HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Fehr, W. R. Search for Related Content PubMed Articles by Fehr, W. R. Agricola Articles by Fehr, W. R.

Evaluation of Intergenotypic Competition with a Paired-Row Technique¹

A paired-row technique was developed to measure intergenotypic competition between soybean (Glycine max (L.) Merr.) cultivars. A paired-row plot consisted of two rows spaced 8 cm apart, the closest that we were able to grow soybeans in Iowa and still distinguish the individual rows at harvest. Different paired-row plots were grown 1 m apart. To evaluate the competitive interaction of two soybean cultivars, three paired-rows are needed per replication, one where the cultivars compete and one for each of the two cultivars in pure stand.

Intergenotypic competition in paired-rows was compared with that in a 1:1 blend grown in a single-row plot for nine cultivar pairs. A cultivar with tawny pubescence and a cultivar with gray pubescence were selected for each blend to permit separation of the cultivars at maturity. The individual cultivars were harvested separately in both the paired-rows and the 1:1 blend, and their yield performance was compared with that in a pure stand.

The paired-row technique was effective for determining the good and poor competitors in a blend for every cultivar pair tested. The percentage yield increase or decrease of each cultivar in competition generally was similar in the blend and the paired-rows. The data suggested, however, that growing cultivars in rows only 8 cm apart did not perfectly simulate the competitive interactions that occur in a 1:1 blend.

Key Words: Glycine max (L.) Merr. • Soybeans • Heterogeneity • Blends • Seed yield • Plot technique

² Gaastra, P. 1959. Photosynthesis of crop plants as influenced by light, carbon dioxide, temperature, and stomatal diffusion resistance. Meded. Landbouwhogeschool, Wageningen 59:1–68.