Skip to main content

Advertisement

Log in

Intercropping indices evaluation on grain legume-small grain cereals mixture: a critical meta-analysis review

  • Review Article
  • Published:
Agronomy for Sustainable Development Aims and scope Submit manuscript

Abstract

Intercropping is a mature and well-known agronomic practice that began to attract interest from the scientific community in the mid-1900s and has known an exponential growth in research activity since the beginning of this century. Over the years, different intercropping indices have been developed to evaluate the performance of this crop production system in comparison to standard monoculture practices. Nowadays, more than 20 of these intercropping indices have been described in scientific literature. This review aims to review these indices and check their performance using a meta-dataset consisting of data points from various intercropping experiments that have been described in peer-reviewed publications. Our results show that different indices evaluate different aspects of intercropping trials and that commonly used indices generally do not capture the full performance of the system. More specifically, intercropping results are influenced by both the total sowing density and the crop ratio and indices differ in the way that these dependencies are accounted for. This study suggests creating a standard protocol for the intercropping trials and their evaluation as crucial elements to optimize intercropping research.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9

Similar content being viewed by others

Availability of data and materials

The datasets generated during the current study will be made publicly available in the ZENODO repository, upon acceptance for publication.

Code availability

Not applicable.

References

  • Adah OC, Enemali IA, Adejoh SO, Edoka MH (2015) Mathematics applications for agricultural development: Implications for agricultural extension delivery. J Nat Sci Ext Del 5:20

    Google Scholar 

  • Adetiloye P, Ezedinma F, Okigbo B (1983) A land equivalent coefficient (lec) concept for the evaluation of competitive and productive interactions in simple to complex crop mixtures. Ecol Modell 19(1):27–39. https://doi.org/10.1016/0304-3800(83)90068-6

    Article  Google Scholar 

  • Afe A, Atanda S et al (2015) Percentage yield difference, an index for evaluating intercropping efficiency. Am J Exp Agric 5(5):278–291. https://doi.org/10.9734/AJEA/2015/12405

    Article  Google Scholar 

  • Agegnehu G, Ghizaw A, Sinebo W (2006) Yield performance and land-use efficiency of barley and faba bean mixed cropping in ethiopian highlands. Eur J Agron 25(3):202–207. https://doi.org/10.1016/j.eja.2006.05.002

    Article  Google Scholar 

  • Ajal J, Jäck O, Vico G, Weih M (2021) Functional trait space in cereals and legumes grown in pure and mixed cultures is influenced more by cultivar identity than crop mixing. Perspect Plant Ecol Evol Syst 50:125612. https://doi.org/10.1016/j.ppees.2021.125612

  • Ajal J, Kiær LP, Pakeman RJ, Scherber C, Weih M (2022) Intercropping drives plant phenotypic plasticity and changes in functional trait space. Basic Appl Ecol 61:41–52

    Article  Google Scholar 

  • Annicchiarico P, Alami IT, Abbas K, Pecetti L, Melis R, Porqueddu C (2017) Performance of legume-based annual forage crops in three semi-arid mediterranean environments. Crop Pasture Sci 68(11):932–941. https://doi.org/10.1071/CP17068

    Article  Google Scholar 

  • Annicchiarico P, Collins RP, De Ron AM, Firmat C, Litrico I, Hauggaard-Nielsen H (2019) Do we need specific breeding for legume-based mixtures? Adv Agron 157:141–215. https://doi.org/10.1016/bs.agron.2019.04.001

    Article  Google Scholar 

  • Banik P (1996) Evaluation of wheat (triticum aestivum) and legume intercropping under 1: 1 and 2: 1 row-replacement series system. J Agron Crop Sci 176(5):289–294. https://doi.org/10.1111/j.1439-037X.1996.tb00473.x

    Article  Google Scholar 

  • Barker S, Dennett M (2013) Effect of density, cultivar and irrigation on spring sown monocrops and intercrops of wheat (triticum aestivum l.) and faba beans (vicia faba l.). Eur J Agron 51:108–116. https://doi.org/10.1016/j.eja.2013.08.001

