_-. . lSIT to BELTSVILi.£ (Continued fro:n December Issue) 



Follov;ing are a few observp,tinns nade at tlie L'.S.L.A. Experii".ientai b arm i." 

 BeltSTille, Maryland: 



-Jtrawberries - In breedin;-; bett3r varieties ^ a planting of 6100 seedlings is 

 bting studied. The numbers of seedlings ejid the characteristics are as f ollov/r : 

 red stele resistance, 1283; late ripening, 1512; firmness, 1174; flavor, 684; 

 size, 171. A striking example of the longevity of pollen stored at a temperaturv 

 of about 40'^F. and relative humidity of 50% was observed. Year-old pollen store I 

 -mder these conditions .genuinated well and gave a good set of seed. 



Among the virus diseases are crinkle, curl, v/itches broom, yellows (yellov. 

 edge in England), etc. One of the virus diseases, common in the East, results i-i 

 shorter petioles on the Marshall variety and a tendency for the leaves to lie 

 on the ground. Practically all plants of certain varieties are n^n: infected, 

 ■w. attempt is being made to establish viras-free sources of our more important 

 varieties using the grafting method of determining the presence of virus in 

 doubtful plants. At present, plants of vs'even virus-free varieties have been 

 isolated: Dorsett, Klondike, Tiarshall, Culver, Robinson, and two I'arietie.-^ of 

 Tennessee origin. 



Peaches - In 'a study of mineral deficiencies, magnesium deficiency v/as found L" 

 show up first where both calcium aiid potassium are high. Calcium seems to be r. 

 partial substitute for both magnesium and potassium. It has a striking effect 

 or. root development. Tfliere calcium is lov;, roots are much restricted, Higii 

 c&lciuin means many fibrous roots. (A high nitrogen level v;as maintained in the 

 above study.) In breeding peach varieties for hardiness, stations for testing 

 are being established in various northern states. Up to ,20 or 25 trees are 

 •ivailable for this purpose. The University of Iiassachusotts is invited to 

 cooperate, 



iippl es - In a study of apple trees under lov;, medium, and high nitrogen levels, 

 uo difference in magnesium deficiency s^/mptoms v/as noted in the mediunfand high 

 .'litrogen levels but, in general, the smptoms were more severe on high, than on 

 -o\7, nitrogen trees. There seems to be a relation between night temperatures anu 

 -he coloring of apples. If apples mature at a time v^hen the nights are v/arm, 

 color is likoly to be inferior. One of the Beltsville workers told of a survey 

 in the I'lorthvv'est vrhich shows a relation betiveen the supply of nitrogen and yi^ld. 

 Tr.e optimum nitrogen level should be maintained, if possible, in every orchai-d. 

 -'•rJlo\7ing is a summary covering the yield in 25 orchards over a five-year perioc. 

 •i~rogcn fertilizers included ammonium sulfate, sodium nitrate, etc, 



N'umbor of Actual Pitrogen Packed Boxes per tree 



Orchards Applied (Piange from 1940-44) 



7 1 pound 5.3 - l?.l 



11 li-2ir pounds 7.5 - 15,1 



5 3-4 pounds 4.9 - 19 



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 '.•v. you ordered your ilif'.h lia^gnc^siujii, or Dolomitic Idmo ? Orchard soil? aro 

 v'.'ioii.irig incroaslngly aci"!," I.Iagnosiu:,i deficiency symptoms are present on a 

 iurv r: 'iingly large munber of farms. Uony orchards will be givntly mprorou 

 ■^y " £ ior.s j^er acre r..pplicati.on of High Ilagncsium Limo. 



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