Some notes on planning plant protection research in block designs with nested rows and columns

Factorial experiments in block designs with nested rows and columns are described with suggestions about how they should be planned. In such experiments the importance of interaction and hidden replication are emphasized. Such experiments are carried out on heterogeneous experimental material. Thus, it is reasonable to seek a design that can withstand the loss of observations. The robustness of a block design with nested rows and columns against the loss of whole blocks is presented, along with examples of such designs.