The effect of heat stress on quinoa (cv. Titicaca) under controlled climatic conditions

AbstractQuinoa (Chenopodium quinoa Willd.) is capable of adapting to multiple environments and tolerating abiotic stresses including saline, drought and frost stress conditions. However, the introduction of quinoa into new environments has disclosed adaptation challenges. The principle factor affecting crop pollination is heat stress at flowering, which leads to sterile plants. To investigate the effect of high temperatures during the sensitive phenological phases, flowering and seed germination, a Danish-bred cultivar (cv. Titicaca) was grown in climatic chambers. Selection of the cv. Titicaca was based on the fact that it is the most extensively used cultivar in the Sahel and Middle East and North African region. The results of this research demonstrated that temperatures exceeding 38 °C hindered seed germination and pollination, and therefore, seed yield at harvest. At 38 °C, seed yield losses were 30%, whilst seed germination percentage declined below 50%. In addition, the results of the present research were compared with field observations from Burkina Faso in order to determine the spatiotemporal suitability of this crop with respect to temperature stress. Although many other abiotic stresses need to be considered when defining crop calendars (e.g. heavy precipitation in July and August), this research proposes the following growing periods to avoid heat-stress conditions at flowering: Sahel (July–September and November–February), Soudano–Sahel (June–February) and Soudanian zone (all year round).

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INFLUENCE DES CULTIVARS ET DES STADES DE PRÉLÈVEMENT DE LA PREMIÈRE POUSSE SUR LA PRODUCTION DE SEMENCE DE TRÈFLE ROUGE

Canadian Journal of Plant Science ◽

10.4141/cjps90-129 ◽

1990 ◽

Vol 70 (4) ◽

pp. 1071-1080 ◽

Cited By ~ 1

Author(s):

LUCIUS BELZILE

Keyword(s):

Seed Germination ◽

Seed Production ◽

Seed Yield ◽

Trifolium Pratense ◽

Red Clover ◽

Kernel Weight ◽

Climatic Conditions ◽

Cultivar Group ◽

Stage Of Development ◽

Clover Seed

For five years, the effect of cultivars and vegetative stage of cutting were measured on red clover (Trifolium pratense L.) seed production. The first group of cultivars included Hungaropoli, Ottawa and Lakeland harvested in 1981 and 1982. The second group included Arlington, Florex and Prosper I harvested in 1984, 1985 and 1987. The total annual seed yield differed within cultivars and the highest seed yield was obtained with Hungaropoly and Florex. In the first cultivar group, the tetraploid Hungaropoly obtained a kernel weight higher than the diploids Lakeland and Ottawa. In the second group of cultivars, all diploids, Arlington yielded the highest kernel weight. The percentage of seed germination of Hungaropoly was higher than Lakeland and Ottawa while for Florex it was slightly higher than Arlington and Prosper I. A prior vegetative cutting is essential for good seed yield. In the absence of vegetative cutting seed weight seemed improved. The stage of development at which vegetative cutting is done has little influence on percentage seed germination. These results have shown that despite the strong effect of climatic conditions on seed production, the choice of the optimum stage for vegetative cutting and a well adapted cultivar are important aspects in successful seed production.Key words: Red clover, seed production, cultivar, stage of cutting

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Enzyme activity in the micropylar region of Melanoxylon brauna Schott seeds during germination under heat stress conditions

Journal of Seed Science ◽

10.1590/2317-1545v42229988 ◽

2020 ◽

Vol 42 ◽

Author(s):

Marcone Moreira Santos ◽

Eduardo Euclydes de Lima e Borges ◽

Glauciana da Mata Ataíde ◽

Raquel Maria de Oliveira Pires ◽

Debora Kelli Rocha

Keyword(s):

Enzyme Activity ◽

Heat Stress ◽

Seed Germination ◽

Pectin Methylesterase ◽

Stress Conditions ◽

Southeastern Brazil ◽

Experimental Conditions ◽

Mannanase Activity ◽

Ecological Importance ◽

The Many

Abstract: Recent studies indicate that global temperatures will rise substantially in the 21st century, leading to the extinction of several plant species, as plant metabolism and germination are greatly affected by temperature. Melanoxylon brauna, a tree species native to the Atlantic Forest that occurs from northeastern to southeastern Brazil, is one of the many species threatened by global warming. Despite the economic and ecological importance of M. brauna, studies investigating the influence of heat stress on seed germination and biochemical responses are still incipient. This study aimed to evaluate enzyme activity in the micropylar region of M. brauna seeds during germination under heat stress conditions. Endo-β-mannanase, α-galactosidase, polygalacturonase, pectin methylesterase, pectin lyase, total cellulase, 1,3-β-glucosidase, and 1,4-β-glucosidase activities were determined in micropyles of seeds imbibed for 24, 48 and 72 h at 25, 35 and 45 °C. Seed germination was highest at 25 °C. Endo-β-mannanase activity was not detected under any of the experimental conditions, but imbibition temperature had a significant effect on the activity of all other enzymes.

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Effects of Environmental Stresses (Heat, Salt, Waterlogging) on Grain Yield and Associated Traits of Wheat under Application of Sulfur-Coated Urea

Agronomy ◽

10.3390/agronomy11112340 ◽

2021 ◽

Vol 11 (11) ◽

pp. 2340

Author(s):

Adil Altaf ◽

Xinkai Zhu ◽

Min Zhu ◽

Ma Quan ◽

Sana Irshad ◽

...

Keyword(s):

Salt Stress ◽

Heat Stress ◽

Crop Yield ◽

Abiotic Stresses ◽

Climatic Conditions ◽

Growth And Yield ◽

Release Time ◽

Wheat Crop ◽

Spad Value ◽

Coated Urea

Abiotic stresses, such as heat, salt, waterlogging, and multiple-stress environments have significantly reduced wheat production in recent decades. There is a need to use effective strategies for overcoming crop losses due to these abiotic stresses. Fertilizer-based approaches are readily available and can be managed in all farming communities. This research revealed the effects of sulfur-coated urea (SCU, 130 kg ha−1, release time of 120 days) on wheat crops under heat, salt, waterlogging, and combined-stress climatic conditions. The research was done using a completely randomized design with three replicates. The results revealed that SCU at a rate of 130 kg of N ha−1 showed a significantly (p ≤ 0.05) high SPAD value (55) in the case of waterlogging stress, while it was the lowest (31) in the case of heat stress; the control had a SPAD value of 58. Stress application significantly (p ≤ 0.05) reduced the leaf area and was the highest in control (1898 cm2), followed by salt stress (1509 cm2), waterlogging (1478 cm2), and heat stress (1298 cm2). A significantly (p ≤ 0.05) lowest crop yield was observed in the case of heat stress (3623.47 kg ha−1) among all stresses, while it was 10,270 kg ha−1 in control and was reduced up to 35% after the application of heat stress. Among all stresses, the salt stress showed the highest crop yield of 5473.16 kg ha−1. A significant correlation was observed among growth rate, spike length, yield, and physiological constraints with N content in the soil. The SCU fertilizer was the least effective against heat stress but could tolerate salt stress in wheat plants. The findings suggested the feasibility of adding SCU as an alternative to normal urea to alleviate salt stresses and improve wheat crop growth and yield traits. For heat stress tolerance, the applicability of SCU with a longer release period of ~180 days is recommended as a future prospect for study.

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Storage Period and Different Abiotic Factors Regulate Seed Germination of Two Apocynum Species — Cash Crops in Arid Saline Regions in the Northwestern China

Frontiers in Plant Science ◽

10.3389/fpls.2021.671157 ◽

2021 ◽

Vol 12 ◽

Author(s):

Li Jiang ◽

Chaowen She ◽

Changyan Tian ◽

Mohsin Tanveer ◽

Lei Wang

Keyword(s):

Seed Germination ◽

Abiotic Stresses ◽

Arid Regions ◽

Natural Fiber ◽

Abiotic Factors ◽

Light Condition ◽

Storage Period ◽

Germination Percentage ◽

Environmental Benefits ◽

Degraded Land

On degraded land in arid regions, cultivation of Apocynum species can provide significant environmental benefits by preventing soil erosion and desertification. Furthermore, Apocynum venetum and Apocynum pictum, which are mainly distributed in salt-barren lands in the northwestern region of China, are traditionally used to produce natural fiber and herbal tea. Direct sowing of both species may encounter various abiotic stresses such as drought and salinity. However, these effects on germination remain largely unknown, especially for seeds with different storage periods. The aim of this study was to evaluate the effects of storage period, light condition, temperature regime, drought, and salinity on germination performances of both species. Germination experiment was carried out in November 2017. There were four replicates for each treatment, and each petri dish contained 25 seeds. The results indicated that prolongation of storage period significantly decreased the germination percentage and velocity, especially under abiotic stresses. Light did not affect seed germination of A. venetum and A. pictum under any conditions. Seeds had better germination performance at 10/25 and 15/30°C than those of seeds incubated at any other temperatures. With the increase of polyethylene glycol (PEG) and salinity concentrations, seed germination for both species gradually decreased, especially for seeds stored for 2 years. Low PEG (0–20%) and salinity concentration (0–200 mM) did not significantly affect germination percentage of freshly matured seeds. However, long-time storage significantly decreased drought and salinity tolerance in A. venetum and A. pictum during germination stage. For saline soils in arid and semi-arid regions, freshly matured seeds or 1-year-stored seeds of both Apocynum species are recommended to be sown by using drip-irrigation in spring.

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Evaluation of the development and yielding potential of Chenopodium quinoa Willd. under the climatic conditions of Europe. Part one: accomodation of Chenopodium quinoa (Willd.) to different conditions

Acta Agrobotanica ◽

10.5586/aa.2008.025 ◽

2012 ◽

Vol 61 (1) ◽

pp. 179-184 ◽

Cited By ~ 1

Author(s):

Krzysztof Gęsiński

Keyword(s):

Seed Yield ◽

Chenopodium Quinoa ◽

Climatic Conditions ◽

European Countries ◽

High Yield ◽

Green Matter ◽

Southern European Countries ◽

Very High ◽

High Seed Yield

Based on the evaluation of selected varieties of <i>Chenopodium quinoa</i>, their requirements were identified; it was shown which varieties demonstrated the best effects in what conditions. It was found that the best varieties for Europe's conditions were E-DK-4-PQCIP and RU-5-PQCIP. E-DK-4-PQCIP variety showed the best effects under the conditions of cluster II which included e.g. Bydgoszcz (Poland) and cluster IV which included Southern European countries (Greece and Italy), while the best effects found in RU-5-PQCIP variety were identified in cluster I which included Sweden. E-DK-4-PQCIP variety in cluster II showed a very high yield of green matter and a mean seed yield, and in cluster IV - a very high seed yield and a high yield of green matter.

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Pre-Germination Treatments, Temperature, and Light Conditions Improved Seed Germination of Passiflora incarnata L.

Agriculture ◽

10.3390/agriculture11100937 ◽

2021 ◽

Vol 11 (10) ◽

pp. 937

Author(s):

Luciana G. Angelini ◽

Clarissa Clemente ◽

Silvia Tavarini

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Large Scale ◽

Seed Quality ◽

Central Italy ◽

Germination Percentage ◽

Climatic Conditions ◽

Added Value ◽

Medicinal And Aromatic Plants ◽

Passiflora Incarnata

Perennial medicinal and aromatic plants (MAPs) may represent interesting, environmentally friendly crops for the Mediterranean environments. Among MAPs, Passiflora incarnata L. (maypop) represents a very promising crop for its wide adaptability to diverse climatic conditions, low input requirements, and high added-value due to its unique medicinal properties. The main problem in P. incarnata large-scale cultivation is the poor seed quality with erratic and low seed germination, due to its apparent pronounced seed dormancy. Therefore, the aim of this work was to investigate different chemical and physical treatments for overpassing seed dormancy and enhancing seed germination rates of P. incarnata. The effects of (i) different pre-germination treatments (pre-chilling, gibberellic acid—GA3, leaching, scarification, non-treated control), (ii) light or darkness exposure, and (iii) temperature conditions (25, 30, and 35 °C constant and 20–30 °C alternating temperatures) have been examined in seed germination percentage and mean germination time of three P. incarnata accessions (F2016, FF2016, and A2016) grown in field conditions in Central Italy. Data showed that the pre-germination treatments generally stimulated faster germination compared to the control, with the best results obtained in the dark and with high temperatures. These findings are useful for the choice of the most suitable seed pre-germination treatment that can facilitate stable, high and agronomically acceptable germination rates in P. incarnata.

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Differential Responses of Dimorphic Seeds and Seedlings to Abiotic Stresses in the Halophyte Suaeda salsa

Frontiers in Plant Science ◽

10.3389/fpls.2021.630338 ◽

2021 ◽

Vol 12 ◽

Author(s):

Hao Zhang ◽

Mingfang Hu ◽

Hongyuan Ma ◽

Li Jiang ◽

Zhenyong Zhao ◽

...

Keyword(s):

Seed Germination ◽

Seedling Growth ◽

Abiotic Stresses ◽

Inhibitory Effect ◽

Germination Percentage ◽

Suaeda Salsa ◽

High Germination ◽

Germination Characteristics ◽

Black Seeds ◽

Germination Traits

The period between seed germination and seedling establishment is one of the most vulnerable stages in the life cycle of annuals in the saline environments. Although germination characteristics of Suaeda salsa seeds have been reported, the comparative germination patterns of dimorphic seeds and seedling growth to different abiotic stresses remain poorly understood. In this study, germination responses of dimorphic seeds to light and temperature were compared. Meanwhile, responses of dimorphic seeds and thereafter seedlings of S. salsa to different concentrations of NaCl and Na2SO4 were also tested. The results showed that the light did not significantly affect germination percentage of brown seeds, but significantly promoted germination of black seeds. Brown seeds could reach high germination percentage over a wide temperature range, however, germination of black seeds gradually increased with the increase of temperature. Brown seeds had higher germination percentage and velocity than black seeds under the same salt conditions. However, black seeds had higher recovery germination than brown seeds when transferred to deionized water. Young seedlings had lower salt tolerance than germinating seeds. At the same concentrations, Na2SO4 had stronger inhibitory effect on seed germination and seedling growth than NaCl. This study comprehensively compared germination traits of dimorphic seeds and seedling growth of S. salsa, and then developed a conceptual model to explain their adaptation to harsh saline environment.

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Trifoliate Orange Seed Germination Enhancing Method in Mid Hill of Nepal

Journal of Nepal Agricultural Research Council ◽

10.3126/jnarc.v5i1.23807 ◽

2019 ◽

Vol 5 ◽

pp. 62-67

Author(s):

Umesh K. Acharya ◽

Roshan Pakka

Keyword(s):

Seed Germination ◽

Open Field ◽

Cold Hardiness ◽

Germination Rate ◽

Sowing Date ◽

Germination Percentage ◽

Climatic Conditions ◽

Trifoliate Orange ◽

Fruit Maturity ◽

Raised Bed

Trifoliate orange seedlings are used as rootstock for citrus crops due to cold hardiness and phytopthora disease tolerance. Nursery owners usually prepare raised bed in open field to sow seeds of trifoliate. The trifoliate seed production in government farms are very low compared to its demand due to limited number of fruiting trees. Further the germination percent in open nurseries are very low. Hence, production of grafted sapling is very much affected by unavailability of rootstock. Therefore, a study was carried out in National Citrus Research Program, Dhankuta to increase germination rate of trifoliate orange in the year 2016 and 2017. Trifoliate seeds were extracted from three stages of fruits (green mature, half yellow and full yellow) and sown at three dates (September 1st week, September 3rd week and October 1st week) at three raised bed (open field, 50-cm low plastic tunnel with or without sides open). The data on percentage seed germination was taken at 35, 50, 65, 90 and 210 days after seed sowing. The fruit maturity had no effect on germination percentage irrespective of sowing date and method of beds used. The date of sowing resulted significantly higher germination at earlier days but there was non-significant effect during final germination count. Plastic tunnel with open sides resulted 80% germination compared to 46% in tunnel side closed nursery. Hence, low plastic tunnel raised bed having open sides is the best option to raise trifoliate seed sown during 1st week of September to 1st week of October in agro-climatic conditions like Dhankuta.

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Impact of zilpaterol hydrochloride and soybean-oil supplementation on intramuscular fat, fatty acid profile and cholesterol concentration in the longissimus muscle of male hair lamb under moderate heat-stress conditions

Animal Production Science ◽

10.1071/an16747 ◽

2018 ◽

Vol 58 (10) ◽

pp. 1932 ◽

Cited By ~ 1

Author(s):

J. L. Dávila-Ramírez ◽

L. Avendaño-Reyes ◽

E. A. Peña-Ramos ◽

T. Y. Islava-Lagarda ◽

U. Macías-Cruz ◽

...

Keyword(s):

Heat Stress ◽

Fatty Acid ◽

Soybean Oil ◽

Negative Impact ◽

Intramuscular Fat ◽

Climatic Conditions ◽

Stress Conditions ◽

Cholesterol Concentration ◽

Control Group ◽

Zilpaterol Hydrochloride

Forty Dorper × Pelibuey crossbred male lambs (31.70 ± 2.30 kg, 4 months of age) were used to evaluate the effect of zilpaterol hydrochloride (ZH; 0 or 10 mg/lamb daily) and soybean-oil (SBO, 0 or 60 g/kg DM) supplementation on intramuscular fat, fatty acid (FA) profiles and cholesterol concentration of their meat. After 34 days, the animals were slaughtered, and their longissimus thoracis muscle was collected. The climatic conditions were of moderate heat stress (average temperature 35.7°C) during the study. Feedlot performance and carcass characteristics were not affected (P > 0.05) by ZH and SBO supplementation. The ZH treatment decreased the intramuscular fat content (by 30.4%), the amount of monounsaturated FA (by 3.5%) and the monounsaturated FA : saturated FA ratio (by 4.9%) compared with the control group. Supplementation with SBO decreased cis FA, C18:1 n-9c and C20:4 n-6, whereas the trans FA and cholesterol concentration increased. ZH use caused a decrease in body fat and intramuscular fat concentration. However, it caused a decrease in total monounsaturated fatty acids, which are among the healthiest fats in terms of the nutritional value of meat. Generally, principal changes in the lipid composition of hair lamb meat under heat-stress conditions were caused by SBO supplementation; however, they would have a minimal negative impact on human health.

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