No-till Research Articles

Promoting synergy among environmental and economic performances in food waste treatment by optimizing biogas residue management practices.

Improper management of biogas residue (BR) can reduce sustainability in the food waste treatment industry. To address this issue, a comprehensive evaluation framework, based on emergy analysis, carbon emissions and economic analysis, is proposed in this study, to explore how different BR disposal practices affect the comprehensive performance of the industry. A food waste treatment plant in Henan Province, China (anaerobic digestion (AD) + BR landfilling: Scenario 1 [S1]), and two alternative scenarios (S2: AD + BR incineration; S3: AD + BR composting) are investigated as a case study. Compared with S1, S2 and S3 reduce carbon emission intensity by 16.93 % and 22.92 %, respectively; S2 enhances environmental sustainability by 48.63 % while S3 reduces the environmental sustainability by 11.64 %. Furthermore, S2 and S3 improve economic benefits by 8.70 % and 43.48 %, respectively. Generally, S2 and S3 increase the system coordination degree by 9.35 and 9.52 times, respectively. Therefore, BR management should be devoted to improving the resource structure in the future.

Sustainable tillage and residue management for enhanced soil health and productivity in North Bihar’s rice–wheat-green gram system

Sustainable tillage and residue management for enhanced soil health and productivity in North Bihar’s rice–wheat-green gram system

Influence of Eimeria spp. and Clostridium perfringens Infection on Growth Performance and Toltrazuril Residues in Chickens.

Coccidiosis and necrotic enteritis are among the most common diseases affecting poultry, with economic impact due to reduced production and the costs of treatment and prevention. Eimeria invasion contributes to gut damage that promotes the growth of other harmful pathogens, such as Clostridium perfringens. Coccidiostats, with toltrazuril as an example, are widely used to control these infections. In this study, we assessed the effects of Eimeria spp. infection and coinfection with Eimeria spp. and Clostridium perfringens on chicken weight and toltrazuril concentrations, along with two metabolites-toltrazuril sulfoxide and toltrazuril sulfone-using liquid chromatography coupled with mass spectrometry. The analysis of liver and muscle samples showed lower levels of residues in groups challenged with Eimeria spp. In the case of combined Eimeria and C. perfringens infection, no significant differences were observed. These findings suggest that the combination of Eimeria and C. perfringens does not significantly alter the residue levels of toltrazuril and its metabolites, providing valuable insight into the pharmacokinetics of toltrazuril in poultry under infection conditions. This research contributes to optimizing drug use and residue management in poultry production.

Enhancing Soil Health in Rice Cultivation: Optimized Zn Application and Crop Residue Management in Calcareous Soils

Enhancing Soil Health in Rice Cultivation: Optimized Zn Application and Crop Residue Management in Calcareous Soils

Resiliência de plantas de cobertura à seca

Straw production from cover crops and the sustainability of no-tillage farming systems can be compromised by low rainfall during the dry off-season in Central Brazil. This study investigated the drought resilience of five cover crop species under drought stress conditions. Three irrigation levels [100% pot capacity – CV (well-watered conditions), 60% CV (moderate drought stress) and 25% CV (severe drought stress)] and five grass cover crop species [Urochloa brizantha cv. BRS Piatã, U. brizantha cv. Marandu, U. brizantha cv. Xaraés, U. ruziziensis cv. Comum and Pennisetum glaucum cv. ADR 300] were tested using a randomized block design with a 3 × 5 factorial arrangement and three replications. Canonical variable analysis (CVA) and a correlation network were established with the variables evaluated. The CVA showed that 88.6% of the total variation of the data was retained in the first two canonical variables. The plants were exposed to water stress for 25 days during the tillering and stem elongation phases. Plants of the genus Urochloa (U. ruziziensis, U. brizantha cv. Marandu, and U. brizantha cv. Xaraés) showed higher total dry matter production under normal irrigation conditions. However, under moderate water stress conditions, U. ruziziensis was the cover crop with greater resilience, since these conditions culminated in higher dry matter production.

