TEMPERATURE AND PHOTOPERIOD RESPONSES OF EARLY-MATURING SORGHUM HYBRIDS

1977 ◽  
Vol 57 (3) ◽  
pp. 757-761 ◽  
Author(s):  
YILMA KEBEDE ◽  
D. J. HUME
Keyword(s):  
Grain Filling ◽  
Grain Weight ◽  
Temperature Regimes ◽  
Early Maturing ◽  
Number Of Leaves ◽  
Grain Filling Period ◽  
Shoot Weight ◽  
Type Of Behavior ◽  
Sorghum Bicolor L ◽  
Weight Number

This study was designed to assess the response of three early-maturing sorghum (Sorghum bicolor L. Moench) hybrids, Pride P130, X4043, and X3160, to different day and night temperature regimes and photoperiods under controlled environment conditions. Day/night temperatures were 25/20, 30/20, 35/20, 30/15, 30/25 C with a 12-h photoperiod and 30/20 with a 16-h photoperiod. Data on days to bloom, plant height, number of leaves, number of panicles per plant, duration of grain filling, grain weight, shoot weight and harvest index were obtained. Largest grain weights were obtained at 25/20 C. Grain weight, number of panicles, and grain-filling period were reduced markedly by 5 C increments in day temperature. X4043 and X3160 bloomed soonest at 30/20 C. P130 bloomed and matured in fewer days than the other hybrids at all temperatures. The response of the hybrids to a 16-h photoperiod indicated that they all had a long-day type of behavior at the temperature regime tested.

scholarly journals Dynamics of phytohormones and their relationship with chalkiness of early indica rice under different post-anthesis temperature regimes

2017 ◽  
Vol 42 (1) ◽  
pp. 53-65
Author(s):  
Mohammed Humayun Kabir ◽  
Qing Liu ◽  
Yi Su ◽  
Zhigang Huang ◽  
Langtao Xiao
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Indica Rice ◽  
Grain Filling ◽  
Flag Leaves ◽  
Content Ratio ◽  
Temperature Regimes ◽  
Head Rice ◽  
Grain Filling Period ◽  
Early Indica Rice

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

Control of Grain Yield by Sink Capacity and Assimilate Supply in Various Rice (Oryza sativa) cultivars

1991 ◽  
Vol 27 (2) ◽  
pp. 127-135 ◽  
Author(s):  
S. Fukai ◽  
L. Li ◽  
P. T. Vizmonte ◽  
K. S. Fischer
Keyword(s):  
Oryza Sativa ◽  
Grain Yield ◽  
Grain Filling ◽  
Grain Weight ◽  
Rice Cultivars ◽  
Sink Capacity ◽  
Single Grain ◽  
Grain Filling Period

SummaryThe objective of this study was to identify whether grain yield in four contrasting rice cultivars is limited by supply of assimilate to fill the grains or by sink capacity to accept the assimilate. Grain yield was limited mostly by sink capacity, with little variation in single grain weight among cultivars, but an old cultivar showed some ability to adjust single grain weight. Sink capacity was very sensitive to variation in assimilate supply immediately after anthesis. Reduction in assimilate supply in the anthesis to early grain filling period reduced filled grain percentage and grain yield, particularly in high yielding cultivars with a large number of grains per panicle.

scholarly journals Earliness, spike productivity and protein content in European winter wheat landraces and obsolete cultivars

2011 ◽  
Vol 49 (No. 2) ◽  
pp. 67-74 ◽  
Author(s):  
L. Dotlačil ◽  
J. Hermuth ◽  
Z. Stehno
Keyword(s):  
Winter Wheat ◽  
Protein Content ◽  
Crude Protein ◽  
Grain Filling ◽  
Grain Weight ◽  
Crude Protein Content ◽  
European Winter Wheat ◽  
Wheat Landraces ◽  
Grain Filling Period ◽  
Obsolete Cultivars

