In our long-term experiment the analyses of stability were conducted in one shorter (years 2001–2003) and one longer (years 1994–2003) periods by using different numbers (2–6) of varieties in each one of the periods. The results of our research proved that the method, applied can be efficiently used to analyse the environmental responses, the behaviour under varying environmental conditions of different varieties. Varieties can adapt themselves differently to favourable and unfavourable environmental conditions. In general, varieties (e.g. older varieties, like Mv 15, Mv 20, and new varieties, like Lupus, Mv Emese) that give relatively good yields under unfavourable conditions (2–3 t ha
environmental average) will utilise improving environmental conditions (7–8 t ha
environmental average) to a lesser extent and vice versa. Varieties Mv 21, GK Öthalom and Mv Palotás (a currently cultivated variety) made good use of intensive growing conditions. The data in this paper may assist in choosing varieties best suited to the production and cultivation conditions of the production site.By applying stability analyses we proved that the stability of the control treatment was the most favourable over the investigation period, which good yield stability, however, manifested at very low yield levels. Our findings showed that under more intensive environmental conditions (7–9 t ha
yield level) appropriate and optimum fertilizer application was very effective and in comparison to the control treatment the yield differences between optimal fertilizer treatments were up to as much as 1–6 t ha
. Under favourable environmental conditions the highest yields were obtained when a fertilizer ratio of N
+PK was applied. Under unfavourable conditions (these may be either or both ecological and cultivation conditions), however, only retrained, moderate fertilizer doses are recommended. Under extremely unfavourable conditions (very dry cropping year) the linear regression curves for fertilizer treatments were below those of the control treatments, which referred to yield depressions due to water deficiency.
Berzsenyi, Z., Győrffy, B. 1995. Különböző növénytermesztési tényezők hatása a kukorica Termésére és termésstabilitására (Effect of various crop production factors on the yield and yieldstability of maize
Authors:A. Kokhmetova, G. Sariyeva, and S. Kenjebayeva
There is little information on interaction between productivity, stability and drought resistance of crop. This problem is very important in Kazakhstan, where the most of the agricultural area is located in arid and semiarid regions. In this context the genotype × environment interaction (GEI) is of major importance to the plant breeders in developing improved drought resistant cultivars. In this study GEI and stability parameters of recombinant inbred lines (RILs) has been determined by field testing at three contrasting environments. The comparison of the performance and stability of the lines L3, L10, L5, L1 indicated that this breeding material tended to display better performance for main of productivity traits and stability for plant grain yield as compared with other RILs and parental forms. There was positive association between high leaf Relative Water Content (RWC), low leaf Relative Water Loss (RWL) and yield stability. Both physiological parameters (RWC and RWL) are good indicators of drought adaptation by wheat genotypes. A comparison of glume pubescent and unpubescent lines has shown close negative correlation for spike RWL and spike RWC of all pubescent RILs (R2= -0.845). So the glume pubescence can be used as a morphological marker and indirect criterion for selection of drought resistant genotypes. As a result several promising lines combining high yield stability and drought resistance has been selected and used in breeding program.
Authors:Z. Berzsenyi, T. Árendás, P. Bónis, G. Micskei, and E. Sugár
istállótrágya és a műtrágya hatása a kukorica ( Zea mays L.) termésére és termésstabilitására monokultúra tartamkísérletben. [Effect of stable manure and mineral fertiliser on the yield and yieldstability of maize ( Zea mays L.) in a long-term monoculture
The effect of sowing date, N fertiliser rate, plant density and genotype
on the yield stability of maize was analysed using 15-year data from a
5×4×5-factorial sowing date experiment, 35-year data from a two-factorial N
fertilisation experiment and 25-year data from a two-factorial plant density
experiment. Stability analysis on the experimental treatments was carried out
using the variance and regression methods. Among the variance parameters, the
ecovalence (W), the stability variance (σ²) and the yield stability
(YS) were calculated. Based on the data of the sowing date experiment the
optimum sowing date (Apr. 24) or sowing ten days later (May 5) were found to be
the most stable due to the low, non-significant values of the variance
parameters and the values close to unity for the regression coefficients (b).
Although early sowing (Apr. 14) led to a significantly higher yield than late
sowing, the yield stability was poorer for early sowing. In the long-term N
fertilisation experiment the variance parameters indicated the least yield
fluctuation at N rates of 80 and 160 kg ha-1, though the yield
stability (YS) parameter for the 240 kg ha-1 N rate was also above-average.
Regression analysis showed that the yield level and yield stability were the
same in all environments for the 160 and 240 kg ha-1 N rates. The
stability of the 80 kg ha-1 N rate was similar, but the yield level
was approx. 1.3 t ha-1 lower. The yield stability of the plant
density response of the maize hybrids was different in each maturity group (FAO
number). The stable plant density range was broadest (50-90 thousand plants ha-1)
in the FAO 200-299 group. As the vegetation period lengthened the stable plant
density range narrowed and shifted towards lower plant densities (for the FAO
400-499 and FAO 500-599 maturity groups: 50-70 thousand plants ha-1).
The variance and regression parameters of stability analysis both contributed
to the characterisation of the stability of the genotypes and cropping systems
investigated. It can be concluded from the results that high yields and yield
stability are not necessarily mutually exclusive.