In agricultural experiments where the land requirement is rigid then the actual layout in the field is laborious and approach to the central plots becomes difficult.On the other hand if the number of treatment is small, the degree of freedom associated with experimental error becomes too small for the error to be reliably estimated.
![r asreml latin square r asreml latin square](https://0.academia-photos.com/attachment_thumbnails/49339067/mini_magick20190131-3509-mtez7i.png)
The experiment becomes impractical if the number of treatment is very large because of large number of replications required.
![r asreml latin square r asreml latin square](https://els-jbs-prod-cdn.jbs.elsevierhealth.com/cms/attachment/7a310988-8c06-4c4f-9648-0c43cd1e2178/gr6_lrg.jpg)
Laboratory trials with replication over time, such that the difference among experimental units conducted at the same time and among those conducted over time constitute the two known sources of variability.Greenhouse trials in which the experimental pots are arranged in straight line perpendicular to the glass or screen walls, such that the difference among rows of pots and the distance from the glass wall are expected to be the two major sources of variability among the experimental pots.Insecticide field trials where the insect migration has a predictable direction that is perpendicular to the dominant fertility gradient of the experimental field.Field trials where fertility gradient exists in two directions perpendicular to each other, or has a unidirectional fertility gradient but also has residual effects from previous trials.
![r asreml latin square r asreml latin square](https://1.bp.blogspot.com/-d86bXJ62cJQ/YOKCbSy4MbI/AAAAAAAABGk/nPo8Nhk5ekwfl9ntf8gDZjDHcDL8BseSQCNcBGAsYHQ/w1200-h630-p-k-no-nu/Latin%2BSquare%2BDesign%2BThumbnail.png)
Latin square design can be used in following conditions: