Rice root could restore the characteristic of negative phototropism when the new root cap grew up, if the original cells of root cap were well protected while root cap was divested.

• 剥除根冠而保留根尖的分生区和伸长区时,根能生长但失去负向光性,保留根冠的原始细胞时,当根冠重新长出时,又恢复负向光性生长。