scholarly journals Cumulative Effects of Ultraviolet Radiation and Photosyntheically Active Radiation on Phycobiliproteins of A Hot-Spring Cyanobacatrium Nostoc sp. strain HKAR-2

2016 ◽  
Vol 4 (3) ◽  
pp. 247-253
Author(s):  
Vinod K. Kannaujiya ◽  
Akhlaqur Rahman ◽  
. Adinath ◽  
Arun S. Sonker ◽  
Jainendra Pathak ◽  
...  
Keyword(s):  
Ultraviolet Radiation ◽  
Environmental Conditions ◽  
Photosynthetically Active Radiation ◽  
Biomedical Applications ◽  
Hot Spring ◽  
Ultraviolet B ◽  
Cumulative Effects ◽  
Key Factors ◽  
Active Radiation ◽  
Continuous Induction

Cyanobacteria are cosmopolitan in distribution and have adapted to diverse habitats. Adaptation of cyanobacteria is one of the key factors to withstand harsh environmental conditions. We have investigated the effects of photosynthetically active radiation (PAR; 400–700 nm), ultraviolet-B (UV-B; 280–315 nm) radiation and PAR+UV-B radiations on phycobiliproteins (PBPs) of a hot-spring cyanobacterium Nostoc sp. HKAR-2. There was a continuous induction of both phycoerythrin (PE) and phycocyanin (PC) after exposure of PAR up to 300 min. However, there was an induction in the synthesis of both PE and PC up to 240 min exposure of UV-B and PAR+UV-B radiations. Further exposure showed decline in the synthesis due to rapid uncoupling, bleaching and degradation of PBPs. Similarly, emission fluorescence also showed an induction with a shift towards longer wavelengths after 240 min of UV-B and PAR+UV-B exposure. These results indicate that short duration of UV radiation may promote the synthesis of PBPs that can be utilized in various biotechnological and biomedical applications. Int J Appl Sci Biotechnol, Vol 4(3): 247-253

scholarly journals Sowing operation direction and population densities in corn growing

2019 ◽  
Vol 23 (3) ◽  
pp. 183-187
Author(s):  
Rafael D. G. Corrêa ◽  
Carlos E. A. Furlani ◽  
Cristiano Zerbato ◽  
Danilo T. de Oliveira ◽  
Rafael H. de F. Noronha ◽  
...  
Keyword(s):  
Environmental Conditions ◽  
Photosynthetically Active Radiation ◽  
Corn Yield ◽  
Population Densities ◽  
Plant Populations ◽  
Hybrid Corn ◽  
Active Radiation ◽  
Plant Densities ◽  
Lower Plant ◽  
East West

ABSTRACT Among the factors that may influence corn yield are sowing operation direction and plant population, since they alter the shade index between crop rows, and consequently the efficiency of interception of the photosynthetically active radiation by the leaves of plants. The aim of this study was to evaluate the influence of sowing direction and plant populations on P2830VYH hybrid corn yield. The experiment was conducted at the facilities of FCAV-UNESP, latitude 21º 14’ S and longitude 48º 16’ W in Jaboticabal (SP). The treatments were composed of three sowing directions (North-South, Northeast-Southwest, and East-West) and three population densities (40,000, 60,000 and 80,000 plants ha-1). The treatment with 80,000 plants ha-1 had the lowest cost per sack of corn and profitability 21% higher than that of the treatment with 60,000 plants ha-1, and 45% higher than that of the treatment with 40,000 plants ha-1. Sowing direction had no influence on grain yield when environmental conditions were favorable to the development of the crop. Lower plant densities lead to higher individual results in relation to the number of cobs, length of cobs and number of grains per row.

Effects of Natural Radiation, Photosynthetically Active Radiation and Artificial Ultraviolet Radiation-B on the Chloroplast Organization and Metabolism ofPorphyra acanthophoravar.brasiliensis(Rhodophyta, Bangiales)

2012 ◽  
Vol 18 (6) ◽  
pp. 1467-1479 ◽  
Author(s):  
Zenilda L. Bouzon ◽  
Fungyi Chow ◽  
Carmen S. Zitta ◽  
Rodrigo W. dos Santos ◽  
Luciane C. Ouriques ◽  
...  
Keyword(s):  
Ultraviolet Radiation ◽  
Photosynthetically Active Radiation ◽  
Laser Scanning ◽  
Reductase Activity ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Ambient Conditions ◽  
Natural Radiation ◽  
Active Radiation ◽  
Ultraviolet Radiation B

AbstractWe undertook a study ofPorphyra acanthophoravar.brasiliensisto determine its responses under ambient conditions, photosynthetically active radiation (PAR), and PAR+UVBR (ultraviolet radiation-B) treatment, focusing on changes in ultrastructure, and cytochemistry. Accordingly, control ambient samples were collected in the field, and two different treatments were performed in the laboratory. Plants were exposed to PAR at 60 μmol photons m−2s−1and PAR + UVBR at 0.35 W m−2for 3 h per day during 21 days ofin vitrocultivation. Confocal laser scanning microscopy analysis of the vegetative cells showed single stellate chloroplast in ambient and PAR samples, but in PAR+UVBR-exposed plants, the chloroplast showed alterations in the number and form of arms. Under PAR+UVBR treatment, the thylakoids of the chloroplasts were disrupted, and an increase in the number of plastoglobuli was observed, in addition to mitochondria, which appeared with irregular, disrupted morphology compared to ambient and PAR samples. After UVBR exposure, the formation of carpospores was also observed. Plants under ambient conditions, as well as those treated with PAR and PAR+UVBR, all showed different concentrations of enzymatic response, including glutathione peroxidase and reductase activity. In summary, the present study demonstrates thatP. acanthophoravar.brasiliensisshows the activation of distinct mechanisms against natural radiation, PAR and PAR+UVBR.

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