Relationship between Fiber‐Length Increase and Seed‐Volume Increase in Cotton (Gossypium hirsutum L.)¹

Three cultivars of Gossypium hirsutum L. were chosen for wide differences in fiber length and seed volume: ‘Stoneville 213,’ ‘Paymaster 54B,’ and ‘Acala 1517‐D.’ Increases in fiber length and seed volume were measured from boll ages of 8 to 17 days. During this period the relationship of fiber length to seed volume in each cultivar fit the model L = βV α with R 2 = 0.99, where L = fiber length, V = seed volume, and α and β are the growth parameters. The α value in each was near 0.5, indicating tbat seed volume was increasing as the square of fiber length. This relationship suggests that biological partitioning of available resources within the cotton plant controls some agronomically important parameters.