26 RELATION OF DROUGHT TO WEEVIL RESISTANCE IN COTTON. 



diminish or to disappear when the plants are grown under extreme 

 conditions of heat and humidity. 



Smaller injuries from weevils lend a relative advantage in dry 

 regions and in dry seasons. It is not safe to assume that improved 

 cultural methods, earliness of varieties, or special weevil-resisting 

 characters will have the same value in humid regions that they may 

 have shown in drv^ seasons in Texas. In the absence of the limiting 

 factor of drought, it is not safe to apply the analogies drawn from 

 Texas to the more eastern States. 



The problem of weevil resistance is especially acute in the humid 

 bottom lands of Louisiana and Mississippi, the chief centers of pro- 

 duction of the long-staple Upland varieties. Every possibility of 

 weevil resistance in the long-staple district is worthy of careful in- 

 vestigation, because special conditions of soil and climate make it 

 possible to produce superior grades not generally obtainable in other 

 parts of the cotton belt. 



Earlier maturing long-staple varieties that have been bred in the 

 United States or acclimatized from abroad may replace the present 

 long-staple varieties whose late-maturing habits render them more 

 susceptible to injury by the boll weevil, especially when grown in the 

 same localities with early short-staple varieties. 



Two additional measures of weevil resistance are also worthy of 

 careful consideration in humid regions, the development of quick- 

 fruiting long-staple varieties and the better organization of cotton- 

 growing communities so that only one type of cotton shall be grown 

 in the same locality, 



AAHiile the use of early-fruiting varieties and the early planting 

 of the crop are important in avoiding weevil injuries, both of these 

 policies have distinct limitations. Very early varieties may be rela- 

 tively unproductive, and too early planting may check the growth 

 of the seedlings, delay their development, and postpone the fruiting 

 period. The chief object is to secure the most rapid setting of a 

 good crop rather than the earliest opening of flowers or bolls. 



The early production of flowers or of ripe bolls does not prove that 

 a variety has the most effective form of earliness for purposes of 

 weevil resistance, especially if this precocious fruiting tends to re- 

 strict the growth of the plant. Rapidity of fruiting after fruiting 

 has once commenced is more important than absolute earliness, as 

 shown by the dates of the first flowers or the first open bolls. The 

 setting of a crop of bolls in the shortest time after the flower buds 

 begin to appear is the ideal form of earliness from the standpoint 

 of weevil resistance. This requirement of rapid fruiting should be 

 taken into account in the breeding of weevil-resistant varieties, as 

 well as in devising improved methods of culture for weevil-infested 

 regions. 



220 



