Some effects of heat waves on grain sorghum at the stage of head emergence

1969 ◽  
Vol 9 (41) ◽  
pp. 636 ◽  
Author(s):  
D Pasternak ◽  
GL Wilson

Sorghum plants were exposed at head emergence to simulated heat waves for five days, and subsequent grain production observed. Comparisons were made between relatively dry heat (108�F, 41 per cent RH by day and 90�F, 53 per cent RH by night), more humid hot conditions (107�F, 70 per cent RH-90�F, 70 per cent RH), and ambient (81�F, 64 per cent RH-71�F, 85 per cent RH). Whole inflorescences or portions that had emerged before heat application were little affected, whereas most enclosed flowers were killed. High temperature was responsible, humidity having little effect. Grain yield depended on the resulting number of grains. There was some loss of pollen viability in the dry heat treatments, but not sufficient to affect seed set.

Plant Disease ◽  
2010 ◽  
Vol 94 (12) ◽  
pp. 1469-1475 ◽  
Author(s):  
Rebecca S. Bennett ◽  
Patrick D. Colyer

The potential of low- and high-temperature dry heat, and hot water treatments, for disinfesting cottonseed of Fusarium oxysporum f. sp. vasinfectum was investigated. Naturally infected seeds from Louisiana were air-heated at 30, 35, and 40°C for up to 24 weeks. Seed harvested from bolls inoculated with race 4 of F. oxysporum f. sp. vasinfectum were incubated in dry heat at 60, 70, and 80°C for 2 to 14 days, or were immersed in 90°C water from 45 s to 3 min. The effects on seed germination and vigor of hot water treatment and a subset of the high-temperature dry heat treatments were also examined in seeds of a Pima (Gossypium barbadense) and an Upland (G. hirsutum) cultivar. Low- or high-temperature dry heat did not eliminate Fusarium spp. from the seed, although seed infection declined more rapidly with higher incubation temperatures. High-temperature dry heat treatments effective in eliminating fusaria also significantly reduced seed vigor in both the Pima and Upland cultivars. Seed from all times of immersion in hot water were less frequently infected with Fusarium spp. than nontreated seed. Incidence of seed infection did not differ significantly among immersion times ranging from 75 s to 3 min. Immersion in 90°C water did not reduce germination or vigor at exposure times ≤120 s and ≤150 s for seeds of Pima and Upland cotton, respectively. Results from the hot water treatments suggest that thermotherapy may be optimized to provide a tactic to prevent the spread of virulent F. oxysporum f. sp. vasinfectum genotypes into uninfested areas through infected seed.


2020 ◽  
Author(s):  
Qiuqian Hu ◽  
Kehui Cui ◽  
Wencheng Wang ◽  
Qifan Lu ◽  
Jianliang Huang ◽  
...  

Abstract Background: Decreased spikelet fertility is often responsible for reduction in grain yield in rice (Oryza sativa L.). In this study, two varieties with different levels of heat tolerance, Liangyoupeijiu (LYPJ, heat susceptible) and Shanyou63 (SY63, heat tolerant) were subjected to two temperature treatments for 28 days during the panicle initiation stage in temperature/relative humidity-controlled greenhouses: high temperature (HT; 37/27℃; day/night) and control temperature (CK; 31/27℃; day/night) to investigate changes in anther development under HT during panicle initiation and their relationship with spikelet fertility.Results: HT significantly decreased the grain yield of LYPJ by decreasing the number of spikelets per panicle and seed setting percentage. In addition, HT produced minor adverse effects in SY63. The decreased spikelet fertility was primarily attributed to decreased pollen viability and anther dehiscence, as well as poor pollen shedding of the anthers of LYPJ under HT. HT resulted in abnormal anther development (fewer vacuolated microspores, un-degraded tapetum, unevenly distributed Ubisch bodies) and malformation of pollen (obscure outline of the pollen exine with a collapsed bacula, disordered tectum, and no nexine of the pollen walls, uneven sporopollenin deposition on the surface of pollen grains) in LYPJ, which may have lowered pollen viability. Additionally, HT produced a compact knitted anther cuticle structure of the epidermis, an un-degraded septum, a thickened anther wall, unevenly distributed Ubisch bodies, and inhibition of the confluent locule, and these malformed structures may be partially responsible for the decreased anther dehiscence rate and reduced pollen shedding of the anthers in LYPJ. In contrast, the anther wall and pollen development of SY63 were not substantially changed under HT. Conclusions: Our results suggest that disturbed anther walls and pollen development are responsible for the reduced spikelet fertility and grain yield of the tested heat susceptible variety, and noninvasive anthers and pollen formation in response to HT were associated with improved heat tolerance.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Qiuqian Hu ◽  
Wencheng Wang ◽  
Qifan Lu ◽  
Jianliang Huang ◽  
Shaobing Peng ◽  
...  

