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Drought stress is the primary abiotic factor affecting wheat growth, development, and yield formation. The application of plant growth-promoting rhizobacteria (PGPR) represents an environmentally sustainable approach to mitigate the impacts of drought stress on wheat. This study conducted field experiments using two winter wheat varieties, the drought-sensitive variety Jimai 22 and the drought-resistant variety Chang 6878, aiming to investigate the effects of Streptomyces pactum Act12 inoculation on photosynthetic characteristics, physiological parameters, and yield traits during the jointing, heading, and middle-filling stages under drought stress. The results revealed that drought stresses significantly reduced chlorophyll content, leaf area, biomass, and yield in wheat, while Act12 inoculation significantly increased chlorophyll content, photosynthetic efficiency, antioxidant enzyme activity such as superoxide dismutase (SOD) and peroxidase (POD), osmolyte content (proline and soluble proteins), and decreased malondialdehyde (MDA) content. These combined effects alleviated drought stress, resulting in increased biomass and yield in wheat. Under drought stress, an increase in leaf proline content of 13.53% to 53.23% (Jimai 22) and 17.17% to 43.08% (Chang 6878) was observed upon Act12 inoculation. Moreover, a decrease in MDA content was recorded of 15.86% to 53.61% (Jimai 22) and 13.47% to 26.21% (Chang 6878). Notably, there was a corresponding increase in yield of 11.78% (Jimai 22) and 13.55% (Chang 6878). In addition, grain quality analysis revealed a significant improvement in grain hardness with Act12 inoculation. Therefore, Act12 demonstrates the potential for enhancing the sustainable development of wheat production in arid and semi-arid regions. [ABSTRACT FROM AUTHOR]

Despite its ability to thrive in high-temperature environments, cowpea productivity can be hampered by heat stress, particularly when night air temperatures exceed 17 °C. The crop's germplasm pool potentially possesses significant genetic variability that can be harnessed to breed for heat-tolerant varieties. Progress in improving the crop for heat tolerance has been limited, especially under the hot, short-day environments typical of sub-Saharan Africa. Only a few heat-tolerant varieties have been released, partly due to the limited understanding of heat stress tolerance mechanisms and environmental interaction effects on genotypes, as well as imprecise phenotyping. This review contributes to the literature on cowpea heat stress by highlighting key achievements, challenges, and future directions in breeding heat-tolerant cowpea genotypes and by providing additional information from the recent literature. We opine that the genetic variability for heat tolerance-related traits in cowpea has not been sufficiently exploited in developing varieties adapted to the target production environments. Therefore, attention should be given to assessing the crop's genetic repository by targeting adaptive, morphological, and physiological traits that enhance heat stress tolerance. We propose that breeding programs integrate phenotyping of whole-plant physiological traits and molecular breeding to identify breeder-friendly markers for routine selection. This should be followed by introgression of the heat-tolerant favourable alleles to adapted susceptible varieties using rapid and precise approaches that take advantage of modern genetic and genomic resources such as innovative genetic resources, genomic selection, speed breeding, and genome editing technologies. These tools hold great promise in fast-tracking the development of improved heat-tolerant varieties and incorporating the must-have traits preferred by cowpea farmers and consumers. In view of the likely increase in atmospheric temperature to be occasioned by climate change, there is an urgent need to develop heat-tolerant cowpea varieties to ensure the sustainability of current and future cropping and agri-food systems. [ABSTRACT FROM AUTHOR]

The leading role of Italy in the cultivation of durum wheat stimulated intense breeding activities in the country from the beginning of the 20th century, much earlier than in any other country involved in durum wheat production. Older, genetically more heterogeneous landraces were replaced with new, highly productive, superior quality varieties, and this led to an inevitable reduction in the overall genetic diversity among new cultivars, which makes the genetic variability preserved in old cultivars particularly valuable and important. The aim of this paper was to assist future breeding programs by providing a detailed description of the history of durum wheat breeding in Italy and of the changes in yield, quality, and related traits that subsequently occurred, starting from the most diffuse landraces present between 1900 and 1920 up until the present day. The parallel evolution of breeding techniques, breeding goals, and agricultural systems in this period is also described, and some future breeding goals suggested. In the current context of climate change and of rapidly mutating pathogen populations, preserving the yield level through the continuous introduction of new cultivars by exploiting the reservoir of largely unused genetic variation stored in old cultivars and landraces could be as important as increasing grain yield and quality. [ABSTRACT FROM AUTHOR]

