Because of boron's involvement in cell growth, symptoms of boron deficiency are expressed at the growing tips of the root or shoot and generally include stunting and distortion of the growing tip that can lead to tip death, brittle foliage, and yellowing of lower leaf tips. If you are looking for high quality, high purity and cost-effective Boron powder, or if you require the latest price of Boron powder, please feel free to email contact mis-asia.