Effects of Water Supply and Light Intensity on the Growth of Spring Wheat.

Abstract

The effects of water supply and light intensity on the growth of spring wheat (Triticum aestivum L.) was studied under carefully controlled conditions. The leaf water potential (LWP) was measured from 5 to 40 d after the initiation of water supply treatments (DAIT). The LWP decreased as DAIT progressed. At higher photosynthetic photon flux densities (PPFDs), the LWP decreased as the water supply decreased. The water supply rate had little impact on tiller initiation and survival under low PPFD. As the PPFD increased, however, tillering responded sharply to water supply. Differences in tiller numbers were mainly due to differences in the number of subtillers from T0, T 1 and T2 primary tillers. The water supply rate did not affect plant growth significantly under low PPFD. Increased PPFD resulted in increased plant growth, except for leaf numbers per main stem, as water supply rate increased. Thus, there was a highly significant interaction of water supply and light intensity on the growth of spring wheat.

Simultaneous effects of leaf irradiance and soil moisture on growth and root system architecture of novel wheat genotypes: implications for phenotyping

“…A similar reduction in root length of 43% was shown for castor bean plants ( Penfound, 1932 ). For wheat plants, Tamaki et al (2001) reported an inhibition of 68% in root biomass under combined low light and low water availability. The difference in reduction on wheat plants could be ascribed to the discrepancy in time points when plants were measured or harvested.…”

“…The difference in reduction on wheat plants could be ascribed to the discrepancy in time points when plants were measured or harvested. Tamaki et al (2001) harvested the plants at anthesis whereas the plants in this study were grown for only 3 weeks in rhizoboxes (because roots reached the bottom of the rhizoboxes 3 weeks after sowing and measurements were stopped). During these 3 weeks, inhibition of root extension increased from 23% to 42% and it may have increased more over plant development up to 68% at anthesis.…”

“…During these 3 weeks, inhibition of root extension increased from 23% to 42% and it may have increased more over plant development up to 68% at anthesis. However, Tamaki et al (2001) did not quantify root growth continuously, so it is not possible to be certain.…”

“…However, there are differing predictions about whether a given soil moisture availability has a stronger impact than leaf irradiance on the vegetative growth of shoots and roots. To date, there have only been a few studies that deal with the combination of drought and light treatments, and these have shown species-specific results: low light (under high soil water content) induced the dry-matter allocation to the shoot of castor bean ( Ricinus communis ; Penfound, 1932 ) and Picea seedlings ( Yang et al , 2008 ) but reduced shoot biomass of Amomum villosum ( Feng and Li, 2007 ) and wheat ( Tamaki et al , 2001 ). Likewise, diverse reactions have been found under low light in combination with low soil moisture in terms of reduced biomass partitioning to roots.…”

Acceleration of wheat breeding: enhancing efficiency and practical application of the speed breeding system

“…S1a and b). This may be because plant growth is influenced by various conditions, including light intensity, light spectrum, temperature, and CO 2 concentration [13,17,[21][22][23]. Bhatta et al [13] reported that higher plant height and GN were observed in a glasshouse than in a speed-breeding room, although this was the result of delayed DTH in a glasshouse with a natural photoperiod.…”