RELATIONSHIP BETWEEN APEX DEVELOPMENTAL STAGE, TILLER DENSITY AND YIELD IN DURUM WHEAT (Triticum durum Desf.)

• Published in: Cereal research communications 1998-01, Vol.26 (2), p.177-182
• Main Authors: Möckel, F.E., Cantanutto, M.A, Gallez, L.M., Miravalles, M.T.
• Format: Article
• Language: English
• Subjects: Breeding; Crop management; Developmental stages; Durum wheat; Grains; Pampas; Plant dietary protein; Plants; Tillering; Tillers; Wheat
• ISSN: 0133-3720; 1788-9170
• DOI: 10.1007/bf03543485

In the semiarid Pampas of Argentina, durum wheat yields are highly dependent on rain distribution and N availability, and consequently very variable. The aim of this study was to determine if simple phenotypic parameters, evaluated at the spike differentiation stage, which in term are influenced by prevailing environmental conditions, can be used to predict grain and protein yield, with a certain precision at an early enough stage of the crop cycle to allow interventive decisions. In order to assess the influence of the developmental stage of the main stem apex (APEX), the number of tillers per square meter (TILL) and the dry matter production (DMW), upon grain yield, thirteen trials were conducted in the Semiarid Pampas over two years, with two durum wheat cultivars (Buck Cristal and Buck Candisur), two fertilization treatments: unfertilized (YUNF) and 138 kg N ha− (YFER) at the end of tillering. Multiple linear regression analysis was performed. Kernel weight, protein content and protein production per unit area were also regressed with APEX, TILL and DMW. For each model variables were selected with the "forward" selection STEPWISE procedure in the SMDP New System computer program package. In the best model, APEX and TILL significantly predicted grain yield of unfertilized plots at the spike differentiation period (R2 = 0.596; p≤ 0.01). These variables also correlated significantly with kernel weight and protein production, although these results must be considered as preliminary ones.