Asian Journal of Research in Crop Science

Price Support for Oilseeds in India: An Analysis of Minimum Support Price Trends and Growth

2026-09-04T09:41:23+00:00

Minimum Support Price (MSP) has long served as a key instrument of India’s agricultural price policy, particularly in the oilseed sector, which plays a vital role in ensuring the country’s edible oil security. However, despite sustained policy efforts, India remains substantially reliant on imports of edible oils, highlighting the need to evaluate the effectiveness and consistency of MSP in promoting domestic oilseed production. In this context, the present study analyses the trends and dynamics of MSP for major oilseeds and copra in India during the period 2014–15 to 2024–25. The study aims to examine changes in MSP over time, assess year-on-year and long-term growth patterns, and formulate appropriate policy recommendations for improving price support mechanisms in the oilseed sector. A descriptive and analytical research design was adopted using secondary data sourced from the Commission for Agricultural Costs and Prices (CACP), Government of India. Year-on-year growth rates and compound annual growth rates (CAGR) were employed to evaluate the growth and variability of MSP. The results indicate a steady increase in MSP for all oilseed crops, with comparatively higher growth observed in minor oilseeds and coconut products. In terms of CAGR, nigerseed (9.25%), ball copra (8.11%), milling copra (7.83%), and sesamum (7.26%) recorded greater long-term growth in MSP than major oilseeds such as groundnut and soybean. The findings emphasise the importance of developing a more stable, predictable, crop-specific, and procurement-oriented MSP framework to strengthen farmers’ confidence and encourage oilseed production. Effective implementation of MSP, supported by complementary policy measures, can help reduce India’s dependence on edible oil imports and promote sustainable development of the domestic oilseed sector.

Incidence and Damage of Bruchid Infestation on Selected Common Bean Varieties under Farmers’ Storage Conditions in Burundi

2026-09-19T13:07:30+00:00

Common bean (Phaseolus vulgaris L.) is a vital legume crop globally, providing essential proteins and micronutrients, particularly in developing countries. In Burundi, beans are integral to food security and rural livelihoods, yet smallholder storage practices expose seeds to significant postharvest losses, primarily from the bruchid pests Acanthoscelides obtectus and Zabrotes subfasciatus. Despite the economic importance of beans, limited research has systematically evaluated varietal resistance patterns and storage dynamics under realistic smallholder conditions across different agro-ecological zones in Burundi. This study evaluated the effects of storage duration, environmental conditions, and varietal resistance on bruchid infestation across Burundi's three agroecological zones. Four common bean varieties (Kinure, Mukungugu, Musore, and Gasilida) were monitored monthly over four months (February-May 2025) across six sites in an experiment employing a completely randomised design, with 72 samples and three replications. Parameters measured included seed perforation, bruchid emergence and mortality, and seed weight under typical farmer storage conditions. Storage duration significantly influenced infestation dynamics (p < 0.001) for both bruchid species. Initial storage showed minimal damage (100% unperforated seeds), but deterioration accelerated from April onwards, with A. obtectus perforation reaching 3.75% and Z. subfasciatus perforation reaching 5.13% by May. Live bruchid populations peaked at 68.5% for A. obtectus in April and 94.21% for Z. subfasciatus in March. Significant varietal differences in emerged bruchids were observed (p < 0.001), with Kinure demonstrating superior resistance across all parameters. This variety maintained 99.42% unperforated seeds, the lowest perforation rate (0.58%), the highest seed weight (994.8 g), and the lowest live bruchid population (32.9%) for A. obtectus. Similar patterns occurred with Z. subfasciatus infestation. Conversely, Gasilida and Mukungugu showed greater susceptibility, with higher perforation rates and bruchid populations. Storage site effects were generally non-significant (p > 0.05), indicating that varietal characteristics were more influential than micro-environmental differences across altitudes ranging from 800 m to > 2000 m. The study identifies Kinure as a consistently resistant variety suitable for promoting storage pest management in regional seed systems. The findings validate genetic factors as primary determinants of seed storability and support variety-based approaches to reducing postharvest losses. The integration of resistant varieties with improved storage technologies offers promising pathways for enhancing food security in bean-dependent smallholder communities.

