Orchard Floor Research Articles

Effects of Floor Vegetation and Fertility Management on Weed Biomass and Diversity in Organic Peach Orchards

Treerow vegetation abundance and biodiversity were measured in response to six orchard floor management strategies in organic peach in northern Utah for three growing seasons. A total of 32 weed species were observed in the treerow; the most common were field bindweed, dandelion, perennial grasses (e.g., red fescue and ryegrass), clovers, and prickly lettuce. Weed biomass was two to five times greater in unmanaged (living mulch) than in manipulated treatments. Tillage greatly reduced weeds for approximately one month; however, vegetation rebounded midseason. Tillage selected for species adapted to disturbance, such as common purslane and field bindweed. Straw mulch provided equivalent weed suppression to tillage in the early season. Straw required annual reapplication with material costs, labor, and weed-seed contamination (e.g., volunteer grains and quackgrass) as disadvantages. Plastic fabric mulch reduced weeds the most, but had high initial costs and required seasonal maintenance. Weed biomass declined within seasons and across the three years of the study, likely due to tree canopy shading. Neither birdsfoot trefoil nor a perennial grass mixture planted in the alleyways influenced treerow weeds. Our results demonstrate several viable alternatives to tillage for weed management in treerows of organic peach orchards in the Intermountain West.

Effect of different orchard management practices on the growth and production of rejuvenated of pomegranates (Punica granatum L.) cv. Kandhari Kabuli

Orchard management practices are the most important cultural tools for successful and sustainable cultivation of any fruit crop including pomegranate. Orchard management systems have an effect on growth, yield and fruit quality through their smoothening effects on the availability of nutrients, conservation of moisture and reduction of weed competition. Orchard management practices treatments viz., five orchard floor management treatments viz., T1: Grass mulch (10 cm thick), T2: Black polythene mulch, T3: Clean basin + Herbicidal treatment (Glyphosate 7ml/ litre), T4: Ridge basin + Grass mulch and T5: Control (No mulching). The results of the experiment, black several that polythene mulch proved to be most effective in increasing plant growth (51.80 cm), yield (13.05 kg/plant) of superior fruits and also in conservation of soil moisture. Grass mulch was better when compared to other orchard floor man-agement practices in terms of growth (47.00 cm) and yield (12.35 kg). The orders of the orchard floor management practices in moisture conservation are: black polythene mulch 13.51 %> grass mulch 12.38 % > ridge basin + grass mulch 9.31% > clean basin + Herbicidal treatment (Glyphosate 7 ml/litre) 9.20 %> control 7.64 %. Orchard floor management treatments did not exert any significant effect in controlling bacterial blight disease on leaf and fruit surface.

Weed management in guava orchards

The comparative efficacy of orchard soil management practices like mulching (paddy straw, white polythene, black polythene) and weed control methods (mechanical and chemical) were evaluated for managing weeds growth in guava orchard. A weedy plot was also kept as control for comparative assessment of different orchard floor management practices. The results revealed a significant effect of different treatments on grassy as well as broad-leaf weeds in the orchard. Although the black polythene mulch kept the area weed free throughout the season, the paddy straw mulch exhibited promising results, with 69.1 and 93.2% reduction in total weed biomass during first and second year of application, respectively. The white polythene was poor performer as it resulted in heavy weed growth under the mulch and tearing of polythene sheet. Chemical weed management as well as mechanical weeding also reduced the intensity of weeds but resurgence of weeds resulted significantly higher weed biomass compared to paddy straw mulch. The paddy straw mulch exhibited potential to manage weeds in guava orchard.

Does Fungicide Run-off From Citrus Delay Leaf Litter Decomposition?

Leaf litter is a major inoculum source for citrus diseases such citrus black spot caused by Phyllosticta citricarpa, and greasy spot caused by Mycosphaerella citri. In order to reduce this inoculum source, the efficacy of urea, dolomitic lime, a commercial compost accelerator, and an organic mulch, was assessed for enhanced leaf decomposition and reduction in sporocarps. However, due to the potential for run-off from high volume fungicide applications to disrupt leaf decomposition and microbial antagonism, the amendments were compared with and without simulated fungicide run-off. Mature green leaves of Citrus sinensis were removed from trees and placed inside mesh bags before being pinned to the orchard floor. The amendments were applied, and then simulated run-off from a typical citrus black spot fungicide program (copper, mancozeb, azoxystrobin) was applied. Leaf degradation was assessed every 2-3 weeks by visual ratings and dry weight. No direct effects on sporocarps could be observed due to insufficient infection. The results showed that the organic mulch was the most effective at enhancing decomposition, while there was significantly (P < 0.05) less decomposition in the presence of fungicide run-off.

