In the face of climate change, developing resilient crops is crucial for global food security in the 21st century to feed a growing population. Lentil (Lens culinaris Medikus) plays a vital role in ensuring global food and nutritional security. Traits like early flowering enable the crop to mature faster, thereby shortening the growing window and reducing yield losses caused by moisture and heat stresses during the reproductive phase. However, issues like limited genetic diversity in this trait remain unaddressed. To address this gap, our study aims to comprehensively assess genetic variability and trait associations in 158 lentil accessions. In the present study, we observed significant variations for days to 50% flowering (67–90 days), days to maturity (109–122 days) and 100 seed weight (1.69–2.68 g) throughout a period of two consecutive years (2020–2021 and 2021–2022). The observed variability in these traits offers a valuable avenue for the improvement of lentil yield through targeted selection and hybridization. Additionally, correlation analysis showed negative correlation between days to 50% flowering and grain yield per plant, while plant height had a significant (P < 0.01) positive correlation with all traits except yield per plant. Furthermore, we identified specific germplasm with exceptional traits that hold significant potential for future breeding programmes. The genotypes EC 223197-A and EC 267696 were identified for early flowering with high yield, and other genotypes that were identified for various traits would serve as breeding material for the introgression of these traits into elite cultivars.

To maximize seed longevity, seeds should be harvested at optimal maturity, that is, when seeds have acquired maximum physiological quality before deterioration begins. The aim of this study was to map the variation in temporal patterns of lentil (Lens culinaris Medik.) seed quality development when grown across four regeneration environments, which differ in the level of temperature and humidity control throughout the growing season, at the Australian Grains Genebank. Seeds of two lentil accessions (76080 and 76072) were harvested at different stages throughout development, commencing at 21 d after 50% anthesis until a maximum of 130 d. At each harvest, physiological quality traits, including germinability (fresh and dried seeds) and seed longevity, were determined, as well as seed dry weight and moisture content. Seeds of both accessions, and in all environments, started to accumulate physiological quality early on in development but did not reach their maximum until 3–54 d after mass maturity. The temporal patterns of desiccation tolerance and storage longevity were highly influenced by the environmental conditions during the maturation drying phase, affecting both ‘when’ maximum quality was attained and for how long it was maintained, thereafter. Seeds did not show a typical developmental response, rather variation was observed in seed quality development both between and within accessions grown in the different environments. The poorest storage longevity was seen when seeds of both accessions were grown in the cooler, temperature-controlled glasshouse, and the maximum longevity was observed in the warmer, semi-protected environments of the green and the big igloo for accessions 76080 and 76072, respectively.

Genotyping of lentil plant genetic resources holds the promise to increase the identification and utilization of useful genetic diversity for crop improvement. The International Center for Agriculture Research in the Dry Areas (ICARDA) lentil reference set plus collection of 176 accessions was genotyped using genotyping-by-sequencing (GBS) and 22,555 SNPs were identified. The population structure was investigated using Bayesian analysis (STRUCTURE, k = 3) and principal component analysis. The two methods are in concordance. Genome-wide association analysis (GWAS) using the filtered SNP set and ICARDA historical phenotypic data discovered putative markers for several agronomic traits including days to first flower, seeds per pod, seed weight and days to maturity. The genetic and genomic resources developed and utilized in this study are available to the research community interested in exploring the ICARDA reference set plus collection using GWAS.

This study examined energy, greenhouse gas emission and ecological footprint analysis (EFA) of chickpea and lentil cultivation with different mechanization production systems. In lentil production, except for tillage operations, other operations are performed manually and the remaining straw is burned in the field; while in chickpea production, most of the agricultural operations are mechanized and residues are collected, baled and transferred to the warehouse for animal feed. In this paper, for the first time, some of the sustainability indicators are investigated and compared in two different legume production systems. Energy productivity and net energy for chickpea and lentil production were calculated at 0.036, 0.161 and 2373 and 5900 MJ per hectare, respectively. The CO2 emission and ecological carbon footprint were 173 kg CO2−eq and 0.15 global hectare for lentil and 484 and 0.87 for chickpea production. Totally, due to excessive consumption of diesel fuel and lack of proper management, the social cost of emission from straw baling in chickpea production (27.65 dollars per hectare) was higher than burning straw in lentil production (8.77). Multi-objective genetic algorithm results showed the potential of minimizing diesel fuel and fertilizer consumption and no chemical for chickpea production. Overall audition results of two different production systems revealed that traditional lentil production is more sustainable. Therefore, implementations of modern agricultural practices alone are not enough to achieve sustainability in agricultural production systems.

