COMPARACIÓN DE CUBIERTAS DE INVERNADEROS EN RELACIÓN CON CRECIMIENTO Y RENDIMIENTO DE TOMATE

El cultivo en invernadero permite obtener rendimientos mayores que los obtenidos a campo abierto, debido a un control mejor del ambiente. Bajo la hipótesis de que el color y las características del material de cubierta en invernadero de tipo túnel para producción de tomate afectan la transmisión de la radiación solar recibida por las plantas y por lo tanto crecimiento y rendimiento; el objetivo del estudio fue evaluar intensidad y distribución espectral de la radiación solar transmitida (Photosynthetic active radiation, PAR) a través de cuatro cubiertas de invernadero con características físicas y color diferentes, sobre contenido relativo de clorofila, tasa de fotosíntesis, crecimiento y rendimiento de un cultivo de tomate (Solanum lycopersicum L.). Para medir la intensidad de la radiación solar (400 a 700 nm) transmitida por cada cubierta se hizo la instalación de sensores quantum en el interior de invernaderos de tipo túnel; se determinó con un espectro radiómetro la característica espectral en la misma banda de radiación solar. El efecto de las cubiertas se analizó con un diseño completamente al azar con las repeticiones por tratamiento dentro de cada invernadero. Las plantas en los túneles con cubiertas de polietileno difuso de alta densidad de pigmentación roja y azul recibieron menos radiación solar en la banda de 400 a 700 nm de longitud de onda. Además, la radiación de 400 a 550 nm recibida por las plantas en el invernadero con cubierta de pigmentación roja fue mucho menor que la recibida por plantas bajo otras cubiertas. Las plantas en el invernadero con cubierta de polietileno azul recibieron menos radiación solar de la amplitud 600 a 700 nm. Esto no afectó el contenido de clorofila ni la tasa de asimilación de bióxido de carbono; sin embargo, hubo incremento significativo (p≤0.05) en altura de planta, pero con diámetro de tallo menor. Así como un rendimiento mayor, expresado en número de frutos por planta, peso y tamaño mayor de fruto en las plantas bajo túneles de polietileno con pigmentación roja y azul.

Improving Remote Sensing-based Estimation of Mangrove Forest Gross Primary Production by Quantifying Environmental Stressors: Sea Surface Temperature, Salinity, and Photosynthetic Active Radiation

Mangrove ecosystems play an important role in global carbon budget, however, the quantitative relationships between environmental drivers and productivity in these forests remain poorly understood. This study presented a remote sensing (RS)-based productivity model to estimate the light use efficiency (LUE) and gross primary production (GPP) of mangrove forests in China. Firstly, LUE model considered the effects of tidal inundation and therefore involved sea surface temperature (SST) and salinity as environmental scalars. Secondly, the downscaling effect of photosynthetic active radiation (PAR) on the mangrove LUE was quantified according to different PAR values. Thirdly, the maximum LUE varied with temperature and was therefore determined based on the response of daytime net ecosystem exchange and PAR at different temperatures. Lastly, GPP was estimated by combining the LUE model with the fraction of absorbed photosynthetically active radiation from Sentinel-2 images. The results showed that the LUE model developed for mangrove forests has higher overall accuracy (RMSE = 0.0051, R2 = 0.64) than the terrestrial model (RMSE = 0.0220, R2 = 0.24). The main environmental stressor for the photosynthesis of mangrove forests in China was PAR. The estimated GPP was, in general, in agreement with the in-situ measurement from the two carbon flux towers. Compared to the MODIS GPP product, the derived GPP had higher accuracy, with RMSE improving from 39.09 to 19.05 g C/m2/8 days in 2012, and from 33.76 to 19.51 g C/m2/8 days in 2015. The spatiotemporal distributions of the mangrove GPP revealed that GPP was most strongly controlled by environmental conditions, especially temperature and PAR, as well as the distribution of mangroves. These results demonstrate the potential of the RS-based productivity model for scaling up GPP in mangrove forests, a key to explore the carbon cycle of mangrove ecosystems at national and global scales.

