Barley Straw Mulch Research Articles

USING COLORED SHADE NETS AND ORGANIC MULCH TO IMPROVE MICROCLIMATE, GROWTH, AND YIELD OF YELLOW SWEET PEPPER

The study was carried out to investigate the effect of using color shade nets and organic mulch on improvement microclimate, growth, yield, and its components and fruit quality of yellow sweet pepper cv. Yellow Star F1 under high temperature. The study was conducted at El- Arish Agriculture Research Station, Agric. Res. Center, North Sinai Governorate, Egypt, during the summer seasons of 2018 and 2019. The results indicated that application of color shade nets modified microclimate around pepper plants where decreased average monthly of air temperature and light intensity; however, increased air relative humidity compared with unshaded. On the other hand, using black, green, and white shade nets combined with dry vegetable residues mulch followed by barley straw mulch reflected the lowest soil temperature at depths 10 and 20 cm in both growing seasons. Also, the results showed that using green shade nets followed by black shade nets combined with dry vegetable residues or barley straw mulches recorded the highest values for a fresh and dry weight of pepper plant organs. Besides, the highest contents of Chlorophyll b in leaves and vitamin C in fruit juice were obtained when covered by green nets combined with dry vegetable residues mulch in both seasons. Also, results revealed that the interaction between shading of yellow fruit pepper plants by black and green color nets with dry vegetable residues mulch significantly increase average fruit weight and total fruit yield for marketable yield compared to the open field without mulching in the first and second season. For that, it is recommended using of shade color nets (Black and green) with organic mulch (dry vegetable residues mulch and/or barley straw mulch) under high-temperature regions for modifying microclimate conditions of pepper plants and soil to improve growth, productivity, and fruit quality traits.

Cereal Straw Mulching in Strawberry—A Facilitator of Plant Visits by Edaphic Predatory Mites at Night?

In Norway, strawberry producers use cereal straw mulching to prevent berries from contacting the soil and to control weeds. We hypothesized that organic matter such as straw mulch also favors the maintenance of predatory mites which visit strawberry plants at nighttime. We compared mite diversity in cereal straw exposed for different periods in strawberry fields and evaluated their possible migration to plants in two experiments with potted plants in 2019. An ‘Early season’ experiment compared no mulching (T1), oat straw mulch exposed in field since 2018 (T2), or 2017 (T3), while a ‘Mid-season’ experiment compared no mulching (T1), barley straw mulch from 2018 (T2), or a mix from 2017 and 2018 (T3). To provide edaphic predatory mites with a potential source of food, all plants were infested with two-spotted spider mite (Tetranychus urticae Koch). Results suggested that straw mulch facilitates the prevalence of predatory mites in strawberry fields. Most predatory mite visits were at night, confirming our initial hypothesis. Predominant nocturnal mites on leaves belonged to Melicharidae (Proctolaelaps sp.) (‘Early season’, T2), Blattisociidae (Lasioseius sp.) (‘Early and Mid-season’, T3) and Phytoseiidae (‘Mid-season’, T2). Parasitus consanguineus Oudemans & Voigts was the predominant species (‘Early season’, T3) at the base of plants. Anystidae were diurnal visitors only (‘Mid-season’, T2). Future studies should evaluate the predation potential of Proctolaelaps sp. and Lasioseius sp. on two-spotted spider mite and other strawberry pests.

The immediate effectiveness of barley straw mulch in reducing soil erodibility and surface runoff generation in Mediterranean vineyards

Soil and water loss in agriculture is a major problem throughout the world, and especially in Mediterranean areas. Non-conservation agricultural practices have further aggravated the situation, especially in vineyards, which are affected by one of the highest rates of soil loss among cultivated lands. Therefore, it is necessary to find the right soil practices for more sustainable viticulture. In this regard, straw mulching has proven to be effective in other crop and fire affected soils, but, nonetheless, little research has been carried out in vineyards. This research tests the effect of barley straw mulching on soil erosion and surface runoff on vineyards in Eastern Spain where the soil and water losses are non-sustainable. An experiment was setup using rainfall simulation tests at 55mmh−1 over 1h on forty paired plots of 0.24m2: twenty bare and twenty straw covered. Straw cover varied from 48 to 90% with a median value of 59% as a result of the application of 75g of straw per m2. The use of straw mulch resulted in delayed ponding and runoff generation and, as a consequence, the median water loss decreased from 52.59 to 39.27% of the total rainfall. The straw cover reduced the median sediment concentration in runoff from 9.8 to 3.0gL−1 and the median total sediment detached from 70.34 to 15.62g per experiment. The median soil erosion rate decreased from 2.81 to 0.63Mgha−1h−1 due to the straw mulch protection. Straw mulch is very effective in reducing soil erodibility and surface runoff, and this benefit was achieved immediately after the application of the straw.