Impacts of Climate-smart Agriculture on Crop Production: A Review

Climate change(CC) factors worldwide have negatively impacted crop production. Temperature, precipitation, and greenhouse gas emissions have influenced soil fertility, irrigation resources, plant physiology, and metabolic activities in crops. Afghanistan has also encountered climate change factors, such as drought, that decreased crop production. A technologically sophisticated solution to the problems facing agriculture due to CC is called Climate-smart Agriculture (CSA). Crop rotation, crop residue management, and soil and water conservation are called Climate-smart Agriculture Practices (CSAP). It is reported that CSAP increased water use efficiency and total water storage by 9–68% and 1–13%, respectively. Furthermore, implementation of CSAP increased wheat yield by 30-45%. Although the adaptability of CSA has been investigated, little is known about the impacts of CSA on crop production. Thus, it is necessary to describe the impacts of CC on crop production and investigate widely. The review was stated to provide some understanding and recommendations on earlier studies on the topic. The review's objective is to determine the optimal CSAP that decreases the adverse effects of CC on crop production. Researchers, consultants to farmers, and policymakers can benefit from synthesizing all this information as it may help provide favorable plans to boost crop production by selecting and using relevant CSAP.

ENTERAL NUTRITION OF PRETERM INFANTS (2022): A POSITION PAPER FROM THE EUROPEAN SOCIETY FOR PAEDIATRIC GASTROENTEROLOGY, HEPATOLOGY AND NUTRITION AND INVITED EXPERTS

A professional translation into Ukrainian of the updated ESPGHAN Nutrition Committee consensus statements and recommendations on nutrient intake and nutritional management for preterm infants with birth weight <1800 g. These recommendations can be used in clinical practice, but highlight the lack of convincing evidence in several topic areas and the need for further high quality research, especially studies that assess long-term functional outcomes. The article is accompanied by additional digital content that provides a more complete explanation of the literature and relevant physiology: introduction and overview; background on human milk; intake of water, protein, energy, fat, carbohydrate, electrolytes, minerals, trace elements, water-soluble vitamins and fat-soluble vitamins; feeding regimen, including minimum enteral feeding, rate of increase in feeding volume, management of gastric residues, gastric tube placement and bolus or continuous feeding Growth; breast milk, oral colostrum, donor breast milk and risk of cytomegalovirus infection; hydrolysed protein and osmolality; supplemental bionutrients and use of breast milk fortification.

Response of tillage method and residue management on productivity and soil biological properties of wheat

The field study was undertaken at the Main Agriculture Research station, University of Agricultural Sciences, Dharwad during the rabi season of 2020–21 and 2021–22 to find out the effects of tillage and residue mulch on yield and economic parameter of wheat and its soil enzymatic properties. Conventional tillage recorded higher number of productive tillers/m2 (418.8), number of grains/spike (35.9), grain weight/spike (1.74 g) and thousand grain weight (34.88 g). The statistically highest grain (3.30 t/ha) and straw yield (5.44 t/ha) of wheat was obtained under conventional tillage compared to minimum tillage. The gross returns were highest with conventional tillage and B:C ratio was higher with minimum tillage. Glyricidia mulch recorded higher yield attributes, grain (3.50 t/ha), straw (5.64 t/ha) yield and harvest index (36.88%) compared to maize, soybean, groundnut and no residue. No residue recorded lower yield parameter. Soil enzymatic activity was higher with glyricidia mulch compared to no residue, maize, groundnut and soybean mulch. Minimum tillage with glyricidia residue mulch improved soil biological enzymes of dehydrogenase (45.4 and 27.4 μg), phosphatase (187.9 and 109.8 μg), urease (12.6 and 7.6 μg) activity. Weed free check registered markedly superior yield and economic parameter and lower enzyme activity.

Integrating insect dynamics in agricultural ecosystems: the role of predators, prey, and sustainable practices in enhancing biodiversity and ecosystem resilience

Abstract Insects play a pivotal role in food webs, influencing ecosystem stability through their interactions as herbivores, predators, and prey. This review explores the impact of agricultural practices on insect dynamics, focusing on how no-till farming, mulching, crop residues, and diverse farming systems like intercropping and crop rotation can shape predator-prey interactions. No-till systems, by reducing soil disturbance, enhance the survival of natural enemies such as ants, spiders, and beetles, indirectly regulating pest populations. Practices like mulching and maintaining crop residues hinder pests’ ability to locate host plants, boosting the abundance of natural predators. Additionally, crop rotation and intercropping create varied habitats, supporting a higher diversity of predators and improving biological pest control. These integrated approaches not only reduce reliance on chemical pesticides but also foster ecological balance and enhance agricultural sustainability. The review highlights the importance of sustainable land-use practices in preserving insect biodiversity and improving ecosystem resilience. Keywords: Biodiversity, food web and predator-prey interactions.

