scholarly journals Source–Sink Manipulation Affects Accumulation of Zinc and Other Nutrient Elements in Wheat Grains

Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1032
Author(s):  
Lan Wang ◽  
Haiyong Xia ◽  
Xiaojing Li ◽  
Yuetong Qiao ◽  
Yanhui Xue ◽  
...  

To better understand the source–sink flow and its relationships with zinc (Zn) and other nutrients in wheat (Triticum aestivum L.) plants for biofortification and improving grain nutritional quality, the effects of reducing the photoassimilate source (through the flag leaf removal and spike shading) or sink (through the removal of all spikelets from one side of the spike, i.e., 50% spikelets removal) in the field of the accumulation of Zn and other nutrients in grains of two wheat cultivars (Jimai 22 and Jimai 44) were investigated at two soil Zn application levels. The kernel number per spike (KNPS), single panicle weight (SPW), thousand kernel weight (TKW), total grain weight (TGW) sampled, concentrations and yields of various nutrient elements including Zn, iron (Fe), manganese (Mn), copper (Cu), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg), phytate phosphorus (phytate-P), phytic acid (PA) and phytohormones (ABA: abscisic acid, and the ethylene precursor ACC: 1-aminocylopropane-1-carboxylic acid), and carbon/N ratios were determined. Soil Zn application significantly increased the concentrations of grain Zn, N and K. Cultivars showing higher grain yields had lower grain protein and micronutrient nutritional quality. SPW, KNPS, TKW (with the exception of TKW in the removal of half of the spikelets), TGW, and nutrient yields in wheat grains were most severely reduced by half spikelet removal, secondly by spike shading, and slightly by flag leaf removal. Grain concentrations of Zn, N and Mg consistently showed negative correlations with SPW, KNPS and TGW, but positive correlations with TKW. There were general positive correlations among grain concentrations of Zn, Fe, Mn, Cu, N and Mg, and the bioavailability of Zn and Fe (estimated by molar ratios of PA/Zn, PA/Fe, PA × Ca/Zn, or PA × Ca/Fe). Although Zn and Fe concentrations were increased and Ca was decreased in treatments of half spikelet removal and spike shading, the treatments simultaneously increased PA and limited the increase in bioavailability of Zn and Fe. In general, different nutrient elements interact with each other and are affected to different degrees by source–sink manipulation. Elevated endogenous ABA levels and ABA/ACC ratios were associated with increased TKW and grain-filling of Zn, Mn, Ca and Mg, and inhibited K in wheat grains. However, the effects of ACC were diametrically opposite. These results provide a basis for wheat grain biofortification to alleviate human malnutrition.

Author(s):  
Lan Wang ◽  
Haiyong Xia ◽  
Xiaojing Li ◽  
Yuetong Qiao ◽  
Yanhui Xue ◽  
...  

