Phenology Measurements and Fiber Associations of Near‐Long Staple Upland Cotton

Breeding for long staple, early maturing upland cotton ( Gossypium hirsutum L.) genotypes is a criterion for many breeding programs. Vertical flowering interval, horizontal flowering interval, and boll maturation period of long staple cotton was studied in four field‐grown experimental strains and three cultivars in 1998 and 1999 at College Station, TX. Phenological traits of earliness, fiber length development period (FLDP), and fiber quality characteristics, especially fiber length measurements, were evaluated. TAM 94L‐25 and TAM 94M‐14, near long staple breeding lines, exhibited agronomically acceptable vertical (VFI) and horizontal (HFI) fruiting intervals and a slightly longer boll maturation period (BMP) when compared with current and obsolete cultivars. Fruiting interval measurements, BMP, and FLDP were all positively associated. No associations among fiber length measurements and earliness components were noted. Positive correlations were detected between FLDP and advanced fiber information system (AFIS) upper quartile length of fibers by weight (UQLw) and high volume instrument (HVI) upper half mean fiber length (UHM) across these seven genotypes. Negative relationships were noted between BMP and fiber quality parameters, while FLDP was negatively associated with fiber maturity parameters. Breeding for long staple genotypes has been successful, resulting in lines that possess improved yield and fiber quality but without unduly delaying crop maturity.