Mulch Research Articles

Optimization of Organic Mulches Thickness Improves Soil Moisture Retention under Controlled Conditions

Organic mulch can improve the moisture, chemical composition, dust, and dust suppression of soil, and beautify the environment. In view of the rapid evaporation rate and serious loss of soil water in tropical areas, this paper explored the effect of organic mulch materials with different thickness on the increase of soil water retention rate and the improvement of soil water loss caused by evaporation. Rubberwood sawdust (RWS), rubberwood bark (RWB), coconut fiber (CF), and Mulch (MC) were selected as the mulching materials. Field experiment and laboratory experiment were performed, and soil-moisture content and temperature were continuously monitored. However, from the daily measurement of water content at constant conditions (29°C ± 0.2°C, 74% ± 1% air RH) in the laboratory experiment, the results of variance analysis (ANOVA) showed that there was no significant difference between the soil-water content of covered samples and bare soil (P > 0.05). In the field experiments, the analysis of variance indicated significant differences in the soil-moisture content owing to the effect of the covering material (P

Effects of Fertilisation Using Organic Waste Products with Mineral Complementation on Sugarcane Yields and Soil Properties in a 4 Year Field Experiment

Sugarcane cultivation is suitable for the exploitation of organic waste products. However, minimum complementary mineral input is necessary for optimal fertilisation. Control mineral fertilisation treatments with mulch (MCM) or without mulch (MC) were compared with two organic waste treatments, a pig slurry with mulch (PSM) and without mulch (PS), and a sugarcane vinasse with mulch (SVM) and without mulch (SV) on a Nitisol in French Reunion Island. The sugarcane yields obtained with the different treatments differed each year. However, no trend was observed and no significant and recurrent effect of the presence of mulch or of the different treatments was identified over the course of the 4 year experiment. Soil pHw and pH KCl measured in the different treatments increased from year 3 in with the treatments including organic waste products (PS, PSM, SV and SVM) but remained constant with the treatments including only mineral fertilisation (MC and MCM). With the exception of PS and PSM, which were significantly higher in year 4, soil organic carbon content was not modified by the treatments. Soil cation exchange capacity increased only slightly with the PS and PSM treatments from year 3 on. The differences in yields and soil properties can be explained by the nature of the organic waste products, the accumulation of nutrients after several applications, and the specific characteristics of the sugarcane crop. The improvement in soil properties from the third year on was not reflected in the yield of sugarcane because it was too weak, and the crop explores a much larger volume of soil.

Soil nutrients and crop yield response to conservation-effective management practices in the sub-humid highlands agro-ecologies of Kenya

Crop productivity in most smallholder farming systems in Sub-Saharan Africa experience low use of soil amendment resources, low and erratic rainfall, frequent dry spells, and droughts. Rain-fed agriculture has a high crop yield potential if rainfall and soil nutrient input resources are utilized effectively. Thus, in 2011, we set up an on-farm experiment in Meru South (sub-humid) and Mbeere South (marginal sub-humid) sub-counties in upper Eastern Kenya to assess conservation-effective management (CEM) practices effects on maize (Zea Mays L.) yields response and soil nutrients. The CEM practices were; tied ridging (TR), mulching (MC), and minimum tillage (MT), with conventional tillage (CT) as a control. There were frequent dry spells and droughts during the experimental period. The experiment ran for four seasons, from the long rains season of 2011 (LR11), short rains seasons of 2011 (SR11), long rains season of 2012 (LR12), short rains 2012 (SR12), and long rains season of 2013 (LR13). In Meru South, TR and MT treatments had significantly higher phosphorus content (100% and 66%, respectively) than the control. Also, in the same site, Cu and Zn were high in MT than in CT treatments. In the Mbeere South site, the aboveground biomass yield was significantly higher in TR treatment (by 71%) than CT during SR11, while in LR12 season, it significantly increased by 72% and 46% under MC and TR treatments, respectively, than the control. The TR treatment had significantly higher aboveground biomass than the control (84% and 115%) in the SR12 and LR13 seasons. In Meru South, MC treatment had significantly higher aboveground biomass, which was significantly higher, by 39%, during the SR11 season and 46% in TR treatment in SR12 season than the control. This study highlighted tied ridging as the best-fit practice for enhancing maize crop aboveground biomass production in rain-fed farming systems of marginal lands and sub-humid regions receiving unreliable rainfall. Further, we recommend longer-term experimentation to explore CEM effects on soil nutrients.

