土壤水分对柑橘叶片生长及多胺代谢的影响

本文以2年生宫川温州蜜柑(Citrus unshiu Marc.cv. Miyagawa Wase)盆栽幼树为材料,研究了土壤相对含水量(Soil Water Content,SWC)对橘叶生长和叶片多胺(腐胺Put,亚精胺Spd,精胺Spm)代谢的影响.结果表明:SWC由30%增加到90%,橘叶面积、叶周长、叶宽值均在75%时达最大值12.25 cm2、13.84 cm、3.19 cm,且叶面积、叶周长、叶长、叶宽均与SWC呈显著线性正相关;橘叶Put在SWC=75%时最低(228.95 nmol/g,FW),Spd和Spm均随土壤水分递增呈抛物线变化,其最大值分别出现在45%和60%.(Spd+Spm)/Put的比值与叶面积、叶周长、叶长、叶长/宽间呈显著或比较显著负相关,且当SWC≤75%时,此比值(t)与SWC(x)间呈显著正相关(t＝0.0112x + 0.173, p＜0.05).因此,(Spd+Spm)/Put比值可视为柑橘对土壤水分环境敏感度的指标之一.

Effects of Soil Water Content on Growth and Polyamines' Content for Citrus Leaves

In this study, two-year mature satsuma mandarin trees (Citrus unshiu Marc.cv. MiyagaMa Mase) in red soil derived from Quaternary red clay were selected as experimental materials to explore the effects of soil water relative content (SWC) on the growth and polyamines' content of citrus leaves. SWC was controlled from 30% to 90%. When SWC was 75%, the area, perimeter and width of the leaves all reached the maximal values, which were 12.25 cm~2, 13.84 cm and 3.19 cm respectively. And the above 3 indices all showed significant positive correlations with SWC. Putrescine (Put) content was the lowest (228.95 nmol/g, FW) when SWC was 75% while both spermidine (Spd) and spermine (Spm) contents increased by parabolic trends with SWC increase. The maximal contents for Spd and Spm appeared when SWC were 45% and 60% respectively. (Spd +Spm)/Put ratio showed significant or extremely significant negative correlations with the area, perimeter and length/width ratio of the leaves respectively. (Spd+Spm)/Put ratio (t) showed a significant positive correlativity with SWC (x) (t=0.0112x+0.173, p<0.05 ) when SWC was under 75%. (Spd+Spm)/Put ratio thus could be selected as a sensitive index for the effect of citrus on red soil water environment.