020 ◽  
Vol 16 (4) ◽  
pp. 659-667
Author(s):  
Tuan Trong Tran ◽  
Doan Do Tuong Han ◽  
Nguyen Huu Ho ◽  
Duong Tan Nhut
Keyword(s):  
Net Photosynthetic Rate ◽  
Blue Light ◽  
Photosynthetic Rate ◽  
Light Emitting Diode ◽  
Sugar Content ◽  
Central Zone ◽  
Peripheral Zone ◽  
Torenia Fournieri ◽  
Flowering Stage ◽  
Carbohydrate Source

The quality of light has played an important role not only in the vegetative growth, but also in the reproductive stage of the plant. Normally, the endogenous transformation has hardly been observed under the general condition. This study analyzed the endogenous changes, which were particularly influenced by the spectrum of light emitting diode (LED) with induction flowering time from 30th to 40th day. In the 40th day of the flowering process, when the average number of flower buds get the highest, endogenous carbohydrate content was decreased. However, in this phase, plants need more energy; therefore, the net photosynthetic rate tends to increase in order to supply energy for flowering. Throughout 40 days of culture, the net photosynthetic rate had an increase in the concentration of CO2. In particular, it reached the peak when being induced under the light combination ratio 7:3 of red and blue light (0.222 µmol mol-1 h-1). The sugar content also followed the same trajectory; however, it dropped at the end of the period. Among all the experiments, the ratio of red and blue light 5:5 resulted in the highest content of endogenous carbohydrate source (722.30 µg g-1). Moreover, the morphological anatomy of shoot apical meristem in flowering stage was also studied. The floral transition at meristem and floral architecture is as similar as that of Arabidopsis. A typical flower of T. fournieri also consists of a sequence: sepals – petals – stamens – carpels. The SAM is organized into three different zones such as the central zone (CZ), the peripheral zone (PZ) surrounding the CZ and the rib zone (RZ) underneath the CZ.

IRRIGATION, SPACING AND CULTIVAR EFFECTS ON NET PHOTOSYNTHETIC RATE, DRY MATTER PARTITIONING AND PRODUCTIVITY OF RICE UNDER SYSTEM OF RICE INTENSIFICATION IN MOLLISOLS OF NORTHERN INDIA

2013 ◽  
Vol 49 (4) ◽  
pp. 504-523 ◽  
Author(s):  
ANCHAL DASS ◽  
SUBHASH CHANDRA
Keyword(s):  
Grain Yield ◽  
Net Photosynthetic Rate ◽  
Photosynthetic Rate ◽  
Dry Matter ◽  
Field Experiments ◽  
Water Productivity ◽  
System Of Rice Intensification ◽  
Dry Matter Accumulation ◽  
Flowering Stage ◽  
Rice Intensification

SUMMARYField experiments were conducted on a Typic Hapludoll (Mollisols) soil in the Indo-Gangetic Plains of India during the 2008 and 2009 rainy seasons to (1) find out the effect of irrigation schedules and plant spacing on physiological parameters, yield and water productivity of two rice cultivars under System of Rice Intensification (SRI), and (2) compare the performance of SRI with conventional transplanting (CT). Treatments under SRI included 12 combinations of three irrigation schedules, viz. irrigation at 1, 3 and 5 day(s) after disappearance of ponded water (DADPW), two spacing intervals (20 × 20 cm and 25 × 25 cm) and two cultivars (‘Pant Dhan 4’ and ‘Hybrid 6444’). The two control treatments were the CT of each cultivar. The experiment was set in a factorial randomized complete block design replicated thrice. The net photosynthetic rate (NPR) of the topmost fully expanded leaf at tillering and that of flag-leaf at flowering stage was affected significantly by irrigation schedules. Irrigating rice crop at 1 or 3 DADPW, being at par with each other, recorded significantly higher NPR than 5 DADPW. The increase in NPR at 1 and 3 DADPW was 17.1% and 8.4% at tillering and 13.6% and 6.1% at flowering stage, respectively, compared with that at 5 DADPW (tillering: 12.78 μmol CO2 m−2 S−1, flowering: 16.01 μmol CO2 m‑2 S−1). At closer spacing (20 × 20 cm) the cultivars did not differ significantly for NPR; however, at wider spacing (25 × 25 cm), ‘Hybrid 6444’ showed significantly higher NPR than ‘Pant Dhan 4’. Between two methods, SRI recoded higher NPR. Dry matter accumulation (DMA) in leaves and grains declined with delay in irrigation from 1 to 5 DADPW. Wider spacing significantly enhanced DMA in stems and grains. ‘Hybrid 6444’ showed higher DMA in all plant parts than ‘Pant Dhan 4’. Grain yield was not affected significantly by irrigation schedules in 2008, while in 2009, irrigation at 1 and 3 DADPW resulted in 12.8% and 8.0% higher grain yield, respectively, than 5 DADPW (5.84 t ha−1). Wider spacing was superior to closer spacing. SRI improved grain yield by 16.9% and water productivity by 18.5% over CT.