Identity is a Fragmentary System

Identity is one of the most important concepts dealt with in most recent studies, because it expresses the existence and belonging of the individual, and it is an integral part of his being, which he derives from the society to which he belongs. Identity is subjected to some difficulties and problems such as its fragmentation and tearing, and behind that stands several circumstances that led it to These conflicts, therefore, were the focus of attention of modern studies, and the novel has the largest share in this aspect in order to understand its importance, especially if it is related to the Arab identity based on Arabism, Islam and authenticity represented by customs, traditions, customs ... etc.
 The value of identity is evident in cultural studies that search for the texts of the text, uncover what is silent about it and what the discourse encircles in terms of the consistency of the context, and shed light on those cultural systems that have become fragmented in that identity and led to its fragmentation and tearing. For researchers and scholars to investigate its importance and its role in relying on the status of that identity and its specificity, and after that we stood on the procedural mulch to search for those cultural systems that have subsided behind the narrative texts in a way that is difficult to detect except through in-depth cultural reading.

Energy balance and temperature regime of different materials used in urban landscaping

In an effort to conserve water, conversion of irrigated lawns to “water-saving” landscape designs are being promoted in urban areas. Different materials, with different radiative and thermal properties, are used to accomplish this. We conducted a field study where we measured reflected spectral irradiance, albedo, energy balance, and soil and surface temperatures of grass (GR), artificial turf (AT), decomposed granite (DG), and hardwood mulch (MU) to better understand how surface temperature is controlled in landscapes composed of these materials. DG had the highest albedo and a large fraction of the reflected solar energy was in the visible band. AT had the lowest albedo and highest net radiation of the materials we tested. DG was the most efficient material in conducting energy into the subsurface, whereas MU was the least. Both AT and MU concentrated most of their thermal energy in the surface, indicating poor ability to diffuse thermal energy into the subsurface. Latent heat flux was the major component of the energy balance of GR, as expected. After GR, DG maintained the lowest surface temperature due to a combination of high albedo and high heat flux into the subsurface.

Phosphorus Rates and Mulching Materials on Establishment of Kentucky bluegrass by Seed

Phosphorus Rates and Mulching Materials on Establishment of Kentucky bluegrass by Seed

Conservation agriculture-related practices contribute to maize (Zea mays L.) yield and soil improvement in Central Malawi

Conservation agriculture-related practices (CARP) improve soil fertility, maize yield, and profitability. A study was conducted to generate evidence on the benefits of CARP in the long-term (nine years) in Salima District, Central Malawi. The objectives of the study were 1) to compare the maize yields between farmer practice and CARP interventions in the long-term, 2) to compare soil fertility changes between farmer practice and CARP interventions in the long-term, and 3) to verify the intercropping efficiency of maize with groundnut using the land equivalent ratio (LER) and land equivalent coefficient (LEC). A guiding hypothesis was that the application of CARP improves soil condition and maize yield. Farmer practice (FP) and three CARP [Pit planting + mulching (PPM), Intercropping + mulching (INM), and Mulching (MC)] treatments were tested in the study. INM was also tested for intercropping efficiency. Maize yields in CARP (3.98–4.43 Mg ha−1) were significantly higher (p < 0.018) than in FP (1.84 Mg ha−1). Soil pH, soil organic carbon, soil organic matter, nitrogen, and bulk density were acceptable for the Malawian soil in CARP compared to FP, suggesting that CARP improved soil fertility properties. There was no significant difference in soil potassium concentration across the treatments (p < 0.0642). The land equivalent ratio for maize and groundnut intercropping in INM was 1.77, indicating beneficial intercropping efficiency. The benefit-cost ratios (BCR) for PPM, INM, and MC were 1.55, 1.90, and 2.26, respectively, indicating that CARP interventions were more profitable than FP (BCR = 0.15). It is concluded that CARP interventions contribute to increased crop yield, income, and soil fertility restoration in the agricultural land. The selection of a CARP intervention should depend on the farmer's main intention, either to maximize yield, soil fertility, income, or a combination.

