Silicate improves growth and ion absorption and distribution in aloe vera under salt stress.
Si 2.0 mmol/L in irrigation solution alleviated significantly the inhibition of NaCl stress of 100 or 200 mmol/L to aloe growth. Exogenously applied Si decreased significantly Na(+) and Cl(-) contents, increased K(+) content and K(+)/Na(+) ratio and selectivity ratio of absorption (AS(K, Na)) and of translocation (TS(K, Na)) to K(+) and Na(+) in aloe plant under both NaCl 100 and 200 mmol/L stresses for 30 d. In this way, the ion homeostasis in aloe plant under NaCl stress was maintained, as was proved by X-ray microanalysis of root tip and leaf across sections. One of the mechanisms to achieve this may be the significant enhancement of H(+)-ATPase activities by the addition of silicate in plasma membrane and tonoplast, H(+)-pyrophosphatase (H(+)-PPase) activity in tonoplast isolated from aloe root tips under NaCl stress.
College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
Cheng-Xiang
CX
Xu
You-Liang
YL
Liu
Qing-Song
QS
Zheng
Zhao-Pu
ZP
Liu
D000042:Absorption; D000504:Aloe / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology; D004347:Drug Interactions; D007477:Ions / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism; D006180:Proton-Translocating ATPases / Q000378:metabolism; D012492:Salts / Q000378:metabolism*; D017640:Silicates / Q000494:pharmacology*; D012964:Sodium / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology*; D013312:Stress, Physiological
D007477:Ions; D012492:Salts; D017640:Silicates; D012965:Sodium Chloride; D012964:Sodium; D006180:Proton-Translocating ATPases; D011188:Potassium