Neelam ARA, Zhongyuan HU, Mingfang ZHANG, Jinghu YANG

Determination of heat tolerance of interspecific (Cucurbita maxima x cucurbita moschata) inbred line of squash ‘Maxchata’ and its parents through photosynthetic response

Artan nüfus için gıda temini ve küresel ısınmanın oluşturduğu zorluklarla mücadele için sıcaklık stresine toleranslı çeşit geliştirmek gerekmektedir. Bu çalışma, Maxchata’ olarak bilinen ve yeni geliştirilmiş kendilenmiş türler arası melez kabak hattının fotosentetik karakteristikleri yoluyla sıcaklık stresine karşı tolerans seviyesinin belirlenmesi ve ebeveynlerinin (C. maxima ve C. moschata) performansı ile karşılaştırılması amacıyla yapılmıştır. Bu üç genotipe ait bitkiler 7 gün süre ile 30/25 °C gündüz/gece (kontrol), 37/32 °C gündüz/gece (orta sıcaklık stresi) ve 42/37 °C gündüz/gece (şiddetli sıcaklık stresi) sıcaklık derecesine maruz bırakılmıştır. Sonuçlar, sıcaklık artışına bağlı olarak net fotosentez oranı (PN), stoma iletkenliği (gs), terleme oranı (E) ve PSII (Fv/Fm)’nin maksimum fitokimyasal etkinliği gibi bazı gaz değişim karakteristiklerinin önemli derecede düştüğünü, bununla birlikte hücrelerarası karbondioksit (Ci) konsantrasyonun arttığını (stomadan kaynaklanmayan sınırlamaları) göstermiştir. Bunun ötesinde, yüksek sıcaklık şokuna bağlı olarak birlikte klorofil pigmentleri parçalanmış ve sonuçta Chl a/b oranı yükselmiş ve klorofil/karotenoid oranı azalmıştır. Ancak, bu değişim C. maxima’ da daha belirgin olmuş, bunu Maxchata’ takip etmiş ve ardından C. moschata gelmiştir. C. moschata sıcaklık rejimlerine karşı en iyi fotosentetik mekanizmaya sahip bulunmuş, bunu ‘Maxchata’ izlemiş, ancak en hassas C. maxima olmuştur. Belli derecede sıcaklık toleransına sahip olan melez ‘Maxchata’nın iklim değişikliği etkisine karşı yararlı olabileceği düşünülmektedir.

Kendilenmiş Türler Arası Melez Kabak Hattı ‘Maxchata’ (Cucurbita maxima x Cucurbita moschata)’nın ve ebeveynlerinin fotosentetik tepki yoluyla sıcaklık toleransının belirlenmesi

Development of heat tolerant cultivars is needed to combat the challenges of global warming and food supply to increasing population. This study was conducted to determine the extent of heat tolerance of newly developed interspecific inbred line of squash named as ‘Maxchata’ through its photosynthetic attributes compared to its parents C. maxima and C. moschata. Plants of these three genotypes were subjected to three different temperatures i.e 30 °C day/25 °C night as control, 37 °C day/32 °C night as moderate heat stress and 42 °C day/37 °C night as severe heat stress, for seven days. Results showed that various gas exchange attributes such as net photosynthesis rate (PN), stomatal conductance (gs) and transpiration rate (E) as well as maximum photochemical efficiency of PSII (Fv/Fm) dropped significantly with increasing temperature, while intercellular CO2 concentration (Ci) increased showing the nonstomatal limitations. Further, chlorophyll pigments also degraded with heat shocks resulting in higher Chl a to b ratio and decreased chlorophyll to carotenoids ratio. However, these trends were more abrupt in C. maxima, chased by ‘Maxchata’ and then C. moschata. C. moschata had the best photosynthetic machinery to sustain the heat regimes, followed by ‘Maxchata’, while C. maxima was the most susceptible. Hybrid ‘Maxchata’ with some degree of heat tolerance might have ability to cope with the climate change.