Effect of mulching on weed infestation and yield of beetroot (Beta vulgaris ssp. rapaceae atrorubra Krass)

Weed infestation in a field with beetroots can reduce the yield because the weeds compete with the cultivated plants for nutrition, water and light and depress their growth. The aim of this field experiment was to study the effect of two different organic mulches on weed infestation and yield of beetroot: barley straw mulch (BSM) and mulch from spent mushroom compost (SMCM). They were compared with two control variants: non-mulched but weeded control plot (WC) and non-mulched and non-weeded control plot (NWC). The field experiment was carried out in the experimental field of the University of Forestry, Sofia, for 2 years’ period. The mulching materials were spread manually in a 5-cm thick layer, at the 3-rd leaf growing stage of beetroot. On the 60th day after mulching, the number of weeds on each plot was recorded. It was found out that mulching with BSM and SMCM has a significant weed reducing effect, especially on cockspur (Echinochloa crus-galli L.), red finger-grass (Digitaria sanguinalis (L.) Scop.), common amaranth (Amaranthus retroflexus L) and gallant soldier (Galinsoga parviflora Cav). The yields increased 8–10 times when beetroot was grown with mulches, compared with NWC. In comparison with WC, the beetroot yield was higher by 7.8–9.3 % on the plots mulched with BSM during the 2 years of the experiment; the plots mulched with SMCM showed a yield increase of 22.8 % but only for the first year. Statistical analyses were performed by using the ANOVA. Significant differences between treatments were assessed using Tukey’s test at P = 0.05.

Cover crops and mulches influence weed management and weed flora composition in strip‐tilled tomato (Solanum lycopersicum)

SummaryThis study was conducted in the Mediterranean environment of Central Italy from 2011 to 2013 with the aim of evaluating the effects of winter cover crops and their residues on weed composition in a cover crop‐tomato sequence. Treatments consisted of five soil managements (three cover crop species ‐ hairy vetch, phacelia, white mustard, winter fallow mulched with barley straw before tomato transplanting and conventionally tilled soil), two nitrogen fertilisation levels (0 and 100 kg N ha−1) and two weed management levels (weed free and weedy) on tomato. Cover crop residues were arranged in strips on the soil surface and then used as beds for transplanting the tomato seedlings in paired rows. Rotary hoeing was performed in the bare strips between paired tomato rows. At tomato harvesting, the weed aboveground biomass and density was higher in nitrogen‐fertilised tomato than unfertilised tomato, except in hairy vetch and barley straw that showed similar values. Hairy vetch used as a cover crop and dead mulch was the most suppressive species with the highest production of residues, while phacelia and mustard were not suitable for controlling weeds. The tomato yield was high in nitrogen fertilised and weed‐free treatments, except in barley straw mulch, which showed similar values among the weed management treatments. The mulch strips caused variations in weed species composition that was mainly composed of perennial ruderal weeds, while in tilled soil, the weed flora was dominated by annual photoblastic weeds.

Organic mulching, irrigation and fertilization affect soil CO2 emission and C storage in tomato crop in the Mediterranean environment

Carbon stock and CO2 emissions in agricultural systems are highly affected by the management of applied practices in arable farms, such as fertilizer use, irrigation, soil tillage, cover crop management, etc. This study evaluated the effects of various organic mulches, nitrogen fertilization and irrigation levels on soil CO2 emissions, soil carbon sequestration and processing tomato production in the Mediterranean environment. The field experiment was carried out with five main treatments, three cover crops of hairy vetch (HV), lacy phacelia (LF) and white mustard (WM) transplanted in autumn and cut in May to be used as mulches, plus barley straw mulch (BS) and conventional (C) (bare soil). After tomato transplanting, the main plots were split into two nitrogen fertilization treatments (0 and 100kgNha−1) and the sub-plots were then split again into three irrigation levels (irrigation water 100%, 75%, 50% of evapotranspiration). In all treatments, a general effect was observed in the temporal fluctuations of soil CO2 emissions throughout the observation period which were significantly influenced by soil temperature and water content. The temporal fluctuations of the soil CO2 emissions were attributed to climatic conditions and the peaks achieved optimal conditions of soil temperature and water content for soil respiration. A larger amount of TOC was observed in the mulching treatments than in the control after tomato harvesting (on average 1.44% vs 1.33%, respectively and on average 1.43% in HV trastment), probably due to the residual biomass of the cover crops and a greater growth of the tomato. Although the soil carbon output as cumulated CO2 emissions did not show statistically significant differences between the treatments, the soil carbon balance enabled us to estimate the highest net carbon contribution to the soil in HV determined by inputs and input/output ratio. However, except for the BS in 2013, the input/output ratios were >1 in all mulch treatments. In the Mediterranean environment, agronomical practices, such as the use of hairy vetch mulch on notilled soil, a slight reduction of irrigation water (−25%) and a rationalized use of N fertilizer potentially could shift the C balance in favor of soil C accumulation.