Abstract Background Decreased spikelet fertility is often responsible for reduction in grain yield in rice (Oryza sativa L.). In this study, two varieties with different levels of heat tolerance, Liangyoupeijiu (LYPJ, heat susceptible) and Shanyou63 (SY63, heat tolerant) were subjected to two temperature treatments for 28 days during the panicle initiation stage in temperature/relative humidity-controlled greenhouses: high temperature (HT; 37/27 °C; day/night) and control temperature (CK; 31/27 °C; day/night) to investigate changes in anther development under HT during panicle initiation and their relationship with spikelet fertility. Results HT significantly decreased the grain yield of LYPJ by decreasing the number of spikelets per panicle and seed setting percentage. In addition, HT produced minor adverse effects in SY63. The decreased spikelet fertility was primarily attributed to decreased pollen viability and anther dehiscence, as well as poor pollen shedding of the anthers of LYPJ under HT. HT resulted in abnormal anther development (fewer vacuolated microspores, un-degraded tapetum, unevenly distributed Ubisch bodies) and malformation of pollen (obscure outline of the pollen exine with a collapsed bacula, disordered tectum, and no nexine of the pollen walls, uneven sporopollenin deposition on the surface of pollen grains) in LYPJ, which may have lowered pollen viability. Additionally, HT produced a compact knitted anther cuticle structure of the epidermis, an un-degraded septum, a thickened anther wall, unevenly distributed Ubisch bodies, and inhibition of the confluent locule, and these malformed structures may be partially responsible for the decreased anther dehiscence rate and reduced pollen shedding of the anthers in LYPJ. In contrast, the anther wall and pollen development of SY63 were not substantially changed under HT. Conclusions Our results suggest that disturbed anther walls and pollen development are responsible for the reduced spikelet fertility and grain yield of the tested heat susceptible variety, and noninvasive anthers and pollen formation in response to HT were associated with improved heat tolerance.


2021 ◽  
Vol 8 (03) ◽  
pp. 154-160
Author(s):  
Tran Loc Thuy ◽  
Tran Ngoc Thach ◽  
Tran Thi Thanh Xa ◽  
Chau Thanh Nha ◽  
Vo Thi Tra My ◽  
...  

Environmental stress trigger a variety of rice plant response, ranging from alters seed set, grain yield and grain quality during flowering and grain filling stage.  Efforts are required to improve our understanding of the impact of heat stress on rice production, which are essential strategies in rice cultivation. This article investigated the seed set, yield components and grain yield of Vietnamese rice cultivars (Indica germplasm) under high temperature environment during the flowering and grain filling stage. Six rice cultivars, including popular cultivars and new cultivars of Cuu Long Delta Rice Research Institute, and one popular extraneous cultivar with differences in maturing time, were grown in pots at high temperature (HT) and natural temperature condition as control (CT). All rice cultivars were subjected to the high temperature starting from the heading stage to the harvest maturity, applied by greenhouse effect. The greenhouse has about 25 cm window opening on 3 sides for air ventilation. The seed set rate of the heat-sensitive rice genotypes decreased significantly under HT, leading to a significant reduction in grain yield. The lowest seed set was recorded in “OM4900” (44.3%) and “OM18” (39.9%) under high temperature environment. The lower yield in all rice cultivars at an elevated temperature resulted in a dramatic decrease of filled grains and contributed to a loss of 1000-grain weight. ‘“OM892” is a potential rice cultivar for heat tolerant breeding program due to the seed set percentage was above 80% in both HT and CT conditions. High temperature during the grain filling stage resulted in a decreased amylose and increased chalkiness for all OM cultivars.


2013 ◽  
Vol 40 (5) ◽  
pp. 439 ◽  
Author(s):  
Chuc T. Nguyen ◽  
Vijaya Singh ◽  
Erik J. van Oosterom ◽  
Scott C. Chapman ◽  
David R. Jordan ◽  
...  

Sorghum (Sorghum bicolor (L.) Moench) is grown as a dryland crop in semiarid subtropical and tropical environments where it is often exposed to high temperatures around flowering. Projected climate change is likely to increase the incidence of exposure to high temperature, with potential adverse effects on growth, development and grain yield. The objectives of this study were to explore genetic variability for the effects of high temperature on crop growth and development, in vitro pollen germination and seed-set. Eighteen diverse sorghum genotypes were grown at day : night temperatures of 32 : 21°C (optimum temperature, OT) and 38 : 21°C (high temperature, HT during the middle of the day) in controlled environment chambers. HT significantly accelerated development, and reduced plant height and individual leaf size. However, there was no consistent effect on leaf area per plant. HT significantly reduced pollen germination and seed-set percentage of all genotypes; under HT, genotypes differed significantly in pollen viability percentage (17–63%) and seed-set percentage (7–65%). The two traits were strongly and positively associated (R2 = 0.93, n = 36, P < 0.001), suggesting a causal association. The observed genetic variation in pollen and seed-set traits should be able to be exploited through breeding to develop heat-tolerant varieties for future climates.


