scholarly journals Response of floret fertility and individual grain weight of wheat to high temperature stress: sensitive stages and thresholds for temperature and duration

2014 ◽  
Vol 41 (12) ◽  
pp. 1261 ◽  
Author(s):  
P. V. Vara Prasad ◽  
Maduraimuthu Djanaguiraman

Short episodes of high temperature (HT) stress during reproductive stages of crop development cause significant yield losses in wheat (Triticum aestivum L.). Wheat plants of cultivar Chinese Spring were grown at various temperature regimes at several stages of reproductive development for different durations. The objectives of this research were to (i) identify the stage(s) most sensitive to HT stress during reproductive development, and (ii) determine threshold temperature and duration of HT stress that decrease floret fertility and individual grain weight. Two periods (first at 8–6 days before anthesis and second at 2–0 days before anthesis) during reproductive development were most sensitive to short episodes (2 or 5 days) of HT stress, causing maximum decreases in floret fertility. Short episodes (5 days) of mean daily temperatures >24°C imposed at start of heading quadratically decreased floret fertility, with the values reaching close to 0% around mean daily temperature of 35°C; and floret fertility and individual grain weight decreased linearly with increasing duration (in the range from 2 to 30 days) of HT stress when imposed at start of heading or start of grain filling respectively. HT stress caused morphological abnormalities in pollen, stigma and style. The combination of lower floret fertility (leading to decreased grain numbers) and decreased individual grain weights can cause significant decreases in grain yield. Further research to search for genetic variability for these traits and use them in breeding programs to develop tolerant genotypes that can provide yield stability under current and future climates is warranted.

2020 ◽  
Vol 63 (3) ◽  
pp. 214-225
Author(s):  
Saquib Hussain ◽  
Qamaruddin Chachar ◽  
Sadaruddin Chachar ◽  
Bahram Khan Chachar ◽  
Wajid Ali Jatoi ◽  
...  

  To observe the effect of high temperatures stresses i.e., normal (25 °C), high (30 °C) and very high (35 °C) stress, on germination and seedling growth on wheat genotypes a water culture study was conducted under controlled conditions (growth incubators). Eighteen newly developed wheat lines (DH- I, DH-3, DH-4, DH-5, DH-6, DH-7, DH-8, DH-10, DH-11, DH-12, DH-13, DH-14, DH-15, DH-16, DH-18, DH-19, DH-20 and DH-21) were tested along with two local checks i.e., Kiran-95 and LU-26s. There was a gradual reduction in germination and seedling growth at 30 °C and 35 °C. Among the tested genotypes the genotype DH-16 showed least reduction i.e. only 2.27% reduction in germination at 35 °C. On the other hand the genotype DH-6 showed maximum reduction (28.09%) at 35 °C. High temperature stresses also affected on other growth parameters i.e. shoot and root length (cm), fresh and dry matter (g) of shoot and root and the moisture contents. It is based on relative reduction over control in various growth parameters at very high temperature stress (35 °C), four genotypes viz., DH-3, DH-5, DH-8 and DH-13 appeared as tolerant, nine genotypes i.e., DH-1, DH-4, DH-7, DH-10, DH-11, DH-14, DH-18, and LU-26s appeared as medium tolerant and two as medium sensitive i.e. DH-6 and DH-16. On the other hand six genotypes viz., DH-12, DH-15, DH-19, DH-20, DH-21 and Kiran-95 showed sensitivity 35 °C over 25 °C. It is therefore concluded that the genotypes DH-3, DH-5 and DH-13 can be cultivated on heat prone areas of Pakistan especially in Sindh province.    


2020 ◽  
Vol 53 (2) ◽  
Author(s):  
Khalil Ahmed Laghari ◽  
Abdul Jabbar Pirzada ◽  
Mahboob Ali Sial ◽  
Muhammad Athar Khan ◽  
Jamal Uddin Mangi

Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 687
Author(s):  
Chan Seop Ko ◽  
Jin-Baek Kim ◽  
Min Jeong Hong ◽  
Yong Weon Seo

High-temperature stress during the grain filling stage has a deleterious effect on grain yield and end-use quality. Plants undergo various transcriptional events of protein complexity as defensive responses to various stressors. The “Keumgang” wheat cultivar was subjected to high-temperature stress for 6 and 10 days beginning 9 days after anthesis, then two-dimensional gel electrophoresis (2DE) and peptide analyses were performed. Spots showing decreased contents in stressed plants were shown to have strong similarities with a high-molecular glutenin gene, TraesCS1D02G317301 (TaHMW1D). QRT-PCR results confirmed that TaHMW1D was expressed in its full form and in the form of four different transcript variants. These events always occurred between repetitive regions at specific deletion sites (5′-CAA (Glutamine) GG/TG (Glycine) or (Valine)-3′, 5′-GGG (Glycine) CAA (Glutamine) -3′) in an exonic region. Heat stress led to a significant increase in the expression of the transcript variants. This was most evident in the distal parts of the spike. Considering the importance of high-molecular weight glutenin subunits of seed storage proteins, stressed plants might choose shorter polypeptides while retaining glutenin function, thus maintaining the expression of glutenin motifs and conserved sites.


