Lindane uptake and translocation by rice seedlings (Oryza sativa L.) under different culture patterns and triggered biomass re-allocation

The study was conducted to investigate the influence of the culture pattern on plant uptake and translocation of an organic chemical and the resultant acute response of plants, and to further reveal the interconnection. Plant exposure experiments were performed using a conventional rice seedling (Oryza sativa L. subsp. indica) under two kinds of culture patterns (viz., hydroponics and soil-based culture) with various culture matrices for a period of 7 days. The exposure concentration of lindane was ∼450 μg L−1 in the aqueous-phase matrices, and 200.1–756.0 μg kg−1 in the solid matrices. Lindane accumulation and its distribution in plant tissues were quantified, as well as the tissue biomass. The results showed the accumulation of lindane in all exposure groups were comparatively close over the period, confirming that the soil-bound lindane was scarcely available to plants. Similar trend of lindane uptake and translocation in seedlings was found among the groups under the same kind of cultivation pattern. In the hydroponic groups, lindane was mostly distributed in roots (about 60% at the end of exposure), whereas more lindane was translocated to shoots (approximate 70%) under the soil-based culture pattern. Allometric analysis demonstrated that the tissue part (root or shoot) with more lindane accumulation had a relatively higher growth rate over 7 days. Correspondingly, biomass allocation presented a slight trend of mutual proximity to lindane distribution. It was inferred that plants altered their allometric growth pattern to realize biomass re-allocation in response to the short-term lindane exposure, which could be considered as a plant defense strategy. [Display omitted] •The soil-bound lindane was scarcely available to rice seedlings compared to free-form lindane.•The lindane distribution modes in rice seedlings were different depending on the culture patterns.•The tissue part (root or shoot) with higher lindane accumulation grew at a faster rate.•Rice seedlings reallocated their biomass in acute response to lindane.