关键词: 薏苡[45NL], 叶片[53CC, 67CC], 叶面积[45NE], 校正系数, 回归法

Abstract: The leaf size leaf area and leaf area measuring method of Job's-tears were studied. The results were shown as follows: The leaf length, width and thickness(SLA, specific leaf area) of Job's-tears varied with the varieties and the leaf position on the main stem. The medium-upper leaves on the main stem were usually larger and thicker than the basal ones. The value of K, the calibrated coefficient used to calculate the leaf area with the leaf length and width, varied with the leaf position on the main stem too. The average K of 0.727 was calculated with the two varieties experimented. There were signifficant correlationships between leaf area(Y) and leaf length×width(X₁) and length/width(X₂), and the regression equations of Y=-0.286+0.7305X₁ and Y=-6.928+4.9268X₂ were found, which could be used to calculate the leaf area. The curve of leaf area per plant in the all growth stage fitted in with cubic equation. The SLA and leaf area of the plants in the dry-farming field which were moistured within all growth stages were larger than those in the irrigated field keeping 3-6cm thickness of the water within all growth stages. The leaf area per plant was largely composed by the tiller leaves while the leaf area of the leaves on the main stem was largely composed by the medium-upper ones at the medium-late growth growth stage.

Key words: COIX·LACRYMA-JOBI, BLADES, LEAF AREA, REGRESSION METHOD, CALIBRATED COEFFICIENT