Chemistry Reference
In-Depth Information
lots) and even between individual seeds from one seed lot [17, 19, 35, 36, 37, 38, 39, 40].
From the common view, the quality of root is modified by genotype, by environmental
conditions and also by seed traits, especially thanks to seed vigor and young plants traits,
especially at the poor conditions.
2. Stress during vegetation period
Water utilization by plants during vegetation period influences chemical composition of
seed, but also traits of young plants in filial generation. The availability of water and
efficiency of water utilization during germination is one of the basic factors that influence
field emergence rate and following plantlet and plant root growth. The large variability of
water use efficiency of seeds of different species and cultivars exists. This trait is under
genetic and environmental control.
For each type of stress that acts on the developing seed the different changes in subsequent
generation exist. So far obtained results confirmed that changes in the root system have
resulted not only in changes in nutrient uptake, but may be reflected in the final stages of
plant development and yield. In the case of nutrient uptake can be observed significant
cultivars differences. The largest differences in nutrient uptake between the standard
environment and stress environment (drought, high temperature, low pH) is previously in
micronutrients (especially Zn, Mn, Fe), minor differences were then at macroelements (N, P,
K, Ca, Mg). These changes may affect at more sensitive cultivars seeds properties.
In case of abiotic stress obtained results confirmed statistically significant influence of
abiotic stresses at environmental conditions on the seed traits [27, 78]. These seed traits have
a substantial effect on the tolerance to analyzed abiotic stresses in the filial generation and
also on the root system and water utilization during germination. Similar results for spring
and winter wheat were obtained [27, 78]. For example, severe stress during seed filling
caused soybean plants to exceed their capacity to buffer seed number, shifting seed weight
distributions towards a larger proportion of small seed, resulting in poor seed lot
germination and vigor [39].
Stress during vegetation period for most crops changes anatomic structures of caryopsis.
The most significant are changes in the layer of the pericarp, which creates a large number
of cells which are different in size and shape. Seed anatomical changes are in accordance
with the change of caryopsis morphology. Changing the aleurone layer structures can
greatly influence the properties of all the economically important seed. This phenomenon
highlights the importance of regularly exchange seed in crops production.
The influence of the environmental conditions changes energy content of the seeds. Grain
influenced by abiotic stress is usually less vigorous compared with non-stressed plants. Seed
vigor is also associated not only with weight, chemical composition, phytohormones
activity, but also with change of the embryo properties. Negative influence of drought and
high temperature conditions is reflected in the content of energy-rich substances