    Article  Google Scholar 

  • Baxevanos D, Tsialtas IT, Vlachostergios DN, Hadjigeorgiou I, Dordas C, Lithourgidis A (2017) Cultivar competitiveness in pea-oat intercrops under mediterranean conditions. Field Crops Res 214:94–103. https://doi.org/10.1016/j.fcr.2017.08.024

    Article  Google Scholar 

  • Bedoussac L, Journet EP, Hauggaard-Nielsen H, Naudin C, Corre-Hellou G, Jensen ES, Prieur L, Justes E (2015) Ecological principles underlying the increase of productivity achieved by cereal-grain legume intercrops in organic farming. a review. Agron Sustain Dev 35:911–935

    Article  Google Scholar 

  • Bedoussac L, Justes E (2008) The efficiency of durum wheat and winter pea intercropping to increase wheat grain protein content depends on nitrogen availability and wheat cultivar

  • Bedoussac L, Justes E (2011) A comparison of commonly used indices for evaluating species interactions and intercrop efficiency: Application to durum wheat-winter pea intercrops. Field Crops Res 124(1):25–36. https://doi.org/10.1016/j.fcr.2011.05.025

    Article  Google Scholar 

  • Bonnet C, Gaudio N, Alletto L, Raffaillac D, Bergez JE, Debaeke P, Gavaland A, Willaume M, Bedoussac L, Justes E (2021) Design and multicriteria assessment of low-input cropping systems based on plant diversification in southwestern france. Agron Sustain Dev 41:1–19

    Google Scholar 

  • Brooker RW, Bennett AE, Cong WF, Daniell TJ, George TS, Hallett PD, Hawes C, Iannetta PP, Jones HG, Karley AJ et al (2015) Improving intercropping: a synthesis of research in agronomy, plant physiology and ecology. New Phytol 206(1):107–117. https://doi.org/10.1111/nph.13132

    Article  PubMed  Google Scholar 

  • Bulson H, Snaydon R, Stopes C (1997) Effects of plant density on intercropped wheat and field beans in an organic farming system. J Agric Sci 128(1):59–71. https://doi.org/10.1017/S0021859696003759

    Article  Google Scholar 

  • Bybee-Finley KA, Ryan MR (2018) Advancing intercropping research and practices in industrialized agricultural landscapes. Agriculture 8(6):80. https://doi.org/10.3390/agriculture8060080

    Article  Google Scholar 

  • Chapagain T, Riseman A (2015) Nitrogen and carbon transformations, water use efficiency and ecosystem productivity in monocultures and wheat-bean intercropping systems. Nutr Cycl Agroecosystems 101:107–121. https://doi.org/10.1007/s10705-014-9647-4

    Article  CAS  Google Scholar 

  • De Wit C, Van den Bergh J (1965) Competition between herbage plants. The Journal of Agricultural Science 13:212–221. https://doi.org/10.18174/njas.v13i2.17501

    Article  Google Scholar 

  • De Wit CT (1960) On competition. Centrum voor Landbouwpublikaties en Landbouwdocumentatie

  • Dekker J, Meggitt W, Putnam AR (1983) Experimental methodologies to evaluate allelopathic plant interactions: The abutilon theophrasti-glycine max model. J Chem Ecol 9:945–981. https://doi.org/10.1007/BF00982204

    Article  CAS  PubMed  Google Scholar 

  • Demie DT, Döring TF, Finckh MR, Van Der Werf W, Enjalbert J, Seidel SJ (2022) Mixture\(\times \) genotype effects in cereal/legume intercropping. Frontiers in Plant Sci 13

  • Dhima K, Vasilakoglou I, Keco RX, Dima A, Paschalidis K, Gatsis T (2014) Forage yield and competition indices of faba bean intercropped with oat. Grass Forage Sci 69(2):376–383

    Article  CAS  Google Scholar 

  • Duc G, Agrama H, Bao S, Berger J, Bourion V, De Ron AM, Gowda CL, Mikic A, Millot D, Singh KB et al (2015) Breeding annual grain legumes for sustainable agriculture: new methods to approach complex traits and target new cultivar ideotypes. Crit Rev Plant Sci 34(1–3):381–411. https://doi.org/10.1080/07352689.2014.898469

