Lens Culinaris Medik Research Articles

Identification of Sicilian landraces and Canadian cultivars of lentil using an image analysis system

Seed colour and size determine the appearance of grain legumes such as lentils (Lens culinaris Medik.). Currently, these characteristics are assessed by visual inspection of grain; it is slow and subjective, for this reason an objective imaging system was developed in Canada to measure bulk seeds lentil colour and size in a consistent manner for lentil quality colour grading. The Canadian imaging method, using image captured by a flatbed scanner, was modified in collaboration with the Stazione Sperimentale di Granicoltura (Research Institute in Sicily) to measure seed size, shape and mean colour on individual seeds; each seed imaging data were computed with a Linear Discriminant Analysis (Classifier) to identify five Sicilian landraces of Lens culinaris Medik., precisely Aragona, Bronte, Leonforte, Ustica and Villalba and three common Canadian accessions, cv Laird, cv Crimson and cv Eston. The performance of the classifier was 99.8% for the training sets and 97.1% for the independent test set. In addition to commercial international trade, lentil seed characterisation is very important to identify and catalogue in a biodiversity conservation program.

Chickpea, lentil and pea response to delayed spring seeding on the Northern Great Plains

We compared the effects of spring seeding date on stand density, crop growth, seed yield, water-use-efficiency, and grain quality of three pulse crops [chickpea (Cicer arietinum L.), lentil (Lens culinaris Medik.) and pea (Pisum sativum L.)] grown at Scott and Swift Current, SK, during 1993 to 1997. Wheat (Triticum aestivum L. emend. Thell.) was used as a reference crop. Seeding date did not meaningfully affect plant density for chickpea, lentil or pea. Crop growth stage related to thermal time resulted in robust prediction equations for chickpea, lentil and pea (R2 = 0.87 to 0.98). When seeding was delayed 2 wk, the crop response was inconsistent. When seeding was delayed by 4 wk, consistent, mainly negative, effects on crop parameters occurred due to the exacerbation of summer drought stress. Pulse crop yields were more negatively affected by delayed seeding than were wheat yields. When seeding of chickpea, lentil, and pea was delayed 4 wk, seed yield decreased at the majority of site-years. When yield reductions occurred, the average reductions were 44, 38, and 31%, for the respective species. For chickpea and lentil, seeding delays of 2 and 4 wk decreased seed size at the majority of site-years with seed size reductions averaging 10% when they occurred. In the semiarid Northern Great Plains (NGP), chickpea, lentil, and pea should be seeded before spring wheat due to a greater risk of loss of yield and quality. Key words: Chickpea, growth stage, lentil, northern great plains, pea, seeding date

Red-Green-Blue (RGB) colour density as a non-destructive marker in sorting deteriorated lentil (Lens culinaris Medik.) seeds

Red-Green-Blue (RGB) colour density as a non-destructive marker in sorting deteriorated lentil (Lens culinaris Medik.) seeds

Pollen and pistil morphology, in vitro pollen grain germination and crossing success of Lens cultivars and species

Morphological and in vitro germination characteristics of pollen altogether with pistil and style length were analysed, so as to carry out a morphological comparison between different lentil (Lens culinaris Medik.) cultivars and wild species, as well as to correlate the morphological and functional statistics with data regarding crossing success. Pollen length and width in the different genotypes were found to have a positive and highly significant correlation with pistil and style length and in vitro pollen tube length. A cluster analysis detected two different plant groups, namely, (i) large-seeded L. culinaris (macrosperma), and (ii) a second group formed by two subgroups, a first subgroup with L. ervoides standing alone and a second subgroup including small-seeded L. culinaris (microsperma) and the wild L. culinaris ssp. orientalis, L. odemensis, L. nigricans. A high and significant correlation was detected between crossing success and phenotypic similarity (r > 0.98; P < 0.05), therefore implying that phenotypic similarity, based on pollen morphology and in vitro pollen length together with pistil and style length, is a good predictor of hybridization success.