Assessing the rice straw effects on the soil erosion rate in forest road cut slope embankments

Applying rice straw as mulch blanket on recently-established embankment is one way to reduce the environmental impact of sediment yields from forest roads embankments. Effectiveness of straw, however, is often unknown and it is unclear how the rate of application should vary with factors such as slope. In this study, the effects of the percentage of straw cover and slope gradient in the embankment of forest roads on the runoff volume and soil erosion were studied using rainfall simulator in plots of 1 m × 1 m dimension. Straw effects were quantified in four treatments of rice straw cover (0%, 30%, 60% and 90%), three treatments of slopes (0-15%, 16-30%, and 30-45%), with three replications in each giving a total of 36 experimental plots. Runoff and sediment from each plot were recorded every two minutes during the simulated rainfall of 65 mm/h intensity for 16 minutes. The 16-min simulations divided into eight simulation periods. The results showed that an increase in straw cover (based on length and amount) resulted in an impressive decrease in the runoff volume and soil erosion. Moreover, investigating the effect of slopes indicated that the runoff volume was significantly different between 0-15% and 15-30% slope classes. In terms of sediment concentration (g mL-1) and sediment (g), there were significant differences between the study slopes (various slopes and covers). The results showed that rice straw can decrease soil erosion up to 90% in road embankments and the rice straw with the length of 5 cm was the most economical choice to protect soil from erosions.

Numerical simulation and analysis of mechanized suppression process of seedbed with whole plastic film mulching on double ridges

In order to achieve the construction standard of high mechanized performance of the seedbed with whole plastic-film mulching on double ridges, in this study, the forms of suppression failure were analyzed, and the key factors influencing the suppression performance were determined based on the structure of the seedbed suppression device and its working principles. The discrete element method was adopted for numerical simulation on the suppression process of the seedbed with whole plastic film mulching on double ridges; the parameters during the interaction between the suppression device and seedbed soil were extracted and analyzed, such as contact area, sinkage and horizontal traction resistance trend of press wheels on big ridges and furrows of small ridge. Taking the suppression load on big ridges, suppression load on furrows of small ridge, and advancing velocity of the combined operation machine as the independent variables, qualified rate of suppression as the response value, a mathematical model between the test factors and qualified rate of suppression was established, to explore the influence sequence of the factors on suppression qualified rate. The optimal working parameters of the suppression device were finally obtained: the suppression load on big ridges was 40 N, suppression load on furrows of small ridge was 69.8 N and the machine advancing velocity was 0.98 m/s, and the achieved mean value of suppression qualified rate was 92.6%. Field verification test showed that the mean value of suppression qualified rate was 90.3%, a mere difference of 2.3% compared with the simulation result. The actual operation of the sample machine was basically consistent with the simulation process and could reveal the mechanized suppression operation mechanism of the seedbed with whole plastic film mulching on double ridges, indicating that the established DEM model and its parameter setting were relatively accurate and reasonable. Keywords: seedbed, whole plastic film mulching, double ridges, mechanized suppression, discrete element method, numerical simulation, parameter optimization DOI: 10.25165/j.ijabe.20211401.5866 Citation: Dai F, Song X F, Zhao W Y, Sun B G, Shi R J, Zhang Y. Numerical simulation and analysis of mechanized suppression process of seedbed with whole plastic film mulching on double ridges. Int J Agric & Biol Eng, 2021; 14(1): 142–150.

Desempenho agronômico de rúcula (Eruca sativa L.) em diferentes manejos da cobertura de solo

O presente trabalho teve como objetivo avaliar o desempenho agronômico da rúcula sob diferentes manejos da cobertura de solo. O experimento foi realizado em Florianópolis – SC com delineamento em blocos casualizados, com quatro tratamentos e quatro repetições. Foi utilizada a cultivar Rococó, semeada diretamente em campo em um espaçamento de 5 x 15 cm entre plantas e entre linhas, respectivamente. Os tratamentos consistiram na testemunha (sem capina), cobertura morta, lona plástica e capina manual. Avaliou-se o número de folhas, área foliar e massa fresca. O experimento foi finalizado aos 33 dias após a semeadura. Os dados foram submetidos à análise de variância e ao teste de Tukey para diferenciar as médias a 5% de probabilidade. A capina manual das plantas espontâneas foi significativamente superior à ausência de capina para a área foliar, massa fresca e produtividade. Não houve diferenças entre os tratamentos para o número de folhas. Os resultados demonstraram melhor desempenho da rúcula quando manejada com capina manual, mas os manejos com cobertura morta ou lona plástica apresentaram desempenho similar, também sendo alternativas viáveis.