    Article  Google Scholar 

  • Eskandari H, Ghanbari A (2010) Effect of different planting pattern of wheat (triticum aestivum) and bean (vicia faba) on grain yield, dry matter production and weed biomass. Not Sci Biol 2(4):111–115

    Article  Google Scholar 

  • Feng C, Sun Z, Zhang L, Feng L, Zheng J, Bai W, Gu C, Wang Q, Xu Z, van der Werf W (2021) Maize/peanut intercropping increases land productivity: A meta-analysis. Field Crops Res 270:108208. https://doi.org/10.1016/j.fcr.2021.108208

    Article  Google Scholar 

  • Firbank L, Watkinson A (1985) On the analysis of competition within two-species mixtures of plants. J Appl Ecol 503–517. https://doi.org/10.2307/2403181

  • Fujita K, Ofosu-Budu K, Ogata S (1992) Biological nitrogen fixation in mixed legume-cereal cropping systems. Plant Soil 141:155–175

    Article  CAS  Google Scholar 

  • Gitari HI, Nyawade SO, Kamau S, Karanja NN, Gachene CK, Raza MA, Maitra S, Schulte-Geldermann E (2020) Revisiting intercropping indices with respect to potato-legume intercropping systems. Field Crops Res 258:107957. https://doi.org/10.1016/j.fcr.2020.107957

    Article  Google Scholar 

  • Gooding M, Kasyanova E, Ruske R, Hauggaard-Nielsen H, Jensen ES, Dahlmann C, Von Fragstein P, Dibet A, Corre-Hellou G, Crozat Y et al (2007) Intercropping with pulses to concentrate nitrogen and sulphur in wheat. J Agric Sci 145(5):469–479. https://doi.org/10.1017/S0021859607007241

    Article  CAS  Google Scholar 

  • Grace JB (1995) On the measurement of plant competition intensity. Ecology 76(1):305–308. https://doi.org/10.2307/1940651

    Article  Google Scholar 

  • Harris D, Natarajan M, Willey R (1987) Physiological basis for yield advantage in a sorghum/groundnut intercrop exposed to drought. 1. dry-matter production, yield, and light interception. Field Crops Res 17(3–4):259–272. https://doi.org/10.1016/0378-4290(87)90039-6

    Article  Google Scholar 

  • Haug B, Messmer MM, Enjalbert J, Goldringer I, Forst E, Flutre T, Mary-Huard T, Hohmann P (2021) Advances in breeding for mixed cropping-incomplete factorials and the producer/associate concept. Front Plant Sci 11:620400. https://doi.org/10.3389/fpls.2020.620400

    Article  PubMed Central  PubMed  Google Scholar 

  • Hauggaard-Nielsen H, Andersen MK, Joernsgaard B, Jensen ES (2006) Density and relative frequency effects on competitive interactions and resource use in pea-barley intercrops. Field Crops Res 95(2–3):256–267. https://doi.org/10.1016/j.fcr.2005.03.003

    Article  Google Scholar 

  • Hauggaard-Nielsen H, Jensen ES (2001) Evaluating pea and barley cultivars for complementarity in intercropping at different levels of soil n availability. Field Crops Res 72(3):185–196. https://doi.org/10.1016/S0378-4290(01)00176-9

    Article  Google Scholar 

  • Homulle Z, George TS, Karley AJ (2021) Root traits with team benefits: understanding belowground interactions in intercropping systems. Plant Soil 1–26. https://doi.org/10.1007/s11104-021-05165-8

  • Jensen ES, Chongtham IR, Dhamala NR, Rodriguez C, Carton N, Carlsson G (2020) Diversifying european agricultural systems by intercropping grain legumes and cereals. Cienc Investig Agrar: Rev Latinoamericana Cienc Agric 47(3):174–186. https://doi.org/10.7764/ijanr.v47i3.2241

    Article  Google Scholar 

  • Justes E, Bedoussac L, Dordas C, Frak E, Louarn G, Boudsocq S, Journet EP, Lithourgidis A, Pankou C, Zhang C et al (2021) The 4c approach as a way to understand species interactions determining intercropping productivity. Front Agric Sci Eng 8(3):3

