Influence of the climatic stress on quantitative traits in wheat genotypes recommended for cropping in the Moldavian zone

Abstract

Investigations conducted at the Agricultural Research and Development Station of Podu-Iloaiei, during 2003-2007 (years with very different climatic conditions) had as aim to point out the influence of the climatic stress on some quantitative traits in wheat varieties: Flamura 85, Eliana, Iaşi 2, Beti, Boema, Dropia, Faur, Crina, Gabriela and Moldova 83. The studied quantitative traits were number of spikes/m2, number of grains in spike, weight of grains/spike, weight of one thousand grains and grain yield. During the five years of testing, 2003 and 2007 were the unfavourable years for wheat growing in the region of Moldavia. In 2003, the number of spikes/m2 was the most affected trait with high influence on yield diminution. It had values comprised between 14 spikes/m2 in Faur variety and 73 spikes/m2 in Beti and Gabriela varieties. In 2007, drought has highly affected the weight of grains in spike, with values comprised between 0.42 g/spike in Dropia variety and 0.94 g/spike in Gabriela. The average on trial for this trait, in 2007, represented only 50% of the average of the year 2006, which was the most favourable one for wheat growing from all the five testing years. On the average of five years, for the trait number of grains in spike, Iaşi 2 variety had higher statistically ensured values, as compared with Flamura 85 control variety. On the average of five years, the weight of one thousand years had higher values in varieties Dropia (42g), Crina (41 g), Iaşi 2 (40.6 g), Eliana (40.4 g) and Faur (40.2 g), as compared with the control Flamura 85. The production capacity has varied between high limits, determined by genotype and its interaction with the environment conditions. In 2006, the yield obtained was comprised between 54.6 q/ha in Moldova 83 variety and 36.8 q/ha in Flamura 85. In 2003, the limits of the production variation were of 10.1 q/ha in Boema and 4.2 q/ha in Moldova 83. As compared with the average on trial, the lowest production was achieved in 2003 (7.1 q/ha), followed by year 2007 (14.2 q/ha). On the average of five experiencing years, the yield increase (compared to the control) was between 31% in Eliana variety and 13% in Faur variety, excepting Dropia and Moldova 83 varieties. The obtained results showed that the diversity of climatic conditions in the growing area, with frequency of drought periods, had determined a high phenotypic variability of all the quantitative traits in the studied wheat genotypes. Yield losses were high in all the varieties, representing 86% in 2003 and 71% in 2007, as compared with the yield obtained in 2006.