There are many researches of simulative images or growth of biology with Lindenmayer system

but there are few researches on retrieved Lindenmayer gene set from a long Lindenmayer string. If Lindenmayer gene set can be retrieved from Lindenmayer string which can be obtained from image or growth of biology with other algorithms

the image or the growth of biology will be easier compressed or identified. Retrieving Lindenmayer gene set from a long Lindenmayer string which can be reverted with the set of Lindenmayer gene is researched in this paper. Base on iteration statistic laws of single symbol in Lindenmayer string

some valuable relationships of single symbol's quantities in iteration of Lindenmayer system are provided in this paper. The statistic laws of single 'growth' symbol can used for judge whether the Lindenmayer string is a iterated string quickly. Following to the relationships

the Lindenmayer gene set can be found out faster

and the relationships can judge the Lindenmayer gene set whether is true. First it can be got how many research sets from the count of single 'growth' symbol of the Lindenmayer string

then the length of string branch can be obtained with each set

and at last the Lindenmayer string can be judged whether it is a iterate string

the iterate gene can be brought out if it is a iterated string. The relationships can be used with other retrieving algorithm (ex. Iterate gene algorithm) to run better.