高强度地膜对盐碱地滴灌棉花生长发育及其产量提升效果研究

高强度地膜对盐碱地滴灌棉花生长发育及其产量提升效果研究

Pengendalian Organisme Pengganggu Tanaman Melalui Solarisasi Tanah

Organisme pengganggu tumbuhan (OPT) seperti hama, patogen, dan gulma menimbulkan masalah dalam budidaya tanaman sehingga perlu upaya penanganan yang tepat. Solarisasi tanah merupakan salah satu alternatif pengendalian OPT tersebut. Makalah ini membahas informasi tentang pengendalian organisme pengganggu tanaman dengan teknologi solarisasi. Beberapa komponen yang berperan dalam proses solarisasi yaitu radiasi matahari sebagai sumber energi, mulsa plastik sebagai pengubah sumber energi, serta lengas tanah sebagai penangkap dan penghantar panas yang dihasilkan plastik pada jeluk tanah yang lebih dalam. Solarisasi tanah bersifat ramah lingkungan dan dilakukan sebelum tanam dengan mengelola energi panas dari radiasi matahari. Solarisasi tanah terbaik yaitu dengan menggunakan lembaran plastik transparan karena bersifat tembus cahaya dimana sebagian besar cahaya ditransmisikan melalui lembaran plastik dan hanya sedikit yang diserap dan dipantulkan. Suhu tanah yang tinggi akibat solarisasi tanah dapat menekan patogen tanah, hama tanah, dan propagul gulma serta dapat meningkatkan kesuburan tanah, pertumbuhan dan hasil tanaman.

Respons Pertumbuhan Bibit Kelapa Sawit Akibat Pengaturan Bobot Mulsa Tandan Kosong dan Frekuensi Penyiraman

Kekurangan air umumnya menjadi faktor pembatas bagi pertumbuhan bibit kelapa sawit di pembibitan utama. Penelitian ini dilakukan untuk menentukan pengaruh mulsa tandan kosong kelapa sawit dan frekuensi penyiraman terhadap pertumbuhan bibit kelapa sawit yang dipelihara di pembibitan utama. Penelitian ini telah dilaksanakan di Unit Pembibitan Kelapa Sawit Politeknik Negeri Lampung mulai April 2019 sampai September 2019, menggunakan rancangan acak kelompok dengan dua faktor dan tiga ulangan. Faktor pertama adalah bobot mulsa (0 g, 100 g, 200 g, and 300 g) dan faktor kedua adalah frekuensi penyiraman (setiap hari, setiap dua hari, dan setiap tiga hari). Hasil penelitian menunjukkan bahwa terdapat interaksi antara bobot mulsa tandan kosong kelapa sawit dan frekuensi penyiraman pada diameter batang, laju transpirasi, dan laju fotosintesis bibit kelapa sawit. Aplikasi mulsa tandan kosong kelapa sawit 200 g dan 300 g yang dikombinasikan dengan frekuensi penyiraman setiap dua hari dan tiga hari mampu menghasilkan diameter batang bibit kelapa sawit yang sama dengan bibit kelapa sawit dengan perlakuan kontrol. Kelembapan tanah yang rendah di sekitar perakaran bibit kelapa sawit menyebabkan fotosintesis dan ketersediaan hara berkurang.

