3 M urea has been shown to cause considerable, and only partially reversible conformational changes of gluten molecules. Homogenization has proved to act mechanically, breaking down some molecular bonds. No structural changes could be observed during freeze drying gluten, as well as after brief heating of its acetic acid extracts.

The β-endoglucanase is one of the enzymes taking part in the degradation of the cell wall structural polysaccharides. The use of two Triticale varieties differing in their resistance to the preharvest sprouting allowed the comparison of that enzyme activity and changes in the internal structure of the cell wall observed in the light and electron microscope. The most interesting observations seem to be the channels and even the holes in the walls of aleurone cells found mostly in the samples showing the elevated activities of β-endoglucanase. As those samples concern the grains of a lower resistance to pre-harvest sprouting, it might be suggested that the loosening of the wall structure may be one of the probable mechanisms in facilitating the enzyme, metabolite and water translocations through the grain tissues. Those changes can accelerate the water imput into the grain, the metabolic process and thus the increased susceptibility to sprouting.

The dynamics of activity changes of beta-glucanase and alpha-amylase were investigated on two Triticale cultivars of different pre-harvest sprouting resistance. Five milling fractions earlier described were used for the investigations and the alpha-amylase activity was determined on two substrates: primary and soluble starch. There was demonstrated the 2.6 times higher affinity to the first as compared with the second when alpha-amylase with a high-isoelectric point (high-pI) (Sigma) was used being the main enzyme degrading starch during germination. The beta-endoglucanase activity was the highest in the embryos, particularly in Malno, in 24 and 48 h and the lowest, but higher than in Malno, in the internal endosperm (by 50% in 48 h and 14% in 72 h). Particularly high differences, in favour of Malno, were also observed in the aleurone fraction (40-41% from 0 to 48 h and 14% in 72 h). Those differences can point to the higher effectiveness of the cell wall degradation inside the grains of the susceptible Malno cultivar which is connected with the possibility of the easier transport of metabolites at the time of starch degradation. In the susceptible Malno cultivar the alpha-amylase synthesis with the high degree of affinity to the native starch took place earlier and in a more intensive way than in the resistant Lasko cultivar with the exception of both fractions of the endosperm to which that form was transferred from the scutellum and the aleurone layer only in 24 h in Malno and 48 h in Lasko. Such conclusions were based on the gradual increase of the ratio of the activity determined on the native starch to that determined on the soluble starch thus testifying to the increase of the share of alpha-amylase with a high affinity to the first one. The compared results of the alpha-amylase determinations on both substrates points to varied affinities to starch of different isoforms of that enzyme that should be considered while drawing conclusions as to the activity of the total alpha-amylase.

The level of non-protein N and the total, aspartyl, cysteine and serine endopeptidase activities were determined in 5 milling fractions (embryonic, seed coat, aleurone layer and two flour subfractions) of resting grains and those subjected to 24, 48 and 72h imbibition of two varieties of Triticale: susceptible and resistant to pre-harvest sprouting.The results show that in the resting grain and during the initial imbibition period the aspartyl proteinase contribution to the total endopeptidase activity was the highest but its increase rates during the first three days of germination were the smallest. At the same time significant increases of cysteine proteinase and about three times smaller of serine proteinase activities were observed in the embryonic fraction and in the aleurone layer. After 24 or 48h germination there was a significant translocation of those two enzymes towards both endosperm fractions. Those phenomena were faster in the susceptible Malno variety than in resistant Lasko. The results confirm the suggestion that aspartyl proteinase may be synthetized mainly in the developing grains and it should initiate grain storage protein degradation. Since the cysteine proteinase contribution to the total proteinase activity became dominant starting of 48h germination it should be regarded as the main enzyme catalysing the breakdown of these proteins. The comparison of the data obtained for grains of different pre-harvest sprouting resistance suggests the faster translocation of endopeptidases through the tissue in the susceptible Triticale variety, than in resistant one.

