Effects of Mulching on Soil Water Content, Maize Performance and Weed Growth in Dry Land Area of Bangladesh

Aims: The objectives of the research work were to evaluate the effects of mulching on soil water content, maize performance and weed growth in dry land area of Bangladesh Study Design: The experiment was laid out in a randomized complete block design (RCBD) with three replications Place and Duration of Study: Central research field of Sher-e-Bangla Agricultural University, Dhaka-1207 during November 2019 to April 2020. Methodology: The experimental field is divided into 3 blocks to represent 3 replications. There are 6 unit plots (each unit plot consists of 3m � 2m area) in the experimental farm. Distances of 1 m and 0.5 m are maintained between replication to replication and plots to plots, respectively. Plant to plant and row to row distances are considered to be 0.25 m and 0.75 m, respectively. The treatments are assigned in random plots. The land is ploughed four times followed by laddering to have fine tilth of the soil. The maize cultivars Shuvra and KS-510 are used as plant materials. Fig. 1 represents the six mulch treatments are imposed on the plants: Control (without mulch, CK), water hyacinth dry (10 t/ha, WH), rice straw dry (10 t/ha, RS), black polythene (4m � 3m, BP), white polythene (4m � 3m, WP), and transparent polythene (4m � 3m, TP) (S2). The mulches are applied as per treatment in each plot just after sowing to maintaining an equal thickness throughout the plot. Dried and cleaned mulches are used before applying to the experiment. The significance of the difference among the treatment means were estimated by the MSTAT-C package programme at 5% level of probability. Results: It is found in the experimental results that the soil water content of the no-mulching treatment is lower as compared to that of the other treatments from 0-10 cm, 10-20 cm and 20-30 cm soil depths. It is also observed that the RS mulching provides the highest soil water content, leaf area index (LAI), chlorophyll contents, and total biomass. Significant enhancement of maize yield (20.55 ton/ha) is recorded for the rice straw mulching. In contrast, the weed dry weight of 7.45g/m2 is observed in the RS mulching, which is lower than the other treatments. Conclusions: Therefore, it can be concluded that the RS mulching, compared to other mulching, would be more efficient for maximum utilization of limited water resources, weed suppression as well as to increase the maize yield. The present research approach would be applicable to manage the soil water for enhancing the maize production in dry land area.

Influência do substrato de pó de coco na lixiviação de água residuária / Influence of coconut powder substrate on leaching of wastewater

RESUMO Nas últimas décadas, têm-se observado o crescimento da demanda de água e o agravamento dos cenários de escassez hídrica, bem como a ampliação de alternativas de reuso de água de efluentes de qualidade inferior, em particular de esgotos domésticos tratados. Objetivou-se, com este trabalho, avaliar a influência do substrato de pó de coco no controle de transporte de solutos em solos irrigados com esgoto tratado doméstico. A água residuária doméstica tratada provém da Unidade Experimental de Tratamento e Reúso Hidroagrícola, no distrito de Mutuca-PE. O delineamento experimental foi em esquema fatorial (2 × 3), cujos fatores avaliados compreenderam dois tipos de solos típicos da região (Neossolo Litólico e Argissolo Amarelo) e três tratamentos (sem pó de coco, 1 cm de pó de coco e 2 cm de pó de coco), com cinco repetições. Os parâmetros de transporte dos íons sódio e potássio foram obtidos por ajuste numérico, utilizando-se o modelo STANMOD. Constatou-se a existência de interação com soluto, sódio e potássio, em solo arenoso. O modelo STANMOD apresentou ótimo desempenho na simulação do transporte de solutos no solo. A cobertura de pó de coco mostrou-se eficiente na diminuição da lixiviação de íons em ambos os solos estudados.

