Parenchyma and Epidermal Cell Length in Relation to Plant Height and Culm Internode Length in Winter Wheat

1. Parenchyma and epidermal cell lengths and their relationship to culm internode length and plant height were studied in eight varieties of winter wheat (Triticum aestivum L.) grown in a field nursery at Lincoln, Nebraska, in 1954. 2. Both cell types differed significantly in length in the different internodes. Generally close agreement in cell length was observed for the two cell types in corresponding internodes. 3. An inverse relationship was found to exist between lengths of parenchyma cells and of culm internodes. The longest parenchyma cells occurred in the shortest (lowest) internode, and parenchyma cell length was less in each successively higher and longer internode. 4. Epidermal cell length followed somewhat the same pattern as parenchyma cell length but was less consistent. The shortest epidermal cells were always in the peduncle or longest internode, but the longest ones occurred variously in the first, second, or third internodes. 5. Significant varietal differences in cell length were found. The culms of tall varieties usually contained longer cells than short-growing varieties, although a number of exceptions were observed in some individual internodes of the varieties. 6. The numbers of parenchyma and epidermal cells contributing to culm internode length were calculated from the average cell and internode lengths. In all the varieties the numbers of both types of cells increased substantially in the higher and longer internodes of the culms. 7. The estimated total number of parenchyma cells contributing to culm length generally increased with the height of a variety; the relationship of total number of epidermal cells to plant height was less consistent.