Identification of phenological stages is the first step to study the plant response to environmental changes, such as climate, temperature, precipitation, fertilization, irrigation and biological control. In order to identify the phenological stages, 100 seedlings were studied at 5-10 days intervals. Stem and leaf length growth were measured by ruler and caliper to draw growth rate curve. Results showed that annual, biennial and 3-years old and older up to productive age of Pinus sylvestris were classified into 10, 10, 9 and 8 groups, respectively. Time of phenological stages was slightly different between biennial and older seedlings. Sigmoidal growth curve of biennial seedlings revealed that the effect of middle part of last year stem on increased seedling height was more than upper part (apical meristem). Hence any parameter that increases middle part of annual seedling will consequently increase the length growth of biennial seedlings. Stem elongation was affected by phenological stage of lammas shoot at the late growth season. Appearance of leaf buds coincides maximum length growth of seedling stem and young trees.

To investigate the response of corn to combined application of chemical fertilizers with rhizobacteria plant growth promoting, an experiment was conducted in 2017 at Research farm of Agricultural and Natural Resources Campus of Tehran University, Karaj, Iran, in a randomized complete block design with four replications. Four nutritional treatments including T1 (Control treatment without applying fertilizer), T2 (Just PGPRs), T3 (Use chemical fertilizers based on soil test) and T4 (T3 + PGPRs) were considered. According to the results, the highest total dry weight (3.9 kg/m2), crop growth rate (79.8 g.m-2.day-1), net assimilation rate (15.3 g.m-2.day-1) and grain yield (18.2 ton.ha-1) were observed in T4 treatment and T2 treatment produced the highest  leaf area index (5.3), leaf area duration (205.2) and specific leaf weight (78.5 g.m-2) . Also, the lowest value of all traits was observed in in T1 (control) treatment. The results showed that the presence of rhizobacteria plant growth promotioninduction in the corn nutrition program increased the growth and growth indices of the plant. Combined application of chemical fertilizers with rhizobacteria plant growth promoting resulted in the highest growth and final grain yield of corn.

Stevia rebaudiana Bert. is a medicinal plant, mostly utilized as a suitable sweeter for diabetic patients. In this research, the effect of single or co-inoculation of Arbuscular Mycorrhiza Fungi (AMF) and bacteria (Bacillus polymixa, Pesudomonas putida and Azotobacter chroococcuom) on regenerated plantlets in tissue culture was investigated in intervals of 15, 30, 45, 60 days after planting. Results showed that in comparison to control, inoculation with single and triple treatments significantly increased length, fresh and dry weight of aerial parts and stevioside content until 60 days after planting while the best enhancement was observed in dual inoculations especially in Glomus+Azotobacter treatments. Interestingly, in dual or triple inoculations, maximum relative growth rate was obtained in 15-30 days and reduced in 30-45 days after planting that was in accordance with their flowering time but in single inoculation maximum relative growth rate was available in 30-45 days and with promoting of flowering phase in 45-60 days declined severely. However, maximum stevioside accumulation rate was obtained 30-45 days after planting in all treatments and in 45-60 days after planting reduced severely in single or triple inoculations and more slightly in dual inoculations. Therefore, microorganisms affect relative growth rate, phenology and stevioside accumulation pattern in stevia.

In order to investigation of the effect of pH and its application time on growth and biological nitrogen fixation (BNF) in subterranean clover, a factorial experiment was carried out using a completely randomized design with 3 replications in hydroponis culture. The treatments were three pH rates (5.5, 7.0 and 8.5) and their application times (before and after in inoculation). Seedlings, after 50 days growth, were measured for number and fresh weight of nodules, leaf area, root shoot and total dry weight, and nitrogen content of and shoot (using miro- kjeldal method). Results showed that pH application before inoculation had more negative effect on measured characteristics that its application after inoculation. Nodule fresh weight was 12.6 % lower when pH treatment was applied before inoculation. The lower leaf area, root and ahoot dry weight and root nitrogen content were observed in pH=8.5 applied before inoculation. At pH=7.0 all measured traits were maximum and the minimum amounts were measured in pH=8.5. the best growth and BNF were observed at pH=7.0  