Drought stress poses a considerable challenge to agriculture sustainability in arid regions. Water scarcity severely affects date palm growth and productivity in these regions. However, as water resources become increasingly scarce in arid regions, understanding the drought tolerance of date palm cultivars becomes imperative for developing drought-resistant cultivars and optimizing irrigation water usage for sustainable agriculture. This research examines the impact of different drought stress levels based on evapotranspiration (ETc), i.e., 40%, 60%, 80%, and 100% ETc, and time intervals (0, 6, 12, 18, and 24 months) on leaf growth, net photosynthesis, chlorophyll a and b content, and leaf relative water content (LRWC) of four prominent date palm cultivars, Khalas, Barhee, Hilali, and Ashrasee. In addition, the study also examines the effects of drought stress on dry weight, potassium and calcium content of leaf, stem, and root, and proline content in fresh leaves of these four cultivars. A solar-powered drip irrigation system with automated time-based irrigation scheduling was used to accurately control the irrigation water amount. To real-time estimate ETc in the study area, meteorological data were collected using a cloud-based IoT system. The findings of this study revealed that severe drought conditions (40 and 60 % ETc) significantly reduced leaf growth, plant dry biomass, and physiological and biochemical attributes; however, date palm cultivars can be grown under moderate drought conditions (80% ETc) with minimal effect on phenotypic, physiological, and biochemical traits to conserve water. The study also revealed that the drought-related characteristics decreased gradually with an increase in water stress time over 24 months. Comparing the date palm cultivars revealed that the Khalas and Barhee cultivars are more drought-tolerant, followed by Hilali, while Ashrasee is susceptible. The study elucidated a water conservation strategy employed in response to drought-induced stress based on the physiological and morphological parameters of date palm cultivars. It provides valuable insights into irrigation practices in arid regions. However, future studies can be focused on other nondestructive innovative techniques such as pulse-amplitude-modulation (PAM) fluorimetry, infrared radiation (IR), and video imaging system (VIS) methods to identify drought stress in date palms. [ABSTRACT FROM AUTHOR]

Sorghum holds the potential for enhancing food security, yet the impact of the interplay of water stress and salinity on its growth and productivity remains unclear. To address this, we studied how drought and salinity affect physiological traits, water use, biomass, and yield in different tropical sorghum varieties, utilizing a functional phenotyping platform, Plantarray. Cultivars (Kuali, Numbu, Samurai2) were grown under moderate and high salinity, with drought exposure at booting stage. Results showed that Samurai2 had the most significant transpiration reduction under moderate and high salt (36% and 48%) versus Kuali (22% and 42%) and Numbu (19% and 16%). Numbu reduced canopy conductance (25% and 15%) the most compared to Samurai2 (22% and 33%) and Kuali (8% and 35%). In the drought*salinity treatment, transpiration reduction was substantial for Kuali (54% and 57%), Samurai2 (45% and 60%), and Numbu (29% and 26%). Kuali reduced canopy conductance (36% and 53%) more than Numbu (36% and 25%) and Samurai2 (33% and 49%). Biomass, grain yield, and a-100 grain weight declined in all cultivars under both salinity and drought*salinity, and Samurai2 was most significantly affected. WUEbiomass significantly increased under drought*salinity. Samurai2 showed reduced WUEgrain under drought*salinity, unlike Kuali and Numbu, suggesting complex interactions between water limitation and salinity in tropical sorghum. [ABSTRACT FROM AUTHOR]

Drought stress is the primary abiotic factor affecting wheat growth, development, and yield formation. The application of plant growth-promoting rhizobacteria (PGPR) represents an environmentally sustainable approach to mitigate the impacts of drought stress on wheat. This study conducted field experiments using two winter wheat varieties, the drought-sensitive variety Jimai 22 and the drought-resistant variety Chang 6878, aiming to investigate the effects of Streptomyces pactum Act12 inoculation on photosynthetic characteristics, physiological parameters, and yield traits during the jointing, heading, and middle-filling stages under drought stress. The results revealed that drought stresses significantly reduced chlorophyll content, leaf area, biomass, and yield in wheat, while Act12 inoculation significantly increased chlorophyll content, photosynthetic efficiency, antioxidant enzyme activity such as superoxide dismutase (SOD) and peroxidase (POD), osmolyte content (proline and soluble proteins), and decreased malondialdehyde (MDA) content. These combined effects alleviated drought stress, resulting in increased biomass and yield in wheat. Under drought stress, an increase in leaf proline content of 13.53% to 53.23% (Jimai 22) and 17.17% to 43.08% (Chang 6878) was observed upon Act12 inoculation. Moreover, a decrease in MDA content was recorded of 15.86% to 53.61% (Jimai 22) and 13.47% to 26.21% (Chang 6878). Notably, there was a corresponding increase in yield of 11.78% (Jimai 22) and 13.55% (Chang 6878). In addition, grain quality analysis revealed a significant improvement in grain hardness with Act12 inoculation. Therefore, Act12 demonstrates the potential for enhancing the sustainable development of wheat production in arid and semi-arid regions.

