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 Lee, S. S. Articles by Estes, G. O. Search for Related Content PubMed Articles by Lee, S. S. Articles by Estes, G. O. Agricola Articles by Lee, S. S. Articles by Estes, G. O.

Corn Physiology in Short Season and Low Temperature Environments¹

Northern areas seeking to expand corn (Zea mays L.) production and thereby reduce feed costs for livestock require early plantings of short season hybrids with good seedling vigor. The association between physiological behavior of corn to low temperature and its field performance could be important in selecting hybrids adaptable to such areas.

Twenty corn hybrids of commercial importance in New Hampshire which varied in maturity were planted 21 April and 19 May at the Univ. of New Hampshire Agronomy Research Station, Madhury, NH; nine selections from the above were also grown at three other locations in the state with widely differing growing conditions. The effect of controlled temperature on chloroplast structure and photosynthetic activity was also determined using the earliest and one of the latest maturing hybrids which differed in early development under field conditions.

Low temperatures following the early planting of 21 April did not adversely affect stand density of hybrids; seedling growth of the two earliest maturing hybrids was superior to all other selections. At the normal planting date of 19 May seedling growth of the 20 hybrids was negatively correlated with their maturity rank; seedling growth was greatest in the earliest hybrids.

Yield of total dry matter (TDM) at maturity was not related to seedling growth. In field studies in the southern and middle part of New Hampshire with a growing degree days (GDD) range of 1,100 to 1,300, TDM yields of the earliest corn hybrids were lower than yields of the later maturing corn. At the northern locations, with GDD < 1,100, yield of TDM was not significantly different among hybrids although % DM was higher in early maturing corn. A greater decline in photosynthesis and altered chloroplast ultrastructure in the leaves of a late-maturing corn following exposure to controlled day/night temperatures of 15/10 C in the greenhouse was observed; nosuch changes occurred at 15/10 C either in the earliest hybrid, which had shown superior seedling performance under field conditions, or in either hybrid when grown at 10/15 C.

Key Words: Yield • Chloroplast ultrastructure • Relative maturity • Growing degree days (GDD) • Photosynthesis

² Former research assistant (now Agronomist, Crop. Exp. Stn., O.R.D., Suweon, Korea) and Associate Professor, resp., Dep. of Plant Science, Univ. of New Hampshire, Durham, NH 03824.

Received for publication April 17, 1981.

This article has been cited by other articles:

				I. C. Madakadze, K. A. Stewart, R. M. Madakadze, and D. L. Smith Base Temperatures for Seedling Growth and Their Correlation with Chilling Sensitivity for Warm-Season Grasses Crop Sci., May 1, 2003; 43(3): 874 - 878. [Abstract] [Full Text] [PDF]