European winter wheat landraces and obsolete cultivars (121 accessions in set I and 101 accessions in set II) with modern check cultivars were evaluated in three-year field trials. Increased spike productivity in modern cultivars could be attributed mainly to increased number of grains in spikelet and increased HI, whereas TGW has marginal effect. Old cultivars had on average by 2–3% higher crude protein content in grain than modern ones. Among selected 10 characters, relatively wide diversity (C.V. 11–20%) has been estimated in spike length and characters of spike productivity (except of grain weight with C.V. close to 9%). It was difficult to distinguish the cultivars according to the country of origin, however, earliness and lower spike productivity seems to be characteristic for South-East origin whereas cultivars from North-West Europe showed opposite characters. Correlation analyses showed close relations between earliness in heading and in maturity and negative relation between late heading and grain filling period, which was positively correlated with TGW and HI (r = 0.26 to 0.38). Number of grains in spikelets was highly correlated with spike productivity and HI (r = 0.62 to 0.69) whereas relations between these two characters and TGW were lower (r = 0.20 to 0.51). Spike productivity characters, except of TGW, are in negative correlation with crude protein content in grain (r = –0.34 to –0.50). Regression analyses confirmed that main determining character for the spike productivity is number of kernels in spikelet (about 40% of variation) while effects of TGW are about half-size. Crude protein content was positively affected by plant height (15–30% of variation) impact of grain weight per spike was lower (14–17% of variation) and negative. Potentially valuable donors of earliness and longer grain filling period were identified for further studies and/or utilization in breeding programs. As especially valuable character can be considered very high crude protein content (around 18% in cvs Berg-land, Ukrajinka, Sippbachzeller, Innichen Nr. 25001 and Barbu du Finistre). High crude protein content combined with relatively good spike productivity and/or long grain filling period or earliness was found in cvs Visperterminen 640 E, Hatvan, Szekacz 1242, Berchtesgardener Vogel, Ble du Lot and Barbu du Finistere.

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
Keyword(s):  
High Temperature ◽  
Reproductive Development ◽  
Grain Filling ◽  
Triticum Aestivum L ◽  
High Temperature Stress ◽  
Grain Weight ◽  
Threshold Temperature ◽  
Temperature Regimes ◽  
Crop Development ◽  
Significant Yield

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.

Grain-filling of superior spikelets and inferior spikelets for japonica rice under low-amplitude warming regime in lower reaches of Yangtze River Basin

2021 ◽  
pp. 1-10
Author(s):  
Zhi Dou ◽  
Haixiang Zhang ◽  
Wenzhu Chen ◽  
Ganghua Li ◽  
Zhenghui Liu ◽  
...  
Keyword(s):  
Elevated Temperature ◽  
River Basin ◽  
Yangtze River ◽  
Yangtze River Basin ◽  
Grain Filling ◽  
Grain Weight ◽  
Sink Strength ◽  
Filling Rate ◽  
Grain Filling Period ◽  
Grain Filling Stage

Abstract Grain-filling, as the final growth stage of rice, is sensitive to environmental temperature change. Previous studies mainly concerned about the effects of high temperature stress during grain-filling on rice growth, and most experiments were carried out with pot for cultivating rice and greenhouse for warming. This research investigated the response of rice grain-filling of superior spikelets (SS) and inferior spikelets (IS) of two japonica cultivars to elevated temperature during grain-filling stage under open-field warming conditions in lower reaches of Yangtze River Basin using free-air temperature enhancement facility. Results indicated that rice yield was not significantly changed by warming less than 4°C. SS and IS showed different responses to elevated temperature during the grain-filling stage, whereas there were similar trends between two cultivars and years. For SS, although elevated temperature enhanced its filling rate during the early grain-filling period, and caused a shorter grain-filling period and a lighter grain weight; for IS, elevated temperature improved its grain weight by enhancing its filling rate during middle and late grain-filling period due to the increased number of days with suitable temperature. For both SS and IS, key starch biosynthesis enzymes and indole-3-acetic acid content exhibited generally a similar dynamics trend with grain-filling rates, and these sink strength parameters presented higher levels under elevated temperature relative to natural temperature for IS during middle and late grain-filling period. Consequently, warming less than 4°C presented different influences on SS and IS; the improvement of IS filling under warming regime was associated with the intensification of grain sink strength.