Despite its ability to thrive in high-temperature environments, cowpea productivity can be hampered by heat stress, particularly when night air temperatures exceed 17 °C. The crop’s germplasm pool potentially possesses significant genetic variability that can be harnessed to breed for heat-tolerant varieties. Progress in improving the crop for heat tolerance has been limited, especially under the hot, short-day environments typical of sub-Saharan Africa. Only a few heat-tolerant varieties have been released, partly due to the limited understanding of heat stress tolerance mechanisms and environmental interaction effects on genotypes, as well as imprecise phenotyping. This review contributes to the literature on cowpea heat stress by highlighting key achievements, challenges, and future directions in breeding heat-tolerant cowpea genotypes and by providing additional information from the recent literature. We opine that the genetic variability for heat tolerance-related traits in cowpea has not been sufficiently exploited in developing varieties adapted to the target production environments. Therefore, attention should be given to assessing the crop’s genetic repository by targeting adaptive, morphological, and physiological traits that enhance heat stress tolerance. We propose that breeding programs integrate phenotyping of whole-plant physiological traits and molecular breeding to identify breeder-friendly markers for routine selection. This should be followed by introgression of the heat-tolerant favourable alleles to adapted susceptible varieties using rapid and precise approaches that take advantage of modern genetic and genomic resources such as innovative genetic resources, genomic selection, speed breeding, and genome editing technologies. These tools hold great promise in fast-tracking the development of improved heat-tolerant varieties and incorporating the must-have traits preferred by cowpea farmers and consumers. In view of the likely increase in atmospheric temperature to be occasioned by climate change, there is an urgent need to develop heat-tolerant cowpea varieties to ensure the sustainability of current and future cropping and agri-food systems.

The leading role of Italy in the cultivation of durum wheat stimulated intense breeding activities in the country from the beginning of the 20th century, much earlier than in any other country involved in durum wheat production. Older, genetically more heterogeneous landraces were replaced with new, highly productive, superior quality varieties, and this led to an inevitable reduction in the overall genetic diversity among new cultivars, which makes the genetic variability preserved in old cultivars particularly valuable and important. The aim of this paper was to assist future breeding programs by providing a detailed description of the history of durum wheat breeding in Italy and of the changes in yield, quality, and related traits that subsequently occurred, starting from the most diffuse landraces present between 1900 and 1920 up until the present day. The parallel evolution of breeding techniques, breeding goals, and agricultural systems in this period is also described, and some future breeding goals suggested. In the current context of climate change and of rapidly mutating pathogen populations, preserving the yield level through the continuous introduction of new cultivars by exploiting the reservoir of largely unused genetic variation stored in old cultivars and landraces could be as important as increasing grain yield and quality.

Intensive greenhouse vegetable production is often associated with a decline of crop productivity due to the increase of soil salinity and/or a reduction of biological fertility. The aim of the current work was to assess the effects of three organic fertilizers on morpho-physiological and agronomic traits of greenhouse lettuce as well as soil enzyme activity under poor soil quality conditions. The tested organic fertilizers (poultry manure, vinasse-based fertilizer, and insect's frass fertilizer) were applied pre-planting at the same equivalent nitrogen (N) rate (90 kg N ha−1). Laboratory incubation assay results showed that vinasse-based fertilizer was the most suitable fertilizer in supplying the mineral N in the short term. All fertilizers increased shoot fresh and dry weight compared to unfertilized control with a more pronounced effect (+75%) with vinasse-based fertilizer and insect's frass. Insect frass reduced by 27% the leaf nitrate concentration in comparison with the other treatments. The toxic heavy metal Pb was 46% lower in all organically fertilized lettuce leaves. Soil enzymatic activities of acid phosphatase, alkaline phosphatase, arylsulfatase (ArS), N-acetyl-β-D-glucosaminidase (NAGase), dehydrogenase, and total hydrolase (THA) were enhanced by poultry manure and insect's frass in comparison with unfertilized control while vinasse-based fertilizer increased ArS, NAGase, and THA. Taken together, our data demonstrate that the application of organic fertilizers especially vinasse-based fertilizer and insect's frass during intensive crop production is a suitable approach for mitigating the negative impact of soil salinity, enhancing soil biological fertility, and improving agronomic performance of greenhouse lettuce. [ABSTRACT FROM AUTHOR]

Canker symptoms were observed on almond trees in the Fez-Meknes region, Morocco. Isolations were conducted from the infected branch and trunk showing internal and external brown lesions. Four representative fungal isolates were screened, and their identities were confirmed by cultural traits and sequence analysis of DNA using two genes, the ITS region (internal transcribed spacer) and calmodulin (cmdA). The identified fungi were Curvularia hawaiiensis, Fusarium ambrosium, Lasiodiplodia theobromae, and Chondrestereum purpureum. The pathogenicity test on almond twigs revealed that these species were pathogenic to their host with different degrees of virulence, with Lasiodiplodia theobromae as the most virulent causing the longest necrotic lesion (285.17 mm) and the death of twigs. Physiological traits analysis of the above-mentioned fungi showed that the optimum mycelium growth response at different temperatures varies from 10 to 35 °C, while the pH ranges between 3.0 and 8.0. This study confirms the presence of canker pathogens on almond trees, which will contribute valuable information to improve the understanding of the contemporary status of almond trees, thus helping the improvement of the management of almond orchards. To our knowledge, all these fungi represent new records in Morocco and some of them are confirmed on the almond trees for the first time in the world. [ABSTRACT FROM AUTHOR]

