| In order to identify the difference of the highest population productivity of N fertilizer (HPPNF) and its growth factors of different rice varieties, a field experiments were carried out with50early-maturing late Japonica rice varieties representative in the region of Yangtze River under seven nitrogen applying levels (0、150.0、187.5、225.0、262.5、300.0、337.5kg/hm2) in2010and2011on the farm of Yangzhou university. And seedlings were raised with plastic plate. The highest value of rice yield under different nitrogen levels was defined as HPPNF. According to HPPNF, rice varieties could be classified into four types including top level (HPPNF≥10.50t/hm2), high level (9.75t/hm2＜HPPNF＜10.50t/hm2), middle level (9.00t/hm2＜HPPNF＜9.75t/hm2) and low level (HPPNF≤9.00t/hm2). On this basis, the accumulation, distribution and translocation of NPK of the four types rice varieties were studied. The result could be provided theoretical and practical basis for breed improvement and selection of varieties. The main results were as follows:(1) N accumulation of rice plant increased as the productivity level decreasing at elongation and deceased as the productivity level decreasing at hearing and maturity. The was a significant difference between N accumulation of four productivity levels at maturity, the top level was3.47%,7.98%and11.07%higher than three other levels, respectively. Before heading, N was mainly concentrated in the leaf, the ratio of leaves were respectively68.72%-69.55%and54.83%-56.78%at elongation and heading. After heading, N was mainly concentrated in panicles, the ratio of panicles were56.01%-58.44%at maturity. N concentration and accumulation of leaf at heading and N accumulation of leaf and panicle at maturity decreased as the productivity level decreasing.The rate of N accumulation of rice plant were increased as the productivity level decreasing from sowing to elongation, while the rate of N accumulation of rice plant were decreased as the productivity level decreasing from elongation to heading and from heading to maturity. The N accumulation of panicles from heading to maturity were decreased as the productivity level decreasing, the top level was3.14%,13.70%and16.71%higher than other three levels, respectively. The N translocation of leaves of top level was3.78%,7.67%and14.85%higher than other three levels, respectively. But, the TCRV (translocation conversation rate of vegetative organ) of which were smaller than other three levels.There were significant negative correlations between N accumulation and HPPNF before elongation, while there were significant positive correlations between them from elongation to heading and from heading to maturity. Also, there was a significant positive correlation between N translocation of leaf and HPPNF. N accumulation and translocation of leaves of top level of varieties were showed a clear advantage than the other three levels of varieties after heading.(2) P accumulation of rice plant increased as the productivity level decreasing at elongation and deceased as the productivity level decreasing at hearing and maturity. The P accumulation of top level was2.54%,5.28%and12.42%higher than three other levels, respectively. Before heading, P was mainly concentrated in the stem-sheath, the ratio of leaves were respectively64.26%-66.44%and65.25%-67.45%at elongation and heading. After heading, P was mainly concentrated in panicles, the ratio of panicles were60.59%-63.77%at maturity. P accumulation of leaf at heading and P accumulation of leaf and panicle at maturity decreased as the productivity level decreasing.The rate and amount of P accumulation of rice plant were increased as the productivity level decreasing from sowing to elongation, while the rate and amount of P accumulation of rice plant were decreased as the productivity level decreasing from elongation to heading, and from heading to maturity, the rate of P accumulation of rice plant were decreased as the productivity level decreasing. The ratio of P accumulation from elongation to heading was45.85%-50.99%, which is the highest during the whole growth stage of rice. The P accumulation of panicles from heading to maturity were decreased as the productivity level decreasing, the top level was3.10%,10.58%and14.09%higher than other three levels, respectively. The P translocation of leaves of top level was1.07%,9.46%and18.33%higher than other three levels, respectively.There were significant negative correlations between P accumulation and HPPNF before elongation, while there were significant positive correlations between them from elongation to heading. Also, there was a significant positive correlation between P accumulation of leaf/stem-sheath from elongation to heading and HPPNF. P accumulation of top level of varieties from elongation to heading was showed a clear advantage than the other three levels of varieties, especially P accumulation of leaf. The P accumulation of leaf and panicle of top level were higher than other three levels at maturity.(3) K accumulation of rice plant increased as the productivity level decreasing at elongation and deceased as the productivity level decreasing at hearing and maturity. The K accumulation of top level was3.65%,5.78%and7.22%higher than three other levels, respectively. K was mainly concentrated in the stem-sheath, the ratio of leaves were respectively64.92%-65.91%,67.92%-69.15%and58.71%-59.14%at elongation, heading and maturity. K concentration of stem-sheath at three stages, K accumulation of stem-sheath at heading and K accumulation of panicle at maturity decreased as the productivity level decreasing.The rate of K accumulation of rice plant were increased as the productivity level decreasing from sowing to elongation, while the rate and amount of K accumulation of rice plant were decreased as the productivity level decreasing from elongation to heading, and the rate of K accumulation of rice plant were decreased as the productivity level decreasing from heading to maturity. The ratio of K accumulation from elongation to heading was48.64%-57.30%, which is the highest during the whole growth stage of rice. The K accumulation of panicles from heading to maturity were decreased as the productivity level decreasing, the top level was3.43%、9.57%and13.09%higher than other three levels, respectively. The K translocation of leaves of top level was7.41%,7.03%and8.88%higher than other three levels, respectively.There were significant negative correlations between K accumulation and HPPNF before elongation, while there were significant positive correlations between them from heading to maturity. Also, there was a significant positive correlation between K accumulation of leaf/stem-sheath from elongation to heading and HPPNF. K accumulation of top level of varieties from elongation to heading was showed a clear advantage than the other three levels of varieties, especially K accumulation of leaf and stem-sheath. The K accumulation of stem-sheath and panicle of top level were higher than other three levels at maturity. |
PDF Full Text Request