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446 WELLENSIEK, HEREDITY OF STRINGINESS IN PHAS. VULG. VAR. 
- SUMMARY. 
Some varieties of Phaseolus vulgaris L. are characterized by the 
absence of strings on their pods. Three of these varieties: ,,Hin- 
rich's Riesen bonte stringless,” , Volgers stringless” and ,,Choco- 
lade bruine stringless’” were pollinated with pollengrains of the var. 
„Wagenaar”, that has a well developed string. In the F‚-generation 
of these crosses the stringlessnes was dominant while in the Fo- 
generation there appeared a monohybrid segregation, yielding the 
following segregation-numbers: 
1. Fa Hinrich's bonte stringless x Wagenaar. 
actual ratio: 41 stringless: 18 with string. 
theoretical expectation: 44,25 14,75 
mean error: +3,3 +3,3- 
deviation: — 3,25 +3,25 
2. Fa Volgers stringless x Wagenaar. 
actual ratio: 46  stringless: 12 with string. 
theoretical expectation: 43,5 14,5 
mean error: +3,3 +3,3 
deviation: +2,5 23 
3. Fo Chocolade bruine stringless x Wagenaar. 
actual ratio: 49 stringless: 25 with string. 
theoretical expectation: 55,5 185: 
mean error: : +3,7 +3,7 
deviation: 165 ve 46,5 
Taking together the results of the three crosses we get: 
actual ratio: 136  stringless: _ 55 with string. 
theoretical expectation: 143,25 47,75 
mean error: +5,9 … +59 
deviation: 2 +7,25 
The actual ratio agrees well with the expected results and'justi- 
fies the supposition that there exists a monofactorial difference 
between the above three varieties and the var. Wagenaar. 
Laboratorium voor Tuinbouwplantenteelt. Wageningen, 12.10.22. 

