440 EXPERIMENT STATION RECORD. 



jtercentage, describes the advantage of large seeds, heavy seeds and large- 

 seeded varieties, and calls attention to the higher lint percentages that diminish 

 fertility, to the large yields without high percentages, and to the high quality 

 with low percentages. 



It is shown that smaller or lighter seeds increase the percentages of lint 

 quite as effectively as an additional amount of fiber. A Mexican cotton with 

 27 per cent of lint hybridized by Egyptian cotton having a somewhat higher 

 percentage gave a progeny with a pei'centage of only 22.9, while the lint in- 

 creased from 4.0.5 gm. to 4.45 gni. per 100 seeds. The seeds, however, increased 

 from 10.95 to 14.75 gm. per 100 seeds. In order that a higher lint percentage 

 may be accompanied by an increased amount of lint it is necessary that the 

 weight of the seeds does not decline either by reduction in size or by change of 

 texture or compactness. 



The size of the seed is of practical importance apart from the question of 

 lint, mainly for the reason that there is an increased demand for cotton seed 

 for oil and other uses and that the presence of the boll weevil gives large seeds 

 a definite advantage. The large seed as a rule gives the young plant a better 

 start than a small seed and the more vigorous the seedlings the earlier the 

 varieties should be. It is shown that some of the early varieties like the King, 

 which has small seeds, small bolls, and short lint, may afford no better protec- 

 tion against the weevils than some of the large-seeded big-boll varieties. Early 

 opening of the bolls is not considered the best index of the amount of protection 

 obtained by early development. As long as the bolls are matured they are 

 beyond the reach of weevil injury and a variety setting bolls early and carrying 

 them past the danger of weevil infection may produce a larger crop in the pres- 

 ence of the weevils than the variety which ripens the first bolls. " The ideal 

 habit of earliuess would be met by a variety which could develop a large num- 

 ber of bolls past the point of weevil injury early in the season. Delay in the 

 date of opening might be an advantage if all the bolls would open together and 

 thus avoid the need of making several pickings of the same field." Other ad- 

 vantages of big-boll over small-boll varieties are pointed out. 



The author states that lint percentages can not be substituted for actual tests 

 of yield and that selection by lint percentages instead of increasing the agricul- 

 tural value of a variety may actually diminish it. On the other hand, it is 

 shown that large yields may be secured without high percentages. No neces- 

 sary connection between lint percentages and yields seems to exist, as very high 

 yields are obtained from varieties with relatively low percentages of lint. It is 

 pointed out that in Sea Island and Egyptian cottons the percentages fall below 

 those reached in some of our Upland varieties, but that high yields are not pre- 

 vented by lower percentages of lint. " Other things being equal, the high per- 

 centage varieties would always yield more lint, but it is evident that the other 

 things are often unequal and that the high percentages have no fixed connection 

 with vigor and fertility. Lint percentage is important as long as the other 

 features are not left out of account, but persistent selection for lint percentage 

 alone would be as likely to reduce the crop as to increase it." High lint 

 percentages are not considered as insuring high yields or high quality. With 

 greater length the percentage falls rapidly as the lint of carefully selected 

 varieties becomes longer. 



In discussing the true standai-d of yield in cotton the author points out that 

 the most direct indication of productiveness is not the proportion between the 

 lint and the seed but the proportion of the lint to the plant as a whole. A com- 

 parison of the weight of the lint with the weight of the plant would determine 

 how much in the way of other tissues the plant has formed in producing a given 



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