Cultural Treatments Research Articles

Creeping bentgrass summer decline as influenced by climatic conditions and cultural practices

AbstractDespite its popularity as a putting surface in North Carolina, creeping bentgrass (Agrostsis stolonifera L.) is highly susceptible to summer bentgrass decline (SBD) during hot summer months. Cultural practices have been shown to help alleviate the pressure of SBD. The objectives of this study were to detail the impacts of N fertility, soil water content, and hollow‐ and solid‐tine cultivation on creeping bentgrass quality. Cultural treatments included four N rates (97, 195, 293, and 391 kg ha−1 yr−1), four hollow‐tine core cultivation programs (6.4 mm diam. tines two times yr−1, 9.5 mm diam. tines two and three times yr−1, and a non‐cored control), two soil water content levels (low and high), and two summer solid‐tine spiking cultivation treatments (spiked and not spiked). Visual turfgrass quality was measured. A N rate greater than 195 kg ha−1 was needed to maintain acceptable turfgrass quality. High soil water content consistently provided better summer turfgrass quality compared to low soil water content conditions. Nitrogen fertility and soil water content interacted where higher levels of both resulted in the best quality ratings. Hollow‐core cultivation reduced turfgrass quality at the lower N rates; whereas, solid‐tine spiking had no effect on turfgrass quality. Although weather plays a large role in SBD in North Carolina, results from this study show that cultural practices can influence its severity.

BIOLOGI Ooencyrtus malayensis Ferr. PARASITOID TELUR Dasynus piperis China, PADA INANG ALTERNATIF Nezara viridula L.

<p><strong>Biology of egg parasitoid ('Ooencyrtus malayensis Ferr.) ofpepper bug on alternate egg host (Nezara viridula L)</strong></p><p>Pepper bug (Dasynus piperis China) is an important pest of pepper. The pest widely spread in most pepper plantations of Indonesia. The level of the pest attack varied depended on crop cultivation treatment. Ooencyrtus malayensis is one of natural enemies which is able to control the population of pepper bug in plantation. The objective of this research was to study some aspects of the egg parasitoid biology by using eggs of Nezara viridula as the alternate host. This research was designed in a completely randomized block with four replicates. Dasynus piperis was collected from Bangka island and reared in Laboratory of the Research Institute for Spice and Medicinal Crops (RISMC ). Nezara viridula was fed with cowpea bean. This reascarch was conducted from July 1998 to February 1999. Experiment was divided into seven steps such as oviposition. pre adult period, production of parasitoid per host egg. egg preference, infestation period effect of cold storage (4°C) and parasitoid population. Research results showed that there were 85.5 parasitoid produced during its life time. Pre adult period lasted from 12 to 16 days, alternate host produced 3 parasitoids. The parasitoid pefeed the host of 0-2 days old. The eggs could be stored for 25 days in a efrigenerator (4°C). The longer the infestation and the larger number of parsitoid infested the larger numbers of parasitoid produced.</p>

Reflective material in the formation of Dipteryx alata seedlings

The study aimed to evaluate the influence of reflective materials on the cultivation bench and the use of rice husks over the substrate in the formation of Dipteryxalata seedlings. The experiment was carried out in the experimental area of the Mato Grosso do Sul State University, in Cassilândia-MS, from November 1st, 2016 to January 26th, 2017. A completely randomized design in a 5 x 2 factorial scheme was used, with five replications and five plants per plot. Four reflective material for the cultivation bench and treatment without reflective material (control), combined with or without rice husks over the substrate (0.5 cm layer), were evaluated. Laminated paper tray, mirror, reflective fabric (known as “fake sequin fabric”), and aluminum foil were used as reflective materials. The reflecting materials did not differ in the reflectance of photosynthetically active radiation. However, the mirror and the aluminum foil reflected more than the control. The use of rice husk over the substrate did not increase the Dipteryxalata seedlings' quality. The mirror as a reflective material produced Dipteryxalata seedlings of higher quality than the system without material reflector called control.