Climate-smart agriculture: A review of sustainability, resilience, and food security

This paper investigates Climate Smart Agriculture (CSA), a comprehensive strategy aimed at improving agricultural efficiency and sustainability while addressing the challenges of climate change. It examines the economic advantages of CSA for adopters compared to traditional farming methods and assesses CSA's role in mitigating climate change, adapting to its impacts, and enhancing food security. The study reviews essential CSA practices, including agroforestry, conservation agriculture, water-efficient irrigation technologies, crop diversification, improved livestock management, and soil carbon sequestration, as well as the barriers to adoption, such as limited funding, arable land, land tenure issues, and insufficient expertise. Agroforestry and crop rotation have shown encouraging results, with agroforestry serving as a cost-effective solution for food production and environmental preservation. Dairy companies boosted milk consumption from 529,000 to 3 million liters, while farmer profits grew from $0.2 to $0.3 per liter. Rice yields have increased, from 3-4 tons to 7.5 tons per hectare. In cotton farming, CSA adopters cut input costs compared to traditional methods, resulting in long-term economic gains. Crop rotation increased maize productivity by 5–10%, while new irrigation techniques improved water efficiency by 5–35%. However, regions without CSA methods experienced significant livestock losses, highlighting the importance of widespread adoption to ensure resilience. Despite CSA’s advantages, its widespread adoption is hindered by financial and knowledge barriers. Future research should focus on optimizing multiple cropping systems, crop diversification, and no-till agriculture. CSA, particularly when integrated with technologies like the Internet of Things (IoT), offers a promising path toward more adaptive and resilient agricultural practices. Broader adoption will require investments in research and resources to effectively scale CSA innovations.

Design, Development and Evaluation of Baling Attachment with Self-Propelled Combine Harvester

Paddy cultivation is practiced in about 3.17 Mha in Punjab, generating more than 22 Mt of paddy straw. To curb the practice of paddy residue burning, better straw management strategy is needed. A baling attachment with the self-propelled combine harvester was designed, developed and evaluated for baling of loose straw, which enabled simultaneous harvesting and baling operation of rice straw. The developed baling attachment with self- propelled combine harvester consisted of a rectangular baler with a rear cover attached to it and a flat belt conveyor system for conveying the loose paddy residue from the straw walkers to the baler feeder system. Two types of paddy varieties (PR 126, PR 122), two levels of forward speed (F1=2.0 and F2=2.5 km h-1) and three levels of belt conveyor speed (B1=1.15, B2=1.40 and B3=1.50 m s-1) were selected for the study. The mean straw walker loss (1.44%) and mean sieve loss (0.39%) were higher for paddy variety PR 122 compared to paddy variety PR 126 with 1.41% mean straw walker loss and 0.36% mean sieve loss. It was due to higher loose straw load of paddy variety PR 122 (6.0-6.5 t ha-1) as compared to paddy variety PR 126 (5.0-5.5 t ha-1). The forward speed F2 resulted in higher mean straw walker loss (1.45%) and mean sieve loss (0.43%) as compared to forward speed F1 with 1.39% mean straw walker loss and 0.32% mean sieve loss. The highest mean straw walker loss (1.45%) occurred at B3 with no significant effect on sieve loss. The mean fuel consumption for paddy varieties PR 122 and PR 126 was 25.60 and 24.68 l ha-1 respectively, while at forward speeds of F1 (2.5 km h-1) and F2 (2.0 km h-1), the mean fuel consumption was 23.24 and 27.03 l ha-1, respectively. The mean effective field capacity was 0.64 ha h-1 at forward speed F1 and 0.47 ha h-1 at F2. The best operational parameters based on minimum straw walker and sieve loss were F1B1, F1B2 and F1B3 while F2B1, F2B2 and F2B3 were optimal based on less fuel consumption and higher field capacity. The baling attachment enabled efficient paddy residue management for zero-till wheat drilling.

