Abstract:

With the development of agriculture, more and more nitrogen and phosphorus fertilizer were supplied in field rice growth in China. But in the mass, Kalium (K) was absent in many areas. Hyacinth could absorb large quantities of Kalium and concentrate them in their tissues. In this study, the field experiment was conducted to investigate the effects of hyacinth mulching on rice Kalium concentration, uptake, efficiency and allocation at different growth stages. Took ‘Yun 2645’ as material, the Kalium uptake and utilization of rice were evaluated under two different levels of N input: low (LN, 120 kg/hm2) and normal N (NN, 240 kg/hm2) in 2009. The results showed that: (1) Compared with AMB, hyacinth mulching significantly increased K concentration in rice plant over the season, and the increasing rate was gradual decline from mid-tillering to heading, but from heading to maturity the increasing rate was gradual addition, hyacinth mulching significantly increased Kalium accumulation in rice plant. (2) Hyacinth mulching had no obvious effect on Kalium allocation pattern in leaves and stems of rice over the season, significantly decreased Kalium allocation pattern in spikes at grain maturity. (3) Hyacinth mulching resulted in the significant decrease in K use efficiency for biomass (KUEp) over the season, K use efficiency for grain yield (KUEg) and K harvest index (KHI) decreased under hyacinth mulching. (4) Kalium concentration and accumulation at different growth stages of rice increased with increasing N supply (P < 0.01), but KUEp and KUEg showed the opposite trends. (5) Interactions between hyacinth mulching × N were not observed for K uptake and utilization. Hyacinth mulching increased K concentration and K uptake, decreased KUEp and KUEg at different growth stages of rice.