Post treatment of swine anaerobic effluent by weak electric field following intermittent vacuum assisted adjustment of N:P ratio for oil-rich filamentous microalgae production

A weak electric field (EF) was applied to decolorize the swine anaerobic effluent, which was followed by N:P ratio adjustment via intermittent-vacuum stripping (IVS) system for oil-rich filamentous microalgae Tribonema sp. cultivation. A higher electric field strength, higher temperature, and lower pH conditions showed higher efficiency in decolorization and nutrients removal during EF application. In the group of 30:1 (N:P) ratio, Tribonema sp. had the largest biomass accumulation (2.04 g·L−1) after 14 days cultivation. However, the 20:1 group had highest oil accumulation (oil content 55.4 ± 3.4%), while 30:1 (N: P) group was 42.3 ± 1.8%. Under the conditions of sufficient nitrogen (50:1 group), the highest contents of α-linolenic acid (15.5%) and ω-3 fatty acids (21.8%) were reached. The integrated treatment of EF, IVS and microalgae cultivation demonstrated to be effective for nutrients recycling and sustainable biomass production.

Estimation of Canopy Area of Fruit Trees Using Light Unmanned Aerial Vehicle (UAV) and Image Processing Methods

Some vegetative properties measured in fruit trees are important indicators in examining of plant growth calculation, estimation of leaf area index in evapotranspiration, fertilizer requirement etc. These measurements reflect the effects of the cultivation treatments in many areas of commercial growing and scientific studies. One of the most important measurements is the status of the canopy development. Canopy width, area and volume can be measured with some calculations. However, more technological equipment may be needed to reduce work and labor, and to make the results more precise and clearer. Recently, unmanned aerial vehicles, which have become widespread, have a wide potential for use in agriculture. By using image processing methods, it is possible to make more objective and high accuracy evaluations much faster. In this study, the images of the apple trees (Malus domestica Borkh) cultivar Golden grafted onto MM106 rootstock, were taken by light unmanned aerial vehicle to calculate the canopy area and then these images were analyzed using image processing methods for calculating canopy areas. Both circular and elliptical calculation methods were used. The area calculations with image processing methods were compared with the areas obtained manually. Comparisons were made by regression analysis. For the most successful method R value was 0.9662 for elliptic area and 0.9346 for circular area which was calculated by image processing. The results demonstrated that the image processing can be an alternative method to determine the canopy area according to accuracy ratios.

Evaluation of the Crop Yield and Nutrient Balance by Application of Liquid Manure in Paddy Soil

The purpose of this study was to evaluate the effects of liquid manure to increase the yield of green manure in winter season, and to investigate the effect of green manure incorporation to increase the yield of maize grain and nutrient balance improvement in upland soil. The green manure used in this experiment was barley and hairy vetch with a mixed ratio of barley and hairy vetch (75:25), respectively. Liquid manure applied 0, 26, 52, 78, and 104 Mg ha-1, respectively, and the half of the total amount was applied as basal fertilizer, and the other half was topdressing. Nitrogen inputs through liquid manure were 0, 7.1, 15.6, 21.5 and 28.4 kg ha-1, respectively, and the phosphorus inputs were 0, 11.3, 22.6, 33.9 and 45.2 kg ha-1, respectively. The yield of green manure crops increased significantly with the increase of liquid manure application, but the yield of hairy vetch decreased. In the summer season, the green manure crops were incorporated, and the compost was used in the conventional treatment. The yield of maize grain increased with increasing green manure yield. The yield of maize grain of green manure crops incorporation treatments was up to 81% compared to conventional cultivation treatment, however the two-year experiments showed an increase on maize grain yields in green manure incorporation treatment. In addition, the incorporation of green manure crops greatly improved the phosphorus balance in compared to conventional cultivation. Therefore, productivity improvement of green manure crops by utilizing liquid manure is thought to have significantly contributed to the improvement of maize grain yield and nutrient balance. The effect of green manure incorporation on the maize grain yield with different rate of liquid manure application for two years. The maize grain yield of PM4 treatment was 759 kg 10a-1, and up to 81% in compared with the NPK treatment in 2017. However, the maize yield of incorporation green manure treatment in 2017 tended to increase in compared with that of in 2016.