ABSTRACT In the last decades, there has been an increase in the demand for water and the aggravation of water scarcity scenarios, as well as the expansion of water reuse alternatives for lower quality effluents, in particular treated domestic sewage. The objective of this study was to evaluate the influence of coconut powder substrate on the control of solute transport in irrigated soils with treated sewage reuse. The treated domestic wastewater comes from the Experimental Unit for Treatment and Agricultural Reuse in the district of Mutuca, Pernambuco. The experimental design was in a factorial scheme (2 × 3), whose evaluated factors comprised two types of soils typical of the region (Leptosols and Yellow Argisol) and three treatments (no coconut powder, 1 cm coconut powder, and 2 cm coconut powder) with five replicates. The transport parameters of the sodium and potassium ions were obtained by numerical adjustment using the STANMOD model. It was found the existence of interaction with solute, sodium, and potassium in sandy soil. The STANMOD model presented excellent performance in the simulation of solute transport in the soil. Soil coverage with coconut powder was shown to be efficient in reducing leaching of ions in both studied soils.

Uso de coberturas alternativas do solo para o controle das perdas de solo em regiões semiáridas / Use of alternative soil covers for the control of soil loss in semiarid regions

RESUMO A região semiárida do nordeste brasileiro é marcada por elevadas incertezas quanto à ocorrência de chuvas intensas, bem como por anos sequenciados de secas. Esses fenômenos naturais, somados à reduzida utilização de práticas conservacionistas, podem gerar degradação dos solos. Nesse contexto, o presente estudo objetivou avaliar a importância do uso de cobertura morta e espécies de oleaginosas não convencionais perenes (Moringa oleifera Lam. e Azadirachta indica A. Juss.) no controle da erosão do solo em parcelas de erosão, em condições de chuvas naturais. O estudo realizou-se durante os anos de 2016 e 2017 na bacia representativa do Mimoso, localizada no município de Pesqueira (PE), Brasil. Na área de estudo, instalaram-se três parcelas de erosão, cada uma com área igual a 40 m2 (2 × 20 m), que foram intensamente monitoradas no tocante à intensidade de precipitação, à umidade e à temperatura do solo, ao escoamento superficial e à produção de sedimentos. Para cada parcela experimental, adotaram-se os seguintes tratamentos: oleaginosas; oleaginosas + cobertura morta; solo descoberto. A cobertura do solo com oleaginosas e cobertura morta resultou em maior retenção de umidade do solo e menores valores de escoamento superficial e perdas de solo. O desenvolvimento da estrutura das oleaginosas diminuiu o impacto direto das gotas de chuva no solo, reduzindo as perdas de solo quando comparadas ao descoberto.

ABSTRACT The semiarid region of the Brazilian Northeast is marked by strong uncertainties regarding the occurrence of extreme rainfall, as well as the occurrence of sequenced year droughts. These natural phenomena, together with limited use of soil and water conservation practices, can generate soil degradation. In this context, the present study aimed to evaluate the importance of the use of mulch and non-conventional perennial oleaginous species (Moringa oleifera Lam. and Azadirachta indica A. Juss.) in soil erosion plots under natural rainfall. The study was conducted during the years of 2016 and 2017 in the representative basin of Mimoso, located in the municipality of Pesqueira, Pernambuco, Brazil. Three erosion plots each with an area of 40 m2 (2 m × 20 m), were installed in the study area, which were intensively monitored for rainfall intensity, soil moisture and temperature, runoff and sediment production. For each experimental plot, the following treatments were adopted: Oleaginous; Oleaginous + mulch; Bare soil. Soil cover with oleaginous species and mulch resulted in higher soil moisture and lower amounts of runoff and soil loss. The development of the tree structure of the oleaginous reduced the direct impact of raindrops on the soil surface, reducing the soil losses when compared to the bare soil.

Rendimento de massa de adubos verdes e o impacto na fertilidade do solo em sucessão de cultivos orgânicos / Mass yield of green manure and impact on soil fertility in succession of organic crops