The investigations included the total endopeptidase activity changes, and those of aspartyl, cysteine and serine ones, as well as carboxypeptidase in the developing Triticale grain of the Lasko cultivar - resistant to pre-harvest sprouting and Malno, the susceptible one. Besides, the mentioned enzymes in the seed, also their distribution in three fractions of grain of those cultivars, namely the seed coat, aleurone layer and endosperm was investigated at three chosen stages of development (18, 27 and 39 dap). It has been demonstrated that the initial significant activity of total endopeptidases and their three particular types decreased during the grain development until 38 dap and then became stabilized. On the other hand the initially low carboxypeptidase activity increased slowly until 31 dap and then was stabilized. Out of the investigated fractions the highest total endopeptidase activities were observed in the seed coat and about twice smaller in the aleurone layer and they decreased during the grain development. Similar behaviour was observed for particular types of endopeptidases, the smallest significance of which was thought to he the serine enzyme and in the endosperm and aleurone layer there was the dominance of the cysteine endopeptidase. Contrary to them the highest carboxypeptidase activity occurred in the endosperm increasing during the development. The activity of that enzyme only showed a clear predominance in Malno as compared to Lasko.

Five selected winter Triticale varieties differentiated in pre-harvest sprouting resistance were analyzed as concerns the dynamics of various types of proteolytic activity, as well as non-protein N increase during grain germination in provocative conditions. The total endopeptidase and esterase (BAPA-ase) activities, as well as those of aspartic-, cysteine-, serine- and metall peptidases were determined.The total endopeptidase activity of resting grains and of those subjected to imbibition for 24 h was low and only slightly differentiated between varieties. The significant increases and higher varietal differences, contrary to the suggested resistance, were observed between 24 and 48 h of imbibition. The BAPA-ase activity demonstrated high differences in resting grains, which can suggest its synthesis related to pre-harvest sprouting susceptibility in the course of grain development, whereas during germination its activity changed to lesser extent and not regularly. The serine- and metall-peptidase activities were low and seem to be of the lesser significance in the mobilization of storage protein N. The aspartic peptidase was significantly synthesized during grain development, but also to some extent during germination. On the other side the cysteine peptidase was formed mainly during germination whith the rate 6 times higher than that of aspartic one. Aspartic peptidase was likely to be the most important in protein degradation during the first 48 h, but at 72 h the cysteine peptidase seems to be dominant in total activity, particularly in case of Malno variety. The rate of non-protein N increase were about 1.7 times larger for Malno, than for Lasko, but the differences between other three varieties was rather small. The results show, that besides the tactors investigated hitherto, other metabolic differences between grains of various resistance to pre-harvest sprouting, may be investigated as well.

5 samples of winter Triticale grains differing in the pre-harvest spouting resistance, used in three preceeding papers of this series were investigated as concerns the change dynamics of phytase, acid phosphatase and 1-3, 1-4-beta-endoglucanase activities, as well as the level of phytate and inogranic P during the initial three days of imbibition. Some of the mentioned enzymes were suggested to participate in the building up the cell membrane, thus to influence the imbibition rate.Only in few cases the significant varietal differences were observed, but mainly they were not well related to the pre-harvest sprouting resistance. The phytate level showed neither varietal nor germination course differences. The phytase and acid phosphatase activities increased during the initial 8 h 2.5-3-fold and after 24 h the further rise, not higher than for 30% was observed, being the highest in the susceptible variety Malno (40-60% higher, than in resistant Lasko). The beta-glucanase activity and the P(i) level remained stable during the initial 24 h imbibition, increasing since then to reach 3-3.5-fold values in the former and 2-3-fold ones in the latter case. None of the investigated factors was demonstrated to be directly related to pre-harvest sprouting resistance, although they showed some, but mostly irregular varietal differences.

Factors differentiating the pre-harvest sprouting resistance were investigated and the embryo development conditions during the kernel growth were analyzed. The dynamics of dry and fresh matter, sucrose and monosaccharide accumulation were determined in developing Triticale grains of five varieties of different pre-harvest sprouting resistance.The significant initial increases of sucrose level, as calculated per one karnel, as well as higher osomolarity in the tissue were observed in varieties resistant to pre-harvest sprouting. Sucrose level and higher osmolarity might be connected with their inhibitory effect on the embryo. The water content increases between the first and second week of experiment were high in case of Lasko (3-fold), but lower in other varieties (2-2.5-fold). Further water increases were slower and more regular in Lasko and Presto, than in other varieties (about 11% weekly until the fifth one). The less regular water changes could present the negative influence on the structure of cell membranes, when occurred during the suggested period of intolerance. Particularly large water loss in the very last developmental stage observed in Malno and Moniko could be harmful to this structure.Sprouting mte of unthreshed kernels (in spikes) in provocative conditions were carried out. This way of variety pre-harvest sprouting resistance estimation, as closer to the natural conditions, seems to be more proper for such comparisons.

