Sources of Cold Tolerance in Grain Sorghum

Abstract

Srr'rcn, S. P. 1985. Sources

Field Technique and Traits to Assess Reproductive Stage Cold Tolerance in Sorghum (Sorghum bicolor (L.) Moench

“…The genotypic cold tolerance during the vegetative stage is independent of cold tolerance during the reproductive stage and cold tolerance appeared to be a dominant trait. However, several genes control the inheritance of the character and their effects are largely cumulative (Singh, 1985). Therefore, it is important to develop a highly reproducible protocol for assessing reproductive stage cold tolerance, within the same field trials that are intended for grain yield selection.…”

“…Generally, sorghum is a warm-season crop mainly grown in semiarid, sub-humid, and humid tropical and subtropical parts of the world where average minimum temperatures generally stay above 18ºC during the growing season (Singh, 1985). However, a substantial amount of sorghum has been grown for centuries in the cooler highland areas of Burundi, Ethiopia, Rwanda, Uganda, and the Yemen Arab Republic in Africa.…”

“…Most available screening techniques and studies on cold tolerance are not suitable for adoption across the growing environments and most of them deal with seedling response to cold (Yu et al, 2004). Most of the genotypes that are tolerant at the vegetative stage do not show tolerance to cold during the reproductive stage (Singh, 1985). Therefore, developing a field screening technique to assess reproductive stage cold tolerance and to identify sources of tolerance is very crucial for enhancing the yield potential and stability, particularly in post-rainy season.…”

“…However, a substantial amount of sorghum has been grown for centuries in the cooler highland areas of Burundi, Ethiopia, Rwanda, Uganda, and the Yemen Arab Republic in Africa. These sorghums are adapted to cold growing periods that should have merit in other parts of the world, especially the highlands of Latin America (Bolivia, Colombia, Ecuador, El Salvador, Guatemala, Honduras, Mexico and Peru), northern and northwestern USA, and southern Canada where rainfall is scarce and erratic, and where soils and growing conditions are generally less suitable for other major food and feed crops (Singh, 1985;Yu et al, 2004). In South Asia, particularly in India, major high quality sorghum production comes from post-rainy season crop grown under receding soil moisture after the cessation of the rains with their peak flowering coinciding with the cooler days in winter.…”

Proline as a probable biomarker of cold stress tolerance in Sorghum (Sorghum bicolor)

“…These sorghums are cold tolerant and can grow on the high ground less suitable for sorghum cultivation. The term "cold tolerance" is used to describe the ability of sorghum genotypes to germinate, grow and produce seed satisfactorily under conditions of low temperatures, but above freezing (Singh, 1985). When susceptible sorghums are cultivated in cold conditions one or more of the following features happens: reduced, or no germination (Tiryaki & Andrews, 2001), the predisposition of sorghum to diseases (McLaren & Wehner, 1992), and female or male sterility which leads to decreased seed production (Downes & Marshall, 1971).…”