Cultivated lentil suffers yield loss from stemphylium blight, caused by Stemphylium botryosum Wallr. Identification of sources of stemphylium blight resistance and knowledge of the mode of inheritance of resistance are important for developing resistant cultivars. The interspecific recombinant inbred line (RIL) population developed from a cross between the moderately resistant parent Lens culinaris cv. ‘Eston’ and the resistant parent L. ervoides (Brign.) Grande accession IG 72815 was evaluated for stemphylium blight resistance under controlled conditions at the University of Saskatchewan, Saskatoon, Canada, and under field conditions at the Pulses Research Centre (PRC), Ishurdi, Bangladesh. We hypothesized that resistance from both parents will lead to transgressive segregation indicative of pyramiding of resistance genes from the same. However, no resistant transgressive segregants were observed in the RIL population. A large proportion (50%) of the RILs had disease severity levels similar to the resistant parent IG 72815 in experiments conducted under natural disease pressure in Bangladesh. Under controlled conditions in Saskatoon, 38% of RILs had resistance levels similar to IG 72815. Across all environments, 14 RILs consistently had resistance levels similar to IG 72815. The distribution of disease severity scores for all RILs indicated polygenic inheritance of stemphylium blight resistance in the population. RILs with consistent resistant reactions should prove useful for lentil improvement programmes. This will contribute to increasing the productivity of lentil crops in North America and the Indo-Gangetic region, which account for more than 68% of world lentil production.

Anthracnose caused by Colletotrichum lentis is an important fungal disease of lentil in western Canada. Two known pathogenic C. lentis races, race 0 and race 1 have been identified and current cultivars of lentil have little or no resistance to the virulent race 0. Seven Lens culinaris subsp. culinaris landrace accessions were previously reported to have resistance to C. lentis race 0. In this study, accession VIR-2633, with reported resistance to both races of C. lentis, and seven accessions were assessed for race 0 resistance relative to LR-59-81, an interspecific line derived from a L. culinaris subsp. culinaris × Lens ervoides cross. The results showed a lack of effective resistance to race 0 among the tested L. culinaris accessions when compared to that of LR-59-81. A few sublines displayed modest improvements in resistance compared to the susceptible check ‘Eston’, but were significantly more susceptible than LR-59-81. Moreover, screening of the sublines of accession VIR-2633 identified 12 sublines with resistance to race 1, but all VIR-2633 sublines were susceptible to race 0. The study underlined the importance of wild lentil germplasm for broadening the genetic base of cultivated lentil and their usefulness in disease screening experiments as positive checks.

The most important objective of lentil breeding programs is to develop new genotypes that are genetically more productive. Besides, it is necessary that the varieties obtained have short flowering cycles to allow the later sowing of summer crops. Selection is based through phenotypic means; however, we argue it should be based on genetic or breeding values because quantitative traits are often influenced by environments and genotype–environment interactions. The objectives of this study were to: (i) identify genotypes with the highest merit; (ii) estimate genetic parameters to know the genetic control of morphological traits in macrosperma and microsperma lentil types using best linear unbiased prediction (BLUP). Twenty-five recombinant inbred lines (RILs) from six F4 families selected on the basis of precocity and high yields were tested in four environments for important quantitative traits. The analysis of variance showed significant differences between genotypes, environments, and genotype–environment interactions for all the traits. Seven macrosperma- and two microsperma-type RILs were selected. Based on average ranking from breeding values and molecular data obtained with sequence-related amplified polymorphism (SRAP), the same genotypes were selected. Genotypic coefficients of variation, heritability across and by environment, and genetic correlation coefficients using BLUP were obtained. According to our results BLUP could replace molecular analysis methods because the selection process was simpler, more cost-effective, and more accurate. The breeding value of parents would give a better ranking of their genetic value than would their phenotypic value; therefore, the selection efficiency would be enhanced and the genetic gain would be more predictable. The selected genotypes could become potential commercial varieties or be used as parental lines in future hybridization programs.

