Author:
Corbellini M.,Canevar M.G.,Mazza L.,Ciaffi M.,Lafiandra D.,Borghi B.
Abstract
High temperatures occurring during grain filling are known to affect wheat
grain yield and quality considerably. In this paper we report the results of
experiments carried out with two cultivars of bread wheat
(Triticum aestivum L.) and two cultivars of durum wheat
(Triticum durum Desf.). The plants, cultivated in pots,
were subjected to 13 heat treatments (temperature up to 40°C) differing in
duration and timing and starting 7 days after anthesis. Heat treatments were
applied by temporary transfer of the pots to a glasshouse where the
temperature rose to 40°C as a consequence of solar radiation for periods
ranging from 5 to 30 days. The applied heat shocks substantially affected dry
matter and protein accumulation in the different parts of the plant. Early
heat shock (5 days with a total of 18 h of temperature in the range
35–40°C) caused a small reduction of kernel mass and no effect on
protein per kernel; the damage was greater in the central and in the final
stage of grain filling. Plants subjected to a progressive increase of
temperature, or to an early heat shock, acquired thermotolerance to further
heat shocks. Continuous exposure to very high temperatures from 27 days after
pollination to maturity did not negatively affect grain yield and it
facilitated the remobilisation of nitrogen from vegetative to reproductive
organs. Rheological properties were severely affected by heat shocks at all
stages of grain filling: 5 days of heat shock were sufficient to reduce mixing
tolerance by 40–60%. These variations in rheological properties
were accompanied by modification of the level of protein aggregation: soluble
polymeric proteins and low molecular weight gliadins progressively increased
according to the intensity of the stress, while insoluble polymeric proteins
decreased.
Our experiments, carried out in conditions close to the Mediterranean climate,
indicate that the occurrence of very high temperature in the range
35–40°C during grain filling substantially affects dry matter and
protein accumulation in the different parts of the plant. The formation of the
complex protein aggregates responsible for positive dough mixing properties is
significantly reduced by very high temperature. When heat shock came late in
grain filling, grain yield and protein concentration were not negatively
affected but a ‘dough weakening’ effect, which may reduce the
commercial value of the production, is to be expected.
Subject
Plant Science,Agronomy and Crop Science
Cited by
90 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献