Multiple regression analyses to estimate linear selection gradients (β) for trichome density, atropine, and scopolamine concentration in eight populations of Datura stramonium.

Significant gradients appear in bold-type fonts. Standard error (SE) of estimates, t-test value, and probability (P) are provided.

显著梯度以粗体字体标注。已提供估计值的标准误（Standard error, SE）、t检验值与概率（P）值。