O objetivo deste trabalho foi avaliar a produção de massa, teores e aporte foliares de adubos verdes, utilizados em região de altitude do Espírito Santo, adequados à implantação da prática de plantio direto de hortaliças sob manejo orgânico. Objetivou-se também avaliar a evolução da fertilidade do solo em decorrência de dois pré-cultivos de milho e crotalária (fevereiro 2009 e outubro 2009) e dois pré-cultivos de aveia preta e tremoço branco (julho de 2010 e maio de 2011). Este trabalho foi desenvolvido na Unidade de Referência em Agroecologia do INCAPER, em Domingos Martins-ES. Os tratamentos consistiram de uma testemunha (sem palhada) e três sistemas de produção de palhadas: 1) cultivo solteiro de gramíneas (milho ou aveia preta); 2) cultivo solteiro de leguminosas (crotalária ou tremoço branco) e 3) cultivo consorciado de gramíneas/leguminosas (milho/crotalária ou aveia/tremoço). Em fevereiro de 2009, a produção de massa verde do sistema milho e milho/crotalária atingiram 73,6 e 64,5 t ha-1, respectivamente. Em julho de 2010, a produção de massa verde nos sistemas tremoço e consórcio aveia/tremoço atingiram 76,3 e 88,3 t ha-1, respectivamente. Os adubos verdes em consórcio comprovaram ser excelente opção de manejo para sistemas orgânicos, por aportarem ao solo 811,4; 941,2; 263,5; 78,6; 51,9 kg ha-1 de N, K, Ca, Mg e S, respectivamente, valores estes iguais ou superiores aos pré-cultivos solteiros. Os efeitos dos pré-cultivos de adubos verdes sobre os atributos químicos do solo em manejo orgânico, excetuando-se o aporte de nitrogênio, foram semelhantes à testemunha em todas as épocas, possivelmente nivelados pela adubação de base com composto orgânico em todos os tratamentos, que mantém altos índices de fertilidade da área.

The aim of this study was to evaluate mass production, nutrient contents and input of green manures used in the altitude region of Espírito Santo to the implementation of appropriate practice no tillage vegetables under organic management. This study also aimed evaluate the evolution of soil fertility as a consequence of two pre-crop maize and crotalária (February 2009 and October 2009) and two pre-crop oat and white lupine (July 2010 and May 2011). The experiments were carried in the INCAPER's Agroecology Reference Area at Domingos Martins-ES. Treatments consisted of a control (no straw) and three straw production systems: 1) cropping of grasses (oats or corn), 2) cropping legume (crotalária or white lupine) and 3) intercropping of grasses/legumes (corn/crotalária or oat/lupine). In February 2009, the production of green mass system corn and corn/crotalária reached 73.6 and 64.5 t ha-1, respectively. In July 2010, the production of green mass systems lupine and oat/Lupin reached 76.3 and 88.3 t ha-1, respectively. The green manures intercropping proved to be excellent management option for organic systems, because added 811.4; 941.2; 263.5; 78.6; 51.9 kg ha-1 of N, K, Ca, Mg and S, respectively, values those at or above the single pre-cultivation. The effects of pre-cultivation of green manure on soil chemical properties in organic management, except for the contribution of nitrogen, were similar to control in all seasons, because of the base fertilization with organic compost in all treatments, maintaining high fertility rates in the area.

Effect of fertilisation and harvest period on polar metabolites of Calendula oficcinalis

The present study evaluated the chemical profile of polar extracts of Calendula officinalis L., Asteraceae, that were grown under different cultivation conditions: chemical fertilisation, organic fertilisation and mulching. Furthermore, we investigated metabolite variations during plant development by comparing the metabolites from harvested plants at 60 and 120 days after planting. We used HPLC-DAD-MS/MS to tentatively identify metabolites. In total, we identified seven known compounds: five flavonoid glycosides and two caffeoylquinic acids derivatives. There were no statistically significant differences in the expression of metabolites from plants grown under the examined soil treatments. However, five substances varied according to harvest time, suggesting that the biosynthesis of polar metabolites of Calendula officinalis is not affected by changes in soil composition. Therefore, this plant could represent a source for phytomedicines with a constant content of polar metabolites.

Controle de plantas invasoras em cultivo orgânico e convencional de capim-limão (Cymbopogon citratus (DC) Stapf. ) / Weed control in organic and conventional crops of lemongrass

O cultivo orgânico é preconizado para o capim-limão (Cymbopogon citratus (DC) Stapf.) como planta medicinal promissora ao desenvolvimento de fármacos no Brasil. Objetivou-se avaliar técnicas de controle de plantas invasoras sobre componentes de produção de capim limão em cultivos orgânico e convencional. Dois experimentos foram instalados sob delineamento inteiramente casualizado, com quatro repetições, em esquema fatorial 2x2x3, considerando-se duas áreas (orgânico e convencional) e os tratamentos combinando cobertura morta (presente e ausente) e técnicas de controle de plantas invasoras (capina manual, roçada e nenhuma). Altura, perfilhamento, teor e rendimento total de óleo essencial de capim-limão no cultivo orgânico foram superiores ao convencional, mas a produtividade de biomassa aérea seca não diferiu entre ambos. A capina, com ou sem cobertura morta, favoreceu o rendimento de óleo no cultivo orgânico.

