Effect of Shading on Tonkan Orange (Citrus Tankan Hayata) I.The Effect of Shading on Wind Injury, Fruit Quality, Size, and Rate of Fruit Growth

This experiment was carried out at a site near sea coast of Tansuei, Taipei Prefecture. The results may be summarized as follows: 1. Tonkan fruits grown under shading were outstanding for smoothness and attractiveness of appearance, it may have some relation between the size and number of oil gland of the fruit. 2. The percentage of wind injured scurf appeared on fruit was found less on shaded plots than those in the plots without shading. It gave the evidence that interplanting of Acacia would also be effective as windbreak. 3. Sun scald was lower in the shaded plots than in the plots without shading. 4. The growth rate of fruit was reduced under dry condition, almost no growth was found in the plots without shading during dry condition. 5. The fruit juice obtained from shaded plots had more acidity than those of from the plots without shading. This is perhaps due to the late maturity of fruit under shading. Thus the fruits in shaded plots should be harvested later than those in the plots without shading.