Statistical Studies on Various Characteristics of Crop Plants : II. Varietal differences of morphological complex characteristics in rice at different planting spaces.

Abstract

Studies were performed on the varietal differences of the morphological complex characteristics in rice varieties at different planting spaces. Spacing between plants in the row employed in this experiment was 5 cm and 25 cm, while spacing between rows in both plots was 20 cm. In the previous paper (3), the normal planting space was 15 cm within the row. All the other neccessary materials and methods in the present case were in accordance with the previous experiment (3). The results are as follows : (1) The complex characteristics of rice varieties in the 5 cm-plot can be shown by two principal components as indices of complex characteristics, and on the other hand in the 25 cm-plot it can be shown by three indices as in the case of 15 cm-plot. These indices of complex characteristics are : 5 cm-plot: X₁=-0.371x₁+0.462x₂+0.525x₃+0.548x₄+0.144x₅+0.152x₆ X₂=0.503x₁-0.091x₂-0.094x₃+0.012x₄+0.646x₅+0.662x₆ 25 cm-plot: X₁=0.563x₁-0.188x₂-0.463x₃-0.467x₄+0.126x₅+0.233x₆ X₂=0.215x₁+0.288x₂+0.259x₃+0.387x₄+0.705x₅+0.604x₆ X₃=0.011x₁+0.860x₂-0.027x₃-0.027x₄-0.181x₅+0.178x₆ (2) The meaniag of these indices in the 5 cm-plot is as follows: The first index is mainly concerned with the plant type whether the the variety is a shortculmed, tiller-number type or a long-culmed, panicle weight type, and the second index is mainly concerned with its per plant yield. (3) In the 25 cm-plot, the weaning of each index is the same as in the 15 cm-plot. (4) In any case, it seems that the complex characteristics of rice varieties in each plot under the standard fertilizing conditions can be shown by the three factors : the plant type whether the variety is a tiller-number type or a panicle weight type, the per plant yield, and the plant height.