lo Sept., 1910.] Tlir \alue of Pedigree in Seed Wheat. 553 



THE VALUE OF PEDIGREE m SEED WHEAT. 



/. T . Pridliam, \Ylicat Experinieiifalist. 



A prominent feature of the work of the Wheat Improvement Committee 

 at the Longerenong Agricultural College is the production of selected or 

 pedigreed stocks of grain of the best varieties. While it is proposed to 

 increase the average wheat yield by breeding new varieties, we cannot over- 

 look the importance of maintaining the best of the old varieties up to a 

 high yielding standard until their place is taken by superior kinds. 



The sowing of wheat more or less thickly in rows by means of the 

 modern seed-drill makes individual differences in the wheat plants by no 

 means easy of detection. Where improvement is sought for, the individu- 

 ality of the wheat plant is often overlooked and the selection of a number 

 of large ears gathered here and there through the crop made the basis of 

 a fresh start with the variety. Large ears do not always spring from a 

 prolific plant so that mere size of ear is not a safe guide. 



In the case of maize, more attention has been given to seed selection 

 than with the wheat crop, and growers readily agree that the best practice 

 is to pick out the finest cobs for a seed plot to provide for field sowings. 

 Even better results are secured by sowing the grains from each of the 

 best cobs separately, thus securing a high-yielding strain from a single 

 individual. The best results of all are obtained when the alternate rows 

 are detasselled, thus preventing possible self-fertilization, and all barren 

 plants in the field cut out to prevent their pollen inoculating prolific plants. 



If wheat plants be isolated, each grain being sown separately as peas 

 in a row, the individual differences at once become apparent ; and wheat 

 lends itself more easily than maize to improvement as each plant inocu- 

 lates itself and reproduces its own characteristics without being affected by 

 its neighbours. 



Cases of natural cross-fertilization are known to occur, but where pure 

 pedigree seed is used little harm will result. In the moist climate of 

 England natural crossing is extremely rare — only three cases have been re- 

 corded ; but on the Continent of Europe it occasionally happens in warm 

 weather, and in India, Howard*, of the Department of Agriculture, says 

 five cases have recently come under notice at Lyallpur. Last season, no 

 less than six cases were detected at Longerenong, the seed having been 

 obtained from plants growing in field crops the previous season. 



New light is thus thrown on the notoriously impure nature (to the 

 trained eye) of seed which has been left to reproduce itself year after year 

 without selection. On most farms, two or more varieties of wheat are 

 grown and, unless the drill and har\ester are thoroughly cleaned out before 

 starting on a fresh variety, there will be admixture. Other sources of im- 

 purity are the transference of grains from one part of a paddock to another 

 in the process of harrowing after the drill when the soil is sticky ; catching 

 the edge of an adjacent variety in the harvester comb when turning; 

 the carrying of grain by birds ; the u.se of bags which have held wheat 

 before and have not been turned ; and the bagging up of loose grain from 

 the floor of the shed where wheat of more than one variety has been 

 stacked. Any variety of wheat will become more or less mixed unless the 

 stock of seed is renewed after a time from a pure source. 



* Memoirs of the Department of Agriculture in India.— A. Howard, M.A., and Col. C. Howard, M.A., 

 May, 1910 



