Effect of Nitrogen on Hull Traits and Its Causes in Yangdao6

<正> The experiments were carried out under solution and pot cultural conditions with rice Yang-dao6. Effect of nitrogen on hull size, weight and plumpness and its relationship with plant nutrition were analysed. On comparison with no fertilization, low N application concentration from transplanting to heading, or employing basal fertilizer or tiller promoting one would result in increment of hull size and weight, while raising N application concentration from transplanting to heading or employing excessive spike fertilizer would result in smaller, lighter hull and poorer hull plumpness. The more amount of nitrogen applied, the