Studies on the root-system of cucurbits. I

Abstract

The observation on the root-system of cucurbits have been conducted since 1956 at the Division of Horticulture, Kyushu Agricultural Experiment Station. This paper reports the results of observation concerning the differences in the root-system among varieties of watermelon from 1956 to 1958. 1. Following representative varieties were chosen: (1) Asahi-Yamato, adapted for the culture in the dry paddy field or clay soil; (2) Miyko No. 3, adapted for the soil of volcanic ash in upland area; (3) Fumin, selected in the warmer region; (4) Hybrids among the varieties mentioned abrgVe (5) Triploid and tetraploid varieties. 2. Asahi-Yamato variety has a shallow rootsystem consisted of horizontal main spreading near the soil surface and of slender roots. On the contrary, in Miyako No. 3 variety, many thick roots are seen in both upper and lower layers of soil, and many vertical roots extend deeper. 3. Hybrid strains have a vigorus root-system. Generally, their roots are thicker and longer, and are distributed in a deeper layer. 4. In polyploid varieties, the roots are thick and vigorous, and show many branching. Further, many vertical roots are distributed in deeper layers. 5. From the results of this observation, it may be considered that there is a close relationship between the characters such as vigor of shoots, heat resistance and fruit quality, and the root-system.