the main objective in sampling is to select a sample from a population in order to estimate some unknown population parameter, usually a total or a mean of some interesting variable. a simple way to take a sample of size n is to let all the possible samples have the same probability of being selected. this is called simple random sampling and then all units have the same probability of being ch...

Extended Abstract Introduction and Objective: Sugar is a tonic that produces a large amount of energy in the diet of the world's population. The position of sugar beet in providing part of the sugar required by human society is not hidden from anyone. Given the needs of society, breeding sugar beet hybrids that is high in quantity and quality is inevitable. In addition to plant genetics and ...

     Salt stress is one of the most important environmental constrains that limited agricultural productivity. Salinity stress is also one of the most important obstacles worldwide that production of tolerant cultivars may reduce its problems. In present study, from five promising alfalfa lines, elite genotypes were selected and individually transplanted into isolated polycross nursery for impr...

In order to assess the effect of salinity on root traits and yield of two wheat cultivars, an experiment was conducted in Agricultural, Medical and Industrial Research School, Nuclear Science and Technology Research Institute, Karaj, Iran, using factorial experiment based on complete randomized design with 3 replications. The first factor included sensitive wheat cv. (Tajan) and tolerant cv. (B...

    Indigenous diploid cotton is cultivated in many areas of country due to the saline soil and water. To study adaptability and seedcotton yield stability of three promising native cotton lines selected from interspecific hybrids of G. herbaceum & G. arboreum including three lines along with two diploid controls were planted in a randomized complete block design in four locations (Kashmar, Nis...

abstract this study was carried out to compare disinfecting effects of nanosilver with other feed disinfectants on layer hen performance, immune system, gastrointestinal microflora and intestinal morphology. total of 90 layers (lsl) were divided into five groups consisting: 1-control, 2- formalin (200 ppm), 3- formaycin (200 ppm), 4- nanosilver in drinking water (7.5 ppm) and 5-nanosilver in f...

flow in natural river bends is a complex and turbulent phenomenon which affects the scour and sedimentations and causes an irregular bed topography on the bed. for the reason, the flow hydralics and the parameters which affect the flow to be studied and understand. in this study the effect of bed and wall roughness using the software fluent discussed in a sharp 90-degree flume bend with 40.3cm ...