Mechanism analysis and performance improvement of mechanized ridge forming of whole plastic film mulched double ridges

In order to achieve high-performance and mechanization construction standard of whole plastic mulched double ridge seedbed, and to meet its forming process and corresponding agronomic requirements of the mechanized double ridge seedbed, the key working parameters such as the speed of rotary blade group, the thickness of upturned sod and the power consumption of rotary blade group under different parameters were analyzed based on related working performance in ridge forming. Also, the test factors and their range of values were finally determined in this study. Discrete element method (DEM) simulation was applied in the numerical simulation of the mechanized ridge forming process of whole plastic mulched double ridges, and the ridge forming effect and digging resistance variation characteristics of different types of shovels were compared. Taking the forward speed of the combined machine, the penetration angle of the arc-shaped shovel and the depth of rotary tillage as independent variables, and the qualified rate of seedbed tillage as the response value, the mathematical model between the test factors and the qualified rate of the seedbed tillage was established, to explore the influence sequence of the factors on the qualified rate of seedbed tillage, and obtained the following optimal working parameters of the ridge forming device: the advancing velocity of the combined machine of 0.50 m/s, penetration angle of the arc-shaped shovel of 31°, rotary tillage depth of 140 mm, and average qualified rate 95.20% of seedbed tillage in corresponding simulation verification test. Field test showed that the average qualified rate of seedbed tillage in ridge forming device was 93.60%, which was close to that of the simulation results. The actual working condition of the sample machine was basically in line with the simulation process and could relatively precisely reflect the mechanized ridge forming mechanism of whole plastic double ridges. The results showed that the established DEM model and its parameter setting were relatively accurate and reasonable. Keywords: whole plastic film mulched double ridges, mechanized ridge forming, DEM, numerical simulation, parameter optimization DOI: 10.25165/j.ijabe.20201305.5747 Citation: Dai F, Song X F, Zhao W Y, Shi R J, Zhang F W, Zhang X K. Mechanism analysis and performance improvement of mechanized ridge forming of whole plastic film mulched double ridges. Int J Agric & Biol Eng, 2020; 13(5): 107–116.

Cultivo de plantas forrageiras de apelo regional para o Semiárido brasileiro sob a perspectiva de técnicas agrometeorológicas para melhoria da resiliência: uma revisão

A baixa disponibilidade de forragem devido à escassez hídrica e o efeito das mudanças climáticas são problemas enfrentados pelos produtores rurais das regiões semiáridas. Para contornar esses efeitos, pesquisas mostram a importância da utilização de espécies que sejam adaptadas às condições ambientais. Dentre essas espécies, a palma forrageira é um importante alimento para dietas de ruminantes, de alta aceitabilidade, rico em energia e alto teor de água, além da sua implantação no campo ser de baixo custo. O milheto é uma outra espécie usada, pois apresenta tolerância aos estresses hídrico e salino, além de ser um alimento útil para suplementação junto com a palma forrageira. O emprego de práticas agrícolas como irrigação, cobertura morta e consorciação pode auxiliar no sistema de produção dessas culturas. Além disso, a aplicação de parâmetros agrometeorológicos são relevantes para garantir o melhor planejamento e a tomada de decisão agrícola. Nesta revisão, objetivou-se abordar práticas agronômicas, análises estatísticas e indicadores agrometeorológicos empregados em pesquisas voltadas às culturas da palma forrageira e do milheto em sistemas de produção. Pesquisas foram feitas nas bases bibliográficas da Scopus, ScienceDirect, Mendeley e Google Scholar. As práticas agrícolas uso mínimo de irrigação, cobertura morta e consorciação são essenciais nos sistemas de cultivo da palma forrageira e do milheto. Em conjunto ao manejo dessas culturas, o uso de indicadores agrometeorológicos atrelados à análise multivariada permite o melhor planejamento e tomada de decisão na produção.