Impact of Crop Residue Management on Soil Health under Rice- Wheat Cropping System in Southern Bihar, India

The study investigates the effects of paddy straw bale management on soil health and the productivity of a rice-wheat cropping system in Southern Bihar. Conducted from 2021 to 2023, the experiment involved four treatments: control (FP), tillage + recommended dose of fertilizer (RDF), zero tillage (ZT) + mulching, and burning + ZT (RDF). Soil samples and crop yields were analyzed to evaluate physico-chemical properties, microbial activities, and economic viability. Results revealed that ZT + mulching significantly enhanced soil properties, including organic carbon, nutrient availability (NPK), and microbial activity, compared to other treatments. Grain and straw yields were highest under ZT + mulching for both rice (80.01 and 84.25 q ha-1) and wheat (53.4 and 57.35 q/ha), with improved plant height, panicle density, and grain quality. Economic analysis indicated the highest benefit-cost ratio under ZT + mulching (3.18 for rice and 2.92 for wheat). This sustainable practice demonstrated its potential to mitigate residue burning's negative impacts, enhance soil health, and boost productivity, offering a viable strategy for long-term agricultural sustainability in the region.

Lands Evaluation in Hydromorphic Environment: Case of Developed Rice Lowland Soils in the Province of Ziro, Burkina Faso

Sustainable soil management became a major concern for rice farming in Burkina Faso. Rained rice production offers potential thanks to the national rice policy oriented towards the developing of lowlands. However, effective soil fertility management through the promotion of good agricultural practices is essential in this agricultural area to meet the goal. It involves the evaluation of the land, as it can provide important information on which to base rational decisions on land management. A study was carried out in order to promote soil fertility sustainable management on two rice-growing lowlands in the province of Ziro. The soils of the sites were characterized and sampled for the physicochemical parameters analysis. The suitability of the soils for rice cropping was thus assessed. It emerges from the study that the dominant soils in the developed rice lowlands are hydromorphic soils. The hydromorphic soils are suitable types of soils for rice production. The results on the physical parameters show that the soils of the lowlands mainly have a coarse surface texture. The organic matter content is low and the pH values vary from weakly to very strongly acidic. The useful soil water reserve is medium to high. The contents of the major nutrients (N, P and K) are very low as are the values of the CEC, which indicates a low level of chemical fertility of the soils according to the complete range. The evaluation of rice lowlands revealed that soils are moderately suitable for rice production and their major constraint is the availability of nutrients. Current producer practices related to soil fertility management are unfavorable to sustainable land management. The study shows the need for appropriate crop fertilization, better management of crop residues and periodic monitoring of fertility essential parameters for the sustainability of soil productivity.

Wheat productivity and nitrogen use efficiency in no-till systems: a comparative analysis of crop-pasture and continuous cropping rotations in Uruguay

IntroductionUruguayan agriculture’s transition to no-till farming and intensified practices, replacing crop-pasture (CP) systems with continuous cropping (CC) rotations, has disrupted biological nitrogen fixation (BNF). Despite this, diversified cropping sequences, including C4 species, have maintained the soil organic carbon (SOC) balance under no-till management, with limited overall impacts on productivity and sustainability. The effects of these changes on wheat productivity and nitrogen use efficiency (NUE) need to be further investigated.MethodsThis study, conducted within a long-term experiment (LTE) under rainfed conditions, compared wheat productivity in CP and CC rotations. Wheat following CP and CC were analyzed over three seasons. Variables measured included soil nitrogen (N) concentration, wheat grain yield (WGY), grain protein concentration (GPC), and NUE. Four N fertilizer levels were applied to each rotation system to assess their impact.ResultsCC rotation consistently outperformed CP in WGY, with 2425 and 1668 kg ha−1 averages, respectively. CP showed slightly higher GPC (10.92%) than CC (10.48%). Nitrate-N levels at tillering positively correlated with WGY and negatively with GPC, but the relationship differed by rotation. Soil NUE indices were higher in CC rotations.DiscussionThe study’s findings highlighted the potential of CC rotation, especially when including C4 species in the crop sequence, to achieve higher wheat productivity in the short term due to healthier soil conditions compared to wheat seeded after post-pasture in CP. Additionally, our study highlights that the effect of the previous crop on yield and NUE in wheat was more relevant than the expected residual effect of the pasture phase in CP, primarily due to the quality of residues and the temporary adverse effects of soil compaction caused by livestock trampling.

