Abstract No. Oral–40
NEW COTTON GERMOPLASM WITH INTERMEDIATE CYCLE CALLED SP 48114
DEVELOPED BY NATIONAL INSTITUTE OF AGRICULTURAL TECHNOLOGY–INTA
M.A. Tcach, J. Poisson, I. Bonacic, S. Ibalo, A. Montenegro, D. Ojeda and M. Cracogna
National of Institute of Agricultural Tecnology (INTA), Argentina
Cotton in Chaco, Argentina, is cultivated under rainfed conditions. The availability of water during
flowering determines the retention of fruiting structures. Better performance depends mainly on water
stress during the reproductive phase. In varieties with short cycle, the losses caused by stress are the
most important, this necessitates developing varieties with intermediate cycle in order to compensate
losses due to stress during flowering. The objective of this investigation was to select a cotton line with
intermediate cycle and agronomic traits equivalent to early maturing materials. The cross between lines
SP 99138 x SP 99035, was obtained in the 1994 /1995 season. Plants in F2 populations were selected by
visual observation. An individual plant selection SP48114 was obtained. In the period 2004 /2005 the
elite line was a part of a network regional comparative trials conducted at 4 locations for 3 seasons. The
F3 generation was tested for ginning outturn and the progenies were artificial infected with Xanthomonas
axonopodis pv malvacearum, discarding all susceptible plants in short generations. The F8 generation was
tested for the blue disease, caused by cotton leaf roll dwarf virus (CLRDV), by artificial inoculation and
selecting only resistance line. The germplasm SP 48114 is characterized by greater differentiation of
fruiting points on the main stem 5% more than Guazuncho 3 INTA. This commercial variety had short
cycle and high boll retentions in first fruiting branches. The selected line SP 48114 maintains boll
retention in the inferior part of the plant similar to Guazuncho 3 INTA, but continued the process of
flowering for more days. This feature increases the cycle for about 10 days which improves the
compensation at time of water stress. The fiber length was 29 mm and strength 31 g /tex, with lint
percentage about 39 to 40.
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World Cotton Research Conference on Technologies for Prosperity