Effect of Accelerated Ageing on Germination and Vigor in Lentil (Lens culinaris Medikus) Seed

ABSTRACT Seed lots of three lentil (Lens culinaris) cultivars (ILL 5883, ILL 7012 and Precoz), with similar production and storage history were aged for 1, 2 or 3 days at 40 ± 0.5°C and 100% relative humidity (RH). The effects of ageing were evaluated via standard germination tests, speed of germination, seedling dry weight, and vigor index. Of the three cultivars, ILL 5883 and Precoz retained their viability better than ILL 7012 after 1 day of ageing. ILL 5883 appeared to be the most tolerant of ageing conditions and its performance was consistently superior to that of the other two cultivars. The three-day ageing treatment severely damaged all seeds and led to a significant reduction in germination percentage in both ILL 7012 (1%) and Precoz (5%). Ageing for three days also significantly reduced vigor in ILL 7012: Values for indices of both speed of germination and vigor were 0.6 and 11.25 as opposed to 12.5 and 1439.61 in unaged seeds, respectively. In general, an increase in the duration of accelerate...

First Report of Damping-Off of Canola Caused by Rhizoctonia solani AG 2-1 in Washington State.

In early September 2003, winter canola (Brassica napus L) cv. Inca was direct seeded into plots previously cropped with spring barley at the Washington State University Dryland Research Station at Lind, WA. Before planting, the plots received 80 mm of water by sprinkler irrigation, and 2 weeks later, volunteer barley was killed with Paraquat contact herbicide. In late September, 3 weeks after planting, canola seedlings exhibited postemergence damping-off and lesions on the hypocotyls, resulting in significant stand reductions. Rhizoctonia solani was isolated from infected hypocotyls using water agar amended with chloramphenicol (100 μg/ml). Cultures on potato dextrose agar produced dark brown colonies with dark brown microsclerotia. Three isolates were grown on autoclaved oat seed for 3 weeks in 1-liter Erlenmeyer flasks at 22°C, and colonized seed was air dried in a laminar flow hood, ground in a coffee grinder, and added to a Thatuna silt loam at 1% (w/w). The infested soil was placed into 4- × 20.5-cm plastic tubes and planted with five canola seeds per tube, five tubes per isolate. In the control treatment, soil was not infested. Plants were grown in a temperature-controlled room in a greenhouse at 16°C, 12-h light/dark. Isolates caused pre- and postemergence damping-off after 1 week, and the surviving seedlings had significantly less plant height and dry weight. Isolates were identified as AG 2-1 by pairing cultures with AG 8, 2-1, and 10 on agar-coated slides (1). Selected isolates were also identified as AG 2-1 by sequencing of the ITS 1 and 2 regions of the rDNA and matching them to sequences in GenBank. On a farm north of Pullman, WA in 2004, R. solani was isolated from soil in spring and winter wheat fields using a toothpick baiting method (2). R. solani was found primarily from sites previously cropped with winter and spring canola. These isolates were identified as AG 2-1 and five isolates were tested in the greenhouse, as described above, on canola (cv. Inca), lentil (Lens culinaris Medik. cv. Merrit), wheat (Triticum aestivum L. cv. Madsen), barley (Hordeum vulgare L. cv. Baronesse), pea (Pisum sativum L. cv. Stirling), and chickpea (Cicer arietinum L. cv. Sierra). Three of five isolates significantly reduced emergence of canola, and all isolates significantly reduced dry weight of canola seedlings and caused lesions on hypocotyls. None of the isolates reduced emergence of the other crops. All isolates reduced the dry weight of pea and three isolates reduced plant height. None of the isolates reduced the dry weight of lentil, chickpea, wheat, or barley. One of the isolates was also tested on Arabidopsis thaliana and found to be pathogenic. R. solani AG 2-1 has been reported as an important pathogen on canola in Canada and Australia, but has not been reported from the Pacific Northwest of the United States. R. solani AG 2-1 is also pathogenic on rapeseed, mustard, and subterranean clover and has been isolated from wheat, sugar beets, and potato (3). Canola is a minor rotation crop in cereal-based cropping systems in eastern Washington (1,600 ha in 2005), but there is increasing interest in this oilseed crop for biodiesel production. However, R. solani AG 2-1 may reduce stands and yield of canola.