    Google Scholar 

  • Khanal U, Stott KJ, Armstrong R, Nuttall JG, Henry F, Christy BP, Mitchell M, Riffkin PA, Wallace AJ, McCaskill M et al (2021) Intercropping-evaluating the advantages to broadacre systems. Agriculture 11(5):453. https://doi.org/10.3390/agriculture11050453

    Article  Google Scholar 

  • Li C, Hoffland E, Kuyper TW, Yu Y, Li H, Zhang C, Zhang F, van der Werf W (2020) Yield gain, complementarity and competitive dominance in intercropping in china: A meta-analysis of drivers of yield gain using additive partitioning. Eur J Agron 113:125987

    Article  CAS  Google Scholar 

  • Li L, Sun J, Zhang F, Li X, Yang S, Rengel Z (2001) Wheat/maize or wheat/soybean strip intercropping: I. yield advantage and interspecific interactions on nutrients. Field Crops Res 71(2):123–137. https://doi.org/10.1016/S0378-4290(01)00156-3

    Article  Google Scholar 

  • Li L, Tilman D, Lambers H, Zhang FS (2014) Plant diversity and overyielding: insights from belowground facilitation of intercropping in agriculture. New Phytol 203(1):63–69. https://doi.org/10.1111/nph.12778

    Article  CAS  PubMed  Google Scholar 

  • Li L, Zhang L, Zhang F (2013) Crop mixtures and the mechanisms of overyielding. Encyclopedia of Biodiversity 2:82–395

  • Li XF, Wang ZG, Bao XG, Sun JH, Yang SC, Wang P, Wang CB, Wu JP, Liu XR, Tian XL et al (2021) Long-term increased grain yield and soil fertility from intercropping. Nat Sustain 4(11):943–950

    Article  Google Scholar 

  • Lithourgidis A, Dordas C, Damalas CA, Vlachostergios D (2011) Annual intercrops: an alternative pathway for sustainable agriculture. Aust J Crop Sci 5(4):396–410

    Google Scholar 

  • Lithourgidis A, Vlachostergios D, Dordas C, Damalas C (2011) Dry matter yield, nitrogen content, and competition in pea-cereal intercropping systems. Eur J Agron 34(4):287–294. https://doi.org/10.1016/j.eja.2011.02.007

    Article  Google Scholar 

  • Loreau M, Hector A (2001) Partitioning selection and complementarity in biodiversity experiments. Nature 412(6842):72–76. https://doi.org/10.1038/35083573

    Article  CAS  ADS  PubMed  Google Scholar 

  • Lv W, Zhao X, Wu P, Lv J, He H (2021) A scientometric analysis of worldwide intercropping research based on web of science database between 1992 and 2020. Sustainability 13(5):2430. https://doi.org/10.3390/su13052430

    Article  Google Scholar 

  • Mamine F, Farès M (2020) Barriers and levers to developing wheat-pea intercropping in europe: A review. Sustainability 12(17):6962. https://doi.org/10.3390/su12176962

    Article  CAS  Google Scholar 

  • Martin-Guay MO, Paquette A, Dupras J, Rivest D (2018) The new green revolution: sustainable intensification of agriculture by intercropping. Sci Total Environ 615:767–772. https://doi.org/10.1016/j.scitotenv.2017.10.024

    Article  CAS  ADS  PubMed  Google Scholar 

  • Mead R, Willey R (1980) The concept of a ‘land equivalent ratio’and advantages in yields from intercropping. Exp Agric 16(3):217–228. https://doi.org/10.1017/S0014479700010978

    Article  Google Scholar 

  • Monti M, Pellicanò A, Santonoceto C, Preiti G, Pristeri A (2016) Yield components and nitrogen use in cereal-pea intercrops in mediterranean environment. Field Crops Res 196:379–388. https://doi.org/10.1016/j.fcr.2016.07.017

    Article  Google Scholar 

  • Morris R, Garrity D (1993) Resource capture and utilization in intercropping: water. Field Crops Res 34(3–4):303–317

