In the 1st (1981) and 2nd (1982) fruiting years, ‘Benton’ strawberry (Fragaria x ananassa Duch.) formed 25% to 30% more crowns/plant than the advanced breeding selection OR-US 4356. ‘Benton’ had fewer trusses/crown than OR-US 4356 in 1981 (0.93 vs. 1.47) but both had 1.5 in 1982. OR-US 4356 had about 60% more fruit/truss in each season; however, ‘Benton’ had 75% greater mean berry weight than OR-US 4356, so that the 2 genotypes produced essentially the same yields/plant in each season, averaging 0.82 kg (1981) and 0.94 kg (1982). The genotypes did not differ in the total number of achenes/berry. Both showed a linear increase in berry weight with achenes/berry; yet OR-US 4356 had significantly lower berry weight than ‘Benton’ at equivalent achenes/berry. Increased berry expansion in ‘Benton’ was reflected by a reduction in number of achenes/cm2 of berry surface. The values, averaged over both seasons, were 10.6 (‘Benton’) and 14.0 (OR-US 4356). OR-US 4356 failed to produce higher yields than ‘Benton’ because of limitation in fruit expansion.
Field grown strawberry plants (Fragaria × ananassa Duch.) of an advanced breeding selection (OR-US 4681) were harvested every 3–4 days during establishment and through fruiting the next spring. Plant dry weight and leaf area increased rapidly during mid-summer, then slowed and finally ceased in October. Absolute growth rate (AGR) peaked at 1 g dry matter/day near 1 Sept., then fell to zero by early October. Over this period, there was a decrease in weekly mean temperature (37%), solar radiation (47%), and daylength (35%). Maximum values of relative growth rate (RGR) (0.044 g/g/day) and unit leaf rate (ULR) (9 g/m2/day) were determined at the start of sampling at the end of June; both rates declined steadily thereafter. The following April through June, both plant dry weight and leaf area increased exponentially, whereas RGR remained constant at 0.02 g/g/day, and ULR rose from 5.5 to 6.5 g/m2/day. The rate of dry matter accumulation in fruit was exponential, whereas it was linear in leaf lamina and stems (crowns plus petioles). A much smaller proportion of dry matter was partitioned to leaves during fruiting than during plant establishment.