Stability of performance in lentil (Lens culinaris Medik) genotypes in Iran

Summary The development of genotypes, which can be adapted to a wide range of diversified environment, is the ultimate goal of plant breeders in a crop improvement program. In this study, several stability methods were used to evaluate the genotype by environment interaction (GE) in 11 lentil (Lens culinaris Medik) genotypes. The genotypes were evaluated for grain yield at 4 different locations for 3 years in semi arid areas of Iran. The testing locations have different climatic and edaphic conditions providing the conditions necessary for the assessment of stability. A combined analysis of variance, stability statistics, rank correlations among stability statistics and yield stability statistic were determined. Significant differences were detected between genotypes and their GE interactions. Different univariate stability parameters were used to determine stability of the studied genotypes. The level of association among the parameters was assessed using Spearman’s rank correlation. The different stability statistics which measured the different aspects of stability was substantiated by rank correlation coefficient. Rank-correlation coefficients between yield and some stability parameters were highly significant. Genotypes mean yield (Mean) was significantly correlated to the Lin and Binns stability parameter PI (r = 0.93 ∗∗ ) and desirability index Di (r = 0.89 ∗∗ ). A principal component analysis based on rank correlation matrix was performed for grouping the different stability parameters studied. In conclusion, based on most stability parameters, the genotypes G2, G5 and G9 were found to be the most stable. Results from rank correlation and principal component analysis showed that the stability variance (σ 2 i ) was strongly correlated with Wricke’s ecovalance, stability parameters of Plaisted and Peterson, and Plaisted.

CDC Redberry lentil

CDC Redberry is a high-yielding, red cotyledon lentil (Lens culinaris Medik.) cultivar developed by the Crop Development Centre, University of Saskatchewan, Saskatoon, Saskatchewan. It has gray seed coat colour, suitable for the red market class of lentil. It is intended for cultivation in all lentil growing areas of western Canada. CDC Redberry was issued registration No.5771 on 2003 Dec. 19 by the Variety Section, Plant Products Division, Canadian Food Inspection Agency. Key words: Lentil, cultivar description, Lens culinaris

Nonparametric Methods for Interpreting Genotype × Environment Interaction of Lentil Genotypes

ABSTRACTAnalysis of multienvironment trials (METs) of crops for cultivar evaluation and recommendation is an important issue in plant breeding research. Evaluating both stability of performance and high yield is essential in MET analyses. The objective of this investigation was to compare 10 nonparametric stability methods and apply nonparametric tests (which do not require distributional assumptions) for genotype‐by‐environment (G × E) interaction to 11 lentil (Lens culinaris Medik) genotypes. Nine improved lentil genotypes and two local cultivars were grown in 20 semiarid environments in Iran from 2002 to 2004. Results of nonparametric tests of G × E interaction and a combined ANOVA across environments showed there were both crossover and noncrossover G × E interactions and genotypes varied significantly for yield. In this study, high values of TOP (proportion of environments in which a genotype ranked in the top third) and low values of rank‐sum (sum of ranks of mean yield and Shukla's stability variance) were associated with high mean yield, but the other nonparametric methods were not positively correlated with mean yield and instead characterized a static concept of stability. The results of principal component (PC) analysis and correlation analysis of nonparametric stability statistics and yield indicated that only rank‐sum and TOP methods would be useful for simultaneously selecting for high yield and stability. These methods recommended FLIP 92–12L as stable and FLIP96–6L as unstable genotypes. A biplot of the first two PCs also revealed that the nonparametric methods grouped as three distinct classes that corresponded to different agronomic and biological concepts of stability.

Microbial Biomass Turnover in Indian Subtropical Soils under Different Sugarcane Intercropping Systems

Changes in soil organic C (Corg), total N (Nt), available nutrients, soil microbial biomass C (Cmic) and N (Nmic), and mineralizable C and N in the sugarcane (Saccharum officinarum L.) rhizosphere were evaluated under intensive sugarcane cropping systems with intercrops including wheat (Triticum aestivum L.), maize (Zea mays L.), rajmash (Phaseolus vulgaris L.), green gram [Vigna radiata (L.) R. Wilczek var. radiata], cowpea [Vign aunguiculata (L.) Walp.], lentil (Lens culinaris Medik.), mustard (Brassica rapa L.), potato (Solanum tuberosum L.), and sesbania (Sesbania rostrata Bremek. &amp; Oberm.) in subtropical soils of India. Organic C increased significantly when maize (25%), wheat (24%), mustard (19%), potato (17%), and rajmash (13%) were intercropped with sugarcane, while legume intercrops substantially increased Nt and available N. Increase in microbial respiration was greater where maize (42%), wheat (37%), or mustard (31%) were intercropped compared with pulse crops. Soil microbial biomass C accounted for 2.7 to 3.3% of Corg content and Nmic accounted for 2.6 to 3.7% of Nt under different intercropping conditions. A higher CO2 evolution rate and wider Cmic/Nmic ratios were recorded with cereal and mustard intercrops, whereas higher N mineralization was recorded with pulse intercrops. Results indicate that intercropping with pulse crops and incorporation of their labile C substrate improved N mineralization. The build up of the C pool and Cmic in the case of cereals, mustard, and potato intercropping should promote long‐term stability.