Final grain weight in wheat as affected by short periods of high temperature during pre- and post-anthesis under field conditions

1999 ◽  
Vol 26 (5) ◽  
pp. 453 ◽  
Author(s):  
Roxana Savin ◽  
Daniel F. Calderini ◽  
Gustavo A. Slafer ◽  
Leonor G. Abeledo
Keyword(s):  
High Temperature ◽  
Grain Filling ◽  
Sowing Date ◽  
Temperature Treatment ◽  
Grain Weight ◽  
Field Conditions ◽  
High Temperature Treatment ◽  
Sowing Dates ◽  
Grain Filling Period ◽  
Response To Temperature

Individual grain weight is an important source of variation for grain yield in wheat. The aim of this study was to investigate the effect of short periods of high temperature immediately pre-anthesis, or during post-anthesis, on grain weight under field conditions. Thus, two wheat cultivars of different grain weight potential were sown on four different sowing dates to provide different temperature conditions during the pre- and post-anthesis periods. In addition, for two sowings, acrylic boxes were installed to increase spike temperature either immediately before anthesis, or during the lineal phase of the grain-filling period. Final grain weight was significantly affected by sowing date, genotype and grain position on the spike. Grain weight showed a clear relationship with the average temperature of the grain filling period, but this relationship was either linear or curvilinear, depending on the cultivar. Both high temperature treatments, i.e. at pre- or post-anthesis, significantly diminished final grain weight, and their effect was similar with the exception of heavier grains, which were unresponsive to the high temperature treatment at pre-anthesis. Finally, a better understanding of final grain weight was reached when temperatures from the pre-anthesis period were included in the analysis of grain weight response to temperature.

scholarly journals Grain filling patterns of barley as affected by high temperature stress

2017 ◽  
Vol 15 (2) ◽  
pp. 174-181
Author(s):  
Md Rasel Rana ◽  
Md Masudul Karim ◽  
Md Juiceball Hassan ◽  
Md Alamgir Hossain ◽  
Md Ashraful Haque
Keyword(s):  
Heat Stress ◽  
Grain Yield ◽  
Grain Filling ◽  
High Temperature Stress ◽  
Water Soluble ◽  
Grain Weight ◽  
Soluble Carbohydrates ◽  
Barley Cultivars ◽  
The Mean ◽  
Grain Filling Period

Grain filling determines the grain weight, a major component of grain yield in cereals. Grain filling in barley depends on current assimilation and culm reserves (mainly water-soluble carbohydrates). Nowadays barley is facing heat stress problem which is mostly responsible to reduce the yield of barley. A field experiment was conducted at the Field Lab, Department of Crop Botany, BangladeshAgriculturalUniversity, Mymensingh during November 2015 to March 2016 to study the grain filling patterns and the contributions of culm reserves to grain yield under heat stress. The experiment consisted of two factors—barley cultivars and heat stress. The heat stress was imposed by late sowing. The tillers were sampled once a week during grain filling period to determine the changes in dry weights of different parts, viz., leaves, culm with sheath, spikes, and grains; and to examine the contribution of culm reserves to grain yield. The results in the experiment revealed that the grain yield was reduced by 22-28% due to the stress. The grain yield varied from 52 to 150 g m−2 with the mean of 102 g m−2 under control while it varied from 37 to 116 g m−2 with the mean of 75 g m−2 under heat stress. Among the cultivars studied BARI Barley5, BARI Barley2 and BARI Barley1, seemed as high yielders while BARI Barley3, BARI Barley4, BARI Barley6 as the low yielders under heat stress treatment. The reduction in grain yield was attributable mainly to lighter grain weight due to the stress. Heat stress drastically reduced the grain filling duration by 45–50%. However, the stress increased the grain filling rate by 6–53%. The amount of reserves remobilized to grain varied among the cultivars ranging from 4.8 to 12.77 mg spike−1 in control and from 1.73 to 6.25 mg spike−1 in stressed plants. The stressed barley plants exhibited lower accumulation of reserves in culm but they showed almost its complete remobilization to the grain. The contribution of culm reserves to grain yield varied from 1.13 to 19.52%, and 1.09 to 2.11% in control and in stressed plants, respectively. In conclusion, culm reserve is the important attributes in grain yield in Bangladeshi barley cultivars but the contribution remains almost unaffected due the post-anthesis heat stress.J. Bangladesh Agril. Univ. 15(2): 174-181, December 2017