Creating a Life-Support System for Astronauts on a Mission to Mars

The more space science develops, the clearer it is that future generations of our civilization will control, inhabit and travel in space around the Earth. It is hard to imagine that astronauts’ long missions in future will be realized in an only technological environment. Building a life-sustaining system for astronauts on a mission to Mars is our main goal. For the development of an effective life-sustaining unit for use on long space and crewed flights, we need fresh food. The plants, we selected, are radishes (Raphanus sativus) and spirulina (Arthrospira platensis) but it is also necessary to work on the supply of proteins and fats. By calculating the specific nutritional needs of astronauts, we can keep them healthy on long duration space explorations. Water recycling is absolutely necessary. It reduces the load on board the spacecraft. The effect of the physical activity on the oxygen consumption has to be taken into account on spacecraft. For the successful growth of radishes and spirulina, the photosynthetic active radiation supply has to be at least 2μmol/m2/s. In the 2 μmol/m2/s treatment. The most effective influence on both mass and length of cotyledons of radishes, exerted the green and the yellow light. On the other hand, the accumulation of the photosynthetic pigments (chlorophyll A and chlorophyll B) was influenced by the blue and green spectrum of light. The most favourable influence on the accumulation of carotenoids exerted the green and the yellow light. We weighed the mass of spirulina in photosynthetic active radiation 2 μmol/m2/s. According to collected data, the green and the red light were the most favourable for the accumulation of biomass of spirulina. We analysed the concentration of chlorophyll A and chlorophyll B in the biomass. Under the influence of yellow and red lights, chlorophyll A and B were accumulated in a huge amount. The most favourable influence on the accumulation of carotenoids exerted the green and the yellow light.

Effects of Applied Ratio of Nitrogen on the Light Environment in the Canopy and Growth, Development and Yield of Wheat When Intercropped

Changes in the light environment have an important effect on crop growth and yield. To clarify the effects of intercropping and the application of nitrogen on the yield of wheat and light within the crop canopy, the relationship between light and yield and their response to nitrogen fertilizer were studied. In a 2-year field experiment, the characteristics of growth, light, biomass, and yield of wheat were measured using three cropping arrangements (monocropped wheat, monocropped faba beans, and intercropped wheat/faba beans) and four levels of applied nitrogen, in groups termed N0 (0 kg/ha), N1 (90 kg/ha), N2 (180 kg/ha), and N3 (270 kg/ha). The results demonstrated that the application of nitrogen fertilizer increased wheat plant height, spike leaf length and width, and the number of leaves while significantly decreasing wheat canopy light transmittance (LT) and canopy photosynthetic active radiation transmittance (PART), by 7.5–71.1 and 12.7–75.1%, respectively. There was a significantly increased canopy photosynthetic active radiation interception rate (IPAR) of 7.5–97.8% and an increase in biomass of 9.6–38.4%, of which IPAR, biomass, and yield were highest at the N2 level. Compared with monocropping, intercropping increased parameters of wheat growth to varying degrees. Intercropping decreased LT and PART by 10.8–46.4 and 15.7–58.7%, respectively, but increased IPAR by 0.1–66.0%, wheat biomass and yield by 7.5–17.4 and 27.7–47.2%, respectively. The mean yield of intercropped wheat increased by 35.8% over 2 years, while the mean land equivalent ratio (LER) was 1.36, for which a values greater than 1 indicates that wheat and faba bean intercropping is advantageous. Correlation analysis demonstrated that there was a very significant negative correlation between wheat LT and yield, while simultaneously demonstrating a very significant positive correlation between PART and IPAR with yield, indicating that the efficient interception and utilization of light energy in intercropping was the basis for the higher biomass and yield of wheat. In summary, wheat/faba bean intercropping and the application of nitrogen at 180 kg/ha were effective in increasing wheat yield.