Organic farming is recommended for lemongrass as a promising medicinal plant for drug development in Brazil. The purpose of this paper was to evaluate the effect of the techniques to control weed on the plant height, tillering, biomass productivity, content and yield of the essential oil of lemon grass in organic and conventional crops. Two experiments were set in a completely randomized design with four replications, at a 2x2x3 factorial scheme, considering two areas (organic and conventional) and treatments combining mulching (present and absent) and weed control techniques (hoeing, skimming and none). Plant height, tillering, content and yield of the essential oil of lemongrass were better in the organic crop, but the biomass productivity did not differ between both areas. The biomass production was better in the conventional crop as to weed control, with or without mulching, and for organic crop under hoeing or skimming with mulching. Hoeing or skimming with no mulching improved the oil content in organic crops. Hoeing or skimming with mulching was better than any other weed control technique with no mulching, and hoeing was better than skimming, justifying its recommendation as a technique for this crop system.

Microbial activity in soil cultivated with different summer legumes in coffee crop

A field experiment was conducted for ten years in a sandy soil in the north part of the Paraná State, Brazil. The soil samples were collected at 0-10 cm depth, both under the coffee canopy and in the inter row space between the coffee plants, in the following treatments: Control, Leucaena leucocephala, Crotalaria spectabilis, Crotalaria breviflora, Mucuna pruriens, Mucuna deeringiana, Arachis hypogaea and Vigna unguiculata. The legume crops influenced the microbial activity, both under the coffee canopy and in the inter row space. The cultivation of Leucaena leucocephala increased the microbial biomass C, N and P. Although L. leucocephala and Arachis hypogaea provided higher microbial biomass, the qCO2 decreased by up to 50 percent under the coffee canopy and by about 25 percent in the inter row space. The soil microbial biomass was enriched in N and P due to green manure residue addition.

Influência da adubação e da cobertura morta na produtividade e no teor de flavonóides de Calendula officinalis L. (Asteraceae) / Influence of fertilization and mulching on the productivity and flavonoid content of Calendula officinalis L. (Asteraceae)

Desenvolveu-se ensaio de cultivo de Calendula officinalis, variando-se os tipos de adubação e utilização de cobertura morta na observação da produção de inflorescências, droga vegetal e quantificação dos flavonóides presentes nestes materiais.O delineamento experimental adotado foi de blocos casualizados com 3 repetições, em arranjo fatorial de 3 x 2, constituído de seis tratamentos, sendo 1. adubação química (100 kg de N ha-1 + 50 kg de P ha-1); 2. adubação química + cobertura morta (grama seca - Paspalum notatum); 3. adubação orgânica (esterco bovino curtido 50 t ha-1); 4. adubação orgânica + cobertura morta; 5. sem adubação química ou orgânica + cobertura morta; 6. sem adubação química ou orgânica e sem cobertura morta (testemunha). Os resultados de número capítulos produzidos, massa seca das inflorescências e massa da droga vegetal foram totalizados após cinco meses do plantio. A quantificação de flavonóides foi realizada através de método espectrofotométrico. Os dados foram analisados estatisticamente (ANOVA/Teste Tukey-Kramer-5 por cento) e mostraram diferenças significativas (70 por cento superior) no número de inflorescências, massa seca das inflorescências e massa da droga vegetal entre o tratamento com adubação orgânica (3) e os tratamentos sem adubação química ou orgânica com cobertura morta (5) e o testemunha (6). As demais comparações, inclusive o teor de flavonóides, entre os diversos tratamentos não resultaram em diferenças significativas.