Methodological aspects and impact on grain weight of source reduction through shade meshes during grain filling of bread wheat

2020 ◽  
Vol 71 (8) ◽  
pp. 739
Author(s):  
Maria L. Maydup ◽  
Mariana Antonietta ◽  
Nicolás Rouillet ◽  
Maria G. Cano ◽  
Juan J. Guiamet ◽  
...  
Keyword(s):  
Bread Wheat ◽  
Photosynthetic Activity ◽  
Light Attenuation ◽  
Grain Filling ◽  
Triticum Aestivum L ◽  
Grain Weight ◽  
Light Transmittance ◽  
Source Reduction ◽  
Grain Filling Period ◽  
Days After Anthesis

In crop studies, shading is a common approach for reducing source activity (i.e. assimilates produced by photosynthesis); however, if source reduction is not directly proportional to the degree of light attenuation, estimations could be flawed. We analysed the effects of shading at three levels on light transmittance, air and canopy temperatures, and actual photosynthetic activity at different times of day, and on grain weight in a modern genotype of bread wheat (Triticum aestivum L.). The treatments were imposed 10 days after anthesis and comprised three levels of shading with meshes: 80%, 50% and 10% transmittance during midday. The decrease in midday photosynthetic activity (electron transport rate, ETR; and CO2 assimilation, An) in the shading treatments compared with control plants did not fit a 1:1 relationship with light transmittance of the meshes; for example, the reduction in ETR and An was <50% under the mesh with 50% light transmittance. The decrease in light transmittance and photosynthesis caused by the meshes was higher during the morning and afternoon than midday. In the grain-filling period, midday ETR showed a progressive, age-dependent decrease in control plants compared with shading treatments. Initial differences in photosynthetic activity between treatments were attenuated throughout the grain-filling period. The diurnal course of air temperature showed a progressive decrease from control to shade treatments, mainly during midday. This pattern was confirmed by infrared thermometry of canopy temperature, with severe shade showing the lowest temperature. Greenness measurements at 19 days after anthesis showed delayed senescence in shaded plants, possibly due to the decrease in temperature under shade. Grain weight per ear was reduced in shading treatments (mainly with 50% and 10% light transmittance). The decrease in grain weight per ear plotted against the decrease in photosynthesis (evaluated through ETR or An) did not fit a 1:1 relationship. This could be explained in part by an observed increase in dry matter retranslocation from the stem. In summary, estimations of source reduction on the basis of light attenuation could be biased, because the photosynthesis decrease is less than proportional, and photosynthesis differences are attenuated throughout grain filling.