In order to better understand the source-sink flow and relationships of Zinc (Zn) and other nutrients in wheat (Triticum aestivum L.) plants for biofortification and improving grain nutritional quality, effects of reducing photoassimilate source (through the flag leaf removal and spike shading) or sink (through 50% spikelets removal) in the field on accumulation of Zn and other nutrients in wheat grains of two cultivars (Jimai 22 and Jimai 44) were investigated under two soil Zn application levels. The single panicle weight (SPW), kernel number per spike (KNPS), thousand kernel weight (TKW), total grain weight (TGW), concentrations and yields of various nutrient elements (Zn, Fe, Mn, Cu, N, P, K, Ca and Mg), phytate phosphorus (phytate-P), phytic acid (PA) and phytohormones (ABA: abscisic acid, and the ethylene precursor ACC: 1-aminocylopropane-1-carboxylic acid), and C/N ratios were determined. Soil Zn application significantly increased concentrations of grain Zn, N and K. Cultivars showing higher grain yields had lower grain protein and micronutrient nutritional quality. SPW, KNPS, TKW (with an exception of TKW in half spikelets removal), TGW, and nutrient yields in wheat grains were most severely reduced by half spiklets removal, secondly by spike shading, and slightly by flag leaf removal. Grain concentrations of Zn, N and Mg consistently showed negative correlations with SPW, KNPS and TGW, but positively with TKW. There were general positive correlations among grain concentrations of Zn, Fe, Mn, Cu, N and Mg, and bioavailability of Zn and Fe (estimated by molar ratios of PA/Zn, PA × Ca/Zn, PA/Fe, or PA × Ca/Fe). Although concentrations of Zn and Fe were increased and Ca was decreased in treatments of half spikelets removal and spike shading, the simultaneously increased PA limited the increase in bioavailability of Zn and Fe. In general, different nutrient elements interact with each other and are affected to different degrees by source-sink manipulations. Elevated endogenous ABA levels and ABA/ACC ratios were associated with increased TKW and grain-filling of Zn, Mn, Ca and Mg, and inhibited K in wheat grains. However, effects of ACC were diametrically opposite. These results provide basis for wheat grain biofortification to alleviate human malnutrition.


2006 ◽  
Vol 18 (2) ◽  
pp. 341-350 ◽  
Author(s):  
José Beltrano ◽  
Marta Guillermina Ronco ◽  
María Cecilia Arango

Water deficits cause large yield losses in wheat. Although anthesis is generally considered the most vulnerable period, water deficit during grain filling can also cause yield losses. The objective of this study was to investigate the effect of water stress and rewatering, at three different grain developmental stages, on physiological and grain filling parameters and on yield components. Wheat plants were subjected to water deficit and rewatering at the watery ripe, milk and soft dough stages. In the flag leaf, water stress decreased the relative water content, the chlorophyll and protein content and increased the leakage of solutes, at all three studied grain filling stages. Water stress at the watery ripe and milk stages reduced the final grain dry mass by 47 % and 20 %, respectively. This reduction was due to a decrease in the grain filling period and to a significant reduction in the maximum rate of grain-fill. Water stress imposed at the watery ripe stage reduced not only the linear growth phase but also its slope; grain number per spike and the 1000-kernel weight were also significantly reduced. SDS-PAGE patterns of grain proteins at the watery ripe stage did not differ between the controls, stressed or rewatered treatments. Protein patterns at the milk stage changed substantially with water stress, mainly for the high molecular weight glutenin subunits and gliadins. Three new bands were observed with apparent molecular weights of 108.5 kDa, 84.8 kDa and 63 kDa. Rewatering reverted water stress effects when it was imposed at the milk stage. Water deficit at the soft dough stage did not have any effect on protein grain patterns.


Biology ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 42
Author(s):  
Cong Zhang ◽  
Bangyou Zheng ◽  
Yong He

Improving plant net photosynthetic rates and accelerating water-soluble carbohydrate accumulation play an important role in increasing the carbon sources for yield formation of wheat (Triticum aestivum L.). Understanding and quantify the contribution of these traits to grain yield can provide a pathway towards increasing the yield potential of wheat. The objective of this study was to identify kernel weight gap for improving grain yield in 15 winter wheat genotypes grown in Shandong Province, China. A cluster analysis was conducted to classify the 15 wheat genotypes into high yielding (HY) and low yielding (LY) groups based on their performance in grain yield, harvest index, photosynthetic rate, kernels per square meter, and spikes per square meter from two years of field testing. While the grain yield was significantly higher in the HY group, its thousand kernel weight (TKW) was 8.8% lower than that of the LY group (p < 0.05). A structural equation model revealed that 83% of the total variation in grain yield for the HY group could be mainly explained by TKW, the flag leaf photosynthesis rate at the grain filling stage (Pn75), and flag leaf water-soluble carbohydrate content (WSC) at grain filling stage. Their effect values on yield were 0.579, 0.759, and 0.444, respectively. Our results suggest that increase of flag leaf photosynthesis and WSC could improve the TKW, and thus benefit for developing high yielding wheat cultivars.


