196 



Proceedings of Indiana Academy of Science 



in September where there was considerable defoliation due to Sep- 

 toria leaf-spot. 



As a result of the very prevalent growth-crack and corn ear worm 

 injury to the fruit combined with the frequent rains during the picking 

 season, fruit rots were very prevalent this season. In 1920, a row of 

 southern-grown plants infected with nematode root-knot were grown in 

 an experimental plot at Lafayette and in 1921 tomatoes were grown in 

 the same soil. The development of a few galls on the roots of the 1921 

 crop proved that some of the nematodes had withstood the winter. The 

 persistence of these nematodes in the soil under Indiana conditions justi- 

 fies our previous warning against the use of infested transplants. 



A number of non-parasitic injuries and diseases were noted among 

 tomato plants. The field trouble known as hollow-stem wilt was re- 

 ported from Madison County during the July drouth. An upward roll- 



Fig. 10. Turnip yellows. Typical one-sided effect of the disease: one side of plant 

 affected -worse ; one-half of central leaf affected worse, resulting in curvature, asym- 

 metry, and yellowinR of the stunted side. 



ing of the leaves called leaf-roll occurs generally in staked tomatoes in 

 market gardens and hothouses. Giissow (25) and others have attrib- 

 uted this trouble to excessive pruning of the plants. In the spring the 

 tomato seedlings in certain sections of a greenhouse bench at Lafayette 

 showed considerable scalding of the foliage. On days of bright sun- 

 shine, it was noted that the location of the injured plants coincided 

 rather closely with strip.s of intense light which were found to be due 

 to the focusing of the sun's rays by the .slight cylindrical curvature of 

 certain panes of glass in the roof. 



Turnip. — Yellows caused by Fusa/rium conglutinans was found very 

 serious in a market garden near Lafayette on June 4 where cabbage 

 yellows had occurred before. Many plants were aff"ected and typical 

 symptoms were displayed, such as the one-sided yellowing and subse- 

 quent curvature of the leaves, death of the leaves on one side of the 

 plant (fig. 10), general stunting of the whole plant, and a brown dis- 



