Introduction Different aspects of light including intensity, quality (Spectra), and duration (photoperiod) can influence plant growth and development. The growth and development of ornamental plants are also influenced by light intensity and quality. Energy saving in greenhouse production has received much attention lately. One reason for the interest in utilizing light quality to modulate plant growth and morphology is the recent development of light-emitting diodes (LEDs) as a lighting source in greenhouse production. Such small diodes can easily be placed close to the canopy and can be used to apply a narrow-band light spectrum to the plants. Specific requirements for light Spectral distribution for specific processes like morphogenesis, photosynthesis, chlorophyll and anthocyanin synthesis have been determined in different species. The aim of the current study was to investigate the biophysical properties of chlorophyll fluorescence of Hypoestes phyllostachya plants in response to different light Spectra.Materials and Methods Research experiments were conducted on Hypoestes phyllostachya in a completely randomized design with six treatments of different light quality and three replications. The seeds were planted in plugs and in a mixture of 70% peat moss and 30% perlite. Seedlings were grown in natural greenhouse (control) and LED (100% Blue, 15% Blue +85% Red, 30% Blue +70% Red, 15% Blue +65% Red + 20% White and 30% Blue +50% Red + 20% White). Since the main goal of the study was to compare the effect of LED light quality with sunlight in conventional greenhouse conditions. The LED treatments were applied from fourth month old seedlings until five weeks in a growth chamber with the light/dark regime of 15/9 hours, 23±5°C temperature, and 65±5% relative humidity. While, their pots in the greenhouse with 55±5 mol.m-2.d-1 DLI, 21±5°C average daily temperature and 65±5% relative humidity (Data logger 8808 temp. + RH) were regarded as the control treatment. After five weeks, the fluorescence chlorophyll was measured.Selected leaves were dark-adapted prior to the measurements and OJIP protocol was applied using a fluorometer (FluorPen FP 100-MAX, photon system instruments, Drasov, Czech Republic). The fluorescence measurement was performed using a saturating. FluorPen software was used to extract data from the original measurement. Data extracted were used to analyze the following data according to the equations of the JIP test: fluorescence intensities at 50 μs (F 50 μs, considered as the F0), 2 ms (J-step denoted as FJ), 60 ms (I-step, FI), and maximum fluorescence intensity (FM, FP). The JIP-test was used to quantify the amount of energy that flow via the PSII. Performance index was measured on the absorption basis (PIABS, a multi-parametric expression). Probability that a trapped exaction promote an electron in electron transport chain (ETC) beyond the primary acceptor Quinone (QA−), maximum quantum efficiency of PSII (FV/FM), specific energy fluxes per reaction center (RC) for energy absorption (ABS/RC), trapped energy flux (TR0/RC), electron transport flux (ET0/RC) and dissipated energy flux (DI0/RC) were calculated according. Finally, the data were statistically analyzed with SAS (9.4) software package, and the means were compared by LSD test at p < 0.05 level.  Results and Discussion Fast Chl fluorescence induction curves (OJIP) was the main parameters used for the screening of different light treatments. OJIP test is shown to be a proxy to detect PSII bioenergetics and indicates changes in the status and function of PSII reaction centers, antenna, as well as in donor and acceptor sides of PSII. The maximum quantum Yield of PSII (FV/FM) and relative maximal variable fluorescence (Fm/F0), significantly increased in 15% Blue +85% Red, 30% Blue +70% Red, 15% Blue +65% Red + 20% White. PIABS, one of the OIJP test parameters that provide valuable awareness about photosynthtic performance, considerably decreased under control and 30% Blue +50% Red + 20% White treatment. Unlike PIABS, ET0/RC did not show a significant difference under different treatments. The specific energy fluxes per RC for energy absorption (ABS/RC) significantly increased under control and 30% Blue +50% Red + 20% White treatment. TR0/RC increased in plants under control and 30% Blue +50% Red + 20% White treatment. Treated plants under 15% Blue +85% Red and 30% Blue +70% Red showed the lowest in dissipated energy flux (DI0/RC).  During an ideal condition without any additional stress, the total PSII pool can be completely inactivate and retrieve without a detectable photoinhibition.Conclusion When plants exposed to 100% Blue and 30% Blue +50% Red + 20% White treatments as well as in control plants, FM/F0, FV/FM and PIABS significantly decreased.  Also ABS/RC, TR0/RC and DI0/RC, significantly increased.