2017 ◽  
Vol 9 (6) ◽  
pp. 142
Author(s):  
A. Elakhdar ◽  
T. Kumamaru ◽  
M. Abd El-Aty ◽  
Kh. Amer ◽  
I. Eldegwy ◽  
...  

To understand the genetic patterns of the physio-morphological traits for barley grain yield, six-generations (P1, P2, F1, F2, BC1, and BC2) were used to determine the type of gene action in the four barley crosses. Grain yield showed a strong positive association (r = 0.83 and 1) with Grain Filling Rate in Giza121/RIL1 and Giza126/RIL2 crosses, respectively. The relationship between yield and earliness was not consistent with crosses and positive (r) values were quite low. It should be possible to select early-maturing and high-yielding segregates with high 100- kernel weight. The results indicated that the dominance effect [dd] was more important and greater than the additive effect [aa] and [ad] for most traits. Positive heterosis over the mid- and better- parent was quite similar for the most traits, except for heading and maturity dates, that showed negative heterotic effects. The inbreeding depression was high significant and positive for Grain Filling Rate, chlorophyll contents, Flag Leaf area and 100- kernel weight. On the other hand, it was a negatively significant for the earliness trait (HD, MD, and GFP). The lack of uniformity for estimates of inbreeding depression can be explained by environmental variation and to its influence on the type of gene action. Narrow-sense heritability ranged from 13.3% for Grain Filling Period in Giza12/RIL1 to 66.6% for heading dates in Giza121/RIL2 crosses. Genetic advance estimates were low due to lack of additive variance. The crosses Giza121/RIL1 and Giza126/RIL2 would be of interest in a breeding program, for improving characteristics of earliness, yield, and its components.


2002 ◽  
Vol 53 (12) ◽  
pp. 1285 ◽  
Author(s):  
Rosella Motzo ◽  
Francesco Giunta

The importance of awns in durum wheat (Triticum turgidum L. var. durum) has to be evaluated whenever an increase in grain yield is expected due to a greater photosynthetic capacity of the awned ear. Awned and awnless isolines of durum wheat were compared in a 3-year field trial in Sardinia (Italy). Ear and flag-leaf size, radiation interception, canopy temperature, yield, and yield components were measured.Awns increased the ear surface area from 36 to 59%, depending on their length, which ranged from 5.5 to 13.8 cm. This resulted in an average 4% more radiation intercepted by the awned ears. Canopy temperature was 0.9�C lower, on average, in the awned isolines, and was negatively correlated with kernel weight (r = –0.85**, n = 10), although consistent and marked effects of awns on canopy temperature were only observed in the long-awned lines. Awns positively affected grain yield, with an average increase of 10 and 16%, respectively, in the 2 years in which they affected kernel weight. The irrelevant effect of awns on yield in the year characterised by a severe drought was a consequence of their early desiccation.The effects of awns on grain yield and kernel weight strongly depend on the genetic background, on awn length and functionality, and on the environmental conditions during grain filling.


2004 ◽  
Vol 31 (2) ◽  
pp. 131 ◽  
Author(s):  
Pravat K. Mohapatra ◽  
Yasuyuki Masamoto ◽  
Satoshi Morita ◽  
Junichi Takanashi ◽  
Tsuneo Kato ◽  
...  

