How strawberry plants cope with limited phosphorus supply: Nursery‐crop formation and phosphorus and nitrogen uptake dynamics

Healthy, well‐rooted planting stocks are important for profitable fruit production of strawberry ( Fragaria × ananassa Duch.). Adequate nutrient inputs and crop‐rotation practices are among the most important measures to insure a successful, rapid development of strawberry nursery plants. However, relationships between macronutrient use and strawberry‐nursery‐plant formation in different rotation environments are not well understood. Our objectives were to assess strawberry plant P : N nutrition and nursery development under various limited and unlimited P inputs applied at different growth stages and to examine how nursery plants cope with limited P inputs. The field studies were conducted in a wheat–ryegrass–ryegrass–strawberry (WRRS) system in 2008 and in another corn–ryegrass–ryegrass–strawberry (CRRS) system in 2009 in Nova Scotia, Canada. The nursery crop was cv. Strawberry Festival and the experimental treatments consisted of three mother‐stock P (MSP) rates (0, 6.6, and13.2 P kg ha –1 ) and five daughter‐plant P (DPP) rates (0, 13.2, 26.4, 39.6, and 52.8 kg P ha –1 ), representing 0%–125% of the regional recommendations for strawberry nursery. The P treatments were arranged with three blocks in a split‐plot design in each field. The results showed that the effects and interactions of the MSP and DPP treatments were significant ( P < 5%) on whole‐plant P and N acquisition and nursery productivity. Two‐year whole‐plant total P and N acquisition varied between (13.2 ± 2.0) kg P ha –1 and (46 ± 7.3) kg N ha –1 (n = 270) in both nursery systems. There was a quadratic regression relationship between nursery runners and daughter plants with plant P and N acquisition (0.33 < R 2 < 0.42, P < 5%). Soil pH levels declined with time and were positively correlated with nursery‐plant formation. Too many runners (18–22 per mother stock) might reduce nursery‐plant formation. Limited P inputs (37.5%–62.5% of regular recommendation) might result in a suitable plant P : N ratio (0.12–0.13) and adequate daughter plant‐to‐runner ratios (1.4–1.7) for optimum nursery formation (14–16 daughter plants per mother stock). Nutrient P was the single controlled factor influencing the N acquisition of nursery plants. High P inputs (> 39.6 P ha –1 or > 75% of regular recommendation) may harm the crops. Therefore, this study implies that low‐input horticulture can improve the nutrition management of strawberry nursery.