Effects Of Organic Fertilizer On Development And Gene Expression Of Trichomes Of Flue-cured Tobacco

In order to analyze the effects of organic fertilizer on trichomes, taking the flue-cured tobacco K326 potted as experiment materials, we studied the morphology structure, secretion content, gene expression of middle leaves under organic fertilizer and chemical fertilizer during the developmental process. The main results as follows:1. Effect of organic fertilizer on trichome densityAs the development of tobacco leaves, both the trichome density in organic fertilizer treatment and in chemical fertilizer treatment showed downtrend. In each stage, the trichome density in organic fertilizer treatment was higher than that in chemical fertilizer treatment expect after transplanted 60 days. The significant analysis showed that the differences of trichome density between organic fertilizer treatment and chemical fertilizer treatment were not significant in fast-growing stage, but the differences reached extremely significant level in maturity stage. So we conjectured that applying organic fertilizer may delay the trichomes to fall off and provide advantages for material metabolism, osmiophilic globule releasing and secretion activity of trichomes.2. Effect of organic fertilizer on chlorophyll of trichomesThe chlorophyll content of trichome head cells in organic fertilizer treatment was higher than that in chemical fertilizer treatment in fast-growing stage, but the chlorophyll content was lower in organic fertilizer treatment after entering maturity stage. We conjectured that after the chlorophyll accumulation rapidly in prophase in trichome head cells of organic fertilizer treatment and beneficial to degrade in the late prophase. So applying organic fertilizer affected the development of trichomes.3. Effect of organic fertilizer on ultrastructure of trichomesThe content of osmiophilic globules in organic fertilizer treatment was more than that in chemical fertilizer treatment in fast-growing and maturity stages, the synthesis and accumulation rate were also higher in organic fertilizer treatment. We conjectured that the lipophilicity increased in organic fertilizer treatment which may lead to more osmiophilic material in trichome head cells.4. Effect of organic fertilizer on the secretion content of trichomesThe duvatriene diol content was more in organic fertilizer treatment than that in chemical fertilizer treatment in each stage. The secretion content under organic fertilizer showed the first increased and then decreased trend, but that in chemical fertilizer treatment continued to increase. Through significant analysis, the duvatriene diol which was the main secretion component reached significant level under different fertilizer treatment in fast-growing stage, and reached extremely significant level in maturity stage. So increasing organic fertilizer application was benefit to increase the secretion content to promote the quality of tobacco leaves.5. Effect of organic fertilizer on gene expression of trichomesPartial tobacco trichome genes changed under organic fertilizer. We used gene chips detected 1018 genes in total, differentially expressed genes was 93. Amid them, 42 appeared to be high expressed in organic fertilizer treatment (up-regulated), 28 appeared to be low expressed in organic fertilizer (down-regulated). Among up-regulated genes,mostly were concentrated in the chloroplast development, secondary metabolism, ion transportation and resistance while down-regulated genes mostly were concentrated in primary metabolism. We also detected some function- unknown genes, their differential expressed may have relationship with induction of organic fertilizer.