Understandingcharacteristics of nutrient uptake and accumulation in plants would be highly significant in the realization of high-yielding and high efficiency of resource use in rice and wheat. This study aimed at investigating uptake and accumulation characteristics of nitrogen (N), phosphorous (P), and potassium (K) in rice and wheat plants under super-high-yielding cultivation in the wheat-rice planting system in the lower reaches of Yangtze River of China. Two high-yielding wheat varieties and two rice varieties were field-grown for two years. Two cultivation patterns, the local farmers’ practice and super-high-yielding cultivation, were used. The super-high-yielding cultivation adopted two new key techniques, i.e., site-specific nitrogen management and alternate wetting and moderate drying irrigation in rice and controlled soil drying irrigation in wheat. In comparison with those under the local farmers’ practice (wheat yield < 8 t ha-1 and rice yield < 9 t ha-1), the total uptake of N, P, or K in plants was significantly increased, and the accumulation of N, P, or K was significantly decreased before stem elongation, whereas it was significantly increased in the durations from the stem elongation to flowering and from flowering to maturity under the super-high-yielding cultivation (wheat yield > 9 t ha-1 and rice yield > 12 t ha-1). The total uptake of N, P, and K under the super-high-yielding cultivation was 265, 58, and 256 kg ha-1 for wheat and 256, 79, and 321 kg ha-1 for rice, respectively. The proportion of N, P, or K accumulated in plants during the mid and late growth period (from stem elongation to maturity) to the total uptake of nutrients was 50–60% for wheat and 60–70% for rice. The super-high-yielding cultivation significantly increased partial factor productivity of N, P, or K (grain yield/the amount of N, P, or K applied), internal nutrient efficiency (grain yield/the total uptake of N, P, or K at maturity), and harvest index of nutrients (uptake N, P, or K in grains/ the total uptake of N, P, or K in plants at maturity), and significantly decreased the absorption amount of nutrients for grain production (the total uptake of N, P, or K in plants at maturity/grain yield). The results suggest that both wheat and rice absorb relatively smaller nutrients at early growth stages and more nutrients during the mid and late growth period, and the uptake and use efficiency of nutrients could be increased under the super-high-yielding cultivation.
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