Growth Analysis of Quinoa (Chenopodium quinoa Willd.) in Response to Fertilization and Soil Tillage.

Growth analysis is an appropriate method for plant response to various environmental and cultural conditions during plant life. A 2-year experiment was conducted to evaluate the effect of soil tillage and fertilization on the growth and growth parameters of quinoa crop and to determine the association between yield and growth characteristics at both the single plant and crop stand level. The experiment was laid out in a split-plot design with two replicates, two main plots [conventional (CT) and minimum tillage (MT)] and four sub-plots [fertilization treatments: untreated, inorganic fertilization of 100 (N1) and 200 kg N ha-1 (N2) and sheep manure]. The highest absolute growth rate (AGR) and crop growth rate (CGR) values were recorded between the middle of vegetative growth stage and the beginning of anthesis (50-75 DAS) under conventional tillage coupled with manure (AGR: 0.4577 g day-1, CGR: 11.44 g m-2 day-1) and with N2 treatment (AGR: 0.4521 g day-1, CGR: 11.31 g m-2 day-1). Concerning specific leaf area (SLA), the highest value (150.58 cm² g-1) was found at 75 DAS in N2 treatment. Leaf area index (LAI) were positively affected by soil tillage and fertilization with greatest values found under conventional tillage coupled with N2 treatment (5.110 m² m-2). The highest seed yield was observed in N2 treatment (2488 and 2388 kg ha-1 under CT and MT, respectively). As a conclusion, the cultivation under conventional tillage and the increasing levels of applied nitrogen up to 200 kg N ha-1 increases crop growth and yield. [ABSTRACT FROM AUTHOR]