Changes of some hydrolytic enzyme activities were investigated in the developing grains of 5 winter Triticale cultivars of different pre-harvest sprouting resistance. Samples were harvested weekly beginning on ninth day after pollination (dap) until full maturity (7 times) and the following enzymes were analyzed: alpha-amylase and total amylolytic activity, beta-endoglucanase, acid phosphatase and total proteinase. The endogenous alpha-amylase inhibitor level was analysed as well. The intervarietal differences which could be connected with the pre-harvest sprouting resistance were observed only in case of alpha-amylase, beta-endoglucanase and acid phosphatase. The activity of alpha-amylase showed such dependence in the earlier period of development (up to 30 dap) being lower in the resistant varieties and higher in the susceptible ones. beta-endoglucanase showed similar relation but only in the final maturation period. Also the acid phosphatase activity in some harvests was higher in the susceptible varieties than in the resistant ones. However, there are obtained too few data to formulate any final conclusions.

Grain germinated under provocation conditions of five selected varieties of winter Triticale differentiated by the resistance to pre-harvest sprouting were used to determine the dynamics of reducing sugar increase, as well as total amylolytic and alpha-amylase activities.The very slow increase of reducing sugar level was observed at the beginning of grain germination, being accelerated significantly after 24 h. At 48 h it reached about 6-fold increase in case of varieties resistant to pre-harvest sprouting and over 9-fold :increase in those susceptible to this feature. It is suggested, that this behaviour, together with the respiration rate might be regarded as the suitable index of pre-harvest sprouting. There were not shown, however, regular differences of the total amylolytic and alpha-amylase activities, which were found to be present in dormant grains rather high, as compared to those of other cereals. During first 8 hs of germination the increase of beta-amylase and, maybe of some auxiliary activities was suggested to take place, but after 24 h - also that of alpha-amylase. The amylase activities seem to occure in excess in Triticale and not to be bound with pre-harvest sprouting. Therefore the falling number seems to be trot fully suitable way for Triticale evaluation.

Some winter Triticale varieties selected by breeders as concerns their pre-harvest sprouting resistance, were investigated in order to confirm the relationship of this practical property with some physiological ones. The rate of germination initiation (per cents of sprouted grains and length of growing roots), the water imbibition rate and respiration intensity were determined. Grains were germinated at provocation conditions (100% humidity, 22 degrees C) during the period 0 - 72 h.There was shown, that after 36 h grains of all varieties investigated were already sprouted, but the rates of root growth were differentiated and remained in the opposite relations to the sprouting resistance suggested by breeders. Similar relationships were observed also in case of water uptake and respiration intensities. On the base of processes indicating grain metabolism initiation the significant resistance of Lasko and Presto varieties, but the susceptibility of Malno and Moreno ones, when maintained in provocation conditions, were demonstrated.It can be suggested therefore, that the relationships between germination indexes determined and the pre-harvest sprouting might exist.

In the resting grains of selected winter Triticale lines and in the developing ones of the variety Lasko, growing in two following seasons the activities of alpha-amylase, as well as free and bound beta-amylase were investigated. The contents of reducing sugars, starch and protein were determined as well. The higher activity of both amylases was observed in samples characterized by lower hectolitre weights and kernel filling as compared to the lower activities in samples of higher hectolitre weight and kernel filling. Parallelly, in the former samples the lower starch, but the higher reducing sugar contents in comparison with the latter ones were observed. Also higher protein percentage for the former and the lower one for the latter samples were characteristic. In developing grains of winter Triticale cv Lasko two periods of an intensive increase in the activity of both enzymes were distinguished. The first one appeared when the grain dry matter amounted to 28-35% (i.e. between 28th and 40th day after flowering, but the second one started at the beginning of the full maturity phase (i.e. when the grain dry matter percent amounted-to about 70),

The fractional composition of proteins extracted from wheat flour samples of different baking quality was determined in order to find some relationships between the fraction contents, total extractability, and the E280 /total N ratios of separate extracts and the baking quality of flour. There has been found an influence of the quality of fluor on the decrease of total extraction of protein and that of E280 /total N ratio of NaOH extracts containing high mol. weight glutenin. As those flour properties should be of importance in technology and nutrition, the possibility of their direct hereditability in F1 generation, using crossings between male sterile mother lines and fertility restoring father ones, was investigated. It has been shown, that the fractional composition of wheat proteins can be directly hereditable, the influence of mother line being much stronger than that of father line. Also, the influence of mother line on the hereditability of E280 /total N ratio was found to be probable, although the results were found to be less regular.