Allometric Relationships of Plant Height and Vegetative Traits in Wheat (Triticum Astivum) Cultivars at Different Growth Stages

Abstract

Determining the allometric relationship between plant height and plant morphological traits is vital for predicting the production in simulation models. An experiment was conducted in the crop year of 2013-2014 to identify the allometric relationships of the plant height with other vegetative traits in wheat. It was conducted as a factorial experiment in a randomized complete block design with three replications. The first factor consisted of two wheat cultivars, including stress-tolerant Sirvan cultivar and stress-sensitive Sivand cultivar. Sampling was performed in three growth stages (rosette, tillering, and flowering) in the wheat crop and the vegetative traits of leaf area, dry weight of vegetative parts (stem and leaf), and plant height, number of the leaves per wheat at the different stages of growth were measured. Linear equation fit (lny = a + b lnx1 + cx2) was performed for different growth stages. In this equation, y was considered as a dependent variable of plant height and x was considered as the measured traits. The research results showed that the irrigation conditions and an interaction effect of the cultivar had no significant effect on the investigated traits. Thus, an equation could well justify the relationships between the leaf area and the height and other traits in the two cultivars in both irrigation conditions. However, there was a significant difference between the cultivars, so it was defined as an independent factor in the equation. The coefficients of explanation for the relationship between the stem height and number of plants, stem dry weight, and total dry weight of vegetative parts were higher than 0.87, indicating a high correlation between the vegetative traits and the stem height in both plants and field environment. Since the allometric relationships are stable in a species, these relationships can be used to determine the vegetative process of species, and the obtained equations can be used in the wheat simulation models to estimate the leaf area and the height quickly and easily.