Exploiting Plant Functional Diversity in Durum Wheat–Lentil Relay Intercropping to Stabilize Crop Yields under Contrasting Climatic Conditions

Relay intercropping is considered a valuable agroecological practice to increase and stabilize crop yields while ensuring the provision of several ecosystem services as well as sustainability and resilience to changing climatic conditions. However, farmers are still reluctant in the use of intercropping practices since there is a huge knowledge gap regarding the time of sowing, sowing ratio, crop stand density, and cultivar choice. In this study, we carried out a 3-year field experiment in Central Italy to assess the effect of relay intercropping on the agronomic performance and competitiveness of winter durum wheat (Triticum durum Desf. cv. Minosse) and spring lentil (Lens culinaris Medik. cv. Elsa) under a low-input management system, comparing different crop stand types (monocrop vs. intercrop) and target plant densities (350 plants m2—full dose vs. 116 plants m2—1/3 dose). The results revealed that intercropping increased grain yield compared to monocropping: significantly (p < 0.0001) against both monocrops in 2021 and non-significantly against durum wheat in 2019 and 2020. Yield advantage in both intercropping systems ranged between 164 and 648%. Durum wheat competitiveness was stronger in 2019 and 2021, while lentil was the most competitive component in 2020. Intercropping favored P accumulation in durum wheat shoots. There was no difference in grain yield of both crops between the highly- and lowly-dense system in 2020 and 2021. Both intercropping strategies were as effective as mechanical hoeing in controlling weeds and proved beneficial in stabilizing lentil productivity. Further economic analysis capturing the additional costs incurred in intercropping and mechanical weeding would highlight the magnitude of profitability of these systems.

Phenotypic Characterization of Some Durum Wheat (Triticum durum Desf.)Genotypes Growing under Semi-Arid Conditions

Breeders are permanently looking for an efficient method of developing genotypes with improved yield. The aim of this study was to evaluate the performance of some durum wheat genotypes, the study of the correlations between traits and the direct effect of each trait on final grain yield. Twenty genotypes of durum wheat (Triticum durum Desf.) were planted in the experimental fields of INRAA, Setif, Algeria in (2016 –2017) crop season. The genotypes tested were grown in a randomized block design with three replications. The analyses of variance (ANOVA) demonstrate the existence of genetic diversity between genotypes tested. In addition, significant and positive correlations were registered between grain yield (GY) and days to heading (DH), number of spikes per square meter (NSM) and number of kernels per spike (NKS). The path analysis (PA) demonstrates positive and significant direct effects of the number of spikes per square meter (NSM), thousand kernels weight (TKW) and number of kernels per spike (NKS) on grain yield. Overall, the results proved that the genotypes Rezzak, Ofanto and BIDI 17 have the best ranking with the highest grain yield, and these can be recommended as the best genotypes for some in this area. In addition, the Principal Component Analysis (PCA) proved that the genotypes Rezzak, Bidi17, Ofanto, Kebir and Adnan 2 are very suitable genotypes for growing under semi-arid conditions.

Canopy Cover Temperature & Drought Tolerance Indices in Durum Wheat (Triticum durum Desf.) Genotypes under Semi-arid Condition in Algeria

This experiment was carried out at Setif Agricultural Experimental Station in Algeria during 2017–2018 crop season using five cultivars (Triticum durum Desf.) to determine differences in the relationship between (CT and drought resistance indices values based on their difference in yielding under irrigated and non-irrigated conditions and sown in a random block design with three replications. Our study aim to determine differences in the relationship between CT and drought resistance indices values and grain yield GY under both conditions to evaluate the effect of canopy temperature in drought tolerance of durum wheat. Five durum wheat (Triticum durum Desf.) genotypes were studied based on their difference in yielding under irrigated and non-irrigated conditions in conception of a random block design with three replications. The following measurements were applied: GY, CT canopy cover temperature depression CTD and seven drought tolerance indices (HM-SSI-GMP-STI-YSI-MP-TOL). ANOVA showed that genotype effect and irrigation regime effect were highly and significantly on CT and CTD under both stressed (s) and watered (i) conditions. The interaction Genotype×irrigation regime was significant for CT and CTD. PCA showed that CTDs was related with HM, GMP, STI, and MP in indication of drought tolerance, where CTDi was related with TOL and SSI in indication of drought sensitivity. A negative correlation showed between CT and CTD, higher values ​​of CT compared to environmental temperature implies negative values ​​of CTD which indicates drought sensitivity; on the other hand, CT values ​​lower than environmental temperature implies positive CTD values ​​indicating drought tolerance.