English

  A field experiment was conducted under natural rainfall conditions to investigate the effects of farmyard manure and straw mulch on runoff, soil loss, in-situ water conservation, and the yield and yield components of an improved bread wheat variety (HAR-1480) grown on vertisol of Sinana area, south eastern Ethiopian highland. The experimental design used was randomized complete block design (RCBD) with seven treatments involving three levels of farmyard manure (2, 4 and 6 ton ha-1), three levels of barley straw mulch (2, 4 and 6 ton ha-1), and a control without manure and mulch that were replicated three times. The results revealed that there was a highly significant difference (P<0.0001) between the treatments regarding their effect on runoff depth, soil loss and in-situ water conservation. However, there was no significant difference in grain yield due to the treatments. Moreover, compared to straw mulch, manuring was found to be less effective in reducing runoff and soil loss in the first season of application. Additionally, the soil loss measured for all strawmulch rates were not significantly different, implying that the 2 ton ha-1 mulching rate can effectively check soil erosion under the existing slope and rainfall conditions of the study area.   Key words: Bale highland, runoff depth, soil conservation, grain yield, sediment concentration.

Does mulching influence potential predators of raspberry beetle?

The effect of different mulches on carabid abundance and species composition was studied using pitfall traps in the Polli experimental raspberry plantation in the years 2001–2003 and 2006. Experimental treatments compared were: control – soil with no mulch and different mulch treatments – birch sawdust, milled peat, barley straw and black plastic. To estimate the potential role of carabids in raspberry beetle population regulation, the population dynamics of the dominant carabid species in relation to raspberry phenophases was determined. The activity density and species richness of carabids increased with plantation age and were influenced by mulching. In all study years, at the time of ripening of the raspberry fruits, when the raspberry beetle larvae leave the fruits to pupate in the soil, the most dominant carabid species were: Pterostichus vulgaris, Pterostichus niger, Carabus nemoralis and Harpalus pubescens. The barley straw mulch was significantly preferred to the other mulches by P. niger, P. vulgaris and C. nemoralis. H. pubescens did not exhibit a preference for a particular mulch. These four carabid species could be potential key predators of raspberry beetle larvae in Nordic plantations of perennial raspberry.

اثر آفتابدهی و مالچ کاه جو بر تراکم و زیست توده علفهای هرز

Today, due to the problems caused by herbicide application, there is a strong interest in developing alternative methods of weed control. To study the effects of soil solarization, barley straw mulch on weed flora, a field experiment was conducted at Research station of faculty of Agriculture, Ferdowsi University of Mashhad during the growing season of 2007-2008. This experiment was based on a randomized complete block design arranged as a split plot with three replications. Soil solarization treatment (Clear and black polyethylene and non-solarized control) and various straw mulch rates (0, 300 and 600 gm-2) were arranged on the main plots and sub plots, respectively. Seventeen weed species was identified by studying weed population which were mainly annual broad-leaves species. Results indicated that solarization with clear and black sheets reduced weed density and biomass after removing polyethylene sheets. Solarization with clear sheets reduced weed density and biomass, after application of straw mulch. Straw mulch had no significant effect on weed density, but in last sampling date it reduced biomass up to 44.15% and 52.90% in 300 and 600 gm-2, respectively. The interaction effects of solarization and straw mulch on weed biomass was significant but only at 90 days after application of straw mulch. The lowest weed biomass observed in solarized bared plots with applying clear sheets.

Simulating the radiation distribution within a barley-straw mulch

Mulching is a technique widely used to moderate soil microclimate. Modelling radiation transfer within mulches is a critical step in the development of comprehensive microclimate models of the soil–mulch–atmosphere system and similar hay-drying systems. The objective of this research was to develop a relatively simple physically-based model that predicts profiles of shortwave and longwave radiation flux densities within barley-straw mulches and to test it against hourly radiation flux measurements made above and below mulches applied at rates of 2, 5, 10, and 15 t ha −1 in successive field-plot experiments. Unique features of the model include accounting for upper-surface and lower-surface mulch element temperatures using effective view factors and neglecting all shortwave reflections beyond secondary ones, so that calculation of the fluxes above any layer is explicit and does not require matrix inversion. Model input parameters were for the most part measured completely independently of the field tests. Measured transmissivities demonstrated that mulch elements were uniformly distributed, as expected, for low mulch application rates but were clumped for higher rates, which was attributed to the greater effort then needed to separate the elements of baled straw. Sensitivity tests showed that solar irradiance, atmospheric emissivity, and mulch element reflectivity are important input parameters to the model and that measuring the difference between upper-surface and lower-surface mulch element temperatures is not as critical. Modelled and measured net radiation flux density above the mulch and total downward radiation flux density near the bottom of the mulch were generally in excellent agreement, with some exceptions. These were attributed mainly to measurement error (condensation on the upper dome of the net radiometer above the mulch before and just after sunrise and inadequate spatial averaging under the thin mulches). Modelled profiles of daytime and nighttime radiation fluxes in a 10 t ha −1 mulch and simulations of the effects of uniformity, randomness, and clumping of mulch elements are reported.