Midseason cultivation effects on anthracnose of annual bluegrass turf

AbstractMechanical injury from cultivation practices is reported to enhance anthracnose disease, caused by the fungus Colletotrichum cereale Manns sensu lato Crouch, Clarke, and Hillman, of annual bluegrass (ABG) [Poa annua L. forma reptans (Hausskn.) T. Koyama]. Two field experiments were initiated with the objectives of determining the effects of midseason cultivation practices (Experiment 1) and scarifying depth (Experiment 2) on anthracnose severity of ABG maintained at a 3.2‐mm mowing height on a Nixon sandy loam in North Brunswick, NJ. Experiment 1 treatments consisted of grooming, verticutting, scarifying, and solid‐tining every 21 d as well as weekly grooming and no cultivation over 2 years. Experiment 2 evaluated single treatments of shallow and deep scarifying and a nontreated control in three runs. Verticutting increased the area under the disease progress curve (AUDPC) compared with no cultivation during the first year, whereas verticutting and scarifying increased AUDPC relative to no cultivation during the second year. No other cultivation treatments differed from the control during either year in Experiment 1. In Experiment 2, scarifying did not increase AUDPC during any run at either depth. Results from these experiments indicate that cultivation practices that affect at least 15% of the turf surface area and injure crowns may increase anthracnose severity, whereas practices that affect a smaller turf area or only leaf tissue will not increase disease severity.

Long-term impacts of soil compaction and cultivation on soil carbon and nitrogen pools, foliar δ13C and δ15N as well as tree growth in a hoop pine plantation of subtropical Australia

The aim of this study was to examine the long-term impacts of mechanical compaction and cultivation on soil C and N pools, δ13C and δ15N of soil and foliage as well as tree growth. In a hoop pine plantation of subtropical Australia, the diameter at breast height over bark (DBHoB) and tree height; δ13C and δ15N of soil and foliage; and soil C and N pools were determined after 17 years following forwarder compaction (control, light and heavy) and cultivation (control and disc plough) treatments. Light compaction was associated with the significantly higher soil total carbon (TC) and total nitrogen (TN) in the 20–30 cm soil and higher TN in the 30–60 cm soil (p < 0.01). Cultivation was linked to the significantly higher soil TC in the 0–10 cm soil, and TC, TN and hot water-extractable total nitrogen (HWETN) in the 10–20 cm soil (p < 0.01). Higher δ15N in the 0–10 cm soil and in the foliage in the heavily compacted plots was due to previous soil denitrification, while light compaction and cultivation were associated with the lower foliar δ13C due to decreased foliar N concentration and reduced photosynthesis rate with increasing foliar biomass under higher N supply. The δ13C and δ15N of foliage and soil were useful indicators of the C and N processes in plant-soil system in response of management impacts in the plantation. Light compaction and cultivation generally had beneficial impacts on soil C and N pools over long term, whereas there was no difference in the impacts of different compaction and cultivation treatments on tree growth.

Evapotranspiration and crop coefficients of Italian zucchini cultivated with recycled paper as mulch.

Recycled paper has the potential to be used as a mulch for vegetable production and can be adopted for the cultivation of Italian zucchini. However, there have been no studies about the water savings or crop coefficient values used in irrigation management in this system; therefore, there is a need for more research. In view of the above, this study aimed to evaluate the effects of recycled paper mulch on evaporation and evapotranspiration in Italian zucchini and to determine the crop coefficients in its developmental stages. The study was carried out in two cultivation cycles conducted at the Lysimetric Station in Viçosa, MG, Brazil. The experiments were installed in a randomized block design with four replicates. Four lysimeter cultivation treatments were applied: without mulch (C); with recycled paper as mulch (CP); with only recycled paper (P); and with Bahia grass (G). Irrigation and drainage measurements were performed daily to calculate the crop and reference evapotranspiration, and thus the crop coefficient (Kc) values. The following characteristics were evaluated: fruit yield, NDVI and water productivity. For the cultivation of Italian zucchini using paper as mulch, Kc values of 0.54, 0.77 and 0.44 and Kcb values of 0.15, 0.45 and 0.18 are recommended for the initial, intermediate and final stages, respectively. NDVI can be used to estimate the Kc values for Italian zucchini. The use of recycled paper as mulch reduces the water consumption of Italian zucchini.