    Article  Google Scholar 

  • Mousavi SR, Eskandari H (2011) A general overview on intercropping and its advantages in sustainable agriculture. J Appl Environ Biol Sci 1(11):482–486

    Google Scholar 

  • Moutier N, Baranger A, Fall S, Hanocq E, Marget P, Floriot M, Gauffreteau A (2022) Mixing ability of intercropped wheat varieties: stability across environments and tester legume species. Front Plant Sci 13:1495

    Article  Google Scholar 

  • Odo P (1991) Evaluation of short and tall sorghum varieties in mixtures with cowpea in the sudan savanna of nigeria: land equivalent ratio, grain yield and system productivity index. Exp Agric 27(4):435–441. https://doi.org/10.1017/S0014479700019426

    Article  Google Scholar 

  • Oyejola B, Mead R (1982) Statistical assessment of different ways of calculating land equivalent ratios (ler). Exp Agric 18(2):125–138. https://doi.org/10.1017/S0014479700013600

    Article  Google Scholar 

  • Pankou C, Lithourgidis A, Dordas C (2021) Effect of irrigation on intercropping systems of wheat (triticum aestivum l.) with pea (pisum sativum l.). Agronomy 11(2):283. https://doi.org/10.3390/agronomy11020283

    Article  CAS  Google Scholar 

  • Pankou C, Lithourgidis A, Dordas C (2021) Interaction of cultivar and irrigation on mixtures of wheat (triticum aestivum l.) with pea (pisum sativum l.). Not Bot Horti Agrobot Cluj Napoca 49(4):1–2. https://doi.org/10.15835/nbha49412488

    Article  Google Scholar 

  • Paynel F, Lesuffleur F, Bigot J, Diquélou S, Cliquet JB (2008) A study of 15n transfer between legumes and grasses. Agron Sustain Dev 28(2):281–290

    Article  CAS  Google Scholar 

  • Pelzer E, Hombert N, Jeuffroy MH, Makowski D (2014) Meta-analysis of the effect of nitrogen fertilization on annual cereal-legume intercrop production. Agron J 106(5):1775–1786. https://doi.org/10.2134/agronj13.0590

    Article  Google Scholar 

  • Preissel S, Reckling M, Schläfke N, Zander P (2015) Magnitude and farm-economic value of grain legume pre-crop benefits in europe: A review. Field Crops Res 175:64–79

    Article  Google Scholar 

  • Price GR et al (1970) Selection and covariance. Nature 227:520–521

    Article  CAS  ADS  PubMed  Google Scholar 

  • R Core Team (2021) R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing, Vienna, Austria

    Google Scholar 

  • Rao M, Willey R (1980) Preliminary studies of intercropping combinations based on pigeonpea or sorghum. Exp Agric 16(1):29–39. https://doi.org/10.1017/S001447970001067X

    Article  CAS  Google Scholar 

  • Raseduzzaman M, Jensen ES (2017) Does intercropping enhance yield stability in arable crop production? a meta-analysis. Eur J Agron 91:25–33

    Article  Google Scholar 

  • Ren Y, Liu J, Wang Z, Zhang S (2016) Planting density and sowing proportions of maize-soybean intercrops affected competitive interactions and water-use efficiencies on the loess plateau, china. Eur J Agron 72:70–79

    Article  Google Scholar 

  • Rodriguez C, Carlsson G, Englund JE, Flöhr A, Pelzer E, Jeuffroy MH, Makowski D, Jensen ES (2020) Grain legume-cereal intercropping enhances the use of soil-derived and biologically fixed nitrogen in temperate agroecosystems. a meta-analysis. European Journal of Agronomy 118:126077

    Article  CAS  Google Scholar 

  • Rohatgi A (2022) Webplotdigitizer: Version 4.6

  • Sainju UM (2017) Determination of nitrogen balance in agroecosystems. MethodsX 4:199–208

    Article  PubMed Central  PubMed  Google Scholar 

  • Selosse MA, Richard F, He X, Simard SW (2006) Mycorrhizal networks: des liaisons dangereuses? Trends Ecol Evol 21(11):621–628

    Article  PubMed  Google Scholar 

  • Shtaya MJ, Emeran AA, Fernández-Aparicio M, Qaoud HA, Abdallah J, Rubiales D (2021) Effects of crop mixtures on rust development on faba bean grown in mediterranean climates. Crop Prot 146:105686. https://doi.org/10.1016/j.cropro.2021.105686

    Article  Google Scholar 

  • Sinclair TR, Vadez V (2012) The future of grain legumes in cropping systems. Crop Pasture Sci 63(6):501–512

    Article  Google Scholar 

  • Snaydon R (1991) Replacement or additive designs for competition studies? J Appl Ecol 930–946. https://doi.org/10.2307/2404218

  • Snaydon R, Satorre E (1989) Bivariate diagrams for plant competition data: modifications and interpretation. J Appl Ecol 1043–1057. https://doi.org/10.2307/2403711

  • Sobkowicz P, Śniady R (2004) Nitrogen uptake and its efficiency in triticale (triticosecale witt.)-field beans (vicia faba var. minor l.) intercrop. Plant Soil Environ 50(11):500–506. https://doi.org/10.17221/4065-PSE

    Article  Google Scholar 

  • Streit J, Meinen C, Nelson WCD, Siebrecht-Schöll DJ, Rauber R (2019) Above-and belowground biomass in a mixed cropping system with eight novel winter faba bean genotypes and winter wheat using ftir spectroscopy for root species discrimination. Plant Soil 436:141–158. https://doi.org/10.1007/s11104-018-03904-y

    Article  CAS  Google Scholar 

  • Tilman D (2020) Benefits of intensive agricultural intercropping. Nat Plants 6(6):604–605

    Article  PubMed  Google Scholar 

  • Tsialtas IT, Baxevanos D, Vlachostergios DN, Dordas C, Lithourgidis A (2018) Cultivar complementarity for symbiotic nitrogen fixation and water use efficiency in pea-oat intercrops and its effect on forage yield and quality. Field Crops Res 226:28–37

    Article  Google Scholar 

  • Van Der Heijden MG, Horton TR (2009) Socialism in soil? the importance of mycorrhizal fungal networks for facilitation in natural ecosystems. J Ecol 97(6):1139–1150

    Article  Google Scholar 

  • van der Werf W, Zhang L, Li C, Chen P, Feng C, Xu Z, Zhang C, Gu C, Bastiaans L, Makowski D et al (2021) Comparing performance of crop species mixtures and pure stands. Front Agricult Sci Eng 8:481–489. https://doi.org/10.15302/J-FASE-2021413

  • Watson CA, Reckling M, Preissel S, Bachinger J, Bergkvist G, Kuhlman T, Lindström K, Nemecek T, Topp CF, Vanhatalo A et al (2017) Grain legume production and use in european agricultural systems. Adv Agron 144:235–303

    Article  Google Scholar 

  • Weigelt A, Jolliffe P (2003) Indices of plant competition. J Ecol 707–720

  • Wezel A, Soboksa G, McClelland S, Delespesse F, Boissau A (2015) The blurred boundaries of ecological, sustainable, and agroecological intensification: a review. Agron Sustain Dev 35:1283–1295. https://doi.org/10.1007/s13593-015-0333-y

    Article  Google Scholar 

  • Wickham H (2016) ggplot2: Elegant Graphics for Data Analysis. Springer-Verlag, New York

    Book  Google Scholar 

  • Willey R (1985) Evaluation and presentation of intercropping advantages. Exp Agric 21(2):119–133. https://doi.org/10.1017/S0014479700012400

    Article  Google Scholar 

  • Willey R, Rao M (1980) A competitive ratio for quantifying competition between intercrops. Exp Agric 16(2):117–125

    Article  Google Scholar 

  • Williams AC, McCarthy BC (2001) A new index of interspecific competition for replacement and additive designs. Ecol Res 16:29–40. https://doi.org/10.1046/j.1440-1703.2001.00368.x

    Article  Google Scholar 

  • Wilson JB (1988) Shoot competition and root competition. J Appl Ecol 279–296. https://doi.org/10.2307/2403626

  • Xu Z, Li C, Zhang C, Yu Y, van der Werf W, Zhang F (2020) Intercropping maize and soybean increases efficiency of land and fertilizer nitrogen use; a meta-analysis. Field Crops Res 246:107661

    Article  Google Scholar 

  • Yu Y (2016) Crop yields in intercropping: meta-analysis and virtual plant modelling. Ph. D. thesis, Wageningen University and Research

Download references

Funding

This study is part of the CROPDIVA project “Climate Resilient Orphan croPs for increased DIVersity in Agriculture” funded by the EU’s Horizon 2020 Research and Innovation Program (Grant 364 Agreement No. 101000847).

