Sėjos laiko ir sėklos normos įtaka žieminių kviečių vystymuisi BBCH 25-30 tarpsniu

Abstract

The key objective of the research is to compare the influence of sowing time and seed rate on winter wheat (Triticum aestivum L.) during development (BBCH 25-30). It was interesting to compare leaf area index, dry matter content and crop density. The field research was performed at Vytautas Magnus University Agricultural Academy Experimental Station in years 2018–2019. Prior to the experiment, the arable layer of the soil was alkaline – pH 7.4, with the medium humus content (2.22 percent), high phosphorus content (230 mg kg-1) and medium potassium content (116 mg kg-1). Object of the research – winter wheat: ´Skagen´. The experiment was performed in four repeating cycles. The repeating cycles were randomised. The effect of seed rate on the productivity of winter wheat sown in five different sowing terms was investigated in a two-factor experiment. Factor A – Seed Rate: 2.0 million seed ha-1;3.0 million seed ha-1;4.0 million seed ha-1;5.0 million seed ha-1; Factor B – Seedtime: September 04; September 14; September 21; October 01; Winter wheat was grown according to the technology used at VDU Experimental Station. Preceding crop – summer wheat. Before seeding, winter wheat was fertilized with N16P16K16 200 kg ha-1. In the spring, during the vegetation period on the 23th of March, and second time on the 10th of April, ammonium nitrate (N61) was fertilized. And third time with ammonium nitrate (N41) on the 05th of May, plants was fertilized. Analyzing the results of the research we can state that the highest leaf area index was determined by early and optimal sowing of plants, while the delay of sowing – decreased significantly. The seed rate did not have a significant effect on the winter wheat leaf area index, except for late sowing, 2 million. ha-1 seed rate, where the leaf area index was significantly lower.[...]