The productivity and yield stability of winter rye variety 'Vambo' in long term NPK fertilization trial on calcaric cambisol

• Main Author: Valli Loide
• Format: Article
• Language: English
• Published: Estonian Academic Agricultural Society 2015-12-01
• Series: Agraarteadus
• Subjects: rye productivity; effectivness of fertilizers; weather conditions; stability of yields
• Online Access: http://agrt.emu.ee/pdf/2015_2_loide.pdf

The productivity and yield stability of winter rye has been investigated in long term fertilization trial on Calcaric Cambisol. The diploid rye variety 'Vambo' was one of the cultures used in the trial in years 1975 till 2014. The trial was established as six-year crop rotation (potato-late maturing spring barley-undersown early maturing spring barley-first year grass clover mixture-second year grass clover mixture-rye). In the trial the traditional agrotechnical measures were applied: ploughing, using of herbicides and plant protection measures. The trial consisted of 21 combined variants of NPK mineral fertilisers and farmyard manure variants of 30 and 60 t ha-1. NPK-fertilizers (kg ha-1 as element) levels are as follow: 000 = N0P0K0; 111 = N45P13K30; 222 = N90P26K60; 333 = N135P39K90; 433 = N180P39K90. Weather conditions of trial are given in figures 1–2. Averagely of 19 years the rye yield from unfertilized plot (Figure 3) was 1.9 t ha-1, by using of mineral fertilizers in level 3 (N135P39K90) the yield was 4.1 t ha-1. The effect of farmyard manure combined with mineral fertilizers was modest (Table 1) because the organic fertilizer was applied to the first culture in crop rotation (potato) and the last culture rye didn’t get any benefit from that. The weather conditions had bigger impact on yield than fertilization. Different fertilizing levels (Figure 4) have had positive effect on rye productivity, but the variability was remarkable. The increasing of productivity is most probably connected to the good weather conditions in September. But in the same time the variability in productivity was increased due to unfavourable conditions in September like the increasing of temperatures and decreasing of precipitation (dry periods in the beginning of rye growth). The best stability of yields was recorded in fertilization level 333 (N135P39K90) where the average yield levels of 3–5 t ha-1 was 84%. In the same time the fertilization levels 222 and 221 gave the same productivity 74 and 53% accordingly. Compared to the smaller rates of fertilization the plots with higher fertilization rates (NPK 222 and higher) resulted in smaller variability in yields (Figure 6).