Sorghum holds the potential for enhancing food security, yet the impact of the interplay of water stress and salinity on its growth and productivity remains unclear. To address this, we studied how drought and salinity affect physiological traits, water use, biomass, and yield in different tropical sorghum varieties, utilizing a functional phenotyping platform, Plantarray. Cultivars (Kuali, Numbu, Samurai2) were grown under moderate and high salinity, with drought exposure at booting stage. Results showed that Samurai2 had the most significant transpiration reduction under moderate and high salt (36% and 48%) versus Kuali (22% and 42%) and Numbu (19% and 16%). Numbu reduced canopy conductance (25% and 15%) the most compared to Samurai2 (22% and 33%) and Kuali (8% and 35%). In the drought*salinity treatment, transpiration reduction was substantial for Kuali (54% and 57%), Samurai2 (45% and 60%), and Numbu (29% and 26%). Kuali reduced canopy conductance (36% and 53%) more than Numbu (36% and 25%) and Samurai2 (33% and 49%). Biomass, grain yield, and a-100 grain weight declined in all cultivars under both salinity and drought*salinity, and Samurai2 was most significantly affected. WUEbiomass significantly increased under drought*salinity. Samurai2 showed reduced WUEgrain under drought*salinity, unlike Kuali and Numbu, suggesting complex interactions between water limitation and salinity in tropical sorghum.

Drought stress poses a considerable challenge to agriculture sustainability in arid regions. Water scarcity severely affects date palm growth and productivity in these regions. However, as water resources become increasingly scarce in arid regions, understanding the drought tolerance of date palm cultivars becomes imperative for developing drought-resistant cultivars and optimizing irrigation water usage for sustainable agriculture. This research examines the impact of different drought stress levels based on evapotranspiration (ETc), i.e., 40%, 60%, 80%, and 100% ETc, and time intervals (0, 6, 12, 18, and 24 months) on leaf growth, net photosynthesis, chlorophyll a and b content, and leaf relative water content (LRWC) of four prominent date palm cultivars, Khalas, Barhee, Hilali, and Ashrasee. In addition, the study also examines the effects of drought stress on dry weight, potassium and calcium content of leaf, stem, and root, and proline content in fresh leaves of these four cultivars. A solar-powered drip irrigation system with automated time-based irrigation scheduling was used to accurately control the irrigation water amount. To real-time estimate ETc in the study area, meteorological data were collected using a cloud-based IoT system. The findings of this study revealed that severe drought conditions (40 and 60 % ETc) significantly reduced leaf growth, plant dry biomass, and physiological and biochemical attributes; however, date palm cultivars can be grown under moderate drought conditions (80% ETc) with minimal effect on phenotypic, physiological, and biochemical traits to conserve water. The study also revealed that the drought-related characteristics decreased gradually with an increase in water stress time over 24 months. Comparing the date palm cultivars revealed that the Khalas and Barhee cultivars are more drought-tolerant, followed by Hilali, while Ashrasee is susceptible. The study elucidated a water conservation strategy employed in response to drought-induced stress based on the physiological and morphological parameters of date palm cultivars. It provides valuable insights into irrigation practices in arid regions. However, future studies can be focused on other nondestructive innovative techniques such as pulse-amplitude-modulation (PAM) fluorimetry, infrared radiation (IR), and video imaging system (VIS) methods to identify drought stress in date palms.

The capture and utilization of rainwater by crops under various mulching conditions have great importance in agriculture production systems, especially in dry-prone regions. Understanding the effect of mulching on rainwater use efficiency growth and yield of a crop is very important. For this purpose, field experiments were conducted in 2017 and 2018 to evaluate the potential of ridge-furrow mulching on maize growth and development under rain-fed conditions. The field study compared four treatments, i.e., ridge-furrow without mulch (WM), black plastic mulch (BM), transparent plastic mulch (TM) and grass mulch (GM). The BM treatment consistently increased the soil moisture and temperature, resulting in earlier emergence, as well as increased plant height and plant biomass, compared to the WM treatment. Compared to WM, the two-years mean yield of maize with BM, TM and GM were recorded to be increased by 33.6%, 28.1% and 10.8%, respectively. The BM produced a maximal crop growth rate at 90 days after sowing (DAS) as specified by a greater leaf area index. Transpiration rate and leaf stomatal conductance were significantly higher with BM and TM than with WM, however, the BM treatment showed the highest net photosynthetic rate in both years. Net income for the BM treatment was the highest (USD 1226 ha−1) of all the treatments and USD 335 ha−1 greater than WM. As growth, yield and net income of maize were improved with BM, therefore this treatment was found to be the most effective for maize production in rain-fed conditions. This system is evaluated at a small scale, hence to maximize its effectiveness on a large scale, a simulation design needs to be developed. [ABSTRACT FROM AUTHOR]