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Balkaya A Özbakir M & Karaağaç O (2010). Evaluation of variation and fruit characterization of pumpkin (Cucurbita moschata Duch.) populations collected from Black Sea Region. Tarım Bilimleri Dergisi – Journal of Agricultural Sciences 16: 17-25
Berry J & Bjorkman O (1980). Photosynthetic response and adaptation to temperatures in higher plants. Annual Review of Plant Physiology 31: 491-543
Bisognin D A (2002). Origin and evolution of cultivated cucurbits. Ciência Rural, Santa Maria 32(5): 715-723
Camejo D & Torres W (2001). High temperature effect of tomato (Lycopersicon esculentum) pigment and protein content and cellular viability. Cultivos Tropicales 22(3): 13-17
Camejo D, Rodriguez P, Morales M A, Dellamico J M, Torrecillas A & Alarcon J J (2005). High temperature effects on photosynthetic activity of two tomato cultivars with different heat susceptibility. Journal of Plant Physiology 162: 281–289
Crafts-Brandner S J & Salvucci M E (2000). Rubisco activase constrains the photosynthetic potential of leaves at high temperature and CO2. Proceedings of the National Academy of Sciences 97: 13430–13435
Crafts-Brandner S J & Salvucci M E (2002). Sensitivity to photosynthesis in the C4 plant maize to heat stress. Plant Cell 12: 54–68
De Ronde J A D, Cress W A, Kruger G H J, Strasser R J & Staden J V (2004). Photosynthetic response of transgenic soybean plants containing an Arabidopsis P5CR gene, during heat and drought stress. Journal of Plant Physiology 61: 1211–1244
Dinar M & Rudich J (1985). Effect of heat stress on assimilate partitioning in tomato. Annals of Botany 56: 239-248
Djanaguiraman M, Prasad P V V, Boyle D L & Schapaugh W T (2011). High temperature stress and soybean leaves: Leaf anatomy and Photosynthesis. Crop Science 51: 2025-2031
FAO (2011). Food and agriculture organization of the United Nations. Classifications and standards. Website: http://faostat.fao.org/site/339/default.aspx
Guo F L, Yu J, Tao J, Su J & Zhang C H (2009). Effects of high temperature stress on photosynthesis and chlorophyll fluorescence of Euphorbia pulcherrima. Journal of Yangzhou University Agricultural and Life Science 30(3): 71-74
Guo Y P, Zhou H F & Zhang L C (2006). Photosynthetic characteristics and protective mechanisms against photo-oxidation during high temperature stress in two citrus species. Scientia Horticulturae 108: 260–267
Hall A E (1992). Breeding for heat tolerance. Plant Breeding Reviews 10: 129–168
Hammes P S & Jager J A (1990). Net photosynthetic rate of potato at high temperatures. Potato Research 33(4): 515-520
Hassan I A (2006). Effect of water stress and high temperature on gas exchange and chlorophyll fluorescence in Triticum aestivum. Photosynthetica 44(2): 312-315
IPCC (2007). Intergovernmental Panel on Climate Change fourth assessment report. Climate change. Cambridge University Press, Cambridge, UK.
Jensen R G (2000). Activation of Rubisco regulates photosynthesis at high temperature and CO2. Proceedings of the National Academy of Sciences 97(24): 12937-12938
Jones P D, New M, Parker D E, Mortin S & Rigor I G (1999). Surface area temperature and its change over the past 150 years. Reviews of Geophysics 37: 173– 199
Lin Y, Medlyn B E & Ellsworth D S (2012). Temperature response of leaf net photosynthesis: the role of component processes. Tree Physiology 32(2): 219- 231
Malik M N (1996). Vegetable Crops In Horticulture. National book foundation Islamabad, Pakistan. 2nd Edition. pp: 504-505
Maxwell K & Johnson G N (2000). Chlorophyll fluorescence- a practical guide. Journal of Experimental Botany 51: 659-668
Morales D, Rodriguez P, Dellamico J, Nicolas E, Torrecillas A & Sanchez-Blanco M J (2003). High- temperature preconditioning and thermal shock imposition affects water relations, gas exchange and root hydraulic conductivity in tomato. Biologia Plantarum 47: 203–208
Ogweno J O, Zhou Y H & Yu J Q (2009). Changes in activities of antioxidant enzymes and photosynthesis in detached leaves of tomato after exposure to different temperatures. African Journal of Horticultural Science 2: 124-137
Paris H S (1994). Genetic analysis and breeding of pumpkins and squash for high carotene contents. Modern methods of plant analysis. Vegetable and Vegetable Products 16: 93-105
Pastene C & Horton P (1996). Effect of high temperature on photosynthesis in Beans. Plant Physiology 112: 1253-1260
Pires M V, Almeida A F, Figueiredo A L, Gomes F P & Souza M M (2011). Photosynthetic characteristics of ornamental passion flowers grown under different light intensities. Photosynthetica 49(4): 593-602
Porra R J, Thompson W A & Kriedemann P E (1989). Determination of accurate extinction coefficients and simultaneous equations for assaying chlorophylls a and b extracted with four different solvents: verification of the concentration of chlorophyll standards by atomic absorption spectroscopy. Biochimica Et Biophysica Acta-Bioenergetics 975: 384-394
Reed S, Schnell R, Moore J M & Dunn C (2012). Chlorophyll a + b contents and chlorophyll fluorescence in Avocado. Journal of Agricultural Sciences 4(4): 29-36
Rohacek K (2002). Chlorophyll fluorescence parameters: The definitions, photosynthetic meaning, and mutual relationships. Photosynthetica 40: 13-29
SAS Institute (2003). SAS users guide. Version 9.1. SAS Institute. Cary, NC
Sinsawat V, Leipner J, Stamp & Fracheboud Y (2004). Effect of heat stress on the photosynthetic apparatus in maize (Zea mays L.) grown at control or high temperature. Environmental and Experimental Botany 52: 123–129
Wahid A, Gelani S, Asraf M & Foolad M R (2007). Heat tolerance in plants an overview. Environmental and Experimental Botany 61: 199–223
Whiteman P C & Koller D (1967). Interactions of carbon dioxide concentration, light intensity and temperature on plant resistances to water vapour and carbon dioxide diffusion. New Phytologist 66: 463-473
Wise R R, Olson A J, Schrader S M & Sharkey T D (2004). Electron transport is the functional limitation of photosynthesis in field-grown Pima cotton plants at high temperature. Plant Cell and Environment 27: 717–724
Wolf S, Olesinski A A, Rudich J & Marani A (1990). Effect of High Temperature on Photosynthesis in Potatoes. Annals of Botany 65: 179-185
Zeng B, Xu X, Zhou S, Zhu C & Tang C (2012). Effects of Temperature and Light on Photosynthetic heterosis of an upland cotton hybrid cultivar. Crop Science 52: 282-291
Zhang S, Ma K & Chen L (2003). Response of photosynthetic plasticity of Paeonia suffruticosa to changed light environments. Environmental and Experimental Botany 49: 121-133