BLACK ROOT-ROT RESISTANT STRAINS 



OF HAVANA SEED TOBACCO 



FOR THE CONNECTICUT VALLEY 



By C. V. Kightlinger, Research Professor of Agronomy 



Havana Seed is one of the three principal types of tobacco grown commercially 

 in the Connecticut Valley, and the principal type grown in Massachusetts. It 

 is more or less susceptible to all of the diseases of tobacco in the Connecticut 

 Valley, of which black root rot is one of the most important. These facts warrant 

 persistent, earnest effort to find a satisfactory means of controlling the disease. 



The nature of black root rot and the general adaptability of the causal organ- 

 ism to environmental conditions make immunization the only control that can 

 be fully effective. There are promising prospects that strains of Havana Seed 

 tobacco can be produced by breeding which will be highly resistant to black root 

 rot and capable of producing good yields of tobacco of good type and quality 

 on land that is badly infested with the causal organism of the disease, as well as 

 being superior to regular Havana Seed tobacco on land that is relativeh* free of 

 the causal organism of black root rot and otherwise favorable to the production 

 of tobacco. Much progress has been made already to this end. 



The Importance of Havana Seed Tobacco in the Connecticut Valley 



The importance of Havana Seed tobacco in the Connecticut Valley and in 

 Massachusetts is shown in the following table: 



Table 1. — Havana Seed Tobacco and Its Relation to All 

 Tobacco in the Connecticut Valley.* 



Acres Yield Val 



Number Percent Pounds Percent Dollar? Percent 



(Havana of all (Havana of all (Havana of all 



Seedi Tobacco Seed) Tobacco Seed) Tobacco 



Connecticut Valley 



1943.. 6,500 34 10,960,000 39 4,129,000 20 



S-'sear average, 



'1939.43 7,500 35 12,960,000 41 3,400,000 24 



Massachusetts 



1943 4,300 83 7,267,000 88 2,761,000 63 



5-vear average, 



1939-43 4,700 82 8,302,000 88 2,147,000 66 



♦Figures aie based on estimates of Crop Reporting Service 