Tempo‐spatial covariance structure of lentil yield and water use efficiency from supplemental irrigation trials

AbstractIn agricultural research conducted in dry areas, crop‐yield water use efficiency (WUE) is a measure used to evaluate the impacts of various agronomic factors on crop productivity. Agronomic management factors include supplemental irrigation (SI) and crop‐rotation systems, which are used to increase the sustainability of crop production systems. A study of lentil (Lens culinaris Medikus) was conducted in split‐plot experiments in randomized complete blocks, where planning date (PD) were assigned to main‐plots and SI to sub‐plots. Lentil was grown in rotation with durum wheat (i.e., lentil was grown 1 year and durum wheat the next, on the same plot of land) over a period of 4 years (1996/1997–1999/2000) at the research station of the International Center for Agricultural Research in the Dry Areas (ICARDA), at Tel Hadya, Syria. Spatial variability in the field trials and correlations between the plot errors arising over time were studied to examine their effects on the significance and precision of the estimates of the effects of PD and SI on yields (of both seed and total biomass) and WUE. The analyses revealed the presence of significant linear soil‐fertility trends within the fields and strongly auto‐correlated plot errors. When these trends were accounted for in the analysis of yield and WUE data, the estimates of the treatment effects had greater levels of significance and precision than when the trends were ignored. It is recommended that in agronomic field trials, such as lentil variety evaluation trials, one should identify the most appropriate spatial and temporal covariance structures and use these to draw statistical inferences about the effects of agronomic input factors. Copyright © 2006 John Wiley &amp; Sons, Ltd.

Zinc is critically required for pollen function and fertilisation in lentil

The role of zinc (Zn) in reproduction of lentil ( Lens culinaris Medik. cv. DPL 15) and the extent to which the Zn requirement for reproduction can be met through supplementation of Zn at the time of initiation of the reproductive phase have been investigated. Low supply (0.1 μmol/L) of Zn reduced the size of anthers, the pollen producing capacity and the size and viability of the pollen grains. Scanning electron microscopy (SEM) of pollen grains of Zn deficient plants showed enhanced thickening of exine and wide and raised muri. In vitro germination of pollen grains was reduced by >50% and growth of pollen tubes was retarded. Unlike Zn sufficient plants, the cuticle around the stigmatic papillae of Zn deficient plants remained intact, preventing the interaction between pollen grains and stigmatic exudates that provides the polarity for the growth of pollen tubes through the stylar tract. Zn deficiency increased the activity of acid phosphatase and peroxidase in extracts of pollen grains. Histochemical localisation on the stigmatic surface and native PAGE of the enzyme extracts of pollen grain and stigma exudates showed enhanced expression of acid phosphatase and peroxidase and suppressed expression of esterase in response to Zn deficiency. Zn deficiency reduced the setting of seeds and also their viability. The effect on seed setting was more marked than on in vitro germination of pollen grains, suggesting that the latter was not the exclusive cause of inhibition of fertility. Possibly, loss of fertility was also caused by impairment in pollen–pistil interaction conducive to pollen tube growth and fertilisation. Impairment in pollen structure and function and seed setting was observed even when plants were deprived of Zn at the time of flowering, but to a lesser extent than in plants maintained with low Zn supply from the beginning. Increasing the Zn supply from deficient to sufficient at the initiation of flowering decreased the severity of Zn deficiency effects on pollen and stigma morphology, pollen fertility and seed yield. In conclusion, structural and functional changes induced in pollen grains and stigma of Zn deficient plants and associated decrease in seed setting of lentil indicate a critical requirement of Zn for pollen function and fertilisation that can be partially met by supplementing Zn at the onset of the reproductive phase.

Aeration is more important than shoot orientation when rooting lentil (Lens culinaris Medik.) cv. ‘Digger” microcuttings in vitro

Rooting in vitro was examined for lentil nodal segments to test a recently published conclusion that shoot orientation has an effect on rooting. As is the case for many species, roots initiated and grew only at the proximal end of the microcutting regardless of its orientation. When the proximal end was in agar (a hypoxic environment) the rooting percentage was low (9–25%) even when the orientation of the microcutting was altered by inventing the culture tube. In contrast, when the proximal end of the microcutting was in an aerobic environment (from the shoot being placed upside down in agar medium or placed normally or upside down in an aerated medium), rooting percentages were higher (62–100%). Medium aeration at the proximal end of the microcutting is more important than shoot orientation for in vitro rooting of lentil microcuttings.