scholarly journals Morphological and Physiological Responses of Morus alba Seedlings under Different Light Qualities

2016 ◽  
Vol 44 (2) ◽  
pp. 382-392 ◽  
Author(s):  
Juwei HU ◽  
Xin DAI ◽  
Guangyu SUN
Keyword(s):  
Net Photosynthetic Rate ◽  
Leaf Area ◽  
Blue Light ◽  
Photosynthetic Rate ◽  
Photochemical Efficiency ◽  
Morus Alba ◽  
Leaf Thickness ◽  
Stem Length ◽  
Leaf Mass Per Area ◽  
Palisade Tissue

Light quality can influence the photosynthetic characteristics, morphology and physiological processes of plants. To investigate the effects of different light qualities (white light, W; red light, R; blue light, B; mixture of red and blue light, RB) of light emitting diodes (LEDs) and white cold fluorescent lamp on the growth and morphology of fruiting mulberry plants (Morus alba L. cv. ‘Longsang No.1’), fruiting mulberry plants were grown under different light qualities: W, R, B and RB of the same photosynthetic photo flux density (PPFD; 100 μmol m-2 s-1) for 20 d. Our results showed that stem length and leaf area of plants grown under R were the highest. However, stem length and leaf area of plants grown under B were lowest. Dry weights (DW), leaf mass per area (LMA), chlorophyll a/b ratio, soluble protein content, sucrose and starch content, and total leaf nitrogen (N) content of plants grown under R were the lowest. Net photosynthetic rate (Pn), stomatal conductance (gs), and actual photochemical efficiency of PSII (ΦPSII) of plants grown under RB were similar to plants grown under W. Net photosynthetic rate (Pn) and ΦPSII of plants grown under R and B were lower than plants grown under W and RB. Antioxidant enzymes activity of plants grown under R, RB and B were higher than plants grown under W. The number of leaf stomata, leaf thickness, palisade tissue length and spongy tissue length were the lowest in plants grown under R. The number of leaf stomata, leaf thickness and palisade tissue length of plants grown under RB and B were higher than plants grown under R. The results of this study indicate that a certain ratio of mixed red and blue LEDs light can reduce adverse effects of monochromatic red and blue LEDs light on fruiting mulberry growth and development.

Diurnal variation in net photosynthetic rate and influencing environmentalfactors of Elaeagnus mollis Diels leaf

2009 ◽  
Vol 17 (3) ◽  
pp. 474-478
Author(s):  
Qun-Long LIU ◽  
Chan-Juan NING ◽  
Duo WANG ◽  
Guo-Liang WU ◽  
Hong-Mei ZHANG ◽  
...  
Keyword(s):  
Diurnal Variation ◽  
Net Photosynthetic Rate ◽  
Photosynthetic Rate ◽  
Elaeagnus Mollis

scholarly journals Changes in peanut canopy structure and photosynthetic characteristics induced by an arbuscular mycorrhizal fungus in a nutrient-poor environment

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yinli Bi ◽  
Huili Zhou
Keyword(s):  
Net Photosynthetic Rate ◽  
Leaf Area ◽  
Photosynthetic Rate ◽  
Mycorrhizal Fungus ◽  
Canopy Structure ◽  
Arbuscular Mycorrhizal ◽  
Photosynthetic Characteristics ◽  
Total Leaf Area ◽  
Tiller Angle ◽  
Amf Inoculation