Declining pulse production has caused wide concern in recent years. A field experiment was conducted to investigate effects of balance fertilizers based on soil test values and targeted yield equations on soil biological activities, soil quality, nutrient acquisition and grain yield of lentil. Treatments included the use of farmyard manure (FYM), bio-inoculants and inorganic fertilizers at different rates and combinations. The results revealed significant improvement in nodulation, microbial counts, microbial biomass carbon (MBC), soil respiration, soil enzymes and soil organic carbon (SOC) with integrated approaches (i.e. fertilizer plus FYM or bio-inoculants); these improvements led to achievement of the specific target yield of 1.50 t/ha. Although the highest yield was achieved with fertilizers applied for a target yield of 2.0 t/ha, there was significant decline in nodulation, microbial counts, MBC, soil respiration, soil enzymes, SOC and soil quality. Correlation between soil quality index (SQI) and grain yield suggested a significant influence of balanced fertilization based on soil tests and target yield. Principal component analysis revealed the average contribution of soil quality indicators towards SQI was in descending order of SOC > acid phosphatase activity > total culturable fungi > available phosphorus > BMC, which are crucial for sustainable lentil production in alluvial soils.

An estimation of the critical period of weed control is helpful in formulating appropriate weed-control strategies. A regression approach is presented to estimate the thresholds of critical period of weed control and time of equal interference (or time of onset of competition). In this approach, yields were either a linear or logistic function of the duration of weed-free and weed-infested periods. Confidence intervals of the thresholds of critical period and time of equal interference were determined for the linear model. An approximation to the standard error of critical period and associated confidence interval were given for any general form of the model. The method was applied to estimate the critical period of weed control in rainfed lentil using data from four field experiments conducted in Jordan. The relationship of yield with the duration of weed-free period was described by a linear function, whereas the relationship with the duration of weed-infested period showed a better fit with a logistic function. To maintain 90% of maximum seed yield, the maximum time allowed to let weeds grow after the crop emergence varied over locations from 4.8 to 5.8 wk. The same level could be achieved if the crop is kept free of weeds from its emergence until 12.1 to 14.1 wk; while the time when the same amount of yield would be achieved under both approaches varied from 7.7 to 9.3 wk after crop emergence. For straw yield, the time to get 90% of the maximum yield could vary over location from a maximum of 4.5 to 8.0 wk under weed-infestation and from at least 11.5 to 13.5 wk when weed-free. The time to achieve the same amount of straw under two systems of competition varied from 6.5 to 9.9 wk after crop emergence. One of the four experiments showed a longer critical period than the others for seed and straw yields.

The potential of imazethapyr as a selective herbicide in four pulse crops was investigated at Melfort, Saskatchewan in 1988 and 1989. Lentil, field pea, faba bean and annual vetch were tolerant to imazethapyr applied preemergence to a silty clay loam soil at 0.05, 0.10, 0.15, and 0.20 kg ai ha-1. Postemergence treatments above 0.05 kg ha-1, however, stunted lentil and vetch in both years. Environmental factors, the dominant weed in the experimental site, as well as timing of application strongly influenced the performance of imazethapyr. Seed yield increases observed with imazethapyr treatments, compared to metribuzin or untreated check, were greater in 1989 when wild oat was the dominant weed and moisture was not a limiting factor in the early stages of crop development, than in 1988 when field pennycress was the dominant weed. Mean seed yield for all imazethapyr treatments, compared to the check, increased 0 and 930%, 24 and 89%, 21 and 600%, and 47 and 44% in 1988 and 1989, for lentil, field pea, faba bean and vetch, respectively. Significant increases in lentil seed density, seed size, and germination were also obtained though protein content decreased 2%.

Dicamba and 2,4-D, which are used prior to seeding in conservation tillage systems, were applied in late fall and early spring to determine their residual effect on subsequent spring-seeded crops. The herbicides 2,4-D ester and 2,4-D amine with dicamba or glyphosate, applied 0 or 15 d prior to spring seeding, damaged canola, peas, lentils, and alfalfa. The legumes were damaged by spring-applied dicamba. There was also a slight reduction in the total dry matter yield of wheat and barley by 2,4-D applied in spring prior to seeding. All crops tested, except lentils, were tolerant of recommended fall applications of 2,4-D for the control of winter annual flixweed and field pennycress.

