Table 5 Methods of observation and measurement.

Plant type

We observed the plant type in sampling process after two month cultivated, and the plant type was divided into three types, including erect, semi-erect and grovel type. The plant height (the base of the stem to the top) was measured and calculated.

Stem

The color of plant was also observed in mature period, and the plant color was divided into three types, red-brown, red and green. The plant stem diameter was measured at the base of the main stem using slide caliper rule. The number of stem nodes was calculated using magnifier.

Leaf

On the other hand, we observed the shape of leaves and petioles using magnifier.

Flower

We observed the inflorescence type, perianth, length of pistil and stamens during the florescence.

Seed

We collected the mature seeds and the following indexes were observed, including seeds color, seeds shape and seeds winged.

Thousand grain weight

Count out one thousand seeds randomly, measure the weight then take the average.

Protein content

Weigh 10 g seeds, the shells of seeds were removed and smashed into powder, and the powder was filtered through a mesh screen (aperture: 0.25 mm) for determination. The content of protein was determined by Kjeldahl’s method.

Amino acid content

The content of amino acid was determined by Hitachi 835-50 Automatic Amino Acid Analyzer.

Flavonoids in seeds

Weigh 1 g of each sample, heated and extracted repeatedly with methanol. 0.5 ml of extracted solution was taken into a test tube, and 10 ml of aluminum chloride in anhydrous methanol was added. After blending, the flavonoids content was determined with colorimetry.