Influence of nutrient management and moisture conservation practices on Growth and development of organic baby corn (Zea mays L.) in Assam

Background: Baby corn is the small (6-7 cm long) and young unfertilized corn ear harvested at the stage of silk emergence (i.e. within 2 - 3 days of silk emergence). In the present scenario, the use of chemical fertilizers may help in achieving maximum yield of baby corn but they pose serious health hazards and it is a big threat to the sustainability of agriculture. Assam has tremendous potential to grow crops organically and emerge as the main supplier of organic products in the world’s organic market. In Assam, baby corn is rather a new introduction, so efforts are required to standardize the its cultivation. Therefore, the need was felt to standardize organic production technology for baby corn through supplementation of the nutrient requirement through organic manures and biofertilizers. Moisture conservation in agriculture is also very essential in this dynamic climate change. Methods: A field experiment was conducted at Assam Agricultural University, Jorhat during the year 2016-17. The experiment consisted of two different factors i.e. nutrient management viz., control, enriched compost 2.5 t ha-1, vermicompost 2 t ha-1 incubated with bio-fertilizers, poultry manure 2 t ha-1 incubated with bio-fertilizers, FYM 2.5 t ha-1 incubated with bio-fertilizers and FYM 2.5 t ha-1+lime+ash (1000:10:1) and moisture conservation i.e. no mulch and mulch with paddy straw @ 2 t ha-1). Plant height at harvest, number of leaves plant-1 at harvest and dry matter production (g plant-1), LAI, LAD at 30 day days interval was recorded. Reading on chlorophyll content was taken by SPAD- 502 chlorophyll meter at 45 DAS and 90 DAS. Cob yield was recorded from the net plot area and expressed in t ha-1. Result: Application of enriched compost 2.5 t ha-1 in baby corn produced highest growth characters like plant height, number of leaves plant-1, dry matter production, leaf area index, leaf area duration, chlorophyll content, cob yield with husk (8.165 t ha-1) followed by FYM 2.5 t ha-1+lime+ash (6.495 t ha-1). Mulching with paddy straw 2 t ha-1 recorded the higher cob yield (6.172 t ha-1) over no mulch condition (5.431 t ha-1).

Effect of spread and shallow irrigation wetted area and application of organic mulch on citrus decline amelioration

Citrus decline threatens the orchards in the southern part of Iran. Roots begin to die-out before citrus decline deterioration. In this study, the effect of expanding the irrigation wetted area and decreasing the irrigation depth, and application of compost as organic mulch on root development and amelioration of citrus decline in Valencia orange trees (Citrus scinensis L. Osbeck) was investigated. Experimental factors contained the different percentage of irrigation wetted area and decreasing irrigation effective root depth by drip irrigation system at three levels - control (30-40% with 60 cm effective root depth), 50-60% with 45 cm effective root depth and 70-80% with 30 cm effective root depth under tree canopy area and the factor of annual application of compost as organic mulch at two levels - control (without) and application of 80 kg compost under tree canopy area with 10 cm thickness as ground cover, after rotating the top soil at 10 cm depth for all treatments. The results showed that, annual application of compost as organic mulch under tree canopy area and expanding the irrigation wetted area with decreasing irrigation effective root depth, significantly improved fibrous root length and density at a lower soil depth and decreased the indices of citrus decline such as root rot percentage, leaf and fruit drop and shoot die back. Also these treatments increased the water productivity and fruit quality of in declining Valencia orange trees.

Factores que influyen en la erosión hídrica del suelo en un bosque templado

Los ecosistemas forestales son importantes en la aportación de bienes y servicios a la sociedad; sin embargo, pueden estar afectados por erosión hídrica, lo cual representa un problema grave en México. Por lo tanto, el objetivo de este trabajo fue determinar los factores que explican ese tipo de degradación en un bosque templado. Los factores incluidos fueron seleccionados mediante revisión de literatura, a nivel nacional e internacional, con el criterio de uso en programas de manejo y monitoreo. Para evaluar la pérdida por erosión, se utilizó la medición de pedestales. Estadísticamente, se emplearon la correlación de Pearson y el Análisis de Componentes Principales (ACP). Los resultados de la primera evidenciaron que la densidad aparente (r= 0.64), pendiente (r=0.59) y el porcentaje de rocas en la superficie del suelo (r=0.57) tienen correlación positiva con la erosión hídrica; por lo que, al incrementar sus valores, aumenta la presencia de pedestales. Se determinó una correlación negativa con la profundidad (r= -0.48) y el porcentaje de materia orgánica (r= -0.45). A mayor magnitud de estos parámetros, disminuye la presencia de pedestales como expresiones del grado de erosión de los suelos. Mediante el ACP, se obtuvo que, además, incidieron directamente, el espesor del mantillo, la presencia de suelo desnudo y la compactación. También, se identificó una correlación positiva con el porcentaje de suelo desnudo y la compactación. No hubo significancia con la materia orgánica, capacidad de infiltración y profundidad del suelo. Los factores señalados deben considerarse para facilitar los monitoreos futuros.

