1995 Volume 40 Issue 4 Pages 437-442
Seeds of seven legume species, white clover (Trifolium repens L.), alsike clover (T. hybridum L.), red clover (T. pratense L.), crimson clover (T. incarnatum L.), birdsfoot trefoil (Lotus corniculatus L.), alfalfa (Medicago sativa L.) and common vetch (Vicia sativa L.), were surface-sown on the Yellow soil surface under controlled conditions with 25℃ and 100% RH. Penetration percentage of taproot tips, mean days for taproot penetration, and hypocotyl and root growth of three adhesion types in germinating behavior were examined for five days to decide the adhering function of taproot hairs. The three adhesion types in legumes were contact-adhesion, partial-adhesion and non-adhesion type owing to adhering degree in the length of taproot hair developing zone. 1. Ninety percent of taproot tips of contact-adhesion type in white clover, alsike clover, birdsfoot trefoil and alfalfa penetrated into the soil, being significantly higher than that of partial-adhesion type. The same tendency was observed in germinating behavior in red clover, crimson clover and common vetch. 2. The mean day for taproot tip penetration of contact-adhesion type was shorter than that of partial-adhesion type in all species examined. Length and proportion of taproot exposing on the soil surface were shorter in contact-adhesion type than in partial-adhesion type. 3. The hypocotyl-root ratio in length was highest in contact-adhesion type, followed by partial-adhesion type and non-adhesion type. Therefore, good adhesion of taproot hairs to the surface enhanced the hypocotyl growth as compared with taproot growth, and poor adhesion of taproot hairs enhanced taproot growth. 4. Based on the present results, contact-adhesion type in germinating behavior would provide good establishment compared with partial-adhesion and non-adhesion type.