Remote sensing of N deficiencies in apple and pear orchards

Innovative use of sensor technology offers the potential to provide better feedback techniques of nutrient status, resulting in the lowered expenditure on fertiliser, increased capacity to meet market specification and reduced loss of nutrients. In this study we evaluated the use of remote sensing to assess canopy N status through the Canopy Chlorophyll Concentration Index (CCCI) which has been applied to cereal crops, but was untested for apple and pear. Initial analysis suggested that 2.5 m resolution satellite imagery was not sufficient to separate the tree canopy from orchard floor vegetation. To remove the influence of the orchard understorey, test datasets of high spatial resolution imagery (<0.05 m pixel) were acquired over the canopy in a research pear orchard and commercial apple orchards. A multispectral camera was deployed in hand held mode to generate side views of the canopy, and above the canopy using an Unmanned Aerial Vehicle (UAV). CCCI determined from side viewing imagery within commercial apple orchards was compared with corresponding leaf N values taken from the same plots. The results suggest that a linear relationship between CCCI and leaf N can be established. Imagery acquired from a UAV platform validated the use of a UAV in commercial and research orchard settings to provide maps of CCCI.

Evaluating the use of harvesting systems and worker platforms in the South African deciduous fruit industry

The increasing cost of fruit production necessitates more cost-effective orchard practices on South African deciduous fruit farms. Increasing the productivity of labour is one of the components focussed on. Harvesting systems and worker platforms were tested in various production areas to evaluate the effect of these machines on worker productivity during harvesting, pruning and fruit thinning. The effect of harvesting systems on the incidence of harvest injuries was also assessed. The misalignment between typical South African deciduous fruit orchards and harvesting system design leads to a decrease in overall worker productivity during harvesting. Orchard actions where a lot of time is spent moving the ladder relative to the time spent working on the ladder showed the greatest productivity gains when performed with platforms, e.g., summer pruning and to a lesser extent dormant pruning. However, few South African orchards and operational systems are suited to the implementation of these machines and much optimization and investment will be needed to mechanize the harvesting process. Factors such as tree size, shape and uniformity, fruit distribution on the tree, fruit size and quality, orchard floor condition and aspect, labour team dynamics, harvesting incentives, bin condition, operational system employed and harvest logistics all affect the feasibility and ease of mechanization.

Effect of drip irrigation frequency, nitrogen rate and mulching on nitrous oxide emissions in a semi-arid climate: An assessment across two years in an apple orchard

Micro-irrigation scheduling and mulch application can be used by orchardists to match water supply to plant demand and conserve water. There is little information on how these management practices affect nitrous oxide (N2O) emissions from orchard soils, and most previous studies were short-term (<3 months during the growing season). We investigated (1) N2O emissions across a 2year cycle of orchard management and (2) seasonal N2O emissions by analysing measurements taken before, during and after the growing season in an apple (Malus domestica Borkh) orchard under various managements in a semiarid climate. Treatments included drip irrigation frequency (every day or every 2nd day) delivering the same total amount of water, orchard floor management (bare soil or shredded bark and wood mulch) and nitrogen application rate applied as calcium nitrate by fertigation (20 or 40gNtree−1). Over a period of two complete years, irrigation every 2nd day reduced area-scaled N2O emissions by 27% and application of shredded bark and wood mulch reduced area-scaled N2O emissions by 19%, suggesting that reduced drip irrigation frequency and mulching may provide an opportunity for suppressing N2O emissions from drip irrigated orchards. Treatment effects on N2O emissions were variable across seasons and years and a significant portion (17–51%) of the annual N2O emissions occurred during the pre-growing season particularly during freeze-thaw cycles, affirming the importance of year round monitoring when assessing the effect of managements on N2O emissions.

