Show see wheat immune from rust injury experiments by specialists indicate old trouble Is inherited prepared by united states department ot of agriculture service wheat breeders bleeders bre eders of the department are a step nearer their goal of producing rust immune spring cheats several years of intensive experiments by department workers at the northern Noi thern great 1 plains lains field station at mandan and tho the langdon substation tit langdon N D proved almost con elusively that near immunity from stem stern rust Is a plant character definitely inherited in wheat crosses the recent results were reported by J allen alien dark clark and 11 II B humphrey of the division of ereal cereal crops and diseases at the annual meeting of tho the american society of agronomy held in washington tills this principle Is significant both for breeders bleeders bre eders and wheat farmers the ahe breeders bleeders bre eders are convinced that there Is such a character as near immunity from rust in wheat which Is inherited in a different manner than the character ac er 0 of resistance they have a long way to go before they can breed this near immunity in all wheat sown by farmers for they must cross near im mune varieties with resistant and susceptible cep tible ones that have all the other desirable characters such as high yield good milling and baking quality resistance si to hot weather drought and diseases other than rust however the knowledge that near immunity la Is a hereditary ch character arReter and not mer merely e a growth or plant condition is 0 of f t tremendous remen dous importance in wheat improvement pro in the early experiments to produce rust resistant cheats breeders bleeders bre eders crossed common and durum varieties most of these crosses were sterile hut but when they grew and were rust resistant they were like the durum parent discovery of resistance in kota common wheat in 1019 removed these difficulties this res resistance I 1 stance was a step forward but it wa was s not sufficient to elaml eliminate all possibility of loss in the first experiments crosses of hope with marquis and reliance behaved similarly the first plants grown from the cross had only a trace of rust in the second generation the plants grown from the seed of the first crop varied some being nearly immune immen 0 from rust some resistant and some susceptible but it was evident that the population tended toward near im in the third generation about 25 per cent of the strains bred true for near immunity but only about 6 per cent bred true for susceptibility there were also true breeding resistant strains like ceres and segregating strains in these wheat breeding experiments the government scientists delve deep into the genetic factors governing tile the near immune resistant and susceptible rust reactions of wheat they interpret their results in genetic language by saying that hope lias has a single CIO dominant inhibiting factor for near immunity that marquis and reliance have a major dominant factor of susceptibility that H 44 carries both of these dominant factors and that the resistant cores ceres Is represented by the double recess recessives ives |