Intercrop Productivity Research Articles

Effects of nitrogen supply and spatial arrangement on the grain yield of a maize/soybean intercrop in a humid subtropical climate

Cereal/legume intercropping is a common practice in low-input agricultural systems. Under appropriate conditions, it usually results in higher overall productivity as compared with pure stands. Appraisal of agronomic practices is of particular importance, since component crops sometimes differ considerably in their structure and fertilization needs. An experiment was conducted under the subtropical conditions of Southern Nepal, in the Terai belt, in 1988 and 1989. Maize (Zea mays L.) and soybean (Glycine max (L.) Merr.) received 0, 35 or 70 kg N ha−1 when grown either in pure stands or when intercropped in two spatial arrangements differing in spatial intimacy. Nitrogen fertilization resulted in similar grain yield increases for maize either in pure stands or in intercropping with soybean, indicating that the availability of nitrogen for the cereal was comparable in both cropping systems. Soybean yields were 22% lower in the presence of maize, as compared with a pure stand. The overall productivity of intercropping, as assessed by ATER (area-time equivalent ratio), was significantly higher than that of pure stands in 1988 and 1989. Land-use efficiency was higher when maize was intercropped with nodulating soybean, as compared to non-nodulating soybean, but only at 0 and 35 kg N ha−1.Key words: ATER, land-use efficiency, non-nodulating soybean isoline, nitrogen fertilization, spatial arrangement, interactions

Barley, Lentil, and Flax Yield under Different Intercropping Systems

AbstractIntercropping is being adopted as a method of crop production throughout the developing tropics. The objective of this experiment was to assess how the productivity of intercrops was affected by the interaction of irrigation levels and mulches, compared to monocrops. Six‐rowed barley (Hordeum vulgare L.) was intercropped with lentil (Lens culinaris Medik) and flax (Linum usitatissimum L.) with two levels of irrigations [(i) zero and (ii) one irrigation applied 35 d after planting] and two levels of mulch [(i) no mulch and (ii) rice straw mulch at the rate of approximately 7 Mg/ha−1]. Monocrop of each species were also grown. Seed yield of the monocrops were higher than their intercrop yields. Intercropped barley yielded 73 to 81% of the yield to monoculture. Intercropped lentil yielded 30 to 34% of the yield of monoculture, whereas intercropped seed yield of flax ranged from 27 to 31% of monoculture. Yield increased from one application of irrigation ranged from 12 to 21% of zero irrigation. The increase in yield due to straw mulch was 11 to 17% higher over no mulch. The barley‐lentil intercrop recorded higher values of land equivalent ratio (LER) and monetary advantage (MA), and had higher intercropping advantage of area time equivalent ratio (ATER) than the barley‐flax intercrop.

Productivity and risk evaluation in constrasting intercropping systems

Four contrasting intercropping systems, sorghum (Sorghum bicolor (L.) Moench)/pigeonpea (Cajanus cajan (L.) Millsp.), groundnut (Archis hypogaea L.)/pigeonpea, sorghum/pearl millet (Pennisetum americanum (L.) Leeke), and groundnut/pearl millet, were evaluated along with sole crops from 1979 to 1982, each year in nine different situations spread over different soil types and agronomic managements, with the objective of analysing the productivity and risk associated with these systems. Productivity of intercrops was closely related to the diversity of the crops involved. The two pigeonpea-based systems, with an interval of about 3 months between harvests of the crops, showed a large and consistent advantage over the respective sole crops. On the basis of land productivity, sorghum/pigeonpea averaged 49% and pigeonpea/groundnut 53% advantage over their respective sole-crop yields. In economic terms, these intercrops were also more profitable than the respective sole crops. The other two systems, with only 2–4 weeks' difference between harvests of the components, showed a much lower and less-consistent advantage. The groundnut/millet recorded 18% advantage and the sorghum/millet 7% over their respective sole crops. Risk was measured by calculating the probability of success or failure of intercrops in satisfying specified quantities of yields or income in comparison with an optimal shared sole system having some of both sole crops. Pigeonpea-based intercropping systems were less risky than shared (or optimal) sole crops over a wide range of expected yields or income. There was no advantage for the sorghum/millet intercropping compared with the shared sole crops at lower expectation, and for higher expectations sole sorghum should be preferred to the intercrop. Risk from groundnut/millet was less than from the shared sole system only in limited situations. Reduced risk of pigeonpea-based intercrops was associated with higher productivity and lower variability of combined intercrop yields or income. The methods employed in this study can be extended for risk evaluation in other intercropping and mixed systems.