THE EFFECT OF PHOTOSYNTHETIC ACTIVE RADIATION ON YIELD AND QUALITY TRAITS IN ‘TOMBUL’ AND ‘PALAZ’ HAZELNUT CULTIVARS

This study was carried out to determine the changes in yield and some quality characteristics of ‘Tombul’ and ‘Palaz’ hazelnut cultivars according to orchards varied in terms of photosynthetic active radiation. The study was carried out in three orchards with full day sun lighted (100% PAR), half day sun lighted (66.34% PAR) and shady (49.93% PAR) in the Fatsa district of Ordu province (Turkey) in 2016. The experiment was designed in random blocks and three replicates. As a results, it was determined that lighting conditions of the orchards have a significant effect on yield and quality traits in both cultivars. As the sun lighting decreased, yield and good kernel rates decreased; blank nut ratio increased. In addition, the oil content was decreased as the lighting in the orchards increased but it was found to be significant only in ‘Tombul’ hazelnut cultivar. As a result, it may be recommended to take into consideration the natural lighting conditions of the orchards in the new plantations, not to plantation the orchard in places that do not have any sunlight and to apply the cultural practices in existing orchards to get enough light.

Boosting Algal Bloom by Five-Fold with AIEgens: Towards the Development of Biofactory

Human population is now faced with grand challenges such as global warming, food shortage and energy sustainability, which could be partially solved by massively increasing the growth and yield of photosynthetic organisms which capture the light energy to convert carbon dioxide and water into usable chemical energy. Cyanobacteria and eukaryotic microalgae are considered as attractive targets to be exploited by the algal factory because of their fast growth, low cost cultivation, less arable land and the diversity of high-value chemical substances produced. Many optical approaches have been introduced to increase the efficiency in artificial culturing systems, such as adding a luminescent layer that absorbs ultraviolet light and emits photosynthetic active radiation for cyanobacteria. In this work, we introduced luminogens with aggregation-induced emission characteristics (AIEgens) into the growth medium of a marine cyanobacteria. These hydrophobic AIEgens formed highly emissive luminogenic aggregates in the aqueous <a>medium and</a> dispersed around the cyanobacteria. Remarkedly, the number of cyanobacteria incubated in the medium with AIE aggregates was 5-fold more than the control group after 14-day culturing. The increased photosynthetic active radiation and the change of cyanobacteria protein expression in photosynthesis and metabolism might be the reason. Our study is the first using organic luminogenic aggregates as optical engineering inside the growth medium to dramatically increase the growth of cyanobacteria and demonstrated that AIEgens is promising technologies in the development of algal factories.

Boosting Algal Bloom by Five-Fold with AIEgens: Towards the Development of Biofactory

Human population is now faced with grand challenges such as global warming, food shortage and energy sustainability, which could be partially solved by massively increasing the growth and yield of photosynthetic organisms which capture the light energy to convert carbon dioxide and water into usable chemical energy. Cyanobacteria and eukaryotic microalgae are considered as attractive targets to be exploited by the algal factory because of their fast growth, low cost cultivation, less arable land and the diversity of high-value chemical substances produced. Many optical approaches have been introduced to increase the efficiency in artificial culturing systems, such as adding a luminescent layer that absorbs ultraviolet light and emits photosynthetic active radiation for cyanobacteria. In this work, we introduced luminogens with aggregation-induced emission characteristics (AIEgens) into the growth medium of a marine cyanobacteria. These hydrophobic AIEgens formed highly emissive luminogenic aggregates in the aqueous <a>medium and</a> dispersed around the cyanobacteria. Remarkedly, the number of cyanobacteria incubated in the medium with AIE aggregates was 5-fold more than the control group after 14-day culturing. The increased photosynthetic active radiation and the change of cyanobacteria protein expression in photosynthesis and metabolism might be the reason. Our study is the first using organic luminogenic aggregates as optical engineering inside the growth medium to dramatically increase the growth of cyanobacteria and demonstrated that AIEgens is promising technologies in the development of algal factories.