Impact of changing weather on the crops yield stability in different cropping systems

R. Viikoja, M. Alaru*, I. Keres, R. Lillak, I. Voor and E. Loit

Estonian University of Life Sciences, Institute of Agricultural and Environmental Sciences, Chair of Crop Science and Plant Biology, Fr.R. Kreutzwaldi 1, EE51014 Tartu, Estonia
*Correspondence: maarika.alaru@emu.ee

Abstract:

Changes in weather conditions make it possible to change the schedule of agricultural works and introduce new crops and crop rotations in Northern Europe. It is important that the yield of the crops in the rotation are stable under highly variable weather conditions, which would ensure a high total yield for the rotation. One of the goals of this long-term field experiment (2008–2022) was to study the effect of weather conditions on the total yield and stability in the crop rotation; crops of the given crop rotation were grown in organic and conventional cropping systems.
Compared to the pre-experimental period 1964‒2007, the annual average air temperature of the test period 2008‒2022 was higher by 1.1 degrees, whereas the increase in the annual average temperature was primarily due to the increase in winter and June–July temperatures. In the 3^rd cropping cycle (2018–2022) the total yield of crop rotation as an average of fertilizer variants and experimental years was 21% and 24% lower than in the 1st (2008–2012) and 2nd (2013–2017) cropping cycles, respectively, which was mainly caused by the decrease in field pea yield. The effect of weather on yield stability was greatest for field pea. Fertilization with mineral fertilizers improved the stability of the total yield in the conventional cropping system. Correlation, factorial analyses of variance (ANOVA) and two-factor ANOVA were used to test the effect of cropping systems and climatic conditions on total and average DM yield of crop rotation, also each crop’s DM yield.
Despite the negative impact of the weather, most of the yield loss can be prevented or the damage can be eased by careful planning and detailed knowledge about the influence of different weather factors. Further investigation is required to determine the change in growing season length, sowing dates and harvesting to provide farmers more detailed tools to predict and plan their actions.

Key words:

cereals, climate change, crop rotation, field pea, potatoes, yield stability

Additive main effect and multiplicative interaction analysis of grain yield of wheat varieties in Lithuania

P. Tarakanovas¹ and V. Ruzgas²

¹Lithuanian Institute of Agriculture, Department of Grass Breeding
²Department of Cereal Breeding. Stoties Street 2, Plant Breeding Centre, Akademija, LT-58344, Kedainiai distr. Lithuania
e-mail: pavelas@lzi.lt1; ruzgas@lzi.lt2

Abstract:

Stability of 13 winter wheat (Triticum aestium L.) varieties across 4 locations and 2 years with respect to grain yield were tested in Lithuania. The analysis of variance of the 13 varieties in 8 environments shows that genotype (G), location (L), crop-year (Y) and their interaction were significant (P < 0.01) for winter wheat grain yield. Highly significant G x L effects indicated the necessity for testing wheat varieties in Lithuania at multiple locations. The article describes a previously used method and shows that AMMI (additive main effects and multiplicative interaction) model was effective for studying winter wheat genotype-environment interaction (GEI). The first bilinear AMMI model terms accounted for 76.8%. The biplot shows that the varieties Zentos, Compliment, LIA 3948, Elfas and Marshal are best suited for cultivation in a wide range of environments, while the varieties Cubus, Aristos, Marshal and LP.790.1.98 are best suited for cultivation in favourable conditions. The variety Meunier is well-suited for cultivation in poor environments. GEI patterns revealed by AMMI plots indicate that winter wheat varieties are narrowly adapted. No genotype has superior performance in all environments. The variety Elfas was the best at combining yield stability and productivity. The varieties Aristos, LP 790.1.98 and Marshal were more stable but lower yielding than Elfas.

Key words: