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 HighWire Citing Articles via Google Scholar Google Scholar Articles by Fischer, R. A. Articles by Kertesz, Z. Search for Related Content PubMed Articles by Fischer, R. A. Articles by Kertesz, Z. Agricola Articles by Fischer, R. A. Articles by Kertesz, Z.

Harvest Index in Spaced Populations and Grain Weight in Microplots as Indicators of Yielding Ability in Spring Wheat¹

A set of 40 adapted homozygous spring wheat (Triticum aestivum L.) genotypes were grown under similar conditions of irrigation and high fertility utilizing large plots and microplots seeded at normal densities, and spaced plants (60 x 60 cm grid). The objective was to see how well spaced plant traits, especially grain weight and harvest index, and microplot yields predicted true yielding ability as measured with the large plots. Phenotypic correlation coefficients were calculated using genotype means.

Microplot yield was highly correlated (r = 0.67 at the 1% level) with large plot yield but explained less than half of the variation between the genotypes. Much of the residual was probably related to the highly significant genotype X plot type interaction. With spaced planting, yield/plant was correlated (r = 033 at the 5% level) with crop yield. Better correlations with crop yield were obtained with plant and shoot harvest indices (r = 0.56 and 0.66, respectively, at the 1% level). No numerical components of yield measured on spaced plants gave better correlations with crop yield than yield per plant itself.

These results emphasize the major effect that the degree of interplant competition, probably primarily for Ught hi this case, has on the performance of a genotype. As the degree of competition declined going from crop plots to spaced plants, genotypes which can more fully occupy the increased space available were favored; thus, the performance of non-erect genotypes improved noticeably relative to erect ones. We conclude that harvest index measurement offers promise as a predictor of yielding ability where the seed available is limited.

Key Words: Triticum aeativum L. • Triticum turgidum L. • Competition • Phenotypic correlations • Yield components • Selection criteria

² Wheat physiologist (present address: CSIRO Division of Plant Industry, P.O. Box 1600, Canberra City, Australia 2601) and visiting scientist (present address: Cereal Research Institute, 6701 Szeged, P.O.B. 391, Hungary), CIMMYT, Londres 40, Mexico 6, D.F., respectively.

Received for publication February 10, 1975.

This article has been cited by other articles:

				R. M. Gifford, J. H. Thorne, W. D. Hitz, and R. T. Giaquinta Crop Productivity and Photoassimilate Partitioning Science, August 24, 1984; 225(4664): 801 - 808. [Abstract] [PDF]