2017 ◽  
Vol 42 (1) ◽  
pp. 53-65
Author(s):  
Mohammed Humayun Kabir ◽  
Qing Liu ◽  
Yi Su ◽  
Zhigang Huang ◽  
Langtao Xiao

A pot experiment on an early indica rice cv. ‘Shenyou9576’ was conducted in the net house of Hunan Agricultural University, Changsha, Hunan, PR China during the early growing season of 2013 to investigate the influence of varying temperatures on chalkiness rate, head rice rate, and phytohormones, namely indole-3-acetic acid (IAA), gibberellins (GA1 and GA4), zeatin (Z), zeatin riboside (ZR) and abscisic acid (ABA) both in flag leaves and grain endosperm during grain filling period. The treatments comprised three temperature regimes which are designated as the high (35/28oC- day/night), low (25/20oC- day/night) and natural condition as the control (35/25oC- day/night). The results showed that the maximum chalkiness rate was 61.11% under high temperature and the minimum (22.59%) under low temperature. The lowest head rice rate was 42.76% under high temperature followed by 49.91% in the control, while the highest (62.33%) under low temperature. The contents of GA1, GA4, Z and ZR were decreased gradually from 7 to 35 days after anthesis (DAA) irrespective of treatments. IAA content began to decrease from 14 DAA and continued up to 35 DAA and ABA was reduced from 28 to 35 DAA under low temperature in comparison to control and high temperature. ABA content was increased from 7 to 21 DAA and then declined at high temperature. The results showed that contents of GA1, GA4, Z, ZR were high at low temperature compared to high temperature and control. IAA content was also high during grain development period at low temperature except 7 DAA. Higher phytohormone contents were observed in endosperm than in flag leaves. Phytohormone content ratio (endosperm: flag leaves) was found highest in IAA and the lowest in GA1. A significant positive correlation was found between ABA and chalkiness rate during early to mid grain filling period, while significant negative correlations were noticed between chalkiness rate and other phytohormones during grain filling period. Correlation results revealed that increased level of ABA during early to mid grain filing period caused by high temperature was more responsible for development of chalkiness.Bangladesh J. Agril. Res. 42(1): 53-65, March 2017


1994 ◽  
Vol 21 (6) ◽  
pp. 791 ◽  
Author(s):  
CF Jenner

As temperature rises above 18-22�C, the observed decrease in the duration of deposition of dry matter in the kernel is not accompanied by a compensating increase in the rate of grain filling with the result that grain weight (and yield) is diminished at high temperature. Reduced starch content accounts for most of the reduction in grain dry matter at high temperature. Responses to temperature in the low temperature range, 20-30�C (the LTR), could possibly be ascribed to the temperature response characteristics of the reaction catalysed by soluble starch synthase (SSS), the enzyme synthesising starch. However, the rate of cell enlargement and the rate of accumulation of nitrogen in the grain also do not increase much as temperature rises, so other explanations are conceivable for the temperature responses in the LTR. Variation amongst cultivars of wheat in tolerance of high temperature is evident in the LTR. At temperatures above 30�C (in the high temperature range (HTR) between 30 and 40�C), even for short periods, the rate of starch deposition is slower than that observed at lower temperatures, an effect which is carried over after transfer from high to lower temperatures. This response is attributable to a reduction in the activity, possibly due to thermal denaturation, of SSS. Several forms of SSS are found in cereal endosperm, and some forms may be more tolerant of high temperature than others. Loss of enzyme activity at high temperature is swift, but is partly restored some time after transfer from hot to cool conditions. There appear to be two distinct mechanisms of response to elevated temperature, both resulting in a reduced grain weight through reduced starch deposition, but one of them is important only in the range of temperature above 30�C.


Euphytica ◽  
2005 ◽  
Vol 141 (1-2) ◽  
pp. 41-48 ◽  
Author(s):  
Valeria S. Passarella ◽  
Roxana Savin ◽  
Gustavo A. Slafer

Crop Science ◽  
2016 ◽  
Vol 56 (4) ◽  
pp. 1561-1572 ◽  
Author(s):  
Vijaya Singh ◽  
Chuc T. Nguyen ◽  
Zongjian Yang ◽  
Scott C. Chapman ◽  
Erik J. van Oosterom ◽  
...  

2020 ◽  
pp. 43-48
Author(s):  
M. D. Маkоvеi

Relevance. The article presents the results of using three different selection methods to obtain new forms of tomato that combine high productivity with resistance to high-temperature stress factor.Methods. Eleven hybrid combinations were used as experimental material. Selections were made starting with the offspring of the F1 generation. Three different methodological approaches were used: 1 – step-by-step alternation of sporophytic-gametophytic selections under high temperature pressure; 2 – only gametophytic selection using heat-treated pollen for pollination; 3 – traditional selections based on a high value of indicators of the studied traits. In each of the variants of the experiment, we studied: the heat resistance of offspring at different stages of ontogenesis – "sporophyte-gametophyte"; the duration of the vegetation period of plants; the fruit formation; the total yield. The offspring of the most stable and productive plants isolated from different hybrid combinations were combined in the populations in each variant of the experiment and a comparative analysis and evaluation of the effectiveness of the methods used was carried out.Results. It is shown that the combination of step-by-step sporophyte-gametophyte selections under the action of high-temperature regimes (43°C and 45°C), at early stages (F1–F3) lead to more stable, productive offspring in F5-F7 both for sporophyte and gametophyte traits, compared to using only gametophyte selections and stronger differences relative to the control variant. The gradual alternation of selections at different stages of ontogenesis also leads to the production of offspring with a shorter period of passage of the phenophases "seedling-flowering" – "floweringmaturation" and a stable manifestation of signs that determine the quality of the fruits. Using only gametophytic selections and traditional methods of selection was less effective than alternating sporophyte-gametophyte ones.Conclusions. The differentiating ability of the selection methods used and their influence on obtaining more resistance and productive genotypes was established. The advantage of the method of step-by-step alternation of sporophyte-gametophyte selections, which led to the production of new lines (118/1, 124/1, 133-11/1, 133-12/1, 134/1, 110/1 and 7/1) with high resistance at different stages of ontogenesis (sporophyte-gametophyte), shorter vegetation period and high fruit-forming capacity in three different years of research (2015-2017).


Sign in / Sign up

Export Citation Format

Share Document