Physiological and growth responses of potato cultivars to heat stress

Climate warming is subjecting plants to heat stress, which can affect their physiological processes thereby impacting their growth, development, and productivity. Potato (Solanum tuberosum L.) is a staple food worldwide, but potato crops are very sensitive to heat stress. We have studied the effects of heat stress on the leaf chlorophyll content, plant growth, and tuber yield of 55 commercial potato cultivars in clonal tests under heat-stress conditions [HS; 35 °C (day), 28 °C (night)] and control (non-stress) conditions [CK; 22 °C (day), 18 °C (night)]. The potato cultivars varied in their response to heat stress. Overall, heat stress reduced leaf size, increased the SPAD index values for leaf chlorophyll by up to 65%, and increased plant height by 64%, but severely reduced (by 93%) the mass of the largest tuber. The HS:CK SPAD ratios positively correlated with the HS:CK plant height ratio, mass of the largest tuber under heat stress, and the HS:CK ratio for mass of the largest tuber. Potato cultivars displayed a correlated response to heat stress for their leaf chlorophyll content, plant height, and tuber mass. We have identified the most heat-tolerant and heat-susceptible cultivars for these traits. Under heat-stress conditions, potato cultivars tend not to show as much reduction in tuber mass if the plants have greater increases in leaf chlorophyll content and plant height.

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Association of leaf chlorophyll content with the stay-green trait and grain yield in wheat grown under heat stress conditions

Czech Journal of Genetics and Plant Breeding ◽

10.17221/45/2021-cjgpb ◽

2021 ◽

Author(s):

Chandan Roy ◽

Tirthartha Chattopadhyay ◽

Rakesh Deo Ranjan ◽

Wahid Ul Hasan ◽

Abhishek Kumar ◽

...

Keyword(s):

Heat Stress ◽

Grain Yield ◽

Chlorophyll Content ◽

Flag Leaf ◽

Stress Conditions ◽

High Rate ◽

Stay Green ◽

Spad Value ◽

Leaf Chlorophyll ◽

Breeding Programmes

Heat stress is a major production constraint of wheat in South Asia, particularly in the Gangetic plains of India and Bangladesh. The leaf chlorophyll status is a key determinant for a high rate of photosynthesis under stress. The present experiments included 238 genotypes in 2016–2017 and 321 genotypes in 2017–2018 under optimum and under heat stress conditions. Subsequently, a set of 100 genotypes selected on basis of the heat susceptibility index was evaluated in 2018–2019 under heat stress conditions to study the relationship between important physiological traits and yield under stress. A significant correlation of soil plant analysis development (SPAD) value of the two upper leaves with stay-green trait and grain yield indicates the importance of chlorophyll content, both in flag and penultimate leaf, in maintaining leaf areas under greenness (LAUG) and grain yield under heat stress. The SPAD in the flag and penultimate leaf was responsible for 8.8% and 10.9%, respectively, of the variation in grain yield. For the stay-green trait, 8.4% and 7.2 % of the variation was governed by the SPAD value in the flag and penultimate leaf, respectively. These results suggest that, in addition to the flag leaf, the chlorophyll status of the penultimate leaf can be an important criterion for the selection of superior wheat genotypes under heat stress. The genotypes SW-139; SW 108; DWR-F8-35-9-1; NHP-F8-130; DWR-F8-3-1 that maintained a high chlorophyll content in the flag and penultimate leaf can be used further in breeding programmes addressing heat resistance in wheat.

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The Effects of Gibberellic Acid (GA3) Applications on the Physiological Features of Groundnut (Arachis hypogaea L.) under Different Salt (NaCI) Stress Conditions

Legume Research - An International Journal ◽

10.18805/lr-620 ◽

2021 ◽

Author(s):

E. Erbil

Keyword(s):

