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 Fontes, L. A. N. Articles by Ohlrogge, A. J. Search for Related Content PubMed Articles by Fontes, L. A. N. Articles by Ohlrogge, A. J. Agricola Articles by Fontes, L. A. N. Articles by Ohlrogge, A. J.

Influence of Seed Size and Population on Yield and Other Characteristics of Soybean [Glycine Max (L.) Merr.]¹

The wide variations in plant productivity found in growth regulation field experiments and observations in growers' fields strongly suggested the need to evaluate seed size as a factor affecting productivity. In greenhouse and field experiments small and large soybean [Glycine max (L.) Merr.] seeds were planted in a systematic arrangement and also in a random distribution after being remixed with the residual intermediate size seeds (bulk) and the difference in their competitive capacities was assessed at different populations. The effects of interplant competition were great as the result of variation in initial seed size. Plants from large and small seeds appeared to be affected differently. The grain yields from large-seeded plants increased, while those from small-seeded plants decreased when grown interspersed. Varying the proportion of large to small seeds planted variously affected the grain yield per plant, stem diameter, and number of barren plants. When grown in a bulk population, large-seeded plants had greater grain yield, more pods and branches per plant, and a smaller number of barren plants than small-seeded plants. The number of pods per plant was by far the most important yield component influenced by seed size. Varieties ‘Amsoy’ and ‘Wayne’ performed similarly in relation to all characteristics studied except the weight per seed and number of branches per plant. Lodging and number of barren plants increased with population, while grain yield per plant, number of branches and pods per plant, and seed per pod varied inversely to population. This suggests that plant uniformity, obtained by uniform seed size, may be basic in achieving higher yield levels.

Key Words: Interplant competition • Systematic planting • Population pressure • Seed grading

² Graduate student and Professor, respectively, Agronomy Department, Purdue University, Lafayette, Ind. 47907.

Received for publication .