Impact of Farmer Field Schools Participation on the Adoption of Sustainable Agricultural Practices among Maize Farmers in Kamonyi District, Rwanda

2026-09-19T13:15:39+00:00

Farmer Field School (FFS) is a participatory extension approach widely used to strengthen smallholder farmers' knowledge and encourage the uptake of sustainable agricultural practices. This study assessed the impact of FFS participation on the adoption of sustainable agricultural practices among maize farmers in Runda and Rugalika sectors of Kamonyi District, Rwanda, over the period 2020–2024. A cross-sectional design combining quantitative and qualitative approaches was used. Data were collected through questionnaires administered to 301 maize farmers selected by systematic random sampling, complemented by key informant interviews with extension officers and community leaders. Quantitative data were analysed in SPSS using descriptive statistics, Pearson correlation, and multiple regression. Nearly all respondents (98.3%) had participated in FFS during the study period, with most attending sessions every season (80.7%) and participating for more than two years (86.4%). Participation was associated with strong self-reported knowledge gains, with 94.7% of farmers reporting improved understanding of sustainable maize farming practices. Adoption of the practices promoted through FFS was correspondingly high: soil erosion control measures reached moderate-to-full adoption among 88.3% of respondents, organic manure/compost use among 79.4%, and crop rotation and diversification among 77.7%. Pearson correlations showed statistically significant positive relationships (p < 0.05) between all FFS participation indicators and adoption outcomes, with frequency of attendance (r = 0.79) and knowledge increase (r = 0.81) most strongly associated with overall change in adoption. Multiple regression showed that duration in FFS, seasons participated, attendance frequency, and knowledge increase jointly explained 72.1% of the variance in adoption (R² = 0.721, Adjusted R² = 0.717, F(4,296) = 190.94, p < 0.001), with knowledge increase (β = 0.391) and attendance frequency (β = 0.344) being the strongest predictors. FFS participation was also associated with improved household income (96.3%) and food security (96.3%). Nonetheless, full adoption remained constrained by financial limitations, high input costs, limited land, inadequate irrigation, and restricted market access. These findings indicate that Farmer Field Schools can support farmers' knowledge development and sustainable practice adoption, and support their continued expansion alongside stronger financial and institutional backing to sustain climate-resilient maize production in Rwanda.

Optimising Organic Fertiliser Application to Enhance Photosynthetic Pigments and Physiological Performance in Moringa oleifera Seedlings

2026-09-22T11:24:49+00:00

In Malaysia, sustainable agricultural practices characterised by organic production systems are gaining increasing recognition because of their potential to reduce dependence on synthetic inputs. Moringa oleifera is a highly nutritious perennial species with well-documented medicinal and agro-ecological benefits. Chicken manure compost, characterised by its high nutrient content, gradual nutrient release and contribution to soil organic matter, has been recognised as an effective and environmentally sustainable fertiliser. This study evaluated the effect of chicken manure compost application on photosynthetic pigment composition in M. oleifera seedlings. The experiment was conducted using a randomised complete block design (RCBD) comprising four fertiliser rates (0, 100, 200 and 300 g plant⁻¹) with four replications. Under nursery conditions, photosynthetic pigment parameters were measured, including relative chlorophyll content, chlorophyll a, chlorophyll b, total chlorophyll and carotenoid concentration. Analysis of variance (ANOVA) indicated significant treatment effects (p < 0.05) for all pigment parameters, with particularly strong responses observed for total chlorophyll content and chlorophyll a (p < 0.01). Post hoc mean separation showed that fertiliser-treated plants consistently exhibited higher pigment concentrations than the unfertilised control, with increases of up to approximately 22% in relative chlorophyll content, 34% in chlorophyll a and 33% in total chlorophyll. Pigment accumulation increased markedly up to 200 g plant⁻¹, followed by stabilisation, indicating a saturating response rather than a continuous increase at higher application rates. Quadratic regression analysis further confirmed a positive but non-linear relationship between fertiliser application rate and pigment accumulation. These findings demonstrate that chicken manure compost enhances chlorophyll biosynthesis and carotenoid accumulation in M. oleifera seedlings, reflecting improved photosynthetic capacity and physiological vigour. Overall, this study highlights the effectiveness of organic nutrient inputs in promoting early seedling development and provides practical guidance for sustainable Moringa oleifera cultivation.

Effects of Chamber Types and Cultivar on the Performance of Plantain Macropropagation Technology (Musa paradisiaca L.)

