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INUKKITANCE OF IVIOITLING ON SEED COAT 



Seeds of four generations of the Adzuki Bean are arranged above to show how the mottled 

 character of the seed coat is inherited in accordance with Mendel's law. In the original 

 parental generation, at the top, ])lants bearing dark mottled seeds are crossed with those 

 bearing unmottled seeds. The offsjjring (Fi) all have light mottled seeds. These Fi plants, 

 self-pollinated, produce on the average in the F2 generation one plant with dark mottled 

 seeds, two plants with light mottled seeds and one plant with unmottled seeds. The dark 

 mottled and the unmottled F2 plants breed true, while the light mottled ones break up in 

 the F3 generation giving again a 1:2:1 ratio for the mottling of seed coats. Seeds slightly 

 reduced in reproduction. (Fig. 10.) 



while the dark mottled and the un- 

 mottled forms breed true when sclfed. 

 This is so both for forms with red and 

 with Ki'ay seeds. 



The 1916 reeords for ()lTsi)rini,^ from 

 light mottled seeds from four dilTerent 

 lines are given in Table I below: 

 Table I 



This gives a total of 39\ mottled to 

 144 grays — a ratio of 2.72:1. Plants 

 that bear mottled seeds — either homo/^y- 

 gous or heterzygous — have red j)igment 

 in their stems. This is most notice- 

 able in the seedlings and in j^lants that 

 are rii^ening their seeds. Seeds may be 

 germinated in the laboratory to show 

 the uniformity of seedlings from homo- 

 zygous plants, and segregation into a 

 3:1 ratio from heterozygous plants. 

 Adztiki Beans should be i)lantcd out 

 early since they are rather slow in 

 mattiring iheir seed. 



THi: JI.MSON WKi-:u 



The Jimson Weed is of value from 

 the ease witli which it can be handled. 

 It may be grown to maturity in a 3-inch 

 pot or, if given good garden conditions, 



126 