The Ursolic Acid Content of Rumput Mutiara (Hedyotis corimbosa L.) Grown in Various Locations

Hedyotis corimbosa L. or Rumput Mutiara (Indonesian Local name) is one of the plants that is getting more famous as an herbal medicine and is consumed by the public to cure diseases or to maintain health. All parts of Hedyotis corimbosa L. can be used as an efficacious drug, which is an anti-inflammatory, anticancer, antipyretic, diuresis, blood circulation, antitoxin, etc. As an herbal ingredient, Hedyotis corimbosa L. is currently known as a wild plant that has not been popularly cultivated, thus the quality of Hedyotis corimbosa L. is varied. Therefore, it is necessary to map which areas produce Hedyotis corimbosa L. with highest ursolic acid. This study aimed to determine the content of ursolic acid in Hedyotis corimbosa L. from its various different growth locations. This research applied thin layer chromatography techniques and the analysis of variance with a level of α = 5% using Unbalanced Incomplete Block Design. The results showed that site altitude treatment did not show any significant difference in the number of leaves, root length, plant height, node length, stem diameter, number of branches, leaf width, leaf length, flower stem length, total extract Yield, and ursolic acid levels. Still, it showed significantly different effects on water content, dry rendement, and productivity. The correlation analysis showed that there is no significant correlation at α = 5% between ursolic acid content and root length, plant height, leaf width, leaf length, and total extract Yield while node length, stem diameter, number of branches, flower stem length, number of leaves, dry rendement and productivity showed a significantly positive correlation with ursolic acid content. Water content showed significantly negative correlation with ursolic acid content. The conclusion is that there is no significant difference in ursolic acid content from plants grown at low altitudes and medium altitude. However, the content of ursolic acid from medium altitude is relatively higher compared to ursolic acid content from low altitude. This implies that there is a tendency for ursolic acid content in Hedyotis corimbosa L. to be influenced by the conditions of its growth location so that cultivation treatment with different conditions will affect the ursolic acid content.

Increased soil moisture aggravated the competitive effects of the invasive tree Rhus typhina on the native tree Cotinus coggygria

BackgroundInvasive exotic species have caused significant problems, and the effects of extreme precipitation and drought, which might occur more frequently under the global climate change scenarios, on interspecific relationship between invasive and native species remain unclear.ResultsWe conducted a greenhouse experiment with three soil water levels (30–40%, 50–60%, and 70–80% of field capacity) and two cultivation treatments (monoculture pots, one seedling of either species and mixture pots, one seedling of each species) to investigate soil water content effects on the relationship between invasive Rhus typhina and native Cotinus coggygria. Rhus typhina had lower height but bigger crown area than C. coggygria in the monoculture treatment. Rhus typhina had higher height, bigger crown area and total biomass than C. coggygria in the mixture treatment. Drought decreased the growth parameters, total chlorophyll concentration, and leaf biomass, but did not change gas exchange and other biomass parameters in R. typhina. The growth parameters, leaf area index, biomass parameters, total chlorophyll concentration, and net photosynthetic rate of C. coggygria decreased under drought conditions. The log response ratio (lnRR), calculated as ln (total biomass of a target plant grown in monoculture/total biomass of a target plant grown in mixed culture), of R. typhina was lower than that of C. coggygria. The lnRR of R. typhina and C. coggygria decreased and increased with increase in soil water content, respectively.ConclusionsRhus typhina has greater capacity to relatively stable growth to the drought condition than C. coggygria and has strong competition advantages in the mixture with C. coggygria, especially in the drought condition. Our study will help understand the causes of invasiveness and wide distribution of R. typhina under various moisture conditions and predict its expansion under climate change scenarios.

Embryo-derived teratoma invitro biological system reveals antitumor and embryotoxic activity of valproate.

Antiepileptic/teratogen valproate (VPA) is a histone deacetylase inhibitor/epigenetic drug proposed for the antitumor therapy where it is generally crucial to target poorly or undifferentiated cells to prevent a recurrence. Transplanted rodent gastrulating embryos‐proper (primitive streak and three germ layers) are the source of teratoma/teratocarcinoma tumors. Human primitive‐streak remnants develop sacrococcygeal teratomas that may recur even when benign (well differentiated). To screen for unknown VPA impact on teratoma‐type tumors, we used original 2‐week embryo‐derived teratoma in vitro biological system completed by a spent media metabolome analysis. Gastrulating 9.5‐day‐old rat embryos‐proper were cultivated in Eagle's minimal essential medium (MEM) with 50% rat serum (controls) or with the addition of 2 mm VPA. Spent media metabolomes were analyzed by FTIR. Compared to controls, VPA acetylated histones; significantly diminished overall teratoma growth, impaired survival, increased the apoptotic index, and decreased proliferation index and incidence of