Water scarcity and weed infestation are major challenges to soybean production. Therefore, two field experiments were conducted in a strip plot design including three replicates in the 2019 and 2020 summer seasons at Sakha Agricultural Research Station, Agricultural Research Centre, Egypt, to investigate the effect of three irrigation levels (I0 (100%), I1 (90%), and I2 (80%)), and six weed control treatments of pendimethalin (T1), oxyfluorfen (T2), bentazon + clethodim (T3), imazethapyr (T4), hand-hoeing twice (T5), and untreated check (T6) on annual weeds, physiological traits, water relations, and yield and its components of soybean cv Giza 111. Results indicated that intermediate irrigation levels lead to the highest yield and economic return, while the herbicide program that resulted in the greatest weed control gave the highest yield. The rate of weed infestation in field experiments was 19.7 and 21.8 t ha−1 dry weights, which decreased soybean yield by 56.9 and 57.1%, compared to treatment (T4). The interactions between 100 irrigation level (I0) and imazethapyr (T4), bentazon + clethodim (T3), and hand-hoeing twice (T5) gave the highest significant values of the most studied characters. Furthermore, under 90% irrigation, all weed control treatments give the best control of weeds and the highest values of the economic criteria. [ABSTRACT FROM AUTHOR]

Intensive greenhouse vegetable production is often associated with a decline of crop productivity due to the increase of soil salinity and/or a reduction of biological fertility. The aim of the current work was to assess the effects of three organic fertilizers on morpho-physiological and agronomic traits of greenhouse lettuce as well as soil enzyme activity under poor soil quality conditions. The tested organic fertilizers (poultry manure, vinasse-based fertilizer, and insect’s frass fertilizer) were applied pre-planting at the same equivalent nitrogen (N) rate (90 kg N ha−1). Laboratory incubation assay results showed that vinasse-based fertilizer was the most suitable fertilizer in supplying the mineral N in the short term. All fertilizers increased shoot fresh and dry weight compared to unfertilized control with a more pronounced effect (+75%) with vinasse-based fertilizer and insect’s frass. Insect frass reduced by 27% the leaf nitrate concentration in comparison with the other treatments. The toxic heavy metal Pb was 46% lower in all organically fertilized lettuce leaves. Soil enzymatic activities of acid phosphatase, alkaline phosphatase, arylsulfatase (ArS), N-acetyl-β-D-glucosaminidase (NAGase), dehydrogenase, and total hydrolase (THA) were enhanced by poultry manure and insect’s frass in comparison with unfertilized control while vinasse-based fertilizer increased ArS, NAGase, and THA. Taken together, our data demonstrate that the application of organic fertilizers especially vinasse-based fertilizer and insect’s frass during intensive crop production is a suitable approach for mitigating the negative impact of soil salinity, enhancing soil biological fertility, and improving agronomic performance of greenhouse lettuce.

Canker symptoms were observed on almond trees in the Fez-Meknes region, Morocco. Isolations were conducted from the infected branch and trunk showing internal and external brown lesions. Four representative fungal isolates were screened, and their identities were confirmed by cultural traits and sequence analysis of DNA using two genes, the ITS region (internal transcribed spacer) and calmodulin (cmdA). The identified fungi were Curvularia hawaiiensis, Fusarium ambrosium, Lasiodiplodia theobromae, and Chondrestereum purpureum. The pathogenicity test on almond twigs revealed that these species were pathogenic to their host with different degrees of virulence, with Lasiodiplodia theobromae as the most virulent causing the longest necrotic lesion (285.17 mm) and the death of twigs. Physiological traits analysis of the above-mentioned fungi showed that the optimum mycelium growth response at different temperatures varies from 10 to 35 °C, while the pH ranges between 3.0 and 8.0. This study confirms the presence of canker pathogens on almond trees, which will contribute valuable information to improve the understanding of the contemporary status of almond trees, thus helping the improvement of the management of almond orchards. To our knowledge, all these fungi represent new records in Morocco and some of them are confirmed on the almond trees for the first time in the world.

The capture and utilization of rainwater by crops under various mulching conditions have great importance in agriculture production systems, especially in dry-prone regions. Understanding the effect of mulching on rainwater use efficiency growth and yield of a crop is very important. For this purpose, field experiments were conducted in 2017 and 2018 to evaluate the potential of ridge-furrow mulching on maize growth and development under rain-fed conditions. The field study compared four treatments, i.e., ridge-furrow without mulch (WM), black plastic mulch (BM), transparent plastic mulch (TM) and grass mulch (GM). The BM treatment consistently increased the soil moisture and temperature, resulting in earlier emergence, as well as increased plant height and plant biomass, compared to the WM treatment. Compared to WM, the two-years mean yield of maize with BM, TM and GM were recorded to be increased by 33.6%, 28.1% and 10.8%, respectively. The BM produced a maximal crop growth rate at 90 days after sowing (DAS) as specified by a greater leaf area index. Transpiration rate and leaf stomatal conductance were significantly higher with BM and TM than with WM, however, the BM treatment showed the highest net photosynthetic rate in both years. Net income for the BM treatment was the highest (USD 1226 ha−1) of all the treatments and USD 335 ha−1 greater than WM. As growth, yield and net income of maize were improved with BM, therefore this treatment was found to be the most effective for maize production in rain-fed conditions. This system is evaluated at a small scale, hence to maximize its effectiveness on a large scale, a simulation design needs to be developed.