Response of barley genotypes to terminal soil moisture stress: phenology, growth, and yield

2007 ◽  
Vol 58 (1) ◽  
pp. 29 ◽  
Author(s):  
Agueda González ◽  
Isaura Martín ◽  
Luis Ayerbe
Keyword(s):  
Water Stress ◽  
Yield Components ◽  
Agronomic Traits ◽  
Central Area ◽  
Grain Filling ◽  
Stress Conditions ◽  
Grain Weight ◽  
Growth And Yield ◽  
High Yield ◽  
Grain Filling Period

Terminal drought is the main factor limiting the yield of cereals in the central area of Spain because rainfall is scarce and temperatures are high during the grain-filling period. The response of 12 cultivated barley (Hordeum vulgare L.) genotypes consisting of 6 breeding lines showing high yield under terminal water stress and 6 commercial varieties was studied in a rain shelter. Trials were performed over 3 years to determine the influence of terminal water stress on yield and yield components and the relationship between yield and phenological and agronomic traits. When the crop reached the flag-leaf stage, half of the experimental plots were subjected to a water-stress treatment and the remainder were maintained at optimal water conditions. Variations were observed in number of days to ear emergence, days to maturity, and length of grain-filling period. Precocity strongly influenced the length of the grain-filling period so that the earlier genotypes had the longest grain-filling periods. Among yield components, mean grain weight had the greatest influence on yield under terminal water stress conditions. Earliness and length of grain-filling period were the phenological traits that most influenced yield in water stress conditions. These traits and harvest index (HI) showed a significant correlation (P < 0.001) with grain yield. Earliness, mean grain weight, and HI contributed to greater yields under terminal water stress.

scholarly journals Screening of barley genotypes for drought tolerance based on culm reserves contribution to grain yield

2018 ◽  
Vol 16 (1) ◽  
pp. 62-66
Author(s):  
Md Masudul Karim ◽  
Md Amirul Islam ◽  
Md Rasel Rana ◽  
Md Alamgir Hossain ◽  
Md Abdul Kader
Keyword(s):  
Drought Stress ◽  
Grain Yield ◽  
Grain Filling ◽  
Water Soluble ◽  
Grain Weight ◽  
Soluble Carbohydrates ◽  
Barley Cultivars ◽  
Two Factors ◽  
Grain Filling Period ◽  
Ripe Stage

Grain filling determines the grain weight, a major component of grain yield in cereals. Grain filling in barley depends on current assimilation and culm reserves. A pot experiment was conducted at the Grilled House, Department of Crop Botany, Bangladesh Agricultural University, Mymensingh during October 2015–May 2016 to study the grain filling patterns and the contributions of culm reserves to grain yield under drought stress. The experiment consisted of two factors—barley cultivars (six cultivars) and drought stress treatments (control and drought stress). Drought stress was imposed by limiting the irrigation during grain filling period. The tillers were sampled at anthesis, milk-ripe and maturity to determine the changes in dry weights of different parts, viz., leaf lamina, culm with sheath, spikes, and grains; and to examine the contribution of culm reserves to grain yield. The result in this experiment revealed that the grain yield was reduced by 5–25% due to drought stress. The reduction in grain yield was attributable to reduce number of grains per spike and lighter grain weight due to the stress. Drought stress drastically reduced the grain filling duration by about 30% and the stress induced early leaf senescence. Photosynthesis rate and leaf greenness were also reduced in stress. The stress altered the contribution of culm reserves, water soluble carbohydrates (WSCs) in culms to grains. At milk ripe stage, accumulation reached its peak. It accumulated 29.0 to 70.0 mg and from 15.8 to 40.6 mg culm−1 in control and stressed plants, respectively. The residual culm WSCs ranged from 3.5 to 11.2 mg and 1.0 to 3.5 mg culm−1 under control and stress conditions, respectively. The highest contribution of culm WSCs to grain yield was observed in BARI barley2 and the lowest was in BARI barley5 both in control and stress condition. Among the cultivars studied, BARI barley2 produced higher yield with the higher contribution of culm reserves to grain yield under the drought stress.J. Bangladesh Agril. Univ. 16(1): 62-66, April 2018

Sign in / Sign up

Export Citation Format

Share Document