Assessing different barley growth habits under Egyptian conditions for enhancing resilience to climate change

Abstract

Climate change poses challenges to agricultural production in general and to plant breeders in particular. Adaptation of cereals to the new conditions and increasingly variable situations arising from this process is essential to reduce risks and limit potential threats associated with climate hazards. This study presents the first attempt to assess the response and resilience of barley genotypes, with different growth habits across Egypt. For this purpose, eight field trials were conducted from 2013 to 2016 at three experimental sites with different winter climate configurations. The trials were sown at the end of November, following recommendations for the region. Fourteen barley genotypes were evaluated, comprising seven commercial Egyptian cultivars and seven European genotypes. The European genotypes were selected from successful cultivars from Spain, encompassing a range of growth types: two spring, three intermediate and two winter types. The cultivars were genotyped for six major adaptation genes, Vrn-H1-2-3, Ppd-H1-2 and HvCEN. One interesting finding is that, while the Egyptian cultivars were assumed to be of spring growth type, our results demonstrate that two cultivars, namely Giza123 and Giza126, are actually intermediate types (needing just a short period of vernalization). They contain the winter allele at Vrn-H2 together with Vrn-H1-4, the same as the European genotypes Cierzo and Orria, they also have an active allele at PpdH2, such as Hispanic. Overall, these four genotypes showed very good performance in all trials with low genotype-by-environment interaction. Moreover, a foreign late spring genotype (Pewter) was highly productive and a winter genotype (Hispanic) flowered as early as some intermediate and spring genotypes with a yield similar to genotypes currently grown in Egypt. A possible explanation for this surprising occurrence, the influence of an active allele at PpdH2 in winter cultivars, is discussed. In relation to low temperature, a high frequency of cold nights during wintertime was observed at all experimental sites, which seemed sufficient to promote timely flowering for intermediate genotypes, although this was inadequate for promoting flowering and achieving good productivity in strictly winter genotypes (e.g. Barberousse). Our findings also highlight the potential of exotic germplasm for breeding better and more resilient cultivars for autumn and for achieving good yield levels in regions with warm winters like Egypt. The results also provide insights into the usefulness of genetic variation in growth habit for breeders seeking adaptation to climate change conditions.

Grain yield stability of high-yielding barley genotypes under Egyptian conditions for enhancing resilience to climate change

“…Genotypes G16-G19 were chosen among several other non-Egyptian genotypes tested in these experiments for their good agronomic performance. The genotypes evaluated are spring types, except Giza 123 and Giza 126, which were assumed to be of springgrowth type but recently were demonstrated to be intermediate types (winter growth habit with a low vernalisation requirement) (Mansour et al 2018). These two genotypes are facultative from an agronomic point of view (they can be sown in winter or spring), but they are genetically different from facultative genotypes (as defined by Karsai et al 2005), having a true vernalisation need provided by an active VrnH2 gene and a reduced-vernalisation VrnH1 allele.…”

“…These two genotypes are facultative from an agronomic point of view (they can be sown in winter or spring), but they are genetically different from facultative genotypes (as defined by Karsai et al 2005), having a true vernalisation need provided by an active VrnH2 gene and a reduced-vernalisation VrnH1 allele. Nine of the genotypes evaluated (in addition to other five exotic genotypes) were evaluated in a companion study with focus on growth habit and adaptation (Mansour et al 2018). nitrogen, potassium and phosphate fertilisers, and for pest, disease and weed control, were followed as customary for barley in each region.…”

Multidimensional Evaluation for Detecting Salt Tolerance of Bread Wheat Genotypes Under Actual Saline Field Growing Conditions

“…However, evaluating the salt tolerance of field crops should be confirmed until the yielding stage and, most importantly, should be performed under real field conditions, especially when the evaluation of salt tolerance happens in the advanced generation of breeding programs [ 14 , 50 , 51 ]. This is because under real field conditions, the plants are exposed to natural and realistic conditions, such as spatial and temporal heterogeneity of soil, low humidity, drought stress, and high differences of diurnal temperature, all of which occur simultaneously with salinity stress [ 52 , 53 , 54 , 55 ]. This contributes to the recognition of appropriate genotypes that can be grown in salt-stress-affected regions and identification of genotypes as source and guide for improving and salt tolerance of bread wheat in breeding programs.…”

Availability and Feasibility of Water Desalination as a Non-Conventional Resource for Agricultural Irrigation in the MENA Region: A Review

“…Indeed, the amount of fresh water available to the citizens of MENA decreased by half from 3000 m 3 /capita to 1500 m 3 /capita from 1975 to 2001, largely due to rapid population growth. At present, a citizen in the MENA countries consumes slightly over 1000 m 3 , compared to the average global consumption, which reaches more than 7000 m 3 . In fact, most of the world's top twenty water-limited countries are in the MENA region [1].…”

“…Moreover, many countries in the MENA region are facing water scarcity, which impedes agricultural development. It is projected that the annual demand for water in the MENA region will increase almost five-fold from 42 to 200 km 3 by 2050 as a result of population growth and the expected negative effects of climate change. Indeed, the amount of fresh water available to the citizens of MENA decreased by half from 3000 m 3 /capita to 1500 m 3 /capita from 1975 to 2001, largely due to rapid population growth.…”