Evaluating of rice genotypes tolerant to Fe deficiency with drip irrigation under the film mulch

ObjectivesRice is grown on calcareous soil and managed using drip irrigation under the film mulch technology in the Xinjiang Uyghur Autonomous Region, where rice often suffers chlorosis caused by Fe deficiency. Evaluating the Fe-stress tolerance of different rice genotypes is of great importance for screening suitable rice cultivar.

MethodsSix rice cultivars were selected and managed with drip irrigation under the film mulch method in this research. At seedling, tillering and mature stages of rice, the biomass, tillers, yield and Fe content were analyzed. Cluster analysis and subordinate function values analysis were used to identify the multiple parameters associated with iron deficiency tolerance.

ResultsThe 6 tested rice cultivars showed significant differences in resistance to iron deficiency at the seedling, tillering and mature stages. The leaf active iron contents of T-04 and T-05 were significantly lower than those of the other genotypes at seedling stage. T-201 had higher leaf active iron and Fe distribution in shoot at the seedling stage and leaf iron content and dry weight in shoot at tillering stage, T-04 had the lowest distribution of Fe in shoot at the tillering stage, while T-04 had the biggest tiller number. There were no significant differences in effective tiller number between T-04 and other genotypes, and yield of T-04 was the medium level. Cluster analysis showed that T-43 had higher indexes than other genotypes.

ConclusionsThe effective use of leaf iron and the ability of iron transfer ensure rice growth and higher effective panicle number, comprehensively considering iron nutrition efficiency and yield at all growth stages with drip irrigation under the film mulch, the rice cultivar T-43 has the strongest tolerance to iron deficiency, and T-04 shows the lowest tolerance at all growth stages.