The structure of productivity elements of durum wheat varieties of Saratov selection

The objects of the study were plants of 14 varieties of durum wheat Triticum durum Desf., permitted for use at different times in the period from 1975 to 2014. An analysis of the elements of ear productivity in durum wheat plants of Saratov varieties under the conditions of 2020 was carried out. The varietal features of the development of the spike of the main shoot were revealed according to a number of characteristics: the number of spikelets in a spike, the number of grains in an ear, the weight of a grain, the number of ungrained and grained spikelets. The height of the plant and the length of the spike were measured. On the basis of the data obtained, the selection indices were calculated – the Canadian index, the Mexican index, the index of the linear density of the ear, the morphogenetic index of productivity. A cultivar with a balanced type of morphogenetic systems was revealed in terms of the elements of ear productivity – the number of spikelets, the number of caryopses and their weight – Luch 25. This cultivar is characterized by the most developed embryonic shoot among the studied cultivars, as well as the maximum length of the embryonic root system and a high growth rate root system of the seedling.

Genome-Wide Identification, Characterization and Expression Pattern Analysis of the γ-Gliadin Gene Family in the Durum Wheat (Triticum durum Desf.) Cultivar Svevo

Very recently, the genome of the modern durum wheat cv. Svevo was fully sequenced, and its assembly is publicly available. So, we exploited the opportunity to carry out an in-depth study for the systematic characterization of the γ-gliadin gene family in the cv. Svevo by combining a bioinformatic approach with transcript and protein analysis. We found that the γ-gliadin family consists of nine genes that include seven functional genes and two pseudogenes. Three genes, Gli-γ1a, Gli-γ3a and Gli-γ4a, and the pseudogene Gli-γ2a* mapped on the A genome, whereas the remaining four genes, Gli-γ1b, Gli-γ2b, Gli-γ3b and Gli-γ5b, and the pseudogene Gli-γ4b* mapped on the B genome. The functional γ-gliadins presented all six domains and eight-cysteine residues typical of γ-gliadins. The Gli-γ1b also presented an additional cysteine that could possibly have a role in the formation of the gluten network through binding to HMW glutenins. The γ-gliadins from the A and B genome differed in their celiac disease (CD) epitope content and composition, with the γ-gliadins from the B genome showing the highest frequency of CD epitopes. In all the cases, almost all the CD epitopes clustered in the central region of the γ-gliadin proteins. Transcript analysis during seed development revealed that all the functional γ-gliadin genes were expressed with a similar pattern, although significant differences in the transcript levels were observed among individual genes that were sometimes more than 60-fold. A progressive accumulation of the γ-gliadin fraction was observed in the ripening seeds that reached 34% of the total gliadin fraction at harvest maturity. We believe that the insights generated in the present study could aid further studies on gliadin protein functions and future breeding programs aimed at the selection of new healthier durum wheat genotypes.

Starting material for breeding spring emmer (Triticum dicoccum shrank.) of groats use

Aim. To explore sources of high groats properties among the genetic diversity of emmer and related species. Methods. Biochemical: The protein content was determined by Kjeldahl digestion; the starch content – by infrared spectroscopy. Technological: the vitreousness was determined by cutting 100 caryopses and expressed as percent- ages. The hull content, expressed in percent, was estimated as the ratio of hulled caryopses to the total of fully threshed ones. The gluten content and quality were assessed by manual washing-out. The hardness was determined on a YPD-300 hardness tester (Ltpm China) as the force in newtons required for caryopsis destruction. Emmer groats were obtained on a laboratory peeler UShZ-1. The groats properties were evaluated according to the method described in a utility model patent No. 129205. Statistical: the significance of differences between accessions was assessed using the Mann-Whitney test for small samples with unknown distribution. Two-factor analysis of vari- ance considered 2 factors – genotype and year conditions. Pearson’s test was used in the correlation analysis. The variability of traits was assessed by the coefficient of variation (CV). Results. The yields of emmer and durum wheat accessions and varieties as well as lines derived from emmer-wheat hybrids were measured and analyzed in 2016–2019. The yields of most emmer accessions (except for T. timopheevii) were similar to that of the check em- mer variety Holikovska (286 ± 15 g/m2). The highest contents of protein and gluten were found in T. timopheevii (18.1 ± 0.4 % and 40.5 ± 1.8 %, respectively), Triticum durum Desf. var. falcatomelanopus Jakubz. & Filat. (17.5 ± ± 1.0 % and 40.4 ± 1.4 %), autochthonous variety Polba 3 (16.8 ± 0.1 % and 36.9 ± 1.1 %), and line 10–139 (14.8 ± 0.8 % and 29.0 ± 2.4 %). The gluten quality of most lines, derived from crossing spring emmer with durum wheat, corresponds to quality group I (good), and the gluten deformation index (GDI) is 50–75 units. T. timopheevii and T. durum var. falcatomelanopus were noticeable for vitreousness (99 ± 1 % and 75 ± 5 %, respec- tively). The grain hardness of the accessions under investigation varied from 151 ± 15 N in variety Romanivska to 286 ± ± 3 N in T. timopheevii. Lines 10–79 (255 ± 6 N), 10–65 (220 ± 10 N) and T. durum var. falcatomelanopus (268 ± 6 N) were characterized by high hardness, which exceeded that of durum wheat variety Spadshchyna (152 ± ± 13 N). High outputs of groats were intrinsic to line 10–139 (96.2 ± 0.8 %), line 10–79 (90.6 ± 0.8 %), T. timopheevii (92.0 ± 0.1 %), and durum wheat Spadshchyna (91.4 ± 0.5 %). All the studied accessions showed low variability (

