Vol. IX. So. 226. 



THE AGRICULTURAL NEWS. 



403 



variety, whicli then produce only liybriil seed. The impor- 

 tance of this fuiidiUiientHl ilitlerence between the Howeriiig 

 habits of corn and those of other crops hns not been sufficiently 

 appreciated. Systems of breeding develo]ied for other plant.** 

 have been ap[)lied to corn, diverting attention from this more 

 simple method of improvement, made possible by the peculiar 

 habits of the plant. The use of the first generation hybrids 

 will doubtless be found applicable to other crops, but in few 

 will its utilization be so easily accomplished as with corn. 



Comparatively few recent experiments with a direct 

 bearing on the value of first generation hybrids have been 

 reported, but all that have been made confirm the earlier 

 results. Taken in connexion with the experiments to be 

 reported in the present [laper, they establish beyond question 

 that the vigour of first generatim corn hybrids is a means of 

 securing increased production that is capable of very wide 

 application. As soon as the general public becomes acquainted 

 with such a simple and inexpensive means of increasing the 

 yield of this most important crop, a rapid extension of the 

 practice should follow. The great need is for detailed informa- 

 tion regarding the ;)articular varietal conditions best adapted 

 to the different local conditions. At present, the data arc .so 

 meagre that experiments must proceed empirically: but the 

 lack of detailed information should not nliscure the impor- 

 tance of the .subject, nor stand in the way of utilizing the 

 results already accomplished. 



Though the possibility of utilizing the vigour of first 

 generation hybrids is only beginning to be appreciated from 

 the scientific standpoint, the increased yields that result from 

 crossing have probably been utilized unconsciously since pre- 

 historic times. It is a regular custom among many native 

 American trilies carefully to plant .seeds of different varieties 

 in each hill of corn. This is done for the [lurpose of increa.« 

 ing the yield. Though the expected increase is usumHj 

 associated in the minds of the natives with superstitious 

 ideas regarding sexuality in the plants, the vigour secured 

 by such crosses may well have been an important factor in 

 establishing this custom with primitive tribes. 



The value of first generation hybrids is further recognized 

 in a widespread Ijelief among practical seed growers that the 

 plants produced by accidental crosses of jmre strains are 

 often exceptionally vigorous. 



After describing the woi-k tii.it has been lionc, so 

 far, in conne.xion with the subject, the bulletin procccils 

 to the folluwing conclusions: — 



The corn plant is naturally cross-fertilized and requires 

 the stimulus of crossing to produce maximum yields. Meth- 

 ods of clo.se breeding that can be applied toother ciops with 

 advantage do violence to the nature of the plant, and tend i" 

 reduce the vigour of growth and the yield of grain. 



As a result of the peculiar habits of reproduction of the 

 corn plant, the raising of hybrid seed does not require any 

 special skill or any large increase of labour. The cost involved 

 is insignificant in comparison with the increased yields that 

 are obtained. 



No reason is apparent why the vigour of hybrids may 

 not be regularly utilized to increase the yields of the corn 

 crop. A refusal to take this factor into account would lie 

 like rejecting the use of commercial fertilizers, or failing to 

 take advantage of the increase that may be obtained by 

 selective breeding. 



The planting of first generation hybrid seed as a method 

 of securing a larger crop is to be considered as entirely 

 distinct from the idea that superior varieties can be bred b\ 

 hybridizing or crossing. Cro.sses between distinct varieties 

 or strains at once increase the yield, but to maintain this high 



performance the cross must be made anew each year. 



Experiments to determine the value of first generation 

 hybrids have been made at various times since 1878, but in 

 an isolated and disconnected manner and u.sually without any 

 adequate appreciation of the possibilities of this method as 

 a regular element of farm practice. 



In the literature which has thus far been examined, nine- 

 teen crosses have been reported. With a single exception, these 

 hybrids gave larger yields than the average of the parents, 

 the amount ranging as high as 95 per cent. The series 

 includes experiments in six different states and embraces 

 a wide range of varieties. 



Similar increases are here reported in crosses between the 

 members of a new series of types of corn from China, Africa, 

 and the American tropics, very different from United States 

 varieties and very unlike among themselves. These experi- 

 ments show that a very wide application of this principle is 

 possible. 



In addition to increased yields, there is reason to believe 

 that the increased vigour of first generation hybrids may 

 become an important factor of adaptation to different condi- 

 tions of growth. The hybrids appear not to require the 

 delicate adjustment to local conditions necessary to the proper 

 performance of pure strains. The utilization of hybrids may 

 be expected to extend the range of utility of the high- 

 yielding types beyonil the present range of adaptation of such 

 varieties. 



First generation hybrids are a distinct factor in the 

 problem of securing varieties of corn with adaptations that 

 fit them for special conditions. The increased vigour which 

 these hybrids possess should make possible their growth in 

 regions where pure strains fail, and should also provide some 

 measure of disease resistance. 



The advantage of crossing distinct varieties is equally 

 applicable to the improvement of sweet corn, and affords 

 a measure of protection to those discovering new and valuable 

 combinations. 



RUBBER IN OEYLON. 



In 1909, the United Kingdom took a quantity in excess 

 of the entire exports of 1908. The United States of .Vmerica 

 is our next best customer, taking double the quantity she did 

 in 1908. After deducting Straits rubber sold in the local 

 market, the total quantity exported was as follows : — 



cwt. 



1908 7,808 



1909 13,621 



During the year, prices for rubber reached unprecedented 

 figures, influenced by a very stong demand and a short supply, 

 'I'lie record prices paid for Ceylon plantation rubber were 

 9<. 3^''/. per lb. in London, and lis. 7'20 in Colombo. The 

 year closed with a quotation at 7s. lid. for fine hard Para. 

 The Chamber of Commerce reports : — 



' Further points which deserve special mention are the 

 general improvement in, and greater regularity of, quality, 

 which have been noticeable during the year, many estates 

 (more particularly those making use of crepe machines) having 

 turned out rubber of such even quality, size, and colour, that 

 it has become customary to deal in the produce of such 

 estates on the mark alone, without samples, which has tended 

 to greatly facilitate business. 



' Statistics relating to importing markets show the posi- 

 tion at the close of the year to be exceptionally satisfactory 

 from a producer's point of view, and prospects for 1910 

 would appear to be all that can be desired.' (Cofonial Re- 

 ports — Annual, No. 653.) 



