Polynomial functional models to simulate crop growth in maize (Zea mays L.) cultivars

• Published in: Journal of agronomy and crop science (1986) Vol. 171; no. 1; pp. 55 - 64
• Main Authors: Ramachandra Prasad, T.V. (University of Agricultural Sciences, Bangalore (India)), Krishnamurthy, K, Devendra, R, Kailasam, C
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.08.1993
• Subjects: APLICACION DE ABONOS; AZOTE; CRECIMIENTO; CROISSANCE; crop growth; CROP YIELD; dry matter production; FERTILISATION; FERTILIZER APPLICATION; GROWTH; heteroscedasticity; Maize; MODELE DE SIMULATION; MODELOS DE SIMULACION; NITROGEN; NITROGENO; PLANT POPULATION; POBLACION VEGETAL; polynomial exponentials; polynomials; POPULATION VEGETALE; relative growth rate; RENDEMENT DES CULTURES; RENDIMIENTO DE CULTIVOS; SIMULATION MODELS; VARIEDADES; VARIETE; VARIETIES; ZEA MAYS
• ISSN: 0931-2250; 1439-037X
• DOI: 10.1111/j.1439-037X.1993.tb00436.x

Polynomial and polynomial exponential models of order one to four were tried to describe crop growth in two maize cultivars viz., Deccan hybrid and Deccan 101 of an agronomic trial conducted at the University of Agricultural Sciences, Bangalore, on alfisols. Relative growth rate (RGR) of classical and functional methods was compared. Models performance was assessed based on r2, χ2 residuals sum of squares (RSS), root mean standard deviation (RMSD) and presence or absence of heteroscedasticity in models' predictions. In the cultivars, polynomials of order three and four in Deccan hybrid and cubic polynomial in Deccan 101 simulated dry matter production (DMP) by 99.5 % and showed good distribution of error variance over the observed DMP. The RGR from the third and fourth degree polynomials in both the cultivars was comparable to the classical method and explained better during post‐silking period. Polynomial exponentials predicted very low RGR. Between cultivars, Deccan 101 showed higher RGR during 45–80 days after sowing and contributed significantly more to final DMP.