soil compaction in Agriculture

  'Terminal heat stress in barley'

Tassadduq Rasool

2007-ag-2092

Ph.D 2nd Semester

University of Agriculture, Faisalabad, Pakistan

[email protected]

+92-3023426583

Supervisor Name: Prof. Dr. Riaz Ahmad

Introduction

Barley is a rabbi cereal grain crop Ranked 4th in cereal Locally called ‘jao’(Urdu) Old English word “Beare” Latin word farina "flour"

Crop Botany

Family PoaceaeSelf pollinatedMonocot Diploid with 14 chromosome Inflorescence is spike Has short duration than wheat Source: http://en.wikipedia.org/wiki/Barley

Classification

• Hordeum distichum L.

• Two-rowed barley• Non shattering spikes

• Hordeum vulgare L.

• Six-rowed barley• Non shattering

spikes

Source: http://en.wikipedia.org/wiki/Barley

Source: http://en.wikipedia.org/wiki/Barley

Importance

• Holy Prophet Muhammad (PBUH) prescribed barley (talbina) for seven diseases. (Hadith. Volume 7, Book 71, Number 593: (Narrated 'Ursa))

• Animal feed• Health food• Bakery products • Beverages

Barley Production in Pakistan

Top Barley producing countries

A-biotic stresses

Abiotic stresses

Drought

Salinity

Freezing

Chilling

Heat

Definition

Heat stress is defined as the rise in temperature beyond a threshold level for a period of time sufficient to cause irreversible damage to plant growth and development (Wahid et al. 2007) .

Review

• Heat stress due to high ambient temperatures is a serious threat to

crop production worldwide (Hall, 2001).

• High temperature reduces duration of grain filling stages thereby

lowering the grain yield (Tiwari and Tripathy, 1999).

• Gawith (1999) reported optimal temperatures for grain filling as

residing between 19.3◦C and 22.1◦C.

• Despite impressive increases in wheat production after the Green Revolution, terminal heat caused by high temperatures during kernel development has emerged as a major threat to wheat production (Rane et al., 2007).

• The staple cereal crops can tolerate only narrow temperature ranges, which if exceeded during the flowering phase can damage fertilization and seed production, resulting in reduced yield (Porter, 2005).

• Furthermore, high temperatures during grain filling can modify flour and bread quality and other physico-chemical properties of grain crops (Wardlaw et al., 2002).

• Rising temperatures may lead to altered geographical distribution and growing season of agricultural crops by allowing the threshold temperature for the start of the season and crop maturity to reach earlier (Porter, 2005).

Reason

• Plants may be damaged by high day or high night temperatures and

by either high air or high soil temperatures.

• Global warming

• Global mean temperature will rise 0.3 0C per decade

(Intergovernmental panel on climate change, IPCC)

Morphological Symptoms of Heat stress

• Necrosis on leaves• Scorchy appearance of leaves• Reduction in leaf size• White spots due to chlorophyll destruction• Leakage of sap make more prone to pathogen attack• Sunburn on leaves, stems and branches• Fruits discoloration and damage• Wilting

Phenological changes

Reproductive stages

Flowers abortion

Impairment of pollen and anther development

Earlier heading

Temperature can modify flour and bread quality

Physiological changes

• Photosynthesis• Leaf senescence• Water relations• Grain growth and development• Grain quality

Mechanism of Injury

• Protien denaturation• Respiration (Doubles for every 10 0C)• Photosynthesis (In C3 plants affected above 350C)• Production of ROS• Heat induced Drought• Starvation (More respiration than Photosynthesis) (Wahid et al., 2007)

How Photosynthesis affected

Farooq et al., 2011:Critical Reviews in Plant Sciences, 30:491–507, 2011

Definition

• Heat tolerance is generally defined as the ability of the plant to grow and produce economic yield under high temperatures.

Mechanism of Heat tolerance

• Transpiration as a coolant• Structural adaptation• Molecular basis• Antioxidant

Agronomic management strategies

• Practices that conserve water • Fertilization during critical growth stages and

timing of sowing• Time of sowing: Early planting may avoid terminal

heat stress

References

• Wahid. T., S. Gelani, M. Ashraf, M.R. Foolad. 2007. Heat tolerance in plants: An overview. Environ. Exp. Bot. 61: 199-223.

• Hall, A.E., 2001. Crop Responses to Environment. CRC Press LLC, Boca Raton, Florida.

• Tewari, A.K. and B.C. Tripathy, 1999. Acclimation of chlorophyll biosynthetic reactions to temperature stress in cucumber (Cucumis sativus L.). Planta, 208: 431–437.

• http://www.fao.org/inpho/inpho-post-harvest-compendium/cereals-grains/en/.• Streck, N.A., 2005. Climate change and agroecosystems: the effect of elevated

atmospheric CO2 and temperature on crop growth, development and yield. Ciência Rural, 35: 730–740.

• Asthir, B. R. Thapar, M.Farooq and N.S. Bains. 2013.Exogenous application of thiourea improves the performance of late ssown wheat by inducing terminal heat stress. Int. J. Agric. Biol. 15: 1337-1342.

References

• Porter, J.R., M. Gawith. 1999. Temperatures and the growth and development of wheat: a review. European Journal of Agronomy 10: 23–36.

• Gate, P., Brisson, N., 2010. Advancement of phenological stages and shortening of phases. In: Brisson, N., Levrault, F. (Eds.), Climate change, agriculture and forests in France: simulations of the impacts on the main species. The Green Book of the CLIMATOR project (2007–2010). ADEME, Angers, France, 65–78.

• Rane, J., Pannu, R.K., Sohu, V.S., Saini, R.S., Mishra, B., Shoran, J., Crossa, J., Vargas, M., Joshi, A.K., 2007. Performance of yield and stability of advanced wheat geno-types under heat stressed environments of Indo-Gangetic plains. Crop Sci. 47,1561–1573.

• Joshi, M. 2007. Performance of yield and stability of advanced wheat geno-types under heat stressed environments of Indo-Gangetic plains. Crop Sci. 47, 1561–1573.

• Porter, J.R., 2005. Rising temperatures are likely to reduce crop yields. Nature . 436: 174.•  Hadith. Volume 7, Book 71, Number 593: (Narrated 'Ursa)

References

• Kobata, T., Palta, J. A., and Turner, N. C. 1992. Rate of development of post anthesis water deficits and grain filling of spring wheat. Crop Sci. 32: 1238–1242.

• Streck, N. A. 2005. Climate change and agroecosystems: the effect of elevated atmospheric CO2 and temperature on crop growth, development and yield. Ciencia Rural35: 730–740.

• Yang, J., Sears, R. G., Gill, B. S., and Paulsen, G. M. 2002. Geno-ypic differences in utilization of assimilate sources during maturation of wheat under chronic heat and heat shock stresses.Euphytica125: 179–188.

• Zhao, H., Dai, T. B., Jing, Q., Jiang, D., and Cao, W. X. 2007. Leaf senescence and grain filling affected by post-anthesis high temperatures in two different wheat cultivars. Plant Growth Regul.51:149–158.

Barley Aurical without hair

Wilde Oat without AuricalWheat Aurical With hair

Temperature Thresholds

Lethal limits• -17.2 (1.2)• +47.5 (0.5)