Introduction: In infectious diseases, there are essential indices used to describe the disease state. In this study, we estimated the basic reproduction number, R0, peak level, doubling time, and daily growth rate of COVID-19. Methods: This ecological study was conducted in 5 provinces of Iran. The daily numbers of new COVID-19 cases from January 17 to February 8, 2020 were used to determine the basic reproduction number (R0), peak date, doubling time, and daily growth rates in all five provinces. A sensitivity analysis was conducted to estimate epidemiological parameters. Result: The highest and lowest number of deaths were observed in Hamedan (657 deaths) and Chaharmahal and Bakhtiari (54 deaths) provinces, respectively. The doubling time of confirmed cases in Kermanshah and Hamedan ranged widely from 18. 59 days (95% confidence interval (CI): 17. 38, 20) to 76. 66 days (95% CI: 56. 36, 119. 78). In addition, the highest daily growth rates of confirmed cases were observed in Kermanshah (0. 037, 95% CI: 0. 034, 0. 039) and Sistan and Baluchestan (0. 032, 95% CI: 0. 030, 0. 034) provinces. Conclusion: In light of our findings, it is imperative to tailor containment strategies to the unique epidemiological profiles of each region in order to effectively mitigate the spread and impact of COVID-19. The wide variation in doubling times underscores the importance of flexibility in public health responses. By adapting measures to local conditions, we can better address the evolving dynamics of the pandemic and safeguard the well-being of communities.

To evaluate the effect of time and rates of imazethapyr application on weed control of bean field an experiment was conducted in Agricultural Research Station of Lorestan University based on the randomized complete block design (RCBD) with three replications in 2015-2016. In this experiment, the effects of pre planting, pre emergence and post emergence applications of imazethapyr with different rates (0. 25, 0. 5, 0. 75 and 1 lit. ha-1) and pre planting imazethapyr mixed with soil (1 lit. ha-1) plus post emergence with weed control in two levels (control and non-control) was studied. The most important weed species in the experimental site were safflower (Carthamus oxyacantha), catchweed bedstraw (Galium tricornutum), wild mustard (Sinapis arvensis), cow cockle (Vaccaria grandiflora), chickweed (Conringia orientalis). Weed density in weedy control condition was estimated to be 133 plants. m-2. The results showed the maximum percentage of weed dry weight loss, as compared to not controlling weed due to imazetapir post-treatment application of 0. 75 and 1 L. ha-1, was 86. 95%. Also highest average root length (12. 46 cm), root dry weight (95 g), number of branches (5. 33), number of seeds per pod (9. 3) and seed yield were observed in hand weeding. The highest plant height (88. 33 cm) belonged to weed control treatment, the highest LAI (2. 59) in herbicide usage, in pre planting (0. 25 lit. ha-1), the highest average number of pod per plant (10 pod), number of pod per m-2 (100 pod) and biological yield (33367. 1 kg. ha-1) resulted from pre emergence herbicide application (0. 5 lit. ha-1). The highest of 100 seed weight (109. 6 g) for pre planting herbicide application (1 lit. ha-1) plus herbicide post emergence application (1 lit. ha-1) was seen. The results also showed that, after hand weeding, the best concentration of imazethapyr pre emergence application (0. 5 lit. ha-1) that it could decrease weed density by 99% as compared to not controlling weed. This treatment (imazethapyr pre emergence application (0. 5 lit. ha-1) was the best treatment. Higher concentrations of herbicides also decreased bean yield because of burning, reduction in leaf area and photosynthesis.

In this paper, an economic order quantity (EOQ) inventory model for a deteriorating item is developed with the following characteristics: (i) The demand rate is deterministic and two-staged, i.e., it is constant in first part of the cycle and linear function of time in the second part.(ii) Deterioration rate is time-proportional.(iii) Shortages are not allowed to occur.The optimal cycle time and the optimal order quantity have been derived by minimizing the total average cost. A simple solution procedure is provided to illustrate the proposed model. The article concludes with a numerical example and sensitivity analysis of various parameters as illustrations of the theoretical results.

To obtain detailed information of sowing density and defoliation intensity under more controlled conditions on herbage production and seed yield, Paraggio medic was grown on raised-beds located outdoors at the Waite Agricultural Research Institute. A split randomized block design was used. Treatments comprised three sowing rates (densities): Low (3 kg/ha), Medium (15 kg/ha) and High (75 kg/ha) (based on pure germinating seed which gave 75, 375 and 1875 seedlings/m2 respectively); four defoliation intensities: Control (undefoliated), Low (6 cm from ground level), Medium (4 cm) and High (2 cm) to simulate different grazing pressures and two defoliation systems of continuous (defoliation from June 1) and deferred (defoliation from June 29). The total combination for experimental blocks was: Main plots, defoliation systems (2) x Sub plots. Sowing densities (3) x Sub-sub plots defoliation intensities (4) x Blocks (4) = 96 micro plots. The continuous defoliation system produced significantly higher (P<0.05) available forage as well as total pasture production (P<0.05) than the deferred. High sowing rate increased (P<0.01) forage availability and total pasture production. Medium and high defoliation intensities significantly (P<0.01) reduced available forage and total pasture production in the deferred defoliation system. Seed production was adversely affected by defoliation intensity.