Effect of zeolite on the micro-morphological and biochemical features of the spring rapeseed (Brassica napus L.)

Abstract

The study aimed to assess the effect of a natural mineral fertilizer – zeolite on the micro-morphological and biochemical characteristics of the spring rapeseed Brassica napus L. cv. ―Rif‖ ). Experiments were held at the Federal Research Center for Breeding, Agro-technics and Nursery Horticulture, Moscow, and Agro-industrial Institute, Bunin Yelets State University, Yelets, Russia from 2018 to 2020. The study scheme comprises four treatments as follows: a. control (no fertilizer), b. NPK @ 60-60-60 kg ha-1, c. Zeolite 5 t ha-1, and d. NPK @ 60-60-60 kg ha-1 + Zeolite 5 t ha-1. Results revealed that the maximum number of stomata was observed in the rapeseed crop treated with natural and mineral fertilizer – zeolite. On average, there were 537 pcs/mm2 on the adaxial surface, and 480 pcs/mm2 on the abaxial leaf surfaces. The mineral fertilizer application only, and in combination with a natural ameliorant, contributed an increase in photosynthetic pigments, which was about 22% more relative to the control. To determine the content of trace elements (Mn, Fe, Zn, and Ni) according to the phases of spring rapeseed development, the trace elements were decreased by the harvesting phase. The only exception was Co, where content was increased by the time of rapeseed ripening. The accumulation of the studied trace elements in spring rapeseed plants at maturity can be represented by the following decreasing series, Fe>Mn>Zn>Cu>Ni>Co. The correlation coefficients also revealed that there was a strong relationship among all the studied elements. A high correlation (r = 0.95) was found between the seed yield and the magnitude of the photosynthetic pigments.