Recent progress in the ancient lentil

Lentil (Lens culinaris Medikus subsp. culinaris) was among the first crops domesticated and has become an important food legume crop in the farming and food systems of many countries globally. Its seed is a rich source of protein, minerals, and vitamins for human nutrition, and the straw is a valued animal feed. Its ability in nitrogen and carbon sequestration improves soil nutrient status, which in turn provides sustainability in production systems. In the current paper, research progress achieved in lentil improvement at national and international levels is reviewed.Since the late 1970s there have been significant national and international lentil improvement programmes, with the main objectives being to develop phenologically adapted, stress resistant and high-yielding cultivars with improved production packages.Systematic research on lentil started recently, compared to other early-domesticated crops. During the last two and a half decades, research progress has been made in various aspects of the crop. Large numbers of germplasm have been collected, evaluated and preserved at national and international levels, with the International Center for Agricultural Research in the Dry Areas (ICARDA) holding the largest collection of cultivated and wild germplasm accessions. A major effort has been made to study the genetic variation in the world germplasm collection, in order to understand local adaptation and to develop specific research programmes. Genotypes with resistance to various biotic and abiotic stresses, particularly resistance to vascular wilt, rust and Ascochyta blight have been identified, and directly exploited or used in breeding programmes. New genotypes have been bred with good standing ability, suitable for mechanical harvest for West Asia and North Africa. Through introduction and hybridization, the genetic base of lentil has been broadened, most particularly in South Asia, by breaking an ancient genetic bottleneck.Agronomic practices, including seeding time, seed rate, tillage requirements, soil type, and weed control, are optimized locally and improved production packages have been developed to realize higher yield. To date, a total of 91 improved cultivars have been released globally, emanating from genetic material supplied by ICARDA. Due to adoption of improved varieties combined with production technologies, the average global productivity has increased from 611 kg/ha to 966 kg/ha, and total production from 1·3 million tonnes to 3·8 million tonnes in the last three decades. Research at the molecular level, including construction of a lentil genetic linkage map, identification of molecular markers, and genetic transformation, has progressed considerably.

Differences in syntenic complexity between Medicago truncatula with Lens culinaris and Lupinus albus

Orthologous markers transferable between distantly related legume species allow for the rapid generation of genetic maps in species where there is little pre-existing genomic or EST information. We are using the model legume Medicago truncatula Gaertn. to develop such markers in legumes of importance to Australian agriculture. This will enable the construction of comparative genetic maps, help to determine patterns of chromosomal evolution in the legume family, and characterise syntenic relationships between M. truncatula and cultivated legumes. This information can then be used to identify markers that are tightly linked to the genes of interest, candidate gene(s) for a trait, and expedite the isolation of such genes. Among the Papilionoideae, we compared ESTs from the phylogenetically distant species, M. truncatula, Lupinus albus and Glycine max, to produce 500 intron-targeted amplified polymorphic markers (ITAPs). In addition to 126 M. truncatula cross-species markers from Department of Plant Pathology, University of California (USA), these markers were used to generate comparative genetic maps of lentil (Lens culinaris Medik.) and white lupin (Lupinus albus Linn.). Our results showed that 90% of the ITAPs markers amplified genomic DNA in M. truncatula, 80% in Lupinus albus, and 70% in Lens culinaris. The comparative map of Lens culinaris was constructed based on 79 ITAP markers. The Lupinus albus comparative map was developed from 105 gene-based markers together with 223 AFLP markers. Although a direct and simple syntenic relationship was observed between M. truncatula and Lens culinaris genomes, there is evidence of moderate chromosomal rearrangement. This may account for the different chromosome numbers in the two species. A more complicated pattern among homologous blocks was apparent between the Lupinus albus and M. truncatula genomes.