2026-09-28T10:50:41+00:00

Plantain production is constrained by the limited availability of healthy, high-quality planting materials, making efficient and affordable propagation techniques important for sustainable production. Macropropagation provides a low-cost alternative to conventional sucker propagation and tissue culture; however, its performance may be influenced by the type of propagation chamber and cultivar. This study evaluated the effects of three macropropagation chamber types, namely wooden/nylon, bamboo/nylon and concrete chambers, and four plantain cultivars, namely Agbagba, Curare Enano, Obino Lewai and Orishele, on plantlet production and early plantlet development. The experiment was conducted at the Teaching and Research Farm, Ladoke Akintola University of Technology (LAUTECH), Ogbomoso, Oyo State, Nigeria, using a 3 × 4 factorial arrangement in a split-plot design with three replications. Data were collected on total number of plantlets produced, number of plantlets picked, survival rate and number of internodes. Chamber type significantly influenced plantlet production, plantlet pick, survival rate and number of internodes. The bamboo/nylon chamber recorded the highest mean plantlet production (7.68) and plantlet pick (2.62), followed by the wooden/nylon chamber (7.34 and 2.27), while the concrete chamber recorded the lowest values (5.10 and 1.49), respectively. The wooden/nylon chamber recorded the highest survival rate (82.39%), although this was statistically comparable with the bamboo/nylon chamber (79.62%), whereas the concrete chamber had the lowest survival rate (63.32%). Bamboo/nylon also recorded the highest number of internodes (2.33), followed by the wooden/nylon chamber (2.16), while concrete recorded the lowest (1.40). Cultivar did not significantly affect total plantlet production, survival rate or number of internodes, although Curare Enano recorded the highest numerical plantlet production (7.10), survival rate (78.40%) and internode number (2.03). Cultivar significantly affected plantlet pick, with Curare Enano recording the highest value (2.25) and Obino Lewai the lowest (1.94). The chamber × cultivar interaction was significant for plantlet production, with Obino Lewai producing the highest number of plantlets (8.63) under the bamboo/nylon chamber. The findings indicate that bamboo/nylon and wooden/nylon chambers provide more favourable conditions for low-cost plantain macropropagation than concrete chambers under the conditions of this study. Bamboo/nylon was particularly effective for plantlet production and internode development, whereas wooden/nylon chambers promoted superior plantlet survival. These chamber types may therefore be useful as affordable propagation structures for increasing the availability of clean, high-quality plantain planting materials.

Physiological Characterization in Some Groundnut Genotypes for Drought Tolerance

2026-09-28T13:05:30+00:00

Groundnut (Arachis hypogaea L.) is an important food and cash crop in Sudan, with approximately 70% of its production occurring under rainfed smallholder farming systems. However, productivity is severely constrained by recurrent drought, particularly during the reproductive stage. Identifying high-yielding and drought-tolerant genotypes adapted to local agro-ecological conditions is therefore essential for enhancing agricultural resilience and food security. This study evaluated 50 groundnut genotypes together with three farmer-preferred cultivars (Sodari, Tozi, and Kiriz) as checks under well-watered and drought-stressed conditions at Damazin Research Station (11°46′18.2″ N, 34°21′40.5″ E), Blue Nile Region, Sudan, during the 2016/2017 and 2017/2018 growing seasons. The experiment was conducted in the savannah agro-ecological zone using a split-plot design with three replications. Data were collected on leaf area index, chlorophyll content, root-to-shoot ratio, relative water content, 1000-seed weight, pod yield per plant, and seed yield per plant. Genotype, water regime, season, and their interactions significantly (P≤0.001) affected most of the evaluated traits. Drought stress reduced leaf area index, 1000-seed weight, pod yield per plant, and seed yield per plant by approximately 4.7%, 22.8%, 16.8%, and 24.8%, respectively, while chlorophyll content, root-to-shoot ratio, and relative water content increased by approximately 7.4%, 24.3%, and 13.4%, respectively. Several genotypes demonstrated superior and relatively stable performance under drought stress, particularly ICGV89242-F2B2-B1-B1-B-B, C97B-38-2, and ICGV-94198, while the farmer-preferred cultivars Kiriz and Sodari also performed well. These genotypes represent valuable genetic resources for breeding high-yielding, drought-tolerant, and climate-resilient groundnut cultivars adapted to drought-prone environments in Sudan.

