Corn Planting Date and Plant Population
1994; Wiley; Volume: 7; Issue: 1 Linguagem: Inglês
10.2134/jpa1994.0059
ISSN2689-4114
Autores Tópico(s)Growth and nutrition in plants
ResumoJournal of Production AgricultureVolume 7, Issue 1 p. 59-62 Research Corn Planting Date and Plant Population Emerson D. Nafziger, Corresponding Author Emerson D. Nafziger n/a@.dne Dep. of Agronomy, Univ. of Illinois, 1102 S. Goodwin Ave, Urbana, IL, 61801 Corresponding author.Search for more papers by this author Emerson D. Nafziger, Corresponding Author Emerson D. Nafziger n/a@.dne Dep. of Agronomy, Univ. of Illinois, 1102 S. Goodwin Ave, Urbana, IL, 61801 Corresponding author.Search for more papers by this author First published: January-March 1994 https://doi.org/10.2134/jpa1994.0059Citations: 69 Research supported by Pioneer Hi-Bred International and by the Illinois Agricultural Experiment Station Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Abstract Predictions of yield responses to planting date and plant population in corn (Zea mays L.) are necessary in order to match plant population to a particular planting date, and also to make replant decisions. Much of the published research on these factors is relatively old. This study was conducted at Monmouth and DeKalb, Illinois for 4 yr (1987–1990) in order to formulate a predicted response of two modern hybrids to planting date and plant population. The two hybrids in the study showed no consistently different yield response to planting date, to plant population, or to the interaction of these two factors. Generally, yields increased from mid-April to late April planting dates, then declined as planting was delayed to late May. Plant population had a very large effect on yield, except in the very dry environments at Monmouth in 1988 and 1989. The model found to give the best prediction of response to planting date and plant population was Yield (bu/acre) = 23.96 + 1.659D − 0.0303D2 + 7.673P − 0.1266P2, where D = days after 1 April and P = plant population in thousands per acre. The population providing the highest yield was about 30 310 plants/acre, and the best planting time was found to be about 27 April. The table of predicted values from this study can be used to provide more accurate information on planting date and plant population responses of newer hybrids, and will be useful in making replant decisions when the initial planting is early enough to allow assessment of stand damage by mid-May. Research Question It is essential that producers know how corn yields respond to planting date and plant population in order to optimize yields and to help make corn replanting decisions when stands are incomplete. There is a great need to update information on optimum planting date and plant populations using newer hybrids and management practices. Literature Summary The most widely used information about how corn hybrids respond to planting date and plant population was generated from research done about 15 yr ago, in which the first planting dates were late April or early May and the highest plant population used was 25 000 plants/acre. That study identified 6 May as the optimum planting date, and yields were still increasing at the highest plant population. A few other studies have been published in state extension bulletins and newsletters, but a recent review of this topic points out the lack of current information. Study Description Two corn hybrids—Pioneer Brand 3732 and Pioneer Brand 3615—were planted on four dates ranging from mid-April to late May on a Drummer silty clay loam soil at DeKalb, IL, and on a Muscatine silt loam soil at Monmouth, IL, in each of the 4 yr 1987 to 1990. High levels of fertility were maintained throughout the study. Populations ranging from 10 000 to 35 000 plants/acre were established after emergence. Growing season moisture was adequate for good yields each year at DeKalb, but was deficient at Monmouth in 1988 and 1989. Applied Questions What are the best planting dates and plant populations for corn? The model developed from the results of this study showed the best planting date to be 27 April, and the best population for the two hybrids to be about 30 300 plants/acre. Yield losses accelerated as planting date moved earlier or later, or as plant population increased or declined from the optimum. Should plant population be changed according to the planting date? There was no interaction between planting date and plant population, meaning that final plant population should not be changed as planting date changes. If planting is delayed, however, seed rate should perhaps be decreased slightly in expectation of a higher percentage of the seeds emerging. Can we expect hybrids to differ in response to planting date and plant population? While we saw the two hybrids responding somewhat differently to planting date and plant population in the different environments, there was little consistency to these responses. How can these results be used to make replanting decisions? The following model was formulated based on the data from this study: Yield (% of maximum) = 14.71 + 1.018D − 0.0186D2 + 4.709P − 0.07768P2 Full scientific article from which this summary was written begins on page 59 of this issue. where D = number of days after 1 April and P = plant population in thousands per acre. This model was used to generate the following table: To use this table for replant decisions, simply assess the expected yield based on the original planting date and the present plant population, then see how much the yield would be increased if a full stand were re-established by replanting on a given later date. If the difference in expected yield will return more money than the cost of replanting, then replanting should be considered. Costs arising from higher grain moisture at harvest and greater European corn borer damage should be added to the replanting cost. Our last planting dates were in late May, and this model should not be extended into June. Other work has shown, however, that yields decline very rapidly as planting is delayed into June, with expected losses as high as 50% if corn is planted in mid-June. Plant population, thousands per acre Date 10 15 20 25 30 35 ------------ % of maximum yield ------------ 10 Apr. 62 76 86 92 94 93 20 Apr. 67 81 91 97 99 97 30 Apr. 68 82 92 98 100 98 9 May 65 79 89 95 97 96 19 May 59 73 83 89 91 89 29 May 49 63 73 79 81 79 Citing Literature Volume7, Issue1January-March 1994Pages 59-62 RelatedInformation
Referência(s)