Water scarcity and weed infestation are major challenges to soybean production. Therefore, two field experiments were conducted in a strip plot design including three replicates in the 2019 and 2020 summer seasons at Sakha Agricultural Research Station, Agricultural Research Centre, Egypt, to investigate the effect of three irrigation levels (I0 (100%), I1 (90%), and I2 (80%)), and six weed control treatments of pendimethalin (T1), oxyfluorfen (T2), bentazon + clethodim (T3), imazethapyr (T4), hand-hoeing twice (T5), and untreated check (T6) on annual weeds, physiological traits, water relations, and yield and its components of soybean cv Giza 111. Results indicated that intermediate irrigation levels lead to the highest yield and economic return, while the herbicide program that resulted in the greatest weed control gave the highest yield. The rate of weed infestation in field experiments was 19.7 and 21.8 t ha−1 dry weights, which decreased soybean yield by 56.9 and 57.1%, compared to treatment (T4). The interactions between 100 irrigation level (I0) and imazethapyr (T4), bentazon + clethodim (T3), and hand-hoeing twice (T5) gave the highest significant values of the most studied characters. Furthermore, under 90% irrigation, all weed control treatments give the best control of weeds and the highest values of the economic criteria.

Soil relative water content and seed plumpness have been shown to be the key factors affecting seed germination and seedling growth of rice under direct drought cropping. It remains to be determined whether seed germination and seedling growth of water-saving and drought-resistant rice (WDR) and conventional rice with the same proportion of rice seed have the same response to soil moisture changes. The purpose of this study was to investigate the seed germination and physiological characteristics of the rice cultivars Guangliangyou 1813 (GLY-1813,indica hybrid rice) and Hanyou 73 ((HY-73), WDR) with four different specific gravities (T1, T2, T3, and T4; the rice seeds were divided into four specific gravity levels by weight using saline water, the representative specific gravities were 1.2 kg m−3, respectively), at five soil moisture content gradients (soil relative water contents of 10–20%, 20–40%, 40–60%, 60–80%, and 80–100%), under dry direct seeding conditions. The results showed that GLY-1813 had a higher germination potential, germination and seedling emergence rates, greater root dry weight, seedling dry weight, root oxidation activity, and chlorophyll content, and lower malondialdehyde (MDA) content when the soil relative water content was 20–40% or 40–60%. Cultivar HY-73 had the highest germination rate and seedling physiological activity at 20–40% relative water content; its growth vigor was better than that of GLY-1813 at the same soil moisture level. In conclusion, the soil relative water content for seed germination of HY-73 was 20–40%, which was less than that of GLY-1813. When soil relative water content was sufficient for seed germination and growth, the higher the plumpness of the rice seed, the easier it was to resist the negative effects of an adverse growth environment.

This study aimed to evaluate and compare the physiological traits, productivity, and seed quality of nine faba bean varieties grown in a field trial under the Boreal climate conditions. A two-factor field experiment was laid out in a split-plot design: The seeds in the main plots were sown and treated with seed fungicide (SF) and untreated (without SF) (factor A). The sub-plots were assigned to nine varieties (factor B). The physiological traits of faba bean significantly varied among the varieties, and the behavior of faba bean varieties differed between the two growing seasons. The values of physiological traits for varieties Julia and Boxer significantly surpassed the trial mean under wet conditions, while the trait values for Fuego and Bioro were surpassed under conditions of a lack of moisture. Fungicidal seed treatment had a negligible effect on the physiological traits, while it had a significant negative influence on the leaf area index at the beginning of the flowering stage. SF had a noticeable effect on seed yield only for the varieties Nida DS and Fuego. The findings of the study revealed that Fuego and Isabell were the most suitable faba bean varieties for cultivation in the Boreal climate zone as they were distinguished from the other tested ones by the highest seed yields.

Weedy rice is one of the most common weeds in rice cultivation in many rice areas throughout the world and it is able to cause significant yield reductions. Weedy rice is characterized by a high biological diversity that permits different populations to be identified on the basis of their morphological and physiological traits. This variability contributes to its success in different environments and allows different abiotic stresses, which are intensified by climate change, to be faced. Taller plants, enhanced tillering, seed shattering and the presence of red pericarp, variable hull coloration and awn morphology, linked to a deeper seed dormancy, are some of the traits that help weedy rice to spread in changing environments. The higher phenotypic plasticity and genetic variability of weedy rice make it more able to cope with temperature variations, intermittent water availability, soil salinity, drought conditions and increased CO2 concentrations than cultivated rice. As these abiotic stresses will become more frequent in the future, weedy rice competitiveness may be higher, with a spread of infestations. Thus, the control of weedy rice should be based on an integration of different preventive and agronomic techniques, a sensible use of herbicides and the use of suitable rice varieties.