Lens culinaris Medik. ssp. culinaris is the only cultivated species in the genus Lens. Intensive selection pressure to develop new cultivars, a narrow genetic base, co-evolution of pathogens to partially resistant cultivars and other factors have accelerated susceptibility to different fungal diseases in this species. Few sources for resistance to stemphylium blight (SB) caused by Stemphylium botryosum Wallr. exist among commercial lentil cultivars. A total of 70 accessions were selected from seven species of the genus Lens to screen for SB resistance. The L. culinaris accessions were screened in four different environments, and the accessions of Lens ervoides, L. culinaris ssp. orientalis, Lens tomentosus,Lens nigricans, Lens odemensis and Lens lamottei in growth chamber or greenhouse experiments to identify resistance sources for potential use in lentil breeding. A highly aggressive isolate of SB was used as an inoculum to screen them under controlled conditions. Lentil cultivars ‘Eston’ (resistant) and ‘CDC Glamis’ (susceptible) were used as checks with consistent results in all experiments. Most of the L. culinaris accessions were susceptible to SB, whereas more than 70% of the wild lentil accessions had disease severity scores equal to or significantly lower than that of the SB-resistant check ‘Eston’. Some wild species accessions previously identified with resistance to anthracnose (Colletotrichum truncatum) and ascochyta blight (Ascochyta lentis) were also highly resistant to SB. The highest frequency of resistance to SB was found in L. lamottei followed by L. ervoides of the secondary gene pool. These sources can potentially be used to develop new commercial cultivars with multiple or single disease resistance.

Colonization of a novel plant by herbivorous insects is frequently accompanied by genetic changes that progressively improve larval or adult performance on the new host. This study examined the genetic basis of adaptation to a marginal host (lentil) by the seed beetle Callosobruchus maculatus (F.). Quasi-natural selection in the laboratory rapidly increased the tendency to oviposit on lentil. The mode of inheritance of this increase in host acceptance was determined from crosses between three lentil-adapted lines and a line maintained on the ancestral host, mung bean. In each set of crosses, females from the lentil lines laid two to three times more eggs on lentil than did females from the mung-bean line. Hybrid females consistently displayed an intermediate level of host acceptance, which did not differ between reciprocal crosses. Alleles promoting greater oviposition on lentil thus were inherited additively, with no evidence of sex-linkage or cytoplasmic effects. In a time-course study, hybrid females initially resembled the parent from the mung-bean line, as few eggs were laid on lentil during the first 24 h. However, oviposition rates on lentil after 72 h were closer to the rate observed in the lentil-line parent. Inferences about additivity vs. dominance in genes affecting oviposition may, therefore, depend on experimental protocol. Comparison with earlier work suggests that inheritance patterns observed in crosses between recently derived selection lines (as in this study) may differ from those obtained in crosses between long-divergent geographic populations.

Lentil is recognised as the most nutritious rabi pulse and, with respect to acreage, it ranks next to chickpea. It is grown throughout northern and central India. A large percentage of Indians are vegetarian and lentil has long been part of India's indigenous diet, and is a common source of protein. Of about 60 varieties released in India to date, 13 have been developed by hybridization, mostly from parents not distantly related. The narrow genetic base of the presently cultivated varieties and losses due to biotic and abiotic stress factors remain the main cause of concern. Introgression of genes between microsperma and macrosperma groups of lentil from closely related species like L. culinaris subspp. Orientalis and use of biotechnological tools, wherever necessary, have been recommended by various workers to broaden the genetic base of this crop. Direct selection for grain yield through important component traits such as pods/plant, seeds/pod, number of clusters/plant, harvest index, biological yield, early maturing and breeding for better yield quality have been suggested. Realizing the significance of plant germplasm, special efforts have been made by the national bureau to collect the genetic resources of lentil from different states of India. A large number of accessions were characterised and evaluated for various agro-morphological traits, using the lentil minimal descriptor. The core collection comprising 287 promising accessions recorded variation for seed yield and its important component traits; variation was also observed for important morphological traits, using mutation breeding approaches. These genetic resources of lentil have also been screened for tolerance to several biotic stresses and a few lines showed immunity against rust, blight and fusarium wilt and these have been utilized as donors in cross-breeding programmes. On the other hand, wild Lens species revealed substantial genetic diversity for phenological and agro-morphological characters, including some important diseases of lentil. From these genetic resources, potential donors of desirable traits have been selected after evaluation and characterization and have been utilized in the genetic improvement of cultivars.