Author information

Authors and Affiliations

Authors

Contributions

Conceptualization: R.Z.; writing—original draft preparation: R.Z.; writing—review and editing: S.L., G.V., K.D., R.D., S.M., and G.H.; formal analysis: S.L., R.Z, and S.M.; visualization: R.Z., S.L., and S.M. All authors have read and agreed to the published version of the manuscript.

Corresponding author

Correspondence to Riccardo Zustovi.

Ethics declarations

Ethics approval

Not applicable.

Consent to participate

Not applicable.

Consent for publication

Not applicable.

Conflict of interest

The authors declare no competing interests.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Appendix: Mathematical proof

Appendix: Mathematical proof

Here are listed the mathematical proofs of the simplifications in Table 2 of PYD, CI, NER, RCI, CB, and CC.

The simplification is done only for one of the two partial indices.

The formula of PYD

$$\begin{aligned} \begin{aligned} \text {PYD}&= 100 -[(\frac{y^{\text {c}}-y^{\text {ci}}}{y^{\text {c}}} + \frac{y^{\text {c}}-y^{\text {li}}}{y^{\text {c}}}) 100] \\&= 100 -[(\frac{y^{\text {c}}}{y^{\text {c}}} -\frac{y^{\text {ci}}}{y^{\text {c}} } +\frac{y^{\text {c}}}{y^{\text {c}}} - \frac{y^{\text {li}}}{y^{\text {c}}}) 100] \\&= 100 -[(1 -\text {LER}^{\text {c}} + 1 - \text {LER}^{\text {c}}) 100] \\&= 100 -[ (2- \text {LER}) 100] \\&= 100 -[200 - 100 \text {LER}] \\&= 100 -200 + 100 \text {LER} \\&= 100 (\text {LER} - 1) \end{aligned} \end{aligned}$$

The formula of CI

$$\begin{aligned} \text {CI}= & {} \frac{p^{\text {c}} y^{\text {c}} + p^{\text {c}} y^{\text {c}}}{y^{\text {ci}}+y^{\text {li}}} - 1 \\= & {} \frac{(z^{\text {ci}} / z^{\text {tot}}) y^{\text {c}} + (z^{\text {li}} / z^{\text {tot}}) y^{\text {c}}}{y^{\text {ci}}+y^{\text {li}}} - 1 \\= & {} z^{\text {tot}} \frac{z^{\text {ci}} y^{\text {c}} + z^{\text {li}} y^{\text {c}}}{y^{\text {ci}}+y^{\text {li}}} - 1 \\= & {} z^{\text {tot}} \frac{1}{\text {YR}} - 1 \\= & {} \frac{z^{\text {tot}}}{\text {YR}} - 1 \end{aligned}$$

The formula of NER is

$$\begin{aligned} \begin{aligned} \text {NER}^{\text {c}}&= \frac{y^{\text {ci}}}{p^{\text {c}} y^{\text {c}}}\\&= \frac{y^{\text {ci}}}{\frac{z^{\text {ci}}}{z^{\text {tot}}} y^{\text {c}}}\\&= \frac{y^{\text {ci}}}{z^{\text {ci}}y^{\text {c}}} z^{\text {tot}}\\&= \text {CPR}^{\text {c}} z^{\text {tot}} \end{aligned} \end{aligned}$$