Soybean is one of the most important crops worldwide; however, its production and produced seed quality are challenged by the increasingly reported drought waves because of its relative susceptibility to drought stress conditions. Nitrogen (N) is a major macronutrient that has distinctive influence on soybean, especially if applied in correct rates. Moreover, N has an additive importance under drought stress conditions. An experiment was carried out in Debrecen, Hungary in 2017, 2018, and 2019 to investigate the sole and the combined effects of N application under different irrigation regimes on soybean physiology, yield, and its components in addition to the quality of the produced yield. Results showed that the morpho-physiological traits, in addition to the yield component traits were influenced by both fertilization rates and irrigation regimes. Most importantly, high N rate is not recommended with the absence of drought conditions as, compared to low rate, it decreased flower and pod number per plant, plant height, and seed yield. On the other hand, high N rate enhanced most traits under drought stress conditions. 100-seed weight had the highest correlation with yield, followed by flower and pod number per plant, plant height, and Normalized Difference Vegetation Index (NDVI).

In order to integrate genomics in breeding and development of drought-tolerant groundnut genotypes, identification of genomic regions/genetic markers for drought surrogate traits is essential. We used 3249 diversity array technology sequencing (DArTSeq) markers for a genetic analysis of 125 ICRISAT groundnut mini core collection evaluated in 2015 and 2017 for genome-wide marker-trait association for some physiological traits and to determine the magnitude of linkage disequilibrium (LD). Marker-trait association (MTA) analysis, probability values, and percent variation modelled by the markers were calculated using the GAPIT package via the KDCompute interface. The LD analysis showed that about 36% of loci pairs were in significant LD (p < 0.05 and r2 > 0.2) and 3.14% of the pairs were in complete LD. The MTAs studies revealed 20 significant MTAs (p < 0.001) with 11 markers. Four MTAs were identified for leaf area index, 13 for canopy temperature, one for chlorophyll content and two for normalized difference vegetation index. The markers explained 20.8% to 6.6% of the phenotypic variation observed. Most of the MTAs identified on the A subgenome were also identified on the respective homeologous chromosome on the B subgenome. This could be due to a common ancestor of the A and B genome which explains the linkage detected between markers lying on different chromosomes. The markers identified in this study can serve as useful genomic resources to initiate marker-assisted selection and trait introgression of groundnut for drought tolerance after further validation.

Alfalfa (Medicago sativa L.) is a valuable forage legume, but its production is largely affected by high temperature. In this study, we investigated the effect of heat stress on 15 alfalfa cultivars to identify heat-tolerant and -sensitive cultivars. Seedlings were exposed to 38/35 °C day/night temperature for 7 days and various parameters were measured. Heat stress significantly reduced the biomass, relative water content (RWC), chlorophyll content, and increased the electrolyte leakage (EL) and malondialdehyde (MDA) content of heat-sensitive alfalfa cultivars. However, heat-tolerant cultivars showed higher soluble sugar (SS) and soluble protein (SP) content. The heat tolerance of each cultivar was comprehensively evaluated based on membership function value. Cultivars with higher mean membership function value of 0.86 (Bara310SC) and 0.80 (Magna995) were heat tolerant, and Gibraltar and WL712 with lower membership function value (0.24) were heat sensitive. The heat tolerance of the above four cultivars were further evaluated by chlorophyll a fluorescence analysis. Heat stress significantly affected the photosynthetic activity of heat-sensitive cultivars. The overall results indicate that Bara310SC and WL712 are heat-tolerant and heat-sensitive cultivars, respectively. This study provides basic information for understanding the effect of heat stress on growth and productivity of alfalfa.

In recent years, with climate change, drought stress has been witnessed in many parts of the world. In many irrigated regions also, shortage of water supply allows only limited irrigation. These conditions have an adverse effect on the productivity of many crops including cereals such as wheat. Therefore, genetics of drought/water stress tolerance in different crops has become a priority area of research. This research mainly involves use of quantitative trait locus (QTL) analysis (involving both interval mapping and association mapping) for traits that are related to water-use efficiency. In this article, we briefly review the available literature on QTL analyses in wheat for traits, which respond to drought/water stress. The outlook for future research in this area and the possible approaches for utilizing the available information on genetics of drought tolerance for wheat breeding are also discussed.