Effect of orchard floor management practices on soil physical properties, growth and yield of ‘Kinnow’ mandarin (Citrus reticulataBlanco)

Effect of orchard floor management practices on soil physical properties, growth and yield of ‘Kinnow’ mandarin (<i>Citrus reticulata</i>Blanco)

Differential effect of regulated deficit irrigation on growth and photosynthesis in young peach trees intercropped with grass

The effects of a moderate soil water deficit on several shoot growth variables (1st and 2nd order shoot growth and final leaves number, final height and final number of 2nd order shoots) and on net photo- synthesis were studied in young peach trees during the two years following plantation (January 2014). Trees were either fully irrigated (C), subjected to moderate water deficit (RDI) or subjected to moderate water deficit and associated with a grass-legume mixture on the entire orchard floor (RDI +G). Irrigation was scheduled according to soil water potential target ranges in order to keep C trees above −0.02 MPa, i.e. at field capacity, and RDI and RDI + G trees between −0.04 MPa and −0.06 MPa. The level of water deficit obtained was moderate but yet significantly reduced by 50% overall tree growth in 2014 in RDI. This reduction was enhanced when water deficit lasted longer and when it was associated with grass in RDI + G. No reduction in growth variables occurred in RDI in 2015 due to the shorter duration of water deficit. Overall reduction was observed in 2015 in RDI + G mostly due to a carry-over effect of the pre- vious year. Net photosynthesis was reduced by the longer and more intense water deficit in 2014, but was not reduced during the soil water deficit in 2015. An indicator of plant process sensitivity to water deficit, taking into account the variable reduction with regards to the control, the water deficit intensity and its duration was used to classify shoot growth variables and net photosynthesis according to their sensitivity to water deficit. Variables could be classified according to the following order of ascending sensitivity: net photosynthesis <1st order final leaf number < final tree height <1st order final shoot length <2nd order final leaf number <2nd order final shoot number <2nd order final shoot length. Applying a moderate water deficit combined with full grass cover drastically reduces overall tree size due to grass competition

Crop loss and control of Pseudocercospora fruit and leaf spot of citrus in Ghana

Pseudocercospora fruit and leaf spot (PFLS) of citrus, caused by Pseudocercospora angolensis, was recently described in Ghana and has spread in most citrus-growing areas of the country. A survey of PFLS incidence was conducted in the Eastern Region. Orchards were georeferenced and data on altitude, annual mean temperature, and annual precipitation were obtained from the WorldClim database. Fruit drop due to PFLS and other pests and diseases was evaluated in three orchards. Field efficacies of 4-week, 6-week and 8-week schedules with carbendazim + mancozeb were evaluated in the major and minor fruit production seasons. Ordinal logistic regression and generalized linear models were fitted in each case according to the nature of the data and possible overdispersion. Disease incidence in the sweet orange orchards surveyed was 25–100 %, with higher values in higher altitude areas exposed to lower temperatures and higher rainfall. PFLS was the main problem causing yield losses, associated with 84–87 % of fruit dropped on the orchard floor. PFLS severity on shoots and incidence on fruit 12 weeks after full bloom was significantly reduced by all fungicide schedules evaluated. The effects of fungicides on PFLS severity in fruit at harvest were not substantial because of intense fruit drop. The 8-week schedule showed the lowest effectiveness in reducing fruit drop and thus the 6-week schedule is preferred. Further research is needed for an integrated management of PFLS in Ghana.

Quantifying the potential contribution of soil carbon to orchard carbon footprints

Increasing soil carbon is promoted to growers as a means of increasing soil function and mitigating climate change. However, the importance of soil carbon is not yet fully acknowledged in life cycle assessment guidelines. Because of their perennial nature and deep rooting systems, orchards have the potential to increase subsoil carbon stocks below 0.3 m depth. Quantifying soil carbon stocks at the orchard scale, however, requires sampling protocols that incorporate the spatial variability of carbon in orchards. We have investigated soil carbon stocks to 1 m depth in apple orchards in Australia and New Zealand and found that total carbon stocks were maintained over four to 12 years. Orchard floor management practices can create a spatial distribution of shallow soil carbon stocks, and we observed a trend for decreasing surface-soil carbon stocks under the alley. Additionally, we determined soil carbon stocks to 9 m depth in a New Zealand kiwifruit orchard and calculated an increase of 190 t C ha-1 after 30 years compared with that in the nearby pasture soil that was the antecedent land-use. This increase in soil carbon equates to 42% of the carbon footprint of New Zealand kiwifruit on United Kingdom supermarket shelves. Therefore, accurately quantifying soil carbon stock changes under orchard systems presents a potential opportunity to reduce horticultural carbon footprints.