AbstractA well-developed canopy structure can increase the biomass accumulation and yield of crops. Peanut seeds were sown in a soil inoculated with an arbuscular mycorrhizal fungus (AMF) and uninoculated controls were also sown. Canopy structure was monitored using a 3-D laser scanner and photosynthetic characteristics with an LI-6400 XT photosynthesis system after 30, 45 and 70 days of growth to explore the effects of the AMF on growth, canopy structure and photosynthetic characteristics and yield. The AMF colonized the roots and AMF inoculation significantly increased the height, canopy width and total leaf area of the host plants and improved canopy structure. AMF reduced the tiller angle of the upper and middle canopy layers, increased that of the lower layer, reduced the leaf inclination of the upper, middle and lower layers, and increased the average leaf area and leaf area index after 45 days of growth, producing a well-developed and hierarchical canopy. Moreover, AMF inoculation increased the net photosynthetic rate in the upper, middle and lower layers. Plant height, canopy width, and total leaf area were positively correlated with net photosynthetic rate, and the inclination angle and tiller angle of the upper leaves were negatively correlated with net photosynthetic rate. Overall, the results demonstrate the effects of AMF inoculation on plant canopy structure and net photosynthetic rate.

The influence of red and blue light on the rate of photosynthesis and the CO2 compensation point at various oxygen concentrations

1970 ◽  
Vol 48 (6) ◽  
pp. 1251-1257 ◽  
Author(s):  
N. P. Voskresenskaya ◽  
G. S. Grishina ◽  
S. N. Chmora ◽  
N. M. Poyarkova
Keyword(s):  
Nicotiana Tabacum ◽  
Blue Light ◽  
Photosynthetic Rate ◽  
Prolonged Exposure ◽  
Red Light ◽  
Compensation Point ◽  
Gas Analyzer ◽  
Co2 Compensation Point ◽  
Rate Of Photosynthesis ◽  
Light Inhibition

Apparent photosynthesis of attached leaves of Phaseolus vulgaris, Vicia faba, Pisum sativum, and Nicotiana tabacum at various intensities of blue and red light was measured by infrared CO2 gas analyzer in a closed system. Simultaneously the CO2 compensation point was measured.It was found that light-limited photosynthetic rate in blue light was equal to or more than that in red light. Inhibition of photosynthesis, which sometimes occurred at light-saturated intensities of blue light, could be avoided by addition of red light, prolonged exposure of the plants to blue light, or by lowering the O2 concentration. Accordingly, the increase of photosynthetic rate due to change of O2 concentration from 21 to 3% O2 is higher in blue light only when photosynthesis is inhibited by blue light at 21% O2. The data on the action of blue and red light on the CO2 compensation point seems to exclude the activation of photorespiration by blue light.The possible effects of blue light on apparent photosynthesis are discussed on the basis of the results presented.

scholarly journals In vitro and in vivo Efficacy of New Blue Light Emitting Diode Phototherapy Compared to Conventional Halogen Quartz Phototherapy for Neonatal Jaundice

2005 ◽  
Vol 20 (1) ◽  
pp. 61 ◽  
Author(s):  
Yun Sil Chang ◽  
Jong Hee Hwang ◽  
Hyuk Nam Kwon ◽  
Chang Won Choi ◽  
Sun Young Ko ◽  
...  
Keyword(s):  
Blue Light ◽  
Neonatal Jaundice ◽  
Light Emitting Diode ◽  
In Vivo Efficacy ◽  
Light Emitting

scholarly journals Operando direct observation of spin-states and charge-trappings of blue light-emitting-diode materials in thin-film devices

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Fumiya Osawa ◽  
Kazuhiro Marumoto
Keyword(s):  
Blue Light ◽  
High Performance ◽  
Density Functional ◽  
Light Emitting Diode ◽  
Green Light ◽  
Spin States ◽  
Light Emitting ◽  
Full Color ◽  
Color Displays ◽  
Materials Used

Abstract Spin-states and charge-trappings in blue organic light-emitting diodes (OLEDs) are important issues for developing high-device-performance application such as full-color displays and white illumination. However, they have not yet been completely clarified because of the lack of a study from a microscopic viewpoint. Here, we report operando electron spin resonance (ESR) spectroscopy to investigate the spin-states and charge-trappings in organic semiconductor materials used for blue OLEDs such as a blue light-emitting material 1-bis(2-naphthyl)anthracene (ADN) using metal–insulator–semiconductor (MIS) diodes, hole or electron only devices, and blue OLEDs from the microscopic viewpoint. We have clarified spin-states of electrically accumulated holes and electrons and their charge-trappings in the MIS diodes at the molecular level by directly observing their electrically-induced ESR signals; the spin-states are well reproduced by density functional theory. In contrast to a green light-emitting material, the ADN radical anions largely accumulate in the film, which will cause the large degradation of the molecule and devices. The result will give deeper understanding of blue OLEDs and be useful for developing high-performance and durable devices.

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