The formula of RCI is

$$\begin{aligned} \begin{aligned} \text {RCI}^{\text {c}}&= \frac{p^{\text {c}} y^{\text {c}} - y^{\text {ci}}}{p^{\text {c}} y^{\text {c}}} \\&= \frac{p^{\text {c}} y^{\text {c}}}{p^{\text {c}} y^{\text {c}}} - \frac{y^{\text {ci}}}{p^{\text {c}} y^{\text {c}}} \\&= 1 - \frac{y^{\text {ci}}}{\frac{z^{\text {ci}}}{z^{\text {tot}}} y^{\text {c}}}\\&= 1 - \frac{y^{\text {ci}}}{z^{\text {ci}} y^{\text {c}}} z^{\text {tot}}\\&= 1 - \text {CPR}^{\text {c}} z^{\text {tot}}\\&= 1 - \text {NER}^{\text {c}} \end{aligned} \end{aligned}$$

The formula of CB is

$$\begin{aligned} \text {CB}^{\text {c}}= & {} \ln \frac{(z^{\text {li}} y^{\text {ci}}) / (z^{\text {ci}} y^{\text {li}})}{y^{\text {c}} / y^{\text {c}}} \\= & {} \ln (\frac{z^{\text {li}} y^{\text {ci}}}{z^{\text {ci}} y^{\text {li}}} / \frac{y^{\text {c}}}{y^{\text {c}}})\\= & {} \ln (\frac{z^{\text {li}} y^{\text {ci}}}{z^{\text {ci}} y^{\text {li}}} \frac{y^{\text {c}}}{y^{\text {c}}})\\= & {} \ln (\frac{z^{\text {li}} y^{\text {l}} y^{\text {ci}}}{z^{\text {ci}} y^{\text {c}} y^{\text {li}}})\\= & {} \ln (\text {CPR}^{\text {c}} \frac{1}{\text {CPR}^{\text {c}}})\\= & {} \ln \frac{\text {CPR}^{\text {c}}}{\text {CPR}^{\text {c}}} \end{aligned}$$

The formula of CC is

$$\begin{aligned} \text {CC}^{\text {c}}= & {} (\frac{y^{\text {ci}}}{y^{\text {ci}}+y^{\text {li}}} / \frac{p^{\text {c}} y^{\text {c}}}{p^{\text {c}} y^{\text {c}} + p^{\text {l}} y^{\text {l}}}) - 1 \\= & {} (\frac{y^{\text {ci}}}{y^{\text {ci}}+y^{\text {li}}} / \frac{\frac{z^{\text {ci}}}{z^{\text {tot}}} y^{\text {c}}}{\frac{z^{\text {ci}}}{z^{\text {tot}}} y^{\text {c}} + \frac{z^{\text {li}}}{z^{\text {tot}}} y^{\text {c}}}) - 1 \\= & {} (\frac{y^{\text {ci}}}{y^{\text {ci}}+y^{\text {li}}} \frac{\frac{1}{z^{\text {tot}}}(z^{\text {ci}} y^{\text {c}} + z^{\text {li}} y^{\text {c}})}{\frac{1}{z^{\text {tot}}}(z^{\text {ci}} y^{\text {c}})}) - 1 \\= & {} (y^{\text {ci}} \frac{1}{y^{\text {ci}}+y^{\text {li}}} (z^{\text {ci}} y^{\text {c}} + z^{\text {li}} y^{\text {c}}) \frac{1}{(z^{\text {ci}} y^{\text {c}})}) - 1 \\= & {} (\frac{y^{\text {ci}}}{z^{\text {ci}} y^{\text {c}}} \frac{z^{\text {ci}} y^{\text {c}} + z^{\text {li}} y^{\text {c}}}{y^{\text {ci}}+y^{\text {li}}}) - 1 \\= & {} (\text {CPR}^{\text {c}} \frac{1}{\text {YR}}) - 1\\= & {} (\frac{\text {CPR}^{\text {c}}}{\text {YR}}) - 1 \end{aligned}$$

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Zustovi, R., Landschoot, S., Dewitte, K. et al. Intercropping indices evaluation on grain legume-small grain cereals mixture: a critical meta-analysis review. Agron. Sustain. Dev. 44, 5 (2024). https://doi.org/10.1007/s13593-023-00934-4

Download citation

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s13593-023-00934-4

Keywords

Navigation