1996 ◽  
Vol 74 (1) ◽  
pp. 40-45 ◽  
Author(s):  
A. R. Lansac ◽  
C. Y. Sullivan ◽  
B. E. Johnson

Suboptimal temperatures cause grain yield reductions generally associated with low seed-set in sorghum [Sorghum bicolor (L.) Moench]. Low proline concentration in pollen has been associated with cold-induced male sterility. This study was done to (i) determine free proline concentrations in grain sorghum pollen after low temperature exposure, (ii) determine the relationship between seed-set and proline concentration in pollen, and (iii) determine the association of proline concentration in pollen with grain yield in sorghums of different maturity. Eleven sorghum genotypes, grown in a greenhouse at 27/22 °C (day/night) until the early boot stage were transferred to 20/10 °C in growth chamber until physiological maturity. Concentration of proline in pollen was determined at anthesis and related to seed number and grain yield. Proline concentrations in pollen increased from 19 to 36 μg∙mg−1 fresh wt. to 30 to 49 μg∙mg−1 fresh wt. at low temperatures. Seed number and grain yield were reduced by low temperature in most of the genotypes. Percent seed-set in male sterile lines was significantly correlated (r = 0.45**) with free proline concentrations in the pollen from 13 fertile hybrids grown under cold or control conditions. Higher concentrations of proline in pollen under cool and also control temperatures seemingly contribute to greater pollen viability in grain sorghum. In 21 sorghum hybrids grown under control temperatures, seed number per panicle was found correlated (r = 0.42*) to free proline concentrations in pollen. Genotypic differences in pollen proline concentration were not associated with differences between maturity groups. Keywords: Sorghum bicolor (L.) Moench, pollen, free proline, low temperatures, seed-set, grain yield.


Jurnal BiBieT ◽  
2016 ◽  
Vol 1 (1) ◽  
pp. 9
Author(s):  
Dewi Rezki

<p align="center"><strong>ABSTRAK</strong></p><p align="center"><strong> </strong></p><p>Tingginya laju pertumbuhan penduduk dan alih fungsi lahan pertanian, menyebabkan perlunya dilakukan upaya untuk meningkatkan produksi beras. Sedangkan produksi yang diperoleh dari lahan pertanian yang ada belum mencapai hasil yang optimal.  Upaya yang perlu dilakukan  untuk meningkatkan produksi padi diantaranya adalah memperbaiki tingkat kesuburan tanah dan metode budidaya tanaman padi.  Penelitian ini bertujuan untuk memperoleh kombinasi yang paling tepat antara bahan  organik kaya sumber hayati (BOKASHI) dan pupuk NPK terhadap produksi padi yang ditanam secara jajar legowo.  penelitian dilakukan di Kecamatan Pulau Punjung Kabupaten Dharmasraya Provinsi Sumatera Barat pada bulan Juli-Desember 2015.  Penelitian menunjukkan bahwa kombinasi bokashi + 75 % pupuk buatan memberikan hasil gabah 6.3 ton/Ha, sementara produksi padi tanpa penambahan bokashi + 100 % pupuk buatan memberikan hasil gabah 3.9 ton/Ha, dengan demikian dapat disimpulkan bahwa penambahan bokashi dapat meningkatkan produksi gabah sebanyak 2.4 ton/Ha.  Penambahan 2 ton/Ha bokashi yang ditanam secara sistem jajar legowo pada tanaman padi berpengaruh nyata terhadap pertumbuhan dan produksi tanaman padi dan dapat mengurangi penggunaan pupuk buatan sebanyak 25 %.</p><p>Kata Kunci : Bokashi, Produksi Padi, Jajar Legowo, Kombinasi</p><p> </p><p align="center">ABSTRACT</p><p align="center"> </p><p>The high rate of population growth and the conversion of agricultural land, causing the need for efforts to increase rice production. While the production obtained from existing agricultural lands yet to achieve optimal results. Efforts should be made to increase the rice production of which is to improve soil fertility and method of rice cultivation. This study aims to obtain the most appropriate combination of organic material rich in biological resources (Bokashi) and NPK fertilizer on rice production are grown Legowo row. Research conducted in the District Pulau Punjung Dharmasraya West Sumatra province in July to December 2015. The study showed that the combination of Bokashi + 75% of artificial fertilizers provide grain yield of 6.3 tonnes / ha, while rice production without adding Bokashi + 100% synthetic fertilizers provide grain yield 3.9 tonnes / ha, thus it can be concluded that the addition of bokashi can increase grain production as much as 2.4 tons / ha. Addition of 2 tons / ha planted Bokashi system Legowo row in rice plants significantly affect the growth and production of rice plants and can reduce the use of artificial fertilizers as much as 25%.</p><p>Keywords: Bokashi, Rice Production, Jajar Legowo, Combination</p>


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