Gene Action and Combining Ability for Yield and Panicle Traits in Sorghum under Semi-arid Conditions of Kenya

2026-10-03T11:21:34+00:00

Aims: To determine the nature of gene action and combining ability governing yield and panicle traits in sorghum (Sorghum bicolor L.) under semi-arid conditions of Kenya and to identify parental lines and cross combinations of potential value for breeding.

Study Design: A North Carolina Design II mating scheme was evaluated in a randomised complete block design with three replications.

Place and Duration of Study: KALRO Kiboko Sub-Centre, Makueni County, Kenya, during the 2020/2021 long and short rainy seasons.

Methodology: Two elite sorghum inbred lines (IESV23006DL and IESV23010DL) and two landraces (Redswazi and Wheatland) were crossed to generate four progenies. The progenies and parental checks were evaluated for days to 50% flowering, plant height, panicle length, panicle width, panicle yield, ear exsertion and seed set. Analysis of variance and combining ability analyses were conducted using GenStat 15th Edition.

Results: Significant genotypic variation (P ≤ .05) was detected for days to 50% flowering, plant height and panicle yield. General combining ability effects were significant for several traits, and the GCA/SCA variance ratio exceeded one for panicle length, panicle width and panicle yield, whereas it was below one for days to 50% flowering and plant height. IESV23010DL showed significant negative GCA effects for days to flowering and plant height, while Redswazi showed a positive GCA effect for panicle yield. Significant SCA effects were detected for days to flowering in IESV23006DL × Redswazi and IESV23010DL × Redswazi, and for panicle length in IESV23010DL × Wheatland.

Conclusion: Both additive and non-additive genetic effects contributed to variation in the evaluated traits. The results indicate that selection may be useful for traits with a relatively greater GCA contribution, while hybrid evaluation may be useful where non-additive effects are relatively more important. The identified parental materials and crosses warrant further evaluation across environments before use in breeding programmes.

Evaluating Seedling-Stage Salinity Resilience in Bangladeshi Wheat (Triticum aestivum L.) Cultivars via Multivariate and Physiological Profiling

2026-10-06T09:56:08+00:00

Soil salinity constrains wheat establishment, particularly during germination and early seedling development. This study evaluated the morphological, physiological, and biochemical responses of four wheat cultivars—BARI Gom 33, BARI Gom 28, BARI Gom 26, and BARI Gom 22—exposed to salinity levels of 0, 4, 8, and 12 dS m⁻¹ under controlled conditions. The experiment was arranged in a completely randomised design with three replications. Germination percentage, shoot and root length, fresh and dry biomass, SPAD-based relative chlorophyll content, Na⁺ and K⁺ concentrations, the Na⁺/K⁺ ratio, and proline content generally increased. SPAD values also varied among salinity treatments and cultivars, but these measurements should be interpreted as indicators of relative chlorophyll content rather than as measures of direct photosynthetic efficiency. Among the evaluated cultivars, BARI Gom 22 showed comparatively better performance under the highest salinity treatment, maintaining 51.67% germination; shoot and root lengths of 8.35 and 5.17 cm, respectively; a Na⁺/K⁺ ratio of 0.398; a proline content of 4.37 μmol g⁻¹ FW; and a SPAD value of 59.52. Correlation, principal component, and hierarchical clustering analyses demonstrated clear associations among growth, ionic, and biochemical traits across salinity treatments. Overall, the results indicate comparatively greater seedling-stage salinity tolerance in BARI Gom 22 among the four cultivars evaluated. Further field-based assessment is required to determine whether this response is maintained through later developmental stages and ultimately translates into improved grain production under saline conditions.