Soil quality index as affected by different cropping systems in northwestern Himalayas.

Soil quality assessment provides a tool for evaluating the sustainability of soils under different crop cafeterias. Our objective was to develop the soil quality index for evaluating the soil quality indicators under different cropping systems in northwest Himalaya-India. Composite soil samples were taken from the study area from different cropping systems which include T1 (forest soil control), T2 (rice-oilseed, lower belts), T3 (rice-oilseed, higher belts), T4 (rice-oats), T5 (rice-fallow), T6 (maize-oats), T7 (maize-peas), T8 (apple), T9 (apple-beans), and T10 (apple-maize). Physical, chemical, and biological soil indicators were determined, and it was found that soil enzyme activities involved in nutrient cycling were significantly higher in forest soils, which were reflected in higher levels of available pool of nutrients. Carbon stocks were found significantly higher in forest soil which was translated in improved soil physical condition. Principal component analysis (PCA) was performed to reduce multidimensionality of data followed by scoring by homothetic transformation of the selected indicators. Pearson's interclass correlation was performed to avoid redundancy, and highly correlated variables were not retained. Inclusion of legumes in the apple orchard floor recorded highest soil quality rating across the treatments. Cereal-based cropping systems were found in lower soil quality rating; however, the incorporation of peas in the system improved soil health.

A model of macadamia with application to pruning in orchards

A self-organising model of macadamia, expressed using L-Systems, was used to explore aspects of canopy management. A small set of parameters control the basic architecture of the model, with a high degree of self-organisation occurring to determine the fate and growth of buds. Light was sensed at the leaf level and used to represent vigour and accumulated basipetally. Buds also sensed light so as to provide demand in the subsequent redistribution of the vigour. Empirical relationships were derived from a set of 24 completely digitised trees after conversion to multiscale tree graphs (MTG) and analysis with the OpenAlea software library. The ability to write MTG files was embedded within the model so that various tree statistics could be exported for each run of the model. To explore the parameter space a series of runs was completed using a high-throughput computing platform. When combined with MTG generation and analysis with OpenAlea it provided a convenient way in which thousands of simulations could be explored. We allowed the model trees to develop using self-organisation and simulated cultural practices such as hedging, topping, removal of the leader and limb removal within a small representation of an orchard. The model provides insight into the impact of these practices on potential for growth and the light distribution within the canopy and to the orchard floor by coupling the model with a path-tracing program to simulate the light environment. The lessons learnt from this will be applied to other evergreen, tropical fruit and nut trees.

The Effect of Seed Treatments on the Germination of Different Fabaceae Species of a Natural Meadow-Like Association

The goal of our experiment is to compose a species-rich seed mixture suitable for soil covering in orchard floor management in organic fruit production systems. Besides selection of traditionally used grass and Fabaceae species we are focusing on the involvement of local fora elements, of the experiment site, approaching a natural meadow-like association. Species of the following plant families are involved: Apiaceae, Asteraceae, Rosaceae, Linaceae, Polygonaceae, Dipsacaceae, Fabaceae, Poaceae. Seeds of selected species were tested to determine germination % before seeding, according to MSZ 6354-3:2008 standard in climate cabinet. Seed treatments (vernalisation, scarification) were carried out according to relevant standard. There were differences in the germination% of commercial and wild collected seed items of Agrimonia eupatoria L, Ajuga genevensis L, Lotus corniculatus L, and Achillea millefolium L. The applied seed treatments resulted significant difference between the treated and non-treated seed items most of the tested species related their germination%. For example in case of Anthyllis vulneraria L it was effective. Scarification was effective for commercial hard seed species like Lotus corniculatus L in our case, but it was not effective for Agrimonia eupatoria L. The aim of the treatments was to select those species which can be seed in the same time, will be easier applied to soil and climatic condition of the experiment site and to determine effect of pre-treatments on germination % of seeds of tested species.

