Improvement of grain yield (GY) at farm level, which is closely related to GY potential, seems to be the main alternative to increase wheat (Triticum aestivum L) production. The aim of current research was to assess the genetic progress of GY potential and associated physiological traits as well as the GY stability under diverse environments of cultivars released to the Argentine market during the last five decades (1971–2011). Ten cultivars, classified into two groups of five according to the time to anthesis in late cycle (LC) and early cycle cultivars (EC), were grown under twelve environments (E1 to E12) in Pergamino, Argentina. The environmental index of GY (average of cultivar’s GY in each environment) ranged from 174 to 602 g m⁻². Under potential conditions (E1 to E3, 602 to 548 g m⁻²), GY improved at 0.74 % per year of release (YOR) (or 4.20 g m⁻² per YOR) across all cultivars. The harvest index (HI), particularly in LC, and total biomass produced at physiological maturity (BT_PM), associated with crop growth rate during stem elongation (CGR_SE) and total biomass produced at anthesis (BT_A), particularly in EC, were improved by breeding explaining the GY potential increase. Maximum HI reached 0.46, suggesting it can be further improved in both groups, but pre-anthesis growth should continue increasing in EC, as it seemed to be a yield-limiting trait for these cultivars. Grain number per m⁻² (GN) increased by recent breeding in both groups with no change in grain weight (GW). This was a consequence of greater grain number per spike (GNS) in EC, as expected, but higher spike number per m⁻² (SN) in LC. Fruiting efficiency (FE, grains g⁻¹ of spike dry weight at anthesis -SDW_A-), rather than SDW_A, seems to have been improved by recent breeding, turning it a key trait to further increase GN. Finally, modern cultivars out-yielded the old ones in a wide range of environments, suggesting that wide adaptation is a valid breeding strategy for Argentine conditions.

在农场层面提高粮食产量 (GY)，这与 GY 潜力密切相关，似乎是增加小麦 ( Triticum aestivum L ) 产量的主要替代方案。当前研究的目的是评估过去 50 年（1971-2011 年）投放到阿根廷市场的品种在不同环境下 GY 潜力和相关生理性状的遗传进展以及 GY 稳定性。在阿根廷 Pergamino 的 12 种环境（E1 至 E12）下，根据晚周期 (LC) 和早周期品种 (EC) 的开花时间分为两组，每组五个。GY 的环境指数（每个环境中栽培品种 GY 的平均值）范围为 174 至 602 gm ^-2. 在潜在条件下（E1 到E3，602到 548 gm ^-2），所有品种的GY 以每年释放 (YOR) 的 0.74 %（或每个 YOR 4.20 gm ^-2）提高。收获指数 (HI)，特别是在 LC 和生理成熟时产生的总生物量 (BT _PM )，与茎伸长期间的作物生长速率 (CGR _SE ) 和开花时产生的总生物量 (BT _A ) 相关，特别是在 EC 中，通过育种来改善 GY 潜力增加。最大 HI 达到 0.46，表明它可以在两组中进一步提高，但花前生长在 EC 中应继续增加，因为它似乎是这些品种的产量限制性状。每米粒数^-2(GN) 因近期育种而增加，而粒重 (GW) 没有变化。这是 EC 中每穗粒数 (GNS) 较大的结果，正如预期的那样，但LC 中每米^-2 (SN)穗粒数较高。结实效率（FE，开花时穗干重的籽粒 g ^-1 -SDW _A -），而不是 SDW _A，似乎通过最近的育种得到了提高，使其成为进一步增加 GN 的关键性状。最后，现代品种在广泛的环境中产量超过旧品种，这表明广泛适应是阿根廷条件下的有效育种策略。