In order to investigate the possibility of quinoa producing in Garmsar, Iran, a factorial experiment conducted in randomized complete block design with three replications in 2018-2019 growing season at Garmsar Agricultural Research Station. The factors were planting date at three levels (March 6th, April 1st and April 6th) and the three genotypes of quinoa (Q26, Q29 and Titicaca). Results showed that the effect of planting date was significant for all studied traits except the harvest index. Also, all studied traits were significantly different in all genotypes. Titicaca planted on March 6th had the highest Yield (2276 kg.ha-1).The grain Yield and Yield components decreased with the delaying the planting date. Compared to early plantings, Latest date, April 6th, led to reduction of all traits, especially grain Yield (about 50%). The results of simple phenotypic correlation between the studied traits showed that grain Yield per hectare had the highest correlation with plant Yield (0.877) and then with leaf area index (0.832), panicle weight (0.815) and number of branches per plant (0.745) that was significant at the 1% probability level.

Performance-Based Plastic Design (PBPD) method has been recently developed to achieve the enhanced response of structures to earthquake. To reach this goal, several ways have been suggested. In this paper, the schemes of calculating base shear in the (PBPD) procedure will be studied. Two techniques of determining base shear will be used. The base shear of two steel moment frames will be found by these two processes. By using the difference between the input energy and the elastic strain energy to obtain the plastic energy, the plastic design is then performed to detail the frame members in order to achieve the intended Yield mechanism and behavior. The inelastic seismic behaviors of the four frames were studied through nonlinear static and dynamic analyses. These two suggested techniques and their comparisons have not been proposed yet. This kind of plastic design has three main parts. Calculating base shear is the first and important portion. The second part consists of the member plastic design for flexible behavior. To design elastic members by using column trees is the third and last part. Throughout this study is devoted to present two methods for calculating base shear. The moment frames will be investigated in this article.

Identifying the constraining factors of production and Yield gap is very important. Therefore; this research was performed to identify the production constraining factors of local rice cultivars. All management practices from nursery preparation to harvesting stages for 100 paddy fields of local rice cultivars were recorded through field studies, in Sari, from 2015-2016. In the CPA, the actual and calculated potential Yield were 4495 and 5703 kg/ha, respectively and the gap was 1221 kg/ha. The Yield gap caused by number of top-dressing variables was 324 kg/ha, equal to 27% of the total Yield gap. The Yield gap related to previous year of legumes cultivation was 218 kg ha-1, equal to 18% of the total Yield variation. Among the 10 variables entered in the CPA model, the effects of top-dress fertilizer application and its application frequency and foliar application were remarkable, which could compensate a significant part of the Yield gap (444 kg/ha, 37% of total) in the farmers’ fields by managing these variables. According to boundary line analysis (BLA) finding, actual Yield mean on the basis of optimal limit related to 12 variables under study was 5369 kg/ha, with 881 kg/ha Yield gap . Mean relative Yield and relative Yield gap for 12 variables (transplanting date, seedling age, number of seedlings per hill, planting density, nitrogen and phosphorous per hectare, nitrogen before transplanting, harvesting date, lodging problem, pest problem, diseases problem and weeds problem) were 83.64 and 16.35 kg/ha, respectively. Based on the finding, it can be stated that the model precision is appropriate and can be applied for both estimation of the quantity of Yield gap and determining the portion of each restricting Yield variables.