Soil relative water content and seed plumpness have been shown to be the key factors affecting seed germination and seedling growth of rice under direct drought cropping. It remains to be determined whether seed germination and seedling growth of water-saving and drought-resistant rice (WDR) and conventional rice with the same proportion of rice seed have the same response to soil moisture changes. The purpose of this study was to investigate the seed germination and physiological characteristics of the rice cultivars Guangliangyou 1813 (GLY-1813,indica hybrid rice) and Hanyou 73 ((HY-73), WDR) with four different specific gravities (T1, T2, T3, and T4; the rice seeds were divided into four specific gravity levels by weight using saline water, the representative specific gravities were <1.0, 1.0–1.1, 1.1–1.2 and >1.2 kg m−3, respectively), at five soil moisture content gradients (soil relative water contents of 10–20%, 20–40%, 40–60%, 60–80%, and 80–100%), under dry direct seeding conditions. The results showed that GLY-1813 had a higher germination potential, germination and seedling emergence rates, greater root dry weight, seedling dry weight, root oxidation activity, and chlorophyll content, and lower malondialdehyde (MDA) content when the soil relative water content was 20–40% or 40–60%. Cultivar HY-73 had the highest germination rate and seedling physiological activity at 20–40% relative water content; its growth vigor was better than that of GLY-1813 at the same soil moisture level. In conclusion, the soil relative water content for seed germination of HY-73 was 20–40%, which was less than that of GLY-1813. When soil relative water content was sufficient for seed germination and growth, the higher the plumpness of the rice seed, the easier it was to resist the negative effects of an adverse growth environment. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate and compare the physiological traits, productivity, and seed quality of nine faba bean varieties grown in a field trial under the Boreal climate conditions. A two-factor field experiment was laid out in a split-plot design: The seeds in the main plots were sown and treated with seed fungicide (SF) and untreated (without SF) (factor A). The sub-plots were assigned to nine varieties (factor B). The physiological traits of faba bean significantly varied among the varieties, and the behavior of faba bean varieties differed between the two growing seasons. The values of physiological traits for varieties Julia and Boxer significantly surpassed the trial mean under wet conditions, while the trait values for Fuego and Bioro were surpassed under conditions of a lack of moisture. Fungicidal seed treatment had a negligible effect on the physiological traits, while it had a significant negative influence on the leaf area index at the beginning of the flowering stage. SF had a noticeable effect on seed yield only for the varieties Nida DS and Fuego. The findings of the study revealed that Fuego and Isabell were the most suitable faba bean varieties for cultivation in the Boreal climate zone as they were distinguished from the other tested ones by the highest seed yields. [ABSTRACT FROM AUTHOR]

Weedy rice is one of the most common weeds in rice cultivation in many rice areas throughout the world and it is able to cause significant yield reductions. Weedy rice is characterized by a high biological diversity that permits different populations to be identified on the basis of their morphological and physiological traits. This variability contributes to its success in different environments and allows different abiotic stresses, which are intensified by climate change, to be faced. Taller plants, enhanced tillering, seed shattering and the presence of red pericarp, variable hull coloration and awn morphology, linked to a deeper seed dormancy, are some of the traits that help weedy rice to spread in changing environments. The higher phenotypic plasticity and genetic variability of weedy rice make it more able to cope with temperature variations, intermittent water availability, soil salinity, drought conditions and increased CO2 concentrations than cultivated rice. As these abiotic stresses will become more frequent in the future, weedy rice competitiveness may be higher, with a spread of infestations. Thus, the control of weedy rice should be based on an integration of different preventive and agronomic techniques, a sensible use of herbicides and the use of suitable rice varieties. [ABSTRACT FROM AUTHOR]

In order to integrate genomics in breeding and development of drought-tolerant groundnut genotypes, identification of genomic regions/genetic markers for drought surrogate traits is essential. We used 3249 diversity array technology sequencing (DArTSeq) markers for a genetic analysis of 125 ICRISAT groundnut mini core collection evaluated in 2015 and 2017 for genome-wide marker-trait association for some physiological traits and to determine the magnitude of linkage disequilibrium (LD). Marker-trait association (MTA) analysis, probability values, and percent variation modelled by the markers were calculated using the GAPIT package via the KDCompute interface. The LD analysis showed that about 36% of loci pairs were in significant LD (p < 0.05 and r2 > 0.2) and 3.14% of the pairs were in complete LD. The MTAs studies revealed 20 significant MTAs (p < 0.001) with 11 markers. Four MTAs were identified for leaf area index, 13 for canopy temperature, one for chlorophyll content and two for normalized difference vegetation index. The markers explained 20.8% to 6.6% of the phenotypic variation observed. Most of the MTAs identified on the A subgenome were also identified on the respective homeologous chromosome on the B subgenome. This could be due to a common ancestor of the A and B genome which explains the linkage detected between markers lying on different chromosomes. The markers identified in this study can serve as useful genomic resources to initiate marker-assisted selection and trait introgression of groundnut for drought tolerance after further validation. [ABSTRACT FROM AUTHOR]

Alfalfa (Medicago sativa L.) is a valuable forage legume, but its production is largely affected by high temperature. In this study, we investigated the effect of heat stress on 15 alfalfa cultivars to identify heat-tolerant and -sensitive cultivars. Seedlings were exposed to 38/35 °C day/night temperature for 7 days and various parameters were measured. Heat stress significantly reduced the biomass, relative water content (RWC), chlorophyll content, and increased the electrolyte leakage (EL) and malondialdehyde (MDA) content of heat-sensitive alfalfa cultivars. However, heat-tolerant cultivars showed higher soluble sugar (SS) and soluble protein (SP) content. The heat tolerance of each cultivar was comprehensively evaluated based on membership function value. Cultivars with higher mean membership function value of 0.86 (Bara310SC) and 0.80 (Magna995) were heat tolerant, and Gibraltar and WL712 with lower membership function value (0.24) were heat sensitive. The heat tolerance of the above four cultivars were further evaluated by chlorophyll a fluorescence analysis. Heat stress significantly affected the photosynthetic activity of heat-sensitive cultivars. The overall results indicate that Bara310SC and WL712 are heat-tolerant and heat-sensitive cultivars, respectively. This study provides basic information for understanding the effect of heat stress on growth and productivity of alfalfa. [ABSTRACT FROM AUTHOR]