Degradability of biodegradable plastic films and its mulching effects on soil temperature and maize yield in northeastern China

Plastic film is an important resource in agricultural production, but it takes hundreds of years to degrade completely in natural environment. The large-scale use of plastic film will inevitably lead to serious environmental pollution. One way to solve the problem is to develop a substitutable mulching film, such as a biodegradable film that can ultimately be decomposed to water, carbon dioxide, and soil organic matter by micro-organisms. In this study, a 2-year experiment was conducted to determine the degradation properties of a biodegradable plastic film, including degradation rate, surface microstructure, tensile strength and elongation at break, and the effects of different mulching treatments on soil temperature and maize yield. The mulching experiment was conducted with three different biodegradable plastic films with different degradation rates, using a common plastic film and a non-mulched treatment as control. With the addition of the additives for degradation in the biodegradable plastic films, the degradation rates increased significantly, which were 7.2%-17.8% in 2017 and 18.1%-35.2% in 2018 after maize harvesting. However, the degradation occurred mainly on the ridge side. The decrease in tensile strength and elongation was proportional to the degradation rate of the degradable film. The SEM results indicated that the surface microstructures of the biodegradable films were loose and heterogeneous after maize harvesting. Biodegradable plastic film mulching increased the soil temperature at soil depths of 5 cm, 15 cm, and 25 cm, over the maize’s entire growth period, by 3.1°C-3.2°C in 2017 and 1.2°C-2.1°C in 2018 compared with the non-mulched treatment. The biodegradable plastic film increased the maize yield by 10.4%-14.3% in 2017 and 11.6%-24.7% in 2018. The soil temperature and maize yield increases were statistically significant; however, with respect to maize qualities, there were no statistically significant increases among the five treatments. This study shows that biodegradable plastic film can be used as a substitute for common plastic film. However, the ingredients in biodegradable plastic films should be improved further to ensure that they can be degraded completely after crop harvest. Keywords: biodegradable plastic film, film mulching, degradation properties, soil temperature, maize yield DOI: 10.25165/j.ijabe.20201302.5360 Citation: Zhang W W, Wang L H, Zhou J Q, Zhu K L, Sun S J. Degradability of biodegradable plastic films and its mulching effects on soil temperature and maize yield in northeastern China. Int J Agric & Biol Eng, 2020; 13(2): 146–153.

Root transcriptome reveals responses to plastic film mulching and grass cover in wine grape 'Cabernet Sauvignon' root and berry

This study was designed to investigate the influence of grass and film mulching on grape (V. vinifera) fruit quality and root transcriptome. The groundcovers (plastic film and seeds of herba portulacae and E. humifusa Willd) were set or sawn on the ground under wine grape plants ('Cabernet Sauvignon'). Test plots in the control group were treated with clean tillage. Properties of plant biochemicals under covers and grape berry quality were determined after two years. RNA-seq was analyzed for grape roots under different treatments. E. humifusa Willd cover increased plant total N and P; and film mulching increased plant total P and decreased plant total K. Herba portulacae cover decreased berry tannin and increased anthocyanin, soluble solid and titratable acid; E. humifusa Willd cover increased anthocyanin, soluble solid and titratable acid. Film mulching increased the contents of berry total phenols, soluble solid, and decreased titratable acid significantly in comparison with clean tillage. Root RNA-seq showed that there were 1, 0, and 42 differently expressed genes (DEGs) in Herba portulacae, E. humifusa Willd and film cover, compared with clean tillage, respectively. Film mulching increased the expression of root high-affinity nitrate transporter 2.1 (NRT2.1), NRT2.4 and glutamine synthetase, which associated with 'Nitrogen metabolism', and decreased the expression of root small class I/II heat shock proteins. Plastic film mulching increased grapple quality properties via activating N metabolism. Film mulching was a more excellent mulching for improving grape quality than grass cover in Ningxia, China.