부산대학교 도서관

The problem associated with soil salinity and lead (Pb) pollution is alarming for food crops production in arid and semi-arid regions of the world. To investigate Pb tolerance in rice cultivars under salt-affected conditions, a study was conducted at the Institute of Soil and Environmental Sciences, University of Agriculture, Faisalabad-Pakistan during the year 2013. Two rice cultivars viz. Shaheen Basmati and KS-282 were exposed to varying levels of Pb i.e. 0, 100, 200 and 300 kg ha-1 as Pb(NO3)2 in both normal and salt-affected soils. The tolerance indices and effect of relative toxicities on different plant parameters like plant height, straw dry matter and paddy yield were more prominent in salt-affected Pb-contaminated soil than in normal Pb-contaminated soil. In general, with Pb application, Pb tolerance indices on growth parameters were higher. However, relative Pb toxicity was found to be lower in Shaheen Basmati than KS-282. The tolerance indices for paddy yield were 64.9 and 52.9% for Shaheen Basmati and 43.8 and 38.7% for KS-282 at 300 kg Pb ha-1 in normal as well as salt affected soils. Applied Pb affected the photochemical efficiency which was significantly (P ≤ 0.05) more in KS-282 than Shaheen Basmati. The total chlorophyll contents in Shaheen Basmati at the highest level of applied Pb (i.e. 300 kg ha-1) was 30.1 and 23.2 SPAD-value, while in KS-282 it was 24 and 17.7 SPADvalue, in normal and salt affected soils, respectively. The results were significantly (P ≤ 0.05) related to the Pb uptake and translocation in both normal and salt-affected soils. On the basis of these results, it is concluded that Shaheen Basmati was more tolerant to Pb toxicity compared to KS-282 in both normal and salt-affected soils. [ABSTRACT FROM AUTHOR]