A super-high-yielding rice (Oryza sativa L.) cultivar, Takanari, and a traditional japonica rice cultivar, Nakateshinsenbon, were grown under field conditions to compare partitioning of 13C-labelled photosynthate to different plant organs during the period of reproductive development. The flag leaf and the two leaves immediately below it on the main culm were exposed individually to 13CO2 and the movement of the heavy carbon isotope to grains, hull, panicle branches and vegetative parts of plant was assessed. Also, the effect of a reduction of sink size on the partitioning of 13C to different organs was studied by removing some of the primary branches of the panicle. 13C taken up by the three leaves in the post-heading period, moved mostly to the grains and hull of the panicle. At this stage, the uppermost three leaves and the panicle consisted of a single source–sink unit. Partitioning of 13C to the rest of the vegetative structures of the plant was minimal. In the case of Nakateshinsenbon, the flag leaf supplied most of the carbon assimilates for the grains and contributions from the other two leaves were much smaller. However, in Takanari, the contribution of 13C to grains from the second leaf was equivalent to that of the flag leaf. In Takanari, removal of more than one third of the primary branches of the panicle significantly reduced partitioning from the third leaf of the culm, but partitioning from the flag leaf was not significantly changed. In contrast, branch removal treatment significantly depressed transport of carbon assimilates from the flag leaf in Nakateshinsenbon. The obligatory nature of the source–sink relationship in rice is discussed. It is concluded that in lower-yielding traditional rice, photosynthesis in the flag leaf supplies carbon assimilates to the developing grains. But in the super-yielding rice Takanari, the main source area is extended to include the two leaves below the flag leaf so as to sustain an extra large panicle. Even greater grain-filling is possible in super-yielding rice, if the source area is increased further.


2017 ◽  
Vol 5 (2) ◽  
pp. 194-202
Author(s):  
Ramji Prasad Bhattarai ◽  
Bishnu Raj Ojha ◽  
Dhruba Bahadur Thapa ◽  
Raju Kharel ◽  
Ankit Ojha ◽  
...  

Thirty International Maize and Wheat Improvement Centre (CIMMYT) elite lines and Nepalese commercial wheat varieties were grown at Agriculture and Forestry University, Chitwan in Alpha-lattice design to identify high yielding genotypes, yield attributing parameters and correlations between them. Observations were taken for different morpho-physiological and yield attributing traits i.e., days to booting, heading, anthesis, maturity, flag leaf senescence, flag leaf duration, grain filling duration, plant height, spike length, number of grains per spike, thousand kernel weight, hectoliter weight, grain yield and biomass yield. Significant genotypic differences were observed for all the traits studied indicating considerable amount of variation among genotypes for each character. The mean grain yield was 2148 kg/ha and it ranged from 1000 to 3425 kg/ha. BLOUK#1/4/WHEAR/KUKUNA/3/C80.1/3*BATAVIA//2*WBLL1/5/MUNAL #1 (35th ESWYT138) was the highest grain yielding genotype among all followed by CHIBIA//PRLII/CM65531/3/FISCAL/4/DANPHE#1/5/CHIBIA//PRLII/CM65531/3/SKAUZ/BAV92 (ESWYT 141), Gautam, Vijay and CHYAK1*2/3/HUW234+LR34/PRINIA//PFAU/WEAVER (ESWYT129). Grain yield had significant strong positive correlation with grain filling duration (0.685**), plant height (0.606**), thousand kernel weight (0.675**), biomass yield (0.892**) and hectoliter weight (0.586**). Four clusters were formed by cluster analysis and genotypes were grouped in a particular cluster on the basis of similarity of morpho-physiological traits. So, these genotypes may be exploited for their direct release or as parents in hybridization programmes to develop high yielding wheat varieties.Int. J. Appl. Sci. Biotechnol. Vol 5(2): 194-202


1990 ◽  
Vol 114 (1) ◽  
pp. 93-99 ◽  
Author(s):  
P. K. Aggarwal ◽  
R. A. Fischer ◽  
S. P. Liboon