Cost and return analysis of different treatments of mulching and herbicide application on Peach (Prunus persica (L.) Batsch) cv. Shan-e-Punjab

The trees of peach cv. Shan-e-Punjab were treated with different orchard floor management practices (mulching and herbicidal treatment) in the month of February 2014. In all, there were 14 treatments including mulches viz., black polythene, paddy straw, saw dust, white polythene and herbicides viz., atrazine 50 WP (1.0, 1.5 and 2.0 Kg a.i. per hectare), oxyflurofen 23.5 EC (0.5, 0.75 and 1.0 l a.i. per ha) and pendimethalin 30 EC (1.0, 1.5 and 2.0 l a.i. per ha) and control which were replicated thrice. The total cost of cultivation per hectare was found to be highest ( 207480.00) in treatments T1 and T2 i.e. black polythene mulch and white polythene mulch, respectively whereas, it was found to be lowest of 185240.00 in the treatment (T14) i.e. control. Among all the treatments, the benefit: cost ratio was found highest with black polythene mulch (1:1.89) followed by atrazine 2.0 kg a.i/ha (1:1.86) and lowest in control (1:1.55). Thus, for improving growth, yield and fruit quality of peach cv Shan-e-Punjab, black polythene mulch and atrazine 2.0 kg a.i/ha are found to be most suitable and economically feasible under the Jammu sub- tropics.

TRANSPIRATION OF PEAR TREES AND IMPLICATIONS FOR IRRIGATION SCHEDULING

Lack of water for irrigation due to changing climate is emerging as the biggest threat to the viability and sustainability of the pear industry in Australia. Using less irrigation, maintaining productivity and clearly demonstrating eco-efficient irrigation can be achieved by a better understanding of crop water requirements in different environments, tree training and trellising systems, and management scenarios. Crop water requirements in high-density pear orchards were investigated by relating transpiration (T) measured using the sap flow method, to reference crop evapotranspiration (ETo) and effective area of shade (EAS) in two commercial ‘Williams’ Bon Chretien’ pear orchards. EAS was estimated from photosynthetically active radiation (PAR) sensors installed in a grid pattern between trees and rows on the orchard floor. Seasonal changes in T increased after full bloom to reach a maximum in mid-summer and then steadily declined in late summer and autumn. EAS remained relatively constant at 0.6 in both orchards for most of the season apart from the first 30 days after full bloom and at leaf fall. There was a similar positive linear relationship between daily T and EAS-weighted ETo in both orchards for pre- and postharvest data excluding the period of withholding irrigation when trees were likely to be water stressed. The results suggest that full irrigation of pear trees can be estimated from 1.1 EAS ETo up to harvest. Postharvest full irrigation requirements appear to be less and can be estimated from 0.8 EAS ETo. Our measurements showed that EAS remained relatively constant over the irrigation season making the task of scheduling much easier, with simple recommendations based on a single measure of EAS and an ETo deficit.

Variation in urease and β-glucosidase activities with soil depth and root density in a ‘Cripp's Pink’/M7 apple orchard under conventional and organic management

The effects of conventional (CON; utilising synthetic fertiliser and herbicide) and organic (ORG; nutrients supplied in compost, weeds controlled with straw mulch) orchard floor management practices on depth-wise variation in urease and β-glucosidase activities in tree-row soils were compared in a Western Cape ‘Cripp's Pink’/M7 apple orchard. Urease and β-glucosidase activities were determined spectrophotometrically in soils from five depth intervals from the walls of trenches excavated across the tree rows after seven years of treatment application. Soil pH, organic carbon, nitrate (NO3 ) and ammonium (NH4 ) nitrogen were also determined, as was root density. Enzyme activities were higher in the ORG than the CON topsoils but did not differ significantly (p = 0.05) at depths >30 cm. The positive effects of the ORG treatments were attributed to the liming effect and carbon and nitrogen contributions of the compost. Urease and β-glucosidase activities correlated strongly. Activities of both enzymes correlated significantly and positively with carbon, NO3− and pH, with urease correlated more strongly than β-glucosidase. Only urease correlated with root density. Organic orchard floor management practices may be more effective than CON practices in promoting microbial enzyme activities in the 0–30 cm soil depth intervals of Western Cape apple orchard soils.