Genetic Diversity and Proximate Grain Quality Variation among Pearl Millet (Pennisetum glaucum (L.) R. Br.) Genotypes in North Darfur in Sudan

2026-10-09T09:43:07+00:00

Pearl millet (Pennisetum glaucum (L.) R. Br.) is an important climate-resilient cereal crop with considerable potential for improving food and nutritional security in dryland regions. This study evaluated 23 pearl millet genotypes for physical and proximate grain-quality traits and quantified the magnitude of genetic variability and expected response to selection. The evaluated traits included 100-seed weight, granule size, swelling power, moisture content, crude protein, crude fat, crude fibre, crude ash and carbohydrate content. Substantial phenotypic variation was observed among genotypes. The 100-seed weight ranged from 0.5 to 1.7 g, granule size from 1.6 to 10.9 mm³, and swelling power from 1.5 to 1.8%. Moisture content ranged from 4.9 to 6.2%, while crude protein, fat, fibre, ash and carbohydrate contents ranged from 15.4–17.2%, 3.3–4.6%, 7.2–11.6%, 1.0–2.4% and 28.7–34.5%, respectively. The genotype FSN-5 recorded the highest protein (17.2%), fibre (11.6%) and carbohydrate (34.5%) contents, whereas the genotype Sheikan had the highest fat (4.6%) and ash (2.4%) concentrations. Analysis of variance showed highly significant genotypic differences (P < 0.001) for the major proximate traits. Genetic parameter estimates further demonstrated strong genetic control, with broad-sense heritability ranging from 91.5% for crude fat to 99.7% for crude fibre. GCV and PCV were closely comparable, particularly for fibre (37.4 and 37.5%) and ash (37.6 and 37.8%), indicating limited environmental influence on phenotypic expression. Genetic advance as a percentage of the mean was highest for crude fibre (179.3%), followed by ash (122.8%), fat (119.7%) and carbohydrate (63.0%). The results demonstrate substantial exploitable genetic variation for pearl millet grain nutritional quality and indicate strong prospects for phenotypic selection, particularly for fibre, ash, fat and carbohydrate content. The identified variability provides useful opportunities for developing pearl millet cultivars with improved nutritional and processing attributes.

Genetic Response of Some Groundnut (Arachis hypogaea L.) Genotypes to Severity of Early and Late Leaf Spot (Cercospora spp) Diseases in Southern Guinea Savannah of Nigeria

2026-10-10T13:47:06+00:00

A field experiment was conducted during the 2015 and 2016 cropping seasons to assess the genetic response of groundnut genotypes to the severity of early and late leaf spot diseases at the Teaching and Research Farm of the Federal University of Agriculture, Makurdi, Benue State, Nigeria. Thirteen treatments (groundnut genotypes) used in the disease assessment were Campalla, Samnut-10, Aloshi, Tisha-1, Benue AGR, Ijiwanda, Samnut-22, Borno Brown, Borno Red, Dan-Bomboyo, Samnut-21, Shar-nya, and Ex-Dakar. The treatments were laid out in a randomised complete block design (RCBD) and replicated four times on a 40 x 17 m area containing 52 subplots; each subplot measured 3 x 2 m. Two seeds were sown per hole on each of four ridges, and no synthetic chemical was used. The results revealed significant (P ≤ 0.05) differences among the groundnut genotypes in establishment count, disease severity, combined disease severity, leaf defoliation, fresh leaf yield (kg/ha), fresh pod yield, and 1000-seed weight in both cropping seasons. All treatments expressed different levels of early leaf spot disease severity from 50 to 57 DAS and late leaf spot disease severity from 64 to 71 DAS in both seasons. Combined disease severity showed that Borno Brown, Campalla, Samnut-10, Samnut-21, Samnut-22, and Tisha-1 were resistant (R) to early leaf spot disease; Ijiwanda was moderately susceptible (MS), whereas the remaining groundnut genotypes were moderately resistant (MR) at 57 DAS. Similarly, Aloshi, Benue AGR, Borno Red, Campalla, Dan-Bomboyo, Ex-Dakar, Ijiwanda, and Shar-nya were highly susceptible (HS) to late leaf spot disease; Borno Brown, Samnut-22, and Tisha-1 were very susceptible (VS); Samnut-10 was moderately resistant (MR); and Samnut-21 was moderately susceptible (MS) at 71 DAS. Samnut-21, Samnut-10, Tisha-1, and Samnut-22 had higher fresh leaf yields in 2015, while Tisha-1, Samnut-21, and Samnut-22 recorded higher fresh leaf yields in 2016. Samnut-21, Samnut-22, and Samnut-10 had higher fresh pod yields in 2015, while Samnut-21, Samnut-10, and Tisha-1 had higher fresh pod yields than the other genotypes in 2016. Samnut-21 and Campalla had higher 1000-seed weights than the other groundnut genotypes in both seasons. Hence, resistant and moderately resistant groundnut genotypes with high-yielding traits are recommended as a suitable alternative management option for groundnut leaf spot (Cercospora spp) diseases in this region because of their economic benefits compared with synthetic fungicides, which may be economically infeasible and may pose environmental and human health risks.