Calendula officinalis was experimentally grown under field conditions with different fertilization types and mulching in order to evaluate inflorescence production, plant drugs and flavonoid levels. Experimental design was in randomized blocks, with 3 replicates, in a 3x2 factorial arrangement, consisting of six treatments, as follows: 1. chemical fertilization (100 kg N ha-1 + 50 kg P ha-1); 2. chemical fertilization + mulch (dry grass - Paspalum notatum); 3. organic fertilization (cured bovine manure 50 t ha-1); 4. organic fertilization + mulch; 5. no chemical or organic fertilization + mulch; 6. no chemical or organic fertilization and no mulch (control). Data regarding number of produced capitula, dry matter of inflorescences and plant drug matter were totaled after five months of planting. Flavonoids were quantified by spectrophotometry. The results were statistically analyzed (ANOVA / Tukey-Kramer test-5 percent) and showed significant differences (70 percent higher) for number of inflorescences, inflorescence dry matter and plant drug matter between the treatment with organic fertilization (3) and treatments with no chemical or organic fertilization with mulching (5) and control (6). The remaining comparisons, including flavonoid content, did not result in significant differences among treatments.

Coeficiente de cultura do meloeiro irrigado com água salina estimado por modelo matemático / Crop coefficient of muskmelon irrigated with saline water estimated by mathematical model

O coeficiente de cultura (Kc) do melão é importante para estimar a necessidade de água e para manejar eficientemente a irrigação. Com este trabalho objetivou-se avaliar um modelo matemático para estimar o Kc do meloeiro, em função dos dias após o plantio. O modelo matemático avaliado estimou, satisfatoriamente, os valores do coeficiente de cultura, porém as épocas de maior Kc não variaram com os tratamentos, mas alteraram os valores de Kc máximo e a taxa de crescimento absoluta máxima. Verificou-se também correlação positiva entre a época de Kc máximo com os valores de Kc máximo, a época da taxa de crescimento absoluta máxima e com a taxa de crescimento absoluta máxima, como também entre os valores de Kc máximo com a época de taxa de crescimento absoluto máximo e com a taxa de crescimento máxima, assim como entre a época da taxa de crescimento máxima e a taxa de crescimento absoluta máxima.

The crop coefficient is necessary for estimating the water requirement in irrigation planning and management. This work aimed to evaluate a mathematical model to predict crop coefficient versus days after planting. The model provides a quite good performance in estimating the crop coefficient. The time in that maximum Kc occurred didn't vary with the treatments. However there had been alterations in values of maximum Kc and maximum absolute growth rate. Positive correlation was observed between the time for Kc maximum and Kc maximum, between time of maximum absolute growth rate and maximum absolute growth rate, as well as between Kc maximum and time of maximum absolute growth rate and maximum absolute growth rate, and between time of maximum absolute growth and maximum absolute growth rate.

Studies on the Effect of Vinyl Mulching on Pleurotus Cultivation: Control of Mushroom Diseases on Pleurotus ostreatus (II)

Perforated vinyl mulching technique was performed on oyster mushroom beds for controlling mushroom diseases. Mycelium under vinyl sheets were safely protected from outside undesirable microorganisms. One of two mushroom farms showed 75% of disease incidence, the other 40% and National Institute of Agricultural Science and Technology (NIAST) 13% in the conventional growing method, whereas 12%, 14%, and 5% in the vinyl mulching cultivation method. Waterlogging caused mushroom bed worse, and Trichoderma spp. were infested on the conventional mushroom bed. Disease incidence investigated in other case was 25% to 30% in the conventional growing method, whereas 5 to 9% in the vinyl mulching cultivation method. Yields in conventional method were 6.5 to 7.2 kg/m2 and those in vinyl mulching method were 7.6 to 8.1 kg/m2. So it was suggested that vinyl mulching technique was good for prevention from disease and elevation of productivity.

Studies on the Effect of Vinyl Mulching on Pleurotus Cultivation: Bunch Formation on Pleurotus sajor-caju (III)

Perforated vinyl mulching technique was performed on Pleurotus sajor-caju beds to assess fruitbody formation. Individual fruitbody of P. sajor-caju was transformed into bunch type on vinyl mulching bed. It was effective to grow the mushroom without waterlogging and abortion of small pins on the beds as well as hygienical bed management. A bunch showed 79 fruitbodies and 225 g of weight. Available site for fruiting was reduced up to 20% in comparison of 100% for conventional bed. The color of fruitbody turned on brownish white from treated vinyl mulching bed.