Starting material for breeding spring emmer (Triticum dicoccum shrank.) of groats use

Aim. To explore sources of high groats properties among the genetic diversity of emmer and related species. Methods. Biochemical: The protein content was determined by Kjeldahl digestion; the starch content – by infrared spectroscopy. Technological: the vitreousness was determined by cutting 100 caryopses and expressed as percent- ages. The hull content, expressed in percent, was estimated as the ratio of hulled caryopses to the total of fully threshed ones. The gluten content and quality were assessed by manual washing-out. The hardness was determined on a YPD-300 hardness tester (Ltpm China) as the force in newtons required for caryopsis destruction. Emmer groats were obtained on a laboratory peeler UShZ-1. The groats properties were evaluated according to the method described in a utility model patent No. 129205. Statistical: the significance of differences between accessions was assessed using the Mann-Whitney test for small samples with unknown distribution. Two-factor analysis of vari- ance considered 2 factors – genotype and year conditions. Pearson’s test was used in the correlation analysis. The variability of traits was assessed by the coefficient of variation (CV). Results. The yields of emmer and durum wheat accessions and varieties as well as lines derived from emmer-wheat hybrids were measured and analyzed in 2016–2019. The yields of most emmer accessions (except for T. timopheevii) were similar to that of the check em- mer variety Holikovska (286 ± 15 g/m2). The highest contents of protein and gluten were found in T. timopheevii (18.1 ± 0.4 % and 40.5 ± 1.8 %, respectively), Triticum durum Desf. var. falcatomelanopus Jakubz. & Filat. (17.5 ± ± 1.0 % and 40.4 ± 1.4 %), autochthonous variety Polba 3 (16.8 ± 0.1 % and 36.9 ± 1.1 %), and line 10–139 (14.8 ± 0.8 % and 29.0 ± 2.4 %). The gluten quality of most lines, derived from crossing spring emmer with durum wheat, corresponds to quality group I (good), and the gluten deformation index (GDI) is 50–75 units. T. timopheevii and T. durum var. falcatomelanopus were noticeable for vitreousness (99 ± 1 % and 75 ± 5 %, respec- tively). The grain hardness of the accessions under investigation varied from 151 ± 15 N in variety Romanivska to 286 ± ± 3 N in T. timopheevii. Lines 10–79 (255 ± 6 N), 10–65 (220 ± 10 N) and T. durum var. falcatomelanopus (268 ± 6 N) were characterized by high hardness, which exceeded that of durum wheat variety Spadshchyna (152 ± ± 13 N). High outputs of groats were intrinsic to line 10–139 (96.2 ± 0.8 %), line 10–79 (90.6 ± 0.8 %), T. timopheevii (92.0 ± 0.1 %), and durum wheat Spadshchyna (91.4 ± 0.5 %). All the studied accessions showed low variability (

Cultivars and lines from ICARDA in spring durum wheat (Triticum durum Desf.) breeding in the Lower Volga region

Background. In 1991, under the cooperation agreement, the Federal Center of Agriculture Research (FCAR) of the South-East Region received the first improved accessions from the International Center for Agricultural Research in the Dry Areas (ICARDA). The objective of this work was to study the source material developed under comparable conditions of dryland agriculture and include the best accessions in scientific breeding programs.Material and methods. The presented data resulted from the study of spring durum wheat cultivars and lines from ICARDA (Aleppo, Syria), conducted in 1991–1998. Accessions with the best indicators of grain quality, adapted to the conditions of the Lower Volga, were selected and included into the crossing program. Grain analysis was carried out using the conventional methods for durum wheat as well as those modified by the Spring Durum Wheat Breeding Laboratory of the FCAR of the South-East.Result and conclusion. Many years of work led to identifying 22 lines of spring durum wheat, selected in the breeding nursery of the Main Competitive Trails (MCT) and in different years involved in complex multistep hybridization. The spring durum wheat cultivar ‘Lilek’ was included into the State Register for Selection Achievements in 2009, while cv. ‘Tamara’ was submitted to the State Variety Trials in 2020.