A water deficit during pod development in lentils reduces flower and pod numbers but not seed size

An experiment was conducted under controlled conditions in a glasshouse to determine the sensitivity of reproductive development of lentil (Lens culinaris Medikus) genotypes of different origins to water deficit. The 3 genotypes were Cassab (West Asia), Simal (South Asia), and ILL 7979 a crossbred between a West Asian genotype and a South Asian genotype. Two watering treatments, a well-watered control and a water-deficit treatment, were imposed from the beginning of podding. Leaf water relations, total dry matter production, leaf area, and number of flowers, pods, and seeds were measured from podding to maturity. In the well-watered plants the leaf water potential (ψleaf) before sunrise ranged from −0.6 to −0.8 MPa. When subjected to water deficit, ψleaf fell to about −3.0 MPa. Genotypes did not show variation in vegetative growth or seed yield under either well-watered or water-deficit conditions, but they differed significantly in the number of flowers, fruiting nodes, pods, and seeds, and harvest index (HI). Seed size in Cassab was 61% larger than ILL 7979 and 105% larger than Simal. The small-seeded genotypes produced the highest number of fruiting nodes and hence a greater number of flowers, pods, and seeds. Seed size was positively correlated with seed growth rate (r = 0.77**) and seed fill duration (r = 0.45*). The water deficit reduced plant height by about 20%, leaf area by 48–81%, and total dry matter by about 60% compared with well-watered plants. The water deficit reduced flower number by 35–46% and increased seed abortion (empty pods) by 17–46%. The water deficit had no effect on the maximum seed growth rate, seed fill duration, or final seed size in any of the 3 genotypes. Therefore, the 70% reduction in seed yield induced by the water deficit was primarily due to a reduction in pod and seed numbers (by 59–70%) rather than individual seed growth rate and seed size.

Physiological and seed yield responses to water deficits among lentil genotypes from diverse origins

The effect of water deficits at 2 growth stages on the physiology and growth of lentil (Lens culinaris Medikus subsp. culinaris) genotypes bred/selected for 3 regions was examined in a glasshouse experiment. The water regimes imposed were: (i) a well-watered control, (ii) water withheld at flowering, from 72 to 93 days after sowing (DAS), and (iii) water withheld from podding (93 DAS) to maturity. The genotypes were a West Asian genotype released in Australia (Cassab), 2 South Asian Nepali cultivars (Khajura 2 and Simal), and 3 crossbreds between West Asian and South Asian parents (ILL 6829, ILL 7979, and ILL 7982). ILL 7979 and Simal had significantly greater total dry matter, water use, seed yield, number of pods and seeds per plant, and harvest index (HI) than the other genotypes under well-watered conditions. Water deficits reduced seed yield by up to 60% in the crossbreds and the South Asian cultivar, Simal. However, seed yield was increased by the water deficit at flowering and the water deficit at podding in the West Asian genotype, Cassab, and the South Asian genotype, Khajura 2, respectively. In the other genotypes, withholding water at flowering or podding reduced leaf area (48–55%), total dry matter (32–50%), flower production (22–55%), and number of pods and seeds (27–66%), with significantly higher flower drop and empty pods when water was withheld. The higher seed yield in Cassab and Khajura 2 when water was withheld was related to the production of more flowers and the maintenance of pod and seed set when they were re-watered after the period of water deficit. When water was withheld during flowering, the West Asian genotype Cassab and the crossbred ILL 6829 used less water and hence maintained a high leaf water potential (ψleaf), whereas ψleaf decreased earlier to lower values in the crossbred ILL 7979 and the South Asian genotypes Khajura 2 and Simal. There were no significant differences in leaf net photosynthesis (PN), or stomatal conductance (gS), among genotypes during flowering and early podding, but PN and gS were reduced by 22–38 and 19–67%, respectively, when water was withheld. The lower ψleaf in ILL 7979, Simal, and Khajura 2 induced greater osmotic adjustment (OA) during the drying cycle at flowering, whereas there was no or little OA when water was withheld at podding. Variation in physiological traits (PN, gS, OA) under both watering regimes was not directly related to seed yield, but seed number was related to seed yield under both well-watered and water-deficit conditions.