Nutrient Distribution in the Soil Profile Under Different Tillage Practices During a Long-Term Field Trial

Conservation tillage practices are increasingly used in agricultural systems. However, these practices require a complex approach regarding soil nutrition. Adequate nutrient content in soils is important for crop production, as reduced and no-tillage practices change the distribution of nutrient contents (P, K, Mg, and Ca) in the soil profile, necessitating new approaches for agronomists in crop nutrition. Little is known about the time changes in nutrient distribution in the soil profile under conservation tillage practices. Long-term field experiments with conventional (CT—plowing to 20–22 cm), reduced (RT—chiseling to 8–10 cm), and no-tillage (NT) practices were established in Prague–Ruzyně (Czech Republic) in 1995. This four-year crop rotation consisted of winter wheat changing with oilseed rape or pea. The soil nutrient contents have been determined since 2009 using the Mehlich 3 method and through extraction in 0.5 M ammonium acetate. The obtained results showed that P, K, and, to a lesser extent, Mg contents increased in the soil surface layer (0–10 cm) under the reduced and no-tillage practices, whereas Ca and pH values showed an opposite trend. We found an unbalanced ratio of nutrients in the upper soil layer in RT and NT caused by a high concentration of the monovalent cation K+ and the leaching of the divalent cations Ca2+ and Mg2+ into the deeper soil layers. In conventional practices, the ion contents are equalized throughout the topsoil due to the soil inverting during plowing. The determination of nutrient contents in deeper soil layers revealed that, over time, calcium, magnesium, and potassium were transported to deeper parts of the soil profile under RT and especially NT. Low nutrient ratios were found in the surface layer under RT and NT, negatively affecting the quality of the soil surface layer, including its structure. Fertilizer management and nutrient ratios in soils under RT and NT should be considered to maintain and possibly improve sustainable agricultural practices in fields with reduced or no-tillage practices. Furthermore, nutrient contents and their mutual ratios should be evaluated in more soil layers under these systems, enabling the detection of eventual problems in the upper layer that must be addressed by changing fertilization.

Effect of potassium rates and application methods in no-till on soil K availability and crop yield

ABSTRACT The combination of potassium (K) fertilization with the adoption of no-tillage (NT) increases the concentration gradient of K in the soil, requiring subsurface layers to diagnose fertility. This study aimed to evaluate the effect of K rates applied in band or broadcast on the soil K availability and soybean and wheat yield. The study was established in 2019 on a Latossolo (Ferralsol) in the northwest of Rio Grande do Sul State, Brazil, under NT since 2002. Summer soybeans and winter wheat were cultivated from 2020 to 2022, and rates of K (0, 50, 100, 150, and 200 kg ha -1 ) were applied annually at soybean sowing. Each rate of K was applied in a band at the seeding row or broadcast on the soil surface. Grain yields and the available K content in the soil at different soil layers (0.00-0.05, 0.05-0.10, 0.10-0.15, and 0.15-0.20 m) were evaluated after the soybean harvest in 2020/2021. The K applied remained close to the application site, at the 0.10-0.15 m layer when applied in band and at the 0.00-0.05 m layer when deposited by broadcast. Band application of K can decrease the K gradient and increase soybean and wheat yield when the available K content is below 64 mg dm -3 in the 0.10-0.20 m soil layer, coinciding with the critical level adopted in the south of Brazil until 2016. The replacement of K removed by soybean and wheat grains under NT with low soil K availability at 0.10-0.20 m should be band applied in-furrow along the sowing line.

Soil Water Capacity and Pore Size Distribution in Different Soil Tillage Systems in the Spring Barley Crop

Barley is an important cereal crop with versatile uses: barley grains are part of the human diet and are also used for animal feed, while the potential to use barley for ethanol production provides this grain with a promising bioenergy potential. As scientific research in the field of bioenergy progresses, barley may play an even greater role in meeting the world’s future energy needs. The challenge facing today’s barley growers, and one that will undoubtedly be addressed by future generations of grain farmers, is how to grow higher yields with lower costs while minimizing damage to the soil. One way to achieve this is by using simplified tillage methods, thereby avoiding soil compaction, structural degradation, and erosion. Moreover, studies have shown that when soil is cultivated using simplified methods, crop yields may actually increase. Our research was conducted in a long-term stationary field experiment, which was located at the Vytautas Magnus University Agriculture Academy Experimental Station. The aim of the investigation was to determine the effect of conservation tillage and deep plowing systems on soil water capacity and pore size distribution in spring barley cultivation. Comparing simplified tillage systems with deep plowing (DP), it can be concluded that the no-tillage (NT) technology most significantly improved the studied indicators, while the deep plowing (DP) technology exhibited the poorest results.

