Submitted to: Society of America Plant Growth Regulator Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: November 24, 1999
Publication Date: N/A
Technical Abstract: Shoot growth of peach trees can be managed by manipulating edaphic condi- tions such as root volume and soil fertility. In this experiment two-year- old peach trees (Prunus persica L. cv. 'Sentry' on'Lovell' rootstock) were planted in pots with a split root design so that half the roots were not treated and the other half received one of four treatments: root volume re- -stricted with polypropylene nonwoven fabric (FAB); fertilizer alone (FER); FAB+FER; and untreated control(UTC). Total shoot growth and root growth were measured and root growth in the split halves was compared. FER in- creased leaf number and weight by 48% and 60%, respectively, but not stem growth. Leaf nitrogen concentration and photosynthesis were greatest in FER treatment. FAB did not affect shoot weight nor reduce total root weight or length, even though roots did not grow past the fabric barrier. FER in- creased root weight and length (116 and 57%, respectively, compared to UTC) )on the treated half but did not affect root growth on the untreated half. Greatest root growth occurred in the root half that received FAB+FER, part- icularly in the 5 cm soil segment proximal to the fabric (4.6 cm.cm-3 com- pared to 0.8 cm.cm-3 in UTC). Shoot length was greatest in FAB+FER & least in FAB. Thus, fertilizer applied near fabric increased root growth and the combination of fertilizer & fabric may be used to regulate shoot growth. Specific root length (root length per gram dry weight) was highest in trees with no treatment, suggesting root acclimation to low nutrient soil condi- tions. Lower specific root length resulted in soils that were fertilized. Results indicate that nonwoven fabric restricts root expansion in peach trees and reduces shoot elongation. Combined effect of fabric plus selected application of fertilizer may be used to regulate growth of peach trees.