Abstract: The article??s aim was to understand the rules of light distribution for winter wheat under drought cond-itions.The methods were as follows: two winter wheat varieties were planted in pool and quantitatively irrigated. Light distribution of different fertility wheat canopy were measured using CI- 110 plant canopy analyzer under drought and irrigation condition. The results showed that LAI ascends early and then descends, and MLA or TCDP descend early and reascend for both Lm 21 and Jm 20; especially in 7. 5, 22. 5, 37. 5?? TCRP the differences were significant. Comparisons for drought and irrigation: drought made LAI descent, and TCDP became large for Lm 21, but it??s not significant for Jm 20. The effect of drought on the TCDP was 7. 5??TCRP less than irrigative, but the difference of TCRP were small at 52. 5??and 67. 5?? to deal with drought and irrigat ion. Drought increases K, but the difference of K were very small among 37. 5, 52. 5 and 67. 5??, the impact of drought on the distribut ion of leaves was unobvious. Comparison of different fert ility: the effect of high- nitrogen was small to MLA, TCDP in prophase, but was great to TCDP,TCRP in the latter stage. In the pre- birth, there were great effects to K at 7. 5??and 22. 5??.Drought on winter wheat canopy light distribution: drought leads to decline in LAI. Drought increases TCDP of Lumai 21 which is flat- leaf variety. In 7. 5??, TCDP and K were reduced. But the value of K was not change between 37. 5??and 67. 5??. Drought increases TCRP and K of Jm 20 which was stand-leaf variety in 7. 5??, however, the change was not much between 37. 5??- 67. 5??. Drought affects the light distribution of leaves in 0 to 90??, the impact of other angles were small;with the promote of fertility, TCDP and TCRP are f irst drop and then rise, but K was first rise and then drop.The indicator of light distribution of other canopy changes small.Different fertility conditions had an effect on LAI,TCRP,K,but had an smaller effect on TCDP,MLA and the distribution of leaves.

Key words: Winterwheat, Stand, Waterstress, Canopystructure, Lightdistribution

CLC Number: 

• S512.01??