Turbulent exchange processes within and above a straw mulch.: Part II: Thermal and moisture regimes

This paper, the second of a two-part series, reports on measurements of thermal and moisture regimes, including sensible and latent heat flux densities, and the complete energy balance made above and within a 10 t ha −1 (6.6 cm high) barley-straw mulch in both normal and artificially wetted states. Soil, mulch, and air temperatures were measured with fine-wire thermocouples, the sensible heat flux was determined with an air renewal model from the cubic structure function of measured air temperature fluctuations, water-vapour pressures were measured within and above the mulch with capacitance sensors, the (energy-limited) latent heat flux below the mulch was measured with a custom-made tension-plate system and latent heat fluxes at heights above the soil surface were determined from additional measurements of weight loss or gain of the mulch elements, net radiation flux was measured above the mulch and downcoming radiation measured below the mulch with thermopile radiometers, soil heat flux was determined with a custom-made thermopile plate installed at the 1 cm depth and corrected for heat storage in the soil above the plate, and heat storage within the mulch was determined from measured mulch element temperatures. During daytime on fine summer days, the source of the most of the sensible heat flux is in the upper third of the mulch, which corresponds to where the upper-surface mulch element temperature exceeds air temperature. Sensible heat is transferred counter to the local vertical gradient near the middle of the mulch, which puts a lower limit of about 2 cm on the size of the eddies responsible for most of the transfer. Near the bottom of the mulch, the sensible heat flux is small and directed downward, in accordance with the strong air temperature inversion within the mulch. The largest source of latent heat during daytime is from the underlying soil surface except early in the morning when evaporation of dew near the top of the mulch dominates. Turbulence within the mulch enhances latent heat transfer above that due to molecular diffusion by 2–6 times, with mild dependence on wind speed. During nighttime, sensible heat flux within the mulch was small but latent heat flux was a large component in the energy balance, which was attributed in part to the unstable conditions that then existed within the mulch. The sum of sensible, latent, soil, and storage heat fluxes (all measured independently) at all heights within and above the mulch are in good agreement with net radiation flux determined using a radiation transfer model developed for the mulch under normal (non-wetted) conditions. The largest effect of artificially wetting the mulch was on latent heat flux below the mulch which became negative, indicating condensation, during daytime. For the data after the irrigation, net radiation flux from the radiation transfer model is no longer in good agreement with the sum of sensible, latent, soil, and storage heat fluxes near the bottom of the mulch. Agreement was considerably improved by increasing the residue area, mostly in the lower part of the mulch, which is consistent with the irrigation causing brittle pieces of mulch to break off and fall towards the soil surface.

Turbulent exchange processes within and above a straw mulch.: Part I: Mean wind speed and turbulent statistics

Mulching is a technique widely used to conserve soil and moderate its microclimate. Modelling transfer processes in mulches is limited by our lack of understanding of turbulent exchange within the mulch. This paper, the first of a two-part series, reports on measurements of wind and turbulence made above and within a 10 t ha −1 barley-straw mulch using custom-made hot-wires and a tri-axial hot-film probe. Wind regimes within the mulch during daytime (relatively high wind) and nighttime (low wind) differ greatly. During daytime, 10 min average horizontal wind speeds at all levels in the mulch (where they vary nearly exponentially with height) correlate well with (near-logarithmic profile) wind speeds above the mulch and are not affected by the strong temperature inversion existing in the mulch. During nighttime, 10 min average horizontal wind speeds within the mulch are decoupled from (poorly correlated with) wind speeds in the generally stable air above the mulch. Unstable conditions in the mulch at night lead to free convection, which explains the good correlation of 10 min average wind speeds at all heights within the mulch and the high evaporation rates we measured below the mulch. Under high wind conditions most of the drag occurs very near the top of the mulch which behaves as an aerodynamically smooth surface similar to a bare soil. Turbulence within the mulch is of high intensity and is dominated by intermittant gusts, with the extreme values described by a Gumbel distribution. The frequency of the gusts agrees reasonably well with that found for laboratory mixing layers. The wind and turbulence regimes in the mulch resemble in many ways those in plant canopies much larger in height and lower in leaf area density.