Screening of Cowpea (Vigna unguiculata L.) Germplasm in a Screenhouse for Novel Aphid Resistance

2026-10-12T10:46:51+00:00

Cowpea [Vigna unguiculata (L.) Walp.] is an important nutritional and economic grain legume; however, its productivity in Kenya remains low because of various stresses, including aphid infestation. The use of synthetic insecticides for aphid control negatively affects the environment, thereby limiting continued reliance on them. Introduction of high-yielding and aphid-resistant germplasm could help increase productivity in a sustainable manner. This study aimed to assess the response of 60 cowpea accessions to imposed aphid stress with the goal of identifying resistant accessions. It was conducted using a randomised complete block design with three replications in two trials. Data were recorded on cowpea growth, yield and aphid infestation parameters at various time intervals and subjected to analysis of variance at P = 0.05. Results revealed highly significant (P<0.05) differences for all phenotypic traits assessed. In trial 1, days to 50% flowering ranged from 45 (NA20) to 61 (NA62), and grain yield ranged from 11.3 (NA28) to 1158.8 (MA29) kg/ha; in trial 2, the corresponding ranges were 48 (NA4) to 61 (MA67) days and 15.6 (BS01) to 389.3 (NA57) kg/ha. The grain yield was negatively (P<0.05) correlated with days to 50% flowering, but positively (P<0.05) correlated with leaf length in trials 1 and 2, respectively. There was a significant difference (P<0.05) in aphid population pressure (APP) and aphid damage severity (ADS) at 5 to 21 days after infestation (DAI). At 21 DAI in trial 1, the average number of aphids per plant ranged from 219 (NA71) to 24.5 (MA48), while in trial 2, it ranged from 113.5 (NA20) to 12.2 (MA22). The summarised ADS scores were 4 for 22 accessions and 3 for 38 accessions in trial 1, whereas in trial 2 they were 4 for 2 accessions, 3 for 54 accessions, and 2 for 4 accessions. The accessions with the lowest grain yield loss may be stable against aphids in major cowpea growing regions in Kenya. The four accessions showing great resistance (KK03, MA10, MA22, MA44) to aphid infestation should be evaluated in multiple field sites to confirm their resistance to aphids, followed by deployment to areas prone to high aphid infestation to minimize pesticide reliance and associated negative effects. Furthermore, they should be validated using molecular markers to confirm their resistance genes before incorporating them into farmers’ preferred, but susceptible varieties to boost their resistance to aphids.

Beyond Conventional Fertilization: Integrating Soil Stoichiometry, Microbiomes and Crop Demand for Sustainable Nutrient Management

2026-10-16T04:56:29+00:00

Synthetic fertilisers have supported modern crop production, but nutrient use efficiency remains constrained by losses, nutrient imbalances and the biological processes that regulate nutrient availability. This review examines sustainable nutrient management by integrating three complementary perspectives: soil ecological stoichiometry, soil and rhizosphere microbiomes, and dynamic crop nutrient demand. It synthesises evidence showing that carbon, nitrogen and phosphorus ratios influence microbial growth, nutrient immobilisation and mineralisation, while microbial communities regulate nitrogen transformations, phosphorus mobilisation and root access to nutrients. Crop nutrient requirements are shown to vary with genotype, phenological stage and root acquisition traits, making temporal and spatial synchrony between nutrient supply and crop demand essential. The review also evaluates microbial inoculants, organic amendments and precision nutrient-management approaches, emphasising that their effectiveness depends strongly on soil conditions, resource balance and biological context. An integrated diagnose–amplify–deliver framework is presented in which soil and microbial diagnostics guide the strengthening of biological nutrient supply and the targeted delivery of mineral nutrients according to crop demand. The synthesis indicates that this approach could improve nutrient use efficiency while reducing unnecessary nutrient surpluses, although its practical application requires locally calibrated indicators, field validation, reliable microbiome interventions and accessible decision-support tools. The framework also recognises contrasting regional priorities, from reducing excessive nutrient inputs to rebuilding fertility in nutrient-depleted systems.