Corn‐Peanut Intercrop Performance in Relation to Component Crop Relative Planting Dates

AbstractA two‐yr (1982 and 1983) field study was conducted to determine the vegetative and reproductive effects of three intercrop treatments on corn (Zea mays L.) SS 335 A hybrid and peanut (Arachis hypogaea L.) ‘Florunner’. Three planting time treatments of corn relative to peanut (2 or 3 wk before, simultaneous, and 2 or 3 wk after) were compared. Sole crops of each species were also established. Initial vegetative growth of peanut was greatest when intercropped with corn planted after peanut. Intercropped corn planted before peanut matured early but, after harvest, did not result in an environment favorable for peanut to compensate for early season growth reductions. Dry weights of intercropped peanut, regardless of relative time of corn planting, were reduced to half or less of those of sole‐crop peanut. Reproductive development of both species when intercropped was generally not affected by relative planting times. Grain yields of intercropped corn were 85 to 90% and 46 to 74% of sole‐crop yields in 1982 and 1983, respectively. Intercropped peanut yielded 33 to 37% and 47 to 49% of sole‐crop yield in 1982 and 1983, respectively. Land equivalent ratios for intercrop combinations were not significantly affected by relative planting times; they ranged from 1.20 to 1.25 and 0.96 to 1.26 in 1982 and 1983, respectively. Corn contributed 69 to 72% and 49 to 62% of total intercrop production in 1982 and 1983, respectively. The results suggest that greatest total productivity in a corn‐peanut intercrop will occur when corn is planted either simultaneously with or earlier than peanut. The highest intercrop peanut yields tended to occur when corn and peanut were planted simultaneously.

RE: Area‐X‐Time Equivalency Ratio: A Method for Evaluating the Productivity of Intercrops. C.K. Hiebsch and R.E. McCollum (Agron. J. 79:15–22, 1987)

Agronomy JournalVolume 79, Issue 5 p. 945-945 Letter to the Editor RE: Area-X-Time Equivalency Ratio: A Method for Evaluating the Productivity of Intercrops. C.K. Hiebsch and R.E. McCollum (Agron. J. 79:15–22, 1987) Chandra K. Reddy, Chandra K. Reddy Natural Resources and Environmental Studies, Alabama A&M Univ., Normal, ALSearch for more papers by this author Chandra K. Reddy, Chandra K. Reddy Natural Resources and Environmental Studies, Alabama A&M Univ., Normal, ALSearch for more papers by this author First published: 01 September 1987 https://doi.org/10.2134/agronj1987.00021962007900050039xCitations: 1AboutPDF 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 No abstract is available for this article.Citing Literature Volume79, Issue5September‐October 1987Pages 945-945 RelatedInformation

Area‐×‐Time Equivalency Ratio: A Method For Evaluating The Productivity Of Intercrops1

AbstractProduction systems involving interplanted food crops are widespread in tropical latitudes, and interest in quantifying the productive potential of intercrops is high. Published data often suggest a sizable gain in land‐use efficiency by growing such crops in mixtures. Our thesis is that many of the large intercrop advantages reported in the literature are misleading because the conceptual basis on which the monoculture‐vs.‐intercrop comparisons were made is incomplete. In this paper, we review the various methods for estimating intercrop productivity, propose a concept which we believe will remove the principal limitation in conventional methodology, and test the new concept with intercrop data from the literature. The land equivalency ratio (LER) is the most‐used convention for intercrop‐vs.‐monoculture comparisons, but LER is frequently inappropriate because cropping‐system duration, i.e., time, is not included in its calculation. Duration of land occupancy by an intercrop is often longer than production‐cycle duration for one or more of the interplanted species. We propose an area‐×‐time equivalency ratio (ATER) and suggest that it will correct this conceptual inadequacy in LER. When published intercrop data were reevaluated via the ATER concept, large land‐use advantages ascribed to growing food crops in mixtures disappeared. We conclude that most crop mixtures utilize land area and time (area·time) at about the same efficiency as pure stands of the mixture's components.

Empirical models of maize—sorghum intercrop production and agrotechnology transfer in Central America

To define the area for which an agricultural technology is suitable requires a knowledge of both the environmental factors which determine the production of that technology and how those factors vary geographically. Using data from multi-location experiments in Guatemala and El Salvador, multiple regression techniques were used to identify combinations of environmental variables which could predict the production of intercropped maize and sorghum. A ‘transfer analysis’, involving the comparison of regression-predicted yields with site-predicted yields, was used as a means of comparing the predictive ability of different models. We suggest that the development of such regression models provides a useful method of defining replicable production areas, resulting in an area classification based on the predicted production of specific technologies.