Biogas Potential Assessment of Co-digestion of Various Wastes (Cassava Residues, Poultry Droppings and Household Waste) in the Gbêkê Region, Bouaké, Central Ivory Coast

Assessing the potential for biogas from cassava residues, poultry droppings and household waste in Bouaké will help determine the viability of a sustainable energy project. Cassava is abundant in this region, and its exploitation produces starch-rich residues, a potential source of biogas through anaerobic digestion. Poultry droppings from livestock farming and household waste are respectively sources of biomass rich in nitrogen and various organic materials. Unfortunately, poor management of these wastes leads to environmental problems, including foul odors that encourage disease, and soil and groundwater pollution. It is therefore necessary to quantify this waste with a view to transforming it into renewable energy. To do this, we began by collecting cassava residues and household waste from attiéké production cooperatives and some restaurants, and poultry droppings from city farms. After collection, we sorted and mixed the different types of waste with water, then filled the digesters. And finally, we made different formulations from these wastes for biogas production. During the process, the results obtained from the physico-chemical characteristics of the waste give respectively for pH 6.4 and 7.4, for BOD5 25 442 mg/L and 19 475 mg/L, for COD 74 400 mg/L and 62 100 mg/L, for MES 3 733 mg/L and 2 675 mg/L, for MS 11.6% and 8.1%, for VDM 64.3% and 58.2%. Concerning biogas composition and production, methane is estimated at 56.5% on average, with a standard deviation of 6.1, giving a biogas volume of 3.2 m3. These results provide valuable indications for the planning and development of biogas production facilities in Bouaké. They encourage the adoption of renewable energies, waste reduction and better management of organic residues, thus contributing to the environmental and economic sustainability of the region.

Tillage With Straw Returning Promotes Soil Functional Microbiomes and Nitrogen Transformation to Increase Cotton Yield

ABSTRACTThe soil microbial community and its driven nitrogen (N) conversion are the key processes in cotton production. However, the responses of soil microbial communities to changes in farming practices (e.g., tillage and straw returning) remain unknown. This study sampled soil from the 0–20 cm and 20–40 cm layers of cotton fields under no‐tillage (NT), tillage (T), no‐tillage + straw returning (NT + SR), and tillage + straw returning (T + SR) practices, and high‐throughput sequencing approach method was used to investigate the effects of farming practices on soil physicochemical properties, microbial community structure, and N metabolism pathways, as well as their associations with cotton yield. The survival rate (90.44% ± 0.90%) and yield (5314.0 ± 57.04 kg/ha) of cotton were highest under T + SR, and T improved cotton yield more effectively than SR. T increased the relative abundance of beneficial microorganisms and mediated their assimilation of ammonium nitrogen (NH+ 4‐N) by improving the soil physical properties. In addition, the survival rate and yield of cotton were primarily related to the fungal communities and their pathways of assimilating NH+ 4‐N because fungi had more complex and stable networks. The core microbiota contained most of the taxa that were significantly associated with N cycling genes and cotton yield, and even rare taxa could play an important role in microbial function. This study improves our understanding of the microbial N mechanism; T combined with SR can improve soil quality and establish healthy soil microflora (fungal‐dominated type) to improve cotton production.

Relative impact of factors affecting penetration rate of horizontal directional drilling

Prediction of the penetration rate (PR) of horizontal directional drilling (HDD) depends almost entirely on the experience of practitioners. This has resulted in actual values of PR that are inconsistent with the predicted ones. The problem stems from the many factors that are involved in the process and the need to assess their relative importance. To determine the factors that significantly affect PR and their relative importance, semi-structured interviews were conducted with HDD experts and a questionnaire was sent to other experts worldwide. The obtained responses are presented and discussed in the current paper. It has been found that ten factors significantly affect PR. The highest three factors are ‘ground type and condition’, ‘geotechnical investigation’, and ‘operator experience’. The two factors ‘geotechnical investigation’ and ‘steering engineer experience’ which are newly introduced in this study are ranked as the 2nd and 5th most important, respectively. The interrelationships between factors are also discussed. The obtained findings show reasonably good comparison with observations of actual HDD works. On the basis of Pareto analysis made on the obtained responses, it has been found that the top 10 factors represent 72% of the effect on PR. In addition, implications for actual HDD works are presented.