RESUMEN
In the last century, more than a hundred of cultivars were used in the cotton production system in Colombia. Breeding for cultivars adapted to tropical environments had been the main purpose of the Colombian agricultural research institutions dedicated to cotton. Data describing yield and fiber quality traits of these cultivars (and the introduced ones mainly from USA) is scattered across grey literature which reduces chances of discovering, accessing and assessing this information.This data article contains databases describing i) Colombian and introduced Upland cotton cultivars used in Colombia and ii) ramulosis-resistance scores of lines developed by the Colombian breeding program. The first database was constructed from data extracted from grey literature mainly produced by ICA and CORPOICA (rebranded today as AGROSAVIA), the Colombian agricultural research agencies. The second one describes the Cereté lines (LCER) database. These advanced breeding lines were developed for improved yield performance in tropical environments, specifically monsoon and savanna climates. The LCER dataset also describes the ramulosis field resistance of these cultivars. Ramulosis is an endemic disease in South America caused by Colletotrichum gossypii var. cephalosporioides. The data in this article supports and augments information presented in the research articles [1]: and [3].