فهرست مطالب majid moradkhani

Waste stabilization pond (WSP) is a conventional and widely applicable wastewater treatment unit globally. This system does not require complicated mechanical operating systems but it should not be classified as a simple process at all. Facultative ponds (FP) are the heart of this system as they use the natural symbiosis of facultative bacteria and algae for organic removal. The performance of FP is very reliant on different parameters such as wastewater influent characteristics or environmental operating conditions. Nonetheless, they are simply designed and operated based on parameters like surface organic loads and hydraulic retention time (Khosravi et al. 2013). Some literatures have recently focused on the optimization of WSP layout for higher performance (Shahsavani et al. 2019; Decostere et al. 2017; Espinosa et al. 2017). For example, a question is that which form of FPs, in series or parallel, have the highest performance or operational reliability? Answering to this question is practically a challenge. There is little chance in full scale to compare the performance of FPs with the layouts in series and parallel for long term, with same source of real wastewater, similar climate and operating conditions. This research primarily evaluates and compares the performance of FPs (2008-2020) in series and parallel layout in Delijan WSP.

The aim of present study was to determine the relationship between grain yield and important agricultural characteristics for six lines of rice and Shiroodi cultivar as control in rice research station (Tonekabon) in west of Mazandaran Province in 2015. The experiment was conducted in a randomized complete block design with three replicates. Analysis of variance showed that there was a significant difference between genotypes for all studied traits except flag leaf width, which indicates the appropriate variation among the studied genotypes. Results of mean comparison test showed that the highest and the lowest grain yield were belong to line No. 5 (7831.7 kg.ha-1) and No. 204 (6884.3 kg.ha-1) respectively. Results showed that there were positive and significant correlation between grain yield and number of tiller, 1000-grain weight, filled grain number and number of total grains per panicle. Using stepwise regression method showed that 1000-grain weight, filled grain number and number a tillers had the maximum effect on grain yield. Results of path analysis showed that 1000-grain weight an important and effective trait can be used for selection of high yielding rice lines in breeding programs.

In order to investigate the relationship between morphological properties and choose suitable criteria for improving this research yield on ten new breeding lines and varieties of rice (control) modified rice cultivation area (Shiroodi cultivar) in the crop during 2010 in Tonekabon Rice Research Station in a randomized complete block design with four replications. The results showed that rice genotypes for all traits studied there was a significant difference in the level of one percent. Shiroodi cultivars yield and lines 1 and 2 produced the highest grain than others. Grain yield with fertile tiller number per plant and 100-grain weight was positive correlation and significant was respectively 0.66 and 0.71. The grain yield with plant length at 45 days after seedling, the tiller number, fertile till number per plant and non-fertile tiller number, flag leaf length and flag leaf width, area flag leaf, grain length, grain width, and number of grains per panicle positive correlation non-significant and with plant height treat in maturity and leaf length to width ratio, ratio of grain length to width, panicle length and distance last node non-significant negative correlation. Stepwise regression analysis results showed that the trait of 100-grain weight and a number of fertile tillers per plant had the greatest effect on grain yield increase. Path analysis result revealed that 100-grain weight can grain yield replaced in the selection for grain yield increased.

Due to the high labor costs in the production of rice, use of rice planting and mechanization is one of the basic strategies for sustainability and preparing healthy and strong seedling, transplanting and reducing the cost of rice production. Crop response to mechanized planting with planting machines due to differences in the density and type of planting is different. Therefore, this study aimed to achieve the most suitable criteria on for transplanting age of four varieties of rice. Experiments were conducted in the year of 2009 was conducted at the Chaparsar Rice Research Station (Tonekabon city). crop, using a split-plot design in a randomized complete block design with three replications. The main factor included four levels of transplanting ages (20, 27, 33 and 40 days) and the subplots were four varieties of rice cultivars (Hashemei, Khazar, Hybrid and Shiroodi). Analysis of variance showed that transplanting age affected most of the factors and data shows significant differences at the level of 5, 1 and 0.1 percent. Effects of rice varieties also were significant on all factors. Correlation coefficient of data was positive and showed significant relationship with the parameters. The highest yield was achieved for 20 days rice transplanting age with the amount of 5166.9 kg per hectare. Among cultivars, the highest yield belonged to the Shiroodi verities with 5899.9 kg per hectare. Therefore, to achieve the highest yield potential of shiroodi verities, the 20 day transplanting ages is recommended for planting the rice transplanting by walking type transplanters.