On the premise that seed ageing may be largely a result of free-radical lipid autoxidation, a study was made of the relationship between lipid stability and longevity in seeds of soybean (Glycine max), lentil (Lens culinaris), mungbean (Vigna radiata), chickpea (Cicer arietinum), broadbean (Vicia faba), pea (Pisum sativum), lettuce (Lactuca sativa), and tomato (Lycopersicon esculentum). Seed lipids were examined for α-, γ- and δ-tocopherols, and levels of unsaturated and saturated fatty acids. Using this information, analysis was attempted using linear, multiplicative or exponential models to correlate aspects of lipid stability with seed longevity values from the published literature. No statistically significant correlations could be found between longevity and total lipid unsaturation, tocopherol levels or two protection formulae obtained from the oil chemistry literature. When values for tomato were excluded, a good correlation (r = 0.89, P = 0.007) was obtained using a multiplicative regression model for levels of linolenic acid per unit of total tocopherols in relation to longevity. Possible factors contributing to a lessening of the relationship between lipid stability and seed longevity are discussed.

The International Center for Agricultural Research in the Dry Areas (ICARDA) is participating in a large-scale programme, Subprogram 1 of the Consultative Group on International Agricultural Research (CGIAR) Generation Challenge Program, that aims to explore the genetic diversity of the global germplasm collections held by the CGIAR research centres. This project will identify a ‘composite collection’ of germplasm for individual crops, representing the range of diversity of each crop species and its wild relatives, and characterize each composite set using anonymous molecular markers, mainly simple sequence repeats (SSRs). The overall goal of this project is to study diversity across given genera and identify genes for resistance to biotic and abiotic stresses that can be used in crop improvement programmes. ICARDA was responsible for creating the composite collection for lentil. ICARDA has the global mandate for lentil and houses the largest global collection of this crop with 10,509 accessions. From this collection, a global composite collection of 1000 lentil accessions was established with the aim to represent genetic diversity and the agro-climatological range of lentil. Accessions for the composite collection were compiled from landraces, wild relatives, and elite germplasm and cultivars. The methodology presented here combined classical hierarchical cluster analyses using agronomic traits and two-step cluster analyses using agro-climatological data linked to the geographical coordinates of the accessions' collection sites. Genotyping for 30 SSR loci will be carried out for all 1000 accessions. Plants grown for DNA analysis will be harvested and progeny will be evaluated under field conditions at ICARDA.

Glasshouse studies were conducted to determine mechanisms of resistance of five genotypes of lentil Lens culinaris (Medikus) previously identified as resistant and moderately resistant to the pea aphid Acyrthosiphon pisum (Harris). A susceptible standard, ILL 8127, was also included. French Indigo had high levels of antibiosis, demonstrated by reduced reproductive period, fecundity and longevity, while Spanish Brown had high levels of antixenotic and tolerance components of resistance. Based on overall resistance, French Indigo was the most resistant genotype followed by Spanish Brown. These genotypes could be a source for resistance to A. pisum. All five genotypes had varying levels of antibiosis, antixenosis and tolerance components of resistance compared with ILL 8127.

Disease resistance, increased crop residues and altered plant and canopy design are the primary strategies being used to solve the major problems of cool season food legumes that are an integral component of cropping systems in the rainfed areas of the U.S. Pacific Northwest. Dry pea, seed pea and lentil predominate among these legumes, but there is increasing interest in chickpea. Several diseases are major hazards to production, including root rots, wilts, powdery mildew, Ascochyta blight, and viruses. Pea and lentil cultivan resistant to root rots, wilts, and powdery mildew are being developed and released. Progress is being made on resistance to v iruses transmitted by aphids, including pea enation mosaic and bean leaf roll. Development of res istant cultivars has been the principal control strategy for several diseases: Ascochyta blight of chickpea and lentil; root rots and wilts of pea, lentil, and chickpea; powdery mildew of pea; and viruses of pea and lentil. Chickpea cultivars resistant to Ascochyta blight were recently made avallable to producers. Another problem is that crop residues are insufficient to control erosion. Research is underway on genetically increasing biomass and residue production in lentil and dry pea and on producing more lignified stems and other plant parts that are more resistant to breakdown during harvesting and subsequent tillage. Increased biomass also might increase grain yields and red uce harvesting losses. The semi-leafless and woody stem traits in pea, the bushy plant types of lentil and chickpea, and diverse pod traits in all the legumes have shown promise for increased yield potential, ease of harvest, and reduced shattering losses.