Effect of conventional and organic orchard floor management practices on arbuscular mycorrhizal fungi in a ‘Cripp’s Pink’/M7 apple orchard soil

Arbuscular mycorrhizal (AM) fungi are key components of agricultural soil–plant systems, which may be affected by agricultural practices. In organically managed (ORG) orchards, nutrients are supplied in the form of compost, and weeds are suppressed with mulches, whereas synthetic fertilizers and herbicides are used for these respective purposes in conventional (CON) orchards. The effects of ORG and CON orchard floor management practices on native AM fungi in apple orchards were investigated in a randomized field trial. AM root colonization, spore abundance, infectivity potentials and soil glomalin contents were determined in the 0–30cm soil depth interval, in tree rows, over consecutive seasons. Root colonization was higher in the ORG than the CON treatments, but intermediate where straw mulch was substituted for green work-row covers. Glomalin levels were not affected by the treatments. Root colonization by AM fungi increased with increasing soil pH, P, C, K, Zn, and Mn concentrations, but were suppressed by Cu. Colonization correlated positively with leaf P, Ca and Mg, and with stem circumference, but negatively with leaf N and yield. ORG orchard floor management practices therefore, promoted functional AM associations more effectively than CON practices.

Vegetation-free Width and Irrigation Impact Peach Tree Growth, Fruit Yield, Fruit Size, and Incidence of Hemipteran Insect Damage

Orchard floor vegetation competes with peach trees for water and nutrients and may harbor pathogens and insects. Tree growth, fruit yield, and fruit size can be optimized through management of vegetation in the tree row and irrigation. Under-tree vegetation-free strip widths (0, 0.6, 1.2, 2.4, 3.0, and 3.6 m) and irrigation were studied in years four through eight of a young peach orchard to determine their effects on peach tree growth and fruit yield, harvest maturity, and fruit size. Immature fruit samples were collected during thinning in years four through six to determine the effect of the treatments on the incidence of hemipteran (catfacing) insect damage. Trunk cross-sectional area (TCSA), as a measure of tree growth, increased with increasing vegetation-free strip width; trees grown in the 3.6-m vegetation-free strip had TCSAs 2.2 times greater, on average, than trees grown in the 0-m vegetation-free strip. TCSA also increased with irrigation; trees grown with irrigation had TCSAs 1.2 times greater, on average, than trees grown without irrigation. Yield increased with increasing vegetation-free strip width, from 9.6 kg per tree in the 0-m plot to 26.5 kg per tree in the 3.6-m plot in year four, to 24.3 kg per tree in the 0-m plot and 39.6 kg per tree in the 3.6-m plot in year eight, for a total yield over years 4–8 per tree of 100 kg in the 0-m plot compared with 210 kg per tree in the 3.6-m plot. Yield, average fruit weight, and average fruit diameter increased with irrigation in three of 5 years; the other 2 years had higher than average rainfall reducing the need for supplemental irrigation. In 3 out of 5 years fruit in irrigated plots matured earlier than fruit in nonirrigated plots. In all years, fruit grown in the 0-m strip matured earliest and had the smallest diameter. Establishing a vegetation-free strip of as narrow as 0.6 m reduced the incidence of catfacing damage compared with the 0-m treatment, even though the orchard was on a commercial pesticide spray schedule. The least damage was seen with the industry standard vegetation-free strip widths greater than 3.0 m with or without irrigation.

Effect of conventional and organic orchard floor management practices on enzyme activities and microbial counts in a ‘Cripp's Pink’/M7 apple orchard

Organic (ORG) production practices are increasingly being used in South African apple orchards. Whether ORG orchard floor management practices differ in their effects on soil enzyme activities and microbial populations from conventional (CON) practices have not been adequately investigated, particularly with regard to soil chemical characteristics and orchard performance. To seek clarification a randomised field trial was carried out in the winter rainfall region of the Western Cape. In this trial ‘Cripps Pink’/M7 apple trees received straw mulch with compost (ORG) or synthetic fertiliser and herbicide (CON) in the tree rows. Soil microbial enzyme activities and microbial counts were determined by colorimetric assays and dilution plating, respectively. Activities of β-glucosidase, acid phosphatase and urease, and actinobacteria counts tended to be greater in the ORG than the CON treatments. Activities correlated positively with soil zinc and manganese concentrations and with leaf zinc, but negatively with soil copper. β-glucosidase and acid phosphatase activities also correlated negatively with ammonium and nitrate nitrogen in the soil, and with leaf nitrogen concentration. Yields decreased with increasing β-glucosidase and acid phosphatase activities. Therefore, although ORG practices increased soil microbiological activity relative to CON management, they did not improve yield.