ECO-PHYSIOLOGICAL RESPONSE OF SELECTED FARM TREE SPECIES UNDER SALINE FIELD CONDITIONS AFTER TREATING WITH ORGANIC AMENDMENTS DURING NURSERY STAGE

摘要

Salinity is a global issue and afforestation of degraded soils is the most sustainable approach to combat salt toxicity but trees have to suffer during their early growth in these soils. Under local set of climatic conditions,organic soil amendments are re-ported to enhance the yield of cultivated crops but their effects and efficiency on trees during their es-tablishment in saline soils is not reported vet. This study was designed to check the transferability ofthe effect of different organic amendments on tree estab-lishment in salt affected soils. In the present study, various organic amendments applied at early growth stages, to assess the survival rate, morphological and physiological attributes of three selected agrofor-estry species: Eucalyptus camaldulensis Dehnh, Vachellia nilotica (L.)P.J.H.Hurter amp; Mabb. and Dalbergia sissoo Roxb., in saline field conditions. Six different types of organic amendments: farmyard manure (FYM), poultry manure (PM), slurry(SL), sugarcane bagasse biochar (SCB), woodchips bio-char(WCB)and farmyard manure biochar(FYMB), were applied to check the response of selected tree species against salinity in field conditions. Survival rate was observed in the order of E.camaldulensis >V. nilotica>D. sissoo against all applied organic amendments. Maximum height increment was ob-served for FYMB in alltree species under saline con-ditions:46.22 cm(E.camaldulensis),18.63 cm(V. nilotica),8.50 cm(D.sissoo)as compared to other treatments. Photosynthetic and transpiration rates were greater for FYM and were maximum in E. camaldulensis and minimum in D.sissoo, whereas, chlorophyll contents and stomatal conductance were higher for FYMB in E. camaldulensis as compared to other species and treatments. Higher amounts(mg g-1)of leaf Na+ and K+ were observed for control (6-8.6) and FYMB(6.3-8.06),respectively as com-pared to other treatments. All types of biochar treat-ments showed more promising results and can be recommended for future afforestation programs.