An experiment was set up with 10 maize (Zea mays L.) genotypes in 2010 in order to study the effect of various durations of storage on the biological value of the seed and the correlation between seedling parameters and field grain yields.

Samples taken from seed lots of different genotypes stored for 1–11 years were examined in germination, vigour and cold tests. Apart from the usual parameters, a record was also made of the shoot fresh weight, root fresh weight and shoot length of 4-day-old seedlings. Laboratory analysis was followed by field trials, where emergence, plant development, silking, grain moisture at harvest, biotic stress sensitivity and grain yield were scored. Storage for five years or more led not only to a significant decline in seed vigour, but also to slow, protracted juvenile development, resulting in delayed silking and an increase in grain moisture at harvest. The mass and shoot length of seedlings subjected to stress decreased significantly with an increase in the storage period. The shoot mass of seedlings developing in a cold, oxygen-deficient environment was higher than the fresh root mass after any length of storage.

A close correlation was found between the vigour of stressed seedlings (complex stressing vigour test: CSVT) and the grain yield (Y’), with an r2 value of 0.805 (hybrid Mv 384 and Mv 265) and the regression equation: Y’=6.35+0.018 CSVT. An even closer correlation was obtained (r2=0.84) between the fresh weight of the seedlings (SW) and the grain yield (Y’) in the case of hybrids Mv 343, Mv 384 and Mv 394 (regression equation: Y’=11.5+0.74 SW). There was a looser correlation (r2=0.37–0.55) between the fresh root weight of the seedlings (RW) and the grain yield (Y’), with the exception of the hybrid Mv 384 (regression equation: Y’=11.61+1.18 RW). It can be concluded that the field performance of the genotypes does not always depend on the duration of storage. The initial vigour of the seed could be a more reliable indication of expected performance.

Keywords: deterioration, storage, seedling vigour, yielding ability