The effects of water-absorbing synthetic polymers on the stomatal conductance, growth and survival of transplanted Eucalyptus microtheca seedlings in the Sudan.
A polyacrylamide and a polyvinylalcohol added at two concentrations (0.2% and 0.5% v/v) to soil for transplanted seedlings receiving a range of irrigation treatments aided survival and growth. In the absence of irrigation, polymer additives almost doubled the period of tree survival, whereas under frequent irrigation transplant shock was reduced. When irrigated every 6 days, all of the control trees died whereas those with polymer additives achieved 57-71% survival. Measurements of stomatal conductances of leaves showed stomatal closure due to transplant shock and gave early indications of the longer term patterns of tree survival in relation to the various irrigation and polymer treatments. Polymer application cost between #0.010 and #0.016 per tree and would seem a cost effective way of increasing the success of tree planting in arid regions.