Purpose: The use of supplementary light in regions with low natural sunlight is necessary to fulfill the increasing consumer requests for fresh vegetables. This study aimed to investigate the effect of different combinations of red and blue LEDs on Yield and quality of greenhouse-grown sweet pepper (Capsicum annuum L.) fruits during the growth period. Research method: The experiments were conducted in Rasht, Iran as split plots in the form of a completely randomized design in three repetitions (four plants per plot) on two cultivars of sweet pepper (Padra and Shadlin). With the appearance of the first flower buds, plants were exposed to different light treatments including: three combinations of red (R) and blue (B) LEDs (T1:R8B1, T2:R7B2, and T3:R6B3), with a same intensity of 200 μmolm-2s-1 as supplement light to the natural light, together with natural light as control treatment (CT). Sweet pepper fruits were harvested weekly over 27 weeks and fruit Yield and quality were assessed. Findings: Supplemental light using LEDs significantly increased Yield and fruit quality parameters (except titratable acidity and maturity index) compared to the control. Marketable Yield was differed among the light treatments and plants exposed to T3 showed the highest marketable Yield (14.58 kg/m2). The effect of supplemental light on total Yield was more detectable when the average daily light integral was the lowest (for example, the difference between T3 and the control treatment in January was 1.27 kg/m2, while this difference was 0.68 kg/m2 in June). No significant difference was observed between cultivars and T3 was the best treatment in most parameters. Research limitations: No limitations were found. Originality/Value: In the northern regions of Iran, even in the months that do not seem to have light limitations, the use of supplementary light is recommended to increase the Yield of sweet peppers in the greenhouse.

In order to investigate the effect of different light Spectra on growth and photosynthetic properties of four cultivars (‘Red’, ‘Black Dragon’, ‘Velvet Red’ and ‘Improd’) of coleus, in six growth chambers equipped with normal greenhouse light (control), 100 % blue light, 15 % blue light+85 %red light, 30 % blue light+ 70 % red light, 15 % Blue light+65 % red light+20 % white light and 30 % blue light+50 % red light+20 % white light, a factorial experiment as a completely randomized design was done. After five weeks of exposure of plants to different lights, photosynthetic biophysical parameters and plant growth characteristics were investigated. The maximum quantum Yield of PSII (FV/FM) and relative maximal variable fluorescence (Fm/F0), significantly increased in combined treatments of 30 % blue+70 % red (‘Red’), control (cultivars ‘Black Dragon’and ‘Velvet Red’) and a combination of 30 % blue+50 % red+20 % white (‘Improd’ cultivar) was obtained. The specific energy fluxes per reaction center for energy absorption (ABS/RC) significantly increased in ‘Improd’ cultivar with 100 %blue light, a combination of 15% blue+65% red+20 % white and control treatments. Since PIABS can be used as an indicator of PSII life, the results of the present study indicate that the control treatments (‘Velvet Red’), 30% blue+70 % red (‘Red’), 30 % blue+50 % red+20 % white (‘Black Dragon’ and ‘Improd’) were suitable treatments to support the natural function of photosynthesis.

Two accurate, rapid, sensitive, inexpensive, and eco-friendly spectrophotometric techniques have been validated for simultaneous determination of chlorhexidine and triclosan. The first method (Q- Absorbance Ratio Spectra method, was applied at 272.89 nm (isoabsorptive Point) and 259.00 nm (λ-max of chlorhexidine) with 282.00 nm (λmax of triclosan). The final concentrations for chlorhexidine and triclosan were computed using the Q-equations. The linearity ranges were 1.0-20.0 µg/mL and 1.0–50.0 µg/mL, respectively. The second method, “H-Point standard addition method,” was applied at pair of wavelengths (251.00 and 271.00) nm and (272.00 and 283.00) nm, respectively. The linearity range for both methods is 4.0–40.0 µg/mL. The recovered values ranged from 96.94-100.09% to 96.38-99.76%. The statistical comparisons of the accuracy and precision of the outputs from the suggested methods were compared using, Student's t-test, F-test, and One-way ANOVA. The proposed methods were successfully applied for the determination of chlorhexidine and triclosan in various toothpaste samples. Lastly, an assessment of the environmental impact of the proposed techniques was conducted utilizing the green analytical procedure index and analytical eco-scale approaches as a measure of the "greenness" profile.