Dormancy and Storage 273 



Another means by which auxins can alter storage quality is 

 through the inhibition of molds and pathogens. It was reported in 

 1945 by Stevenson and Mitchell that 2,4-D would selectively inhibit 

 the growth oi certain bacteria without inhibiting fungal growth. 

 The selectivity of auxin inhibition of bacteria and molds offers real 

 possibilities for using auxins in the culture of molds in industrial 

 processes where specific strains of mold may be wanted. If the desirable 

 strain is not inhibited by auxin, then auxin may be added to the 

 substrate to inhibit the growth of contaminating molds. 



The development of molds on stored stock plants of shrubs and 

 trees is responsible lor considerable damage to these materials. Ap- 

 parently dipping or spraying nursery stock with auxins can greatly 

 retard mold development during storage (Marth, 1942; Way and 

 Maki, 1946). 



Mention has been made of the finding by Stewart (1949) that 

 citrus fruits treated with 2,4-D are less susceptible to Black Button, a 

 rotting of the stem end of the fruits. This type of breakdown of the 

 fruits in storage is due to the development of Alternaria rots and is 

 effectively controlled by pretreatment of the fruits with 500 mg./l. 

 of either 2,4-D or 2,4,5-T (Stewart et al, 1952). Curiously enough, not 

 only is the Black Button type of rot prevented but also, in the case 

 of lemons, the auxins appear to retard the yellowing and ripening 

 processes in storage. 