Residue cover in wheat systems following dry pea and lentil in the Palouse region of Idaho

Crop management practices are needed that increase crop residue groundcover and reduce soil erosion after winter wheat ( Triticum aestivum L.) planting in the Palouse region of northern Idaho and eastern Washington. Trials were conducted in 1997 and 1998 at the University of Idaho Kambitsch Research Farm near Genesee, Idaho, using farm scale equipment to evaluate dry pea ( Pisum sativum L. subsp. sativum) and lentil ( Lens culinaris Medik) residue production and groundcover across cultivars and tillage intensity. After harvest, legume plot areas were prepared for winter wheat seeding using four main plot tillage systems designed to give progressive levels of tillage intensity: no-till (NT), Ripper–Shooter™ (RS), RS plus one cultivation, and RS plus two cultivations. In 1997, the two dry pea cultivars produced significantly greater residue than the lentil cultivars. In 1998, ‘Pro 2100’ dry pea had significantly higher residue production than ‘Columbian’ pea and ‘Crimson’ lentil cultivars. In 1997, initial residue cover was highest with NT, averaging 74% groundcover across legume cultivars. After winter wheat seeding, residue cover declined for all tillage treatments, but was still highest at 40% residue cover under NT. In 1998, residue cover was lower for all tillage treatments across all cultivars than in 1997, but NT still had the highest initial residue cover. Wheat yield was not affected by tillage or previous crop treatments in either year. This study showed that NT and reduced tillage systems can maintain previous crop residue on the surface for soil conservation and subsequent crop yields.

Sources of Resistance to Anthracnose (Colletotrichum truncatum) in Wild Lens Species

Lentil anthracnose (Colletotrichum truncatum (Schwein.) Andrus et W.D. Moore is a potential threat in many lentil (Lens culinaris Medik.) production regions of North America. In the lentil germplasm maintained in Germany and North America, 16 lines were reported to have resistance to race Ct1, but none has resistance reported to race Ct0. The objective of this study was to examine accessions of wild Lens species for their resistance to races Ct1 and Ct0 of lentil anthracnose. Five hundred and seventy-four wild accessions of six species and control lines were screened in two replications under both field and greenhouse conditions using a 1–9 scoring scale (1, highly resistant; 2–3, resistant; 4–5, moderately resistant; 6–7, susceptible; and 8–9, highly susceptible). Indianhead and PI 320937 were resistant while Eston and Pardina were susceptible to race Ct1 as expected. However, none of the check lines were resistant to race Ct0. Among the six Lens wild species tested, accessions of Lens ervoides (Brign.) Grande had the highest level of resistance, 3–5 to race Ct1 and Ct0 followed by L. lamottei Czefr. in the field and greenhouse. Lens orientalis (Boiss.), L. odemensis L., L. nigricans (M. Bieb.) Godron and L. tomentosus L. were highly susceptible, 8–9 to race Ct0 in the greenhouse. The highest frequency of resistance, especially in L. ervoides (Brign.) Grande, was found in accessions originating from Syria and Turkey. The usefulness of these L. ervoides (Brign.) Grande accessions as sources of resistance to the more virulent race of anthracnose in a lentil breeding program is discussed.

Response of lentil to microbial inoculation and low rates of fertilization in the semiarid Canadian prairies

The use of microbial inoculation may increase nodulation and seed yield of annual legumes. A study was conducted to determine the effect of formulations (seedapplied powder vs. soil-applied granular inoculants), placement of granular inoculants in soils (applied in the seed-row vs. sidebanded), and low rates of fertilizers in comparison to P-solubilizing microbes Penicillium bilaii on plant establishment, maturity, and seed yield of lentil (Lens culinaris Medik.) in the semiarid Canadian prairies. Green lentil was grown on a silt loam and a heavy clay soil in southwestern Saskatchewan from 1999 to 2002. Inoculated lentil with Rhizobium increased seed yield by 45% averaged across all 6 site-years. Granular soil inoculants increased lentil seed yield by 19% over seed-applied inoculants. Placement of soil inoculants in the seed row or side-bands produced similar results. On the silt loam soil, the use of rhizobial inoculants increased lentil seed yield by 15%, while the yield increase was 70% on the heavy clay. Starter N applied at a rate of 15 kg ha-1 increased seed yield by 13% for lentil grown on the heavy clay, but there was no effect on the silt loam. Phosphorus fertilizer applied at a rate 15 kg P ha-1 did not influence lentil establishment, growth or seed yield. Similarly, the P-solubilizing microbes P. bilaii did not influence plant growth or development, nor did it affect the seed yield of lentil. Soil granular rhizobial inoculants are preferred over seed-applied inoculants, fertilizers, or P-solubilizing microbes in lentil because of their strong and consistently positive impact on plant growth and seed yield in the semiarid Canadian prairies. Key words: Lens culinaris, nodulation, seed yield, Penicillium bilaii, P-solubilizing microbes