Effect of Enhancing UV-B Radiation on the Number of Vascular Bundle and Spike Characteristic of Wheat

The effects of enhancing UV-B radiation on the stem vascular bundles and its relationship with spike characteristic of wheat were investigated. The results showed that under enhancing UV-B radiation, the grains per ear were significantly decreased which was mainly due to decreased the spikelets and the florets per spikelet. The experiment also showed that the stem vascular bundles were significantly decreased by enhancing UV-B radiation. There were very significantly positive correlation between the vascular bundles of top internode and the spikelets per ear. The wheat yield decrease under enhancing UV-B was partly attributed to the vascular bundle decrease of top internode.