The effect of different treatment on seed germination of Echinochloa crusgalli was investigated in this study. The results showed that GA3, concentrated sulfuric acid, KNO3, NaOH and temperature treatments all could promote the germination of E. crus-galli seeds, but there were great differences in the promoting effect. Seed soaking with 1 000-1 500 mg/L of GA3 for 24 h and seed soaking with concentrated sulfuric acid for 15-20 min all maintained the germination rate of E. crusgalli seeds higher than 70.0%; 1.5% NaOH made the germination rate of E. crusgalli seeds up to 93.7%, but higher-concentration NaOH significantly reduced the germination rate of E. crus-galli seeds; KNO3 treatment showed certain promoting effect on germination of E. crus-galli seeds, but the effect was not ideal, i.e., the germination rate was lower than 35.5%; 20-25 ℃ temperature treatment could effectively promote the germination of E. crus-galli seeds, and the germination rate ranged from 68.2% to 75.8%.
以第四纪红黏土发育的红壤、2年生宫川温州蜜柑(Citrus unshiu Marc.cv.Miyaga Ma Mase)盆栽幼树为材料,采用土壤水分探头(FDR)实时监测红壤水分含量,控制红壤水分设5个处理:SMC30、SMC45、SMC60S、MC75和SMC90(分别代表红壤相对含水量的30%、45%、60%、75%和90%),研究了红壤水分条件对柑橘幼树根、叶、春梢和横径的影响。结果表明,当红壤水分为SMC75时最适合柑橘幼树生长,且柑橘幼树根、春梢和横径及叶面积、周长、宽生长参数均在此处理时达最大值。幼树根生长指标(根体积、总根长、根上下扫描面积和根表面积)均与红壤水分间呈极显著抛物线相关,叶形态指标(叶面积、叶周长、叶宽、叶长、叶长/宽比值、叶形状因子)以SMC75为界,随着红壤水分的增加或减少,其生长量均受到了一定程度的影响。SMC≤45%,幼树春梢长和横径受到显著抑制。
