6 research outputs found
THE EFFECT OF SEED SPROUTING DAMAGE ON FIELD EMERGENCE AND YIELD OF SPRING TRITICALE
In the years 1999-2001 two-factor fi eld experiments were carried out in which the effects of spring triticale seed sprouting damage on fi eld emergence, elements of the structure of yield and the yield were investigated. The research covered three cultivars: Gabo, Migo and Wanad. The statistical analysis of the results showed signifi cant effects of years and sprouting damage on fi eld emergence in all the years. Consequently, these factors affected the number of spikes per unit area, weight of 1,000 seeds and the yield in the years which were unfavourable for emergence (1999, 2000). In those years the decrease in yield, in the case of seeds with the most severe sprouting damage, ranged from 29% to 65% as compared with the control. In the favourable year 2001, in spite of a signifi cant effect of seed sprouting damage on fi eld emergence, the emergence level was so high that no decrease in the investigated elements of the
structure of yield and the yield was observed
Rumex acetosa Y chromosomes: constitutive or facultative heterochromatin?
Condensed Y chromosomes in Rumex acetosa L. root-tip nuclei were studied using 5-azaC treatment and immunohistochemical
detection of methylated histones. Although Y chromosomes were decondensed within root meristem in vivo, they
became condensed and heteropycnotic in roots cultured in vitro. 5-azacytidine (5-azaC) treatment of cultured roots caused transitional
dispersion of their Y chromosome bodies, but 7 days after removal of the drug from the culture medium, Y heterochromatin
recondensed and again became visible. The response of Rumex sex chromatin to 5-azaC was compared with that of condensed
segments of pericentromeric heterochromatin in Rhoeo spathacea (Sw.) Stearn roots. It was shown that Rhoeo chromocentres,
composed of AT-rich constitutive heterochromatin, did not undergo decondensation after 5-azaC treatment. The Y-bodies
observed within male nuclei of R. acetosa were globally enriched with H3 histone, demethylated at lysine 4 and methylated
at lysine 9. This is the first report of histone tail-modification in condensed sex chromatin in plants. Our results suggest that
the interphase condensation of Y chromosomes in Rumex is facultative rather than constitutive. Furthermore, the observed response
of Y-bodies to 5-azaC may result indirectly from demethylation and the subsequent altered expression of unknown genes controlling
tissue-specific Y-inactivation as opposed to the global demethylation of Y-chromosome DNA
Expression of the aldehyde oxidase 3, ent-copalyl diphosphate synthase, and VIVIPAROUS 1 genes in wheat cultivars differing in their susceptibility to pre-harvest sprouting
The quality of wheat grains is often negatively affected by pre-harvest sprouting (PHS), a complex trait with a poorly understood genetic background. In this study two wheat cultivars differing in their susceptibility to PHS were used to investigate expression of three genes: AAO3, CPS3 and VP1. AAO3 is coding for aldehyde oxidase 3, an enzyme involved in the synthesis of abscisic acid. CPS3 codes for ent-copalyl diphosphate synthase which belongs to the pathway of gibberellic acid synthesis. The product of VP1 (VIVIPAROUS 1) is a transcription factor which controls expression of the former two genes. The study was carried out using both developing and sprouting-induced grains. In Piko, a wheat cultivar susceptible to PHS, accumulation of the AAO3 transcript was significantly decreased, during the last stages of grain development, in comparison to S艂awa, a cultivar tolerant to PHS. In case of the CPS3 and VP1 transcripts, the differences between cultivars were especially evident from 17th to 31st day after pollination. In turn, after induction of sprouting within spikes, accumulation of the AAO3 and VP1 mRNA in the S艂awa grains was lower in comparison to that observed in the Piko grains. Moreover, accumulation of the CPS3 transcript was significantly higher for Piko than for S艂awa, both in sprouting and non-sprouting grains. According to our knowledge this report provides the first description of the AAO3 and CPS3 expression in the context of PHS, and in the future it would be valuable to correlate this information with the data on the accumulation of ABA and GA3