根系修剪对枳生长及相关基因表达的影响

以枳实生苗为试验材料,通过两年重复试验分析了不切除主根、切除1/3主根、切除1/2主根、切除2/3主根等4个不同水平根系修剪处理下枳实生苗生长发育、根系构型和营养吸收的情况,并检测了不同水平根系修剪处理对侧根发育关键基因表达量的影响.结果表明,切除1/2主根处理增加了枳实生苗的株高、茎粗、地上部鲜重和根系鲜重,改善了根...

Effects of root pruning on growth and expression of related genes in Poncirus trifoliata

In this study, Poncirus trifoliata seedlings were chosen as the test materials. The effects of four different root pruning levels (no cutting, cutting off 1/3 taproot, cutting off 1/2 taproot and cutting off 2/3 taproot) on the plant growth, root architecture system and nutrient contents of Poncirus trifoliata seedlings were investigated by a repeated experiment for two years, and the expression of key genes involved in the lateral roots development was analyzed under root pruning treatments. The results showed that cutting off 1/2 taproot treatment enhanced the height, stem diameter, shoot and root fresh weights, and improved the root system architecture parameters (the number of lateral roots, the total root length, the root surface area and average length), and also increased the contents of K, P, Ca, B, Fe, Na and Zn in roots of Poncirus trifoliata seedlings. In addition, quantitative real-time PCR (qRT-PCR) revealed that the expression levels of lateral root development related genes HOX1 and CYP2 were induced, but IAA11 and IAA13 were reduced under root pruning treatments. Overall, the moderate root pruning might regulate the development of lateral roots and improve the root architecture through up-regulating of HOX1 and CYP2 genes, and down-regulating of IAA11 and IAA13 genes, thus leading to the improvement of nutrient absorption and growth of Poncirus trifoliata seedlings.