SUMMARYSource–sink balance was studied by imposing different canopy defoliation treatments on wheat crops grown in Los Banos (Philippines) in 1985/86 and 1986/87, Sonora (Mexico) in 1972/73 and 1974/75 and New Delhi (India) in 1987/88. The crops were grown in replicated trials with optimum cultural management. Six defoliation treatments were imposed at anthesis on all shoots in the canopy in an area ranging between 1·65 and 3·0 m2. Defoliation reduced dry weight in proportion to the reduction in percentage light interception. The number of grains per unit land area was reduced slightly, and in most cases not significantly, except when all leaves were removed. Despite reduction of leaf lamina area index to as low as 0·5, the decrease in grain yield was small. In particular, flag leaf removal led to a remarkably small reduction in grain yield. Grain nitrogen content in defoliated crops decreased much less than expected from the amount of N removed by defoliation. The slope of the relation between reduction in grain yield with defoliation and reduction in post-anthesis dry matter accumulation was 0·56, indicating moderate source limitation for grain filling. The crops at the hottest site, in the Philippines, were less limited by source than the other crops. It is suggested that selection for smaller flag leaves may be worthwhile for high-input wheat crops.


2021 ◽  
Vol 22 (4) ◽  
pp. 2053
Author(s):  
Judit Bányai ◽  
Marco Maccaferri ◽  
László Láng ◽  
Marianna Mayer ◽  
Viola Tóth ◽  
...  

A detailed study was made of changes in the plant development, morphology, physiology and yield biology of near-isogenic lines of spring durum wheat sown in the field with different plant densities in two consecutive years (2013–2014). An analysis was made of the drought tolerance of isogenic lines selected for yield QTLs (QYld.idw-2B and QYld.idw-3B), and the presence of QTL effects was examined in spring sowings. Comparisons were made of the traits of the isogenic pairs QYld.idw-3B++ and QYld.idw-3B−− both within and between the pairs. Changes in the polyamine content, antioxidant enzyme activity, chlorophyll content of the flag leaf and the normalized difference vegetation index (NDVI) of the plot were monitored in response to drought stress, and the relationship between these components and the yield was analyzed. In the case of moderate stress, differences between the NIL++ and NIL−− pairs appeared in the early dough stage, indicating that the QYld.idw-3B++ QTL region was able to maintain photosynthetic activity for a longer period, resulting in greater grain number and grain weight at the end of the growing period. The chlorophyll content of the flag leaf in phenophases Z77 and Z83 was significantly correlated with the grain number and grain weight of the main spike. The grain yield was greatly influenced by the treatment, while the genotype had a significant effect on the thousand-kernel weight and on the grain number and grain weight of the main spike. When the lines were compared in the non-irrigated treatment, significantly more grains and significantly higher grain weight were observed in the main spike in NIL++ lines, confirming the theory that the higher yields of the QYld.idw-3B++ lines when sown in spring and exposed to drought stress could be attributed to the positive effect of the “Kofa” QTL on chromosome 3B.


2010 ◽  
Vol 56 (No. 2) ◽  
pp. 51-59 ◽  
Author(s):  
J. Qin ◽  
X. Wang ◽  
F. Hu ◽  
H. Li

A field experiment was performed to investigate the growth performance and the growth stage-dependent changes in activities of antioxidative enzymes and concentration of malondialdehyde (MDA) in leaves of rice subjected to treatment with (NF-M) or without straw mulching (NF-WM) under non-flooded conditions compared with continuously flooded treatment (CF). Compared with the NF-WM treatment, mulch application significantly increased the flag leaf area per plant before heading, tillers number and plant height at the early period of tillering stage. There was no significant difference between the yield of the NF-WM and CF treatment. However, the yield of NF-WM treatment was significantly lower than CF and NF-M treatments. Significantly higher activities of peroxidase (POD) and catalase (CAT) but lower concentration of superoxide dismutase (SOD) and malondialdehyde (MDA) were observed in straw mulching treatment than in treatment without mulching at elongation, heading and grain filling stages. The change tendency of antioxidant enzyme activity and MDA level was in line both with soil moisture status and rice yields of different treatments.


Sign in / Sign up

Export Citation Format

Share Document