Salt Stress ◽

Cell Membrane ◽

Membrane Permeability ◽

Chlorophyll Content ◽

Proline Content ◽

Stress Conditions ◽

Cell Membrane Permeability ◽

External Application ◽

Leaf Chlorophyll Content ◽

Leaf Chlorophyll

Background: Salinity is one of the most imperative problems of farmers worldwide. Reports are available that the external application of GA3 can reduce harmful effects of salinity. Low concentration and small quantities of GA3, a phytohormone, is essential to hasten the growth and development of plants. The current study was aimed to test the efficiency of GA3 on the impart of salt tolerance in terms of better nutrient uptake under salt stress situation and to determine the effect of external giberellic acid applications on the physiological properties and proline level of peanuts under different salt (NaCl) stress conditions on the degree of resistance to salt stress in peanuts. Methods: Trial was established as split plot design with 3 replications and NC-7 variety was used as a material. The chlorophyll content in leaves, ion (K, Na, Mg, Ca) content, cell membrane permeability were searched in the research. To determine the physiological responses of groundnut in the conditions of Gibberellic asid (GA3), (0, 5, 15 mM) applications under the different salt (Nacl), (0, 25, 50, 100 mM) stress conditions at the Plant Growth Room in the GAP Agricultural Research Institute in Şanlıurfa, Turkey in 2019. The chlorophyll content in leaves, ion (K, Na, Mg, Ca) content, cell membrane permeability were searched in the research. Result: The increasing salt applications decreases the leaf chlorophyll content and leaf ions (K, Mg, Ca) content, in contrast, increased the cell membrane permeability, proline content and sodium concentration were determined. The gibberallic asid applied externally against salt stress were determined to have the positive effects on traits; leaf chlorophyll content, ion (K, Na, Mg, Ca) content, cell membrane permeability, proline content.

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RESPONSE OF POMEGRANATE " CV. WONDERFUL" TRANSPLANTS TO MINERAL NUTRITION AND GIBBERRELIC ACID

IRAQI JOURNAL OF AGRICULTURAL SCIENCES ◽

10.36103/ijas.v51i1.933 ◽

2020 ◽

Vol 51 (1) ◽

Author(s):

Hamdan & Jomaa

Keyword(s):

Gibberellic Acid ◽

Chlorophyll Content ◽

Plant Height ◽

Mineral Nutrition ◽

Dry Weight ◽

Fresh Weight ◽

Leaf Chlorophyll Content ◽

Leaf Chlorophyll ◽

Engineering Sciences ◽

Leaf Dry Weight

This study was aimed to investigate response of pomegranate " Cv. Wonderful" transplants to mineral nutrition and gibberellic acid, it was conducted at the Coll. of Agriculture Engineering Sciences-University of Baghdad, a factorial experiment was according to R.C.B.D. with three replicates for two consecutive growth seasons 2018-2019 to addition six treatments of nue tharyan fertilizer (N.P.K. 20:20:20 and some micronutrients) with three concentrations (0, 2.5, 5 gm.L-1) for each of the soil fertilization and foliar application, and spraying of gibberellic acid (GA3) with three concentrations (0, 50, 100 mg.L-1), and their interaction. Addition of chemical fertilizer to the soil with highest concentration (5 gm.L-1) was the most effective, where led to a significant increases in average of plant height (66.56, 47.05 cm), leaf chlorophyll content (318.3, 323.9 mg.100 g-1 fresh weight) and leaf dry weight (43.51, 50.20 %) for both seasons, respectively. The average of plant height, leaf chlorophyll content and leaf dry weight were increased when sprayed of GA3 at 100 mg.L-1 which reached (71.18, 52.99 cm), (317.5, 322.8 mg.100g-1 fresh weight) and (43.13, 48.15 %) to this traits for both seasons, respectively. the interaction between two factors showed a different effects between highest and lowest on all the traits for both seasons.

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Timing of Drip Irrigation Initiation Affects Irrigation Water Use Efficiency and Yield of Bell Pepper under Plastic Mulch

HortTechnology ◽

10.21273/horttech.18.3.397 ◽

2008 ◽

Vol 18 (3) ◽

pp. 397-402 ◽

Cited By ~ 7

Author(s):

Mathieu Ngouajio ◽

Guangyao Wang ◽

Ronald G. Goldy

Keyword(s):

Water Use Efficiency ◽

Chlorophyll Content ◽

Plant Height ◽

Water Use ◽

Irrigation Water ◽

Irrigation Water Use Efficiency ◽

Leaf Chlorophyll Content ◽

Leaf Chlorophyll ◽

Irrigation Water Use ◽

Use Efficiency

Field studies were conducted in 2003 and 2004 to determine effects of withholding irrigation on pepper (Capsicum annuum) plant height, leaf chlorophyll content, yield, and irrigation water use efficiency. Irrigation treatments were initiated at pepper transplanting (S0), after transplant establishment (S1), at first flower (S2), at first fruit (S3), or at fruit ripening (S4). The control treatment received only enough water to apply fertigation (FT). Withholding irrigation did not affect pepper plant height except FT treatment, but increased leaf chlorophyll content. Withholding irrigation until S4 saved 50% and 41% of irrigation water in 2003 and 2004, respectively, without affecting fruit yield compared with the treatment where irrigation started at transplanting. However, yield in the FT treatment was significantly reduced. Irrigation water use efficiency (pepper yield per unit area per millimeter of water applied) was maximum at S4 (59.1 kg·ha−1 per millimeter) and S3 (24.1 kg·ha−1 per millimeter) in 2003 and 2004, respectively. Similar trends in response of pepper to the irrigation treatments were observed in 2003 and 2004 even though there were large differences in rainfall, and pepper yield between years. This suggests that withholding irrigation until first fruit may help to maintain pepper yield while reducing irrigation costs. However, it is important to have adequate soil moisture at transplanting to insure adequate transplant establishment.

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Combining Ability and Gene Action Controlling Grain Yield and Its Related Traits in Bread Wheat under Heat Stress and Normal Conditions

Agronomy ◽

10.3390/agronomy11081450 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1450

Author(s):

Mohamed M. Kamara ◽

Khaled M. Ibrahim ◽

Elsayed Mansour ◽

Ahmed M. S. Kheir ◽

Mousa O. Germoush ◽

...

Keyword(s):

Heat Stress ◽

Grain Yield ◽

Chlorophyll Content ◽

Plant Height ◽

Bread Wheat ◽

Gene Action ◽

Stress Conditions ◽

Wheat Genotypes ◽

Sowing Dates ◽

Heat Tolerant

High temperature is a major environmental stress that devastatingly affects wheat production. Thenceforth, developing heat-tolerant and high-yielding wheat genotypes has become more critical to sustaining wheat production particularly under abrupt climate change and fast-growing global population. The present study aimed to evaluate parental genotypes and their cross combinations under normal and heat stress conditions, exploring their diversity based on dehydration-responsive element-binding 2 gene (DREB, stress tolerance gene in response to abiotic stress) in parental genotypes, and determining gene action controlling yield traits through half-diallel analysis. Six diverse bread wheat genotypes (local and exotic) and their 15 F1 hybrids were evaluated at two different locations under timely and late sowing dates. Sowing date, location, genotype, and their interactions significantly impacted the studied traits; days to heading, chlorophyll content, plant height, grain yield, and its attributes. Cluster analysis classified the parents and their crosses into four groups varying from heat-tolerant to heat-sensitive based on heat tolerance indices. The parental genotypes P2 and P4 were identified as an excellent source of beneficial alleles for earliness and high yielding under heat stress. This was corroborated by DNA sequence analysis of DREB transcription factors. They were the highest homologies for dehydrin gene sequence with heat-tolerant wheat species. The hybrid combinations of P1 × P5, P1 × P6, P2 × P4, and P3 × P5 were detected to be good specific combiners for grain yield and its attributes under heat stress conditions. These designated genotypes could be used in wheat breeding for developing heat-tolerant and climate-resilient cultivars. The non-additive genetic variances were preponderant over additive genetic variances for grain yield and most traits under both sowing dates. The narrow-sense heritability ranged from low to moderate for most traits. Strong positive associations were detected between grain yield and each of chlorophyll content, plant height, number of grains/spike, and thousand-grain weights, which suggest their importance for indirect selection under heat stress, especially in early generations, due to the effortlessness of their measurement.

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The applicability of empirical vegetation indices for determining leaf chlorophyll content over different leaf and canopy structures

Ecological Complexity ◽

10.1016/j.ecocom.2013.11.005 ◽

2014 ◽

Vol 17 ◽

pp. 119-130 ◽

Cited By ~ 68

Author(s):

H. Croft ◽

J.M. Chen ◽

Y. Zhang

Keyword(s):

Chlorophyll Content ◽

Vegetation Indices ◽

Leaf Chlorophyll Content ◽

Leaf Chlorophyll

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RIL-StEp: epistasis analysis of rice recombinant inbred lines (RILs) reveals candidate interacting genes that control seed hull color and leaf chlorophyll content

G3 Genes|Genome|Genetics ◽

10.1093/g3journal/jkab130 ◽

2021 ◽

Author(s):

Toshiyuki Sakai ◽

Akira Abe ◽

Motoki Shimizu ◽

Ryohei Terauchi

Keyword(s):

Chlorophyll Content ◽

Recombinant Inbred ◽

Complex Traits ◽

Genetic Architecture ◽

Recombinant Inbred Lines ◽

Inbred Lines ◽

Gene Interactions ◽

Leaf Chlorophyll Content ◽

Leaf Chlorophyll ◽

Seed Hull

Abstract Characterizing epistatic gene interactions is fundamental for understanding the genetic architecture of complex traits. However, due to the large number of potential gene combinations, detecting epistatic gene interactions is computationally demanding. A simple, easy-to-perform method for sensitive detection of epistasis is required. Due to their homozygous nature, use of recombinant inbred lines (RILs) excludes the dominance effect of alleles and interactions involving heterozygous genotypes, thereby allowing detection of epistasis in a simple and interpretable model. Here, we present an approach called RIL-StEp (recombinant inbred lines stepwise epistasis detection) to detect epistasis using single nucleotide polymorphisms in the genome. We applied the method to reveal epistasis affecting rice (Oryza sativa) seed hull color and leaf chlorophyll content and successfully identified pairs of genomic regions that presumably control these phenotypes. This method has the potential to improve our understanding of the genetic architecture of various traits of crops and other organisms.

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