Crop Science Journal of Natural Resources and Life Sciences Education
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Published in Crop Sci 18:112-114 (1978)
© 1978 Crop Science Society of America
677 S. Segoe Rd., Madison, WI 53711 USA
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Allan, A. Y.
Right arrow Articles by Darrah, L. L.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Allan, A. Y.
Right arrow Articles by Darrah, L. L.
Agricola
Right arrow Articles by Allan, A. Y.
Right arrow Articles by Darrah, L. L.

Effects of Three Cycles of Reciprocal Recurrent Selection on the N and Plant Population Responses of Two Maize Hybrids in Kenya1

A. Y. Allan and L. L. Darrah2

H611(R), a variety cross of two maize (Zea mays L.) populations improved by reciprocal recurrent selection, and H613(R), a topcross hybrid with the same male parent, were evaluated to determine if responses to N or population density had changed through three cycles of selection for yield. The evaluation was done with 40, 140, and 240 kg/ha N and 33,300, 44,400, and 55,500 plants/ha at three sites in western Kenya. Significant progress was made from selection in improving the yield of H611(R), but not H613(R). The rate of improvement of H611(R), 8.5% per cycle, agreed with past estimates. Both hybrids showed a significant (P<0.01) linear response to N and H613(R) had a significant (P<0.05) linear response to population density. The quadratic response of H611(R) to N was significant (P<0.05), that of H613(R) was not.

H611(R) showed a significantly (P<0.01) improved response to higher plant populations from cycle 0 to 3. H613(R) was found to respond more efficiently to N fertilizer than the unselected population.

Key Words: Zea mays L. • Maize breeding • Hybrid development • N response • Plant population response

1 Contribution from the Ministry of Agriculture of the Republic of Kenya, the East African Agriculture and Forestry Research Organization of the East African Community, the U. K. Overseas Development Ministry (Scheme R2989, Maize Agronomy Research Project), the USAID (Project 618-11-110-657, East African Food Crop Research), and the ARS, USDA

2 Formerly project leader and maize agronomist, Nat. Agric. Res. Stn., Kitale, Kenya; and formerly maize geneticist, USDA-USAID-EAAFRO, Nat. Agric. Res. Stn., Kitale, Kenya, now of USDA-ARS, Columbia, MO 65201.

Received for publication March 25, 1977.




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
The SCI Journals Agronomy Journal Vadose Zone Journal
Journal of Plant Registrations Soil Science Society of America Journal
Journal of Natural Resources
and Life Sciences Education		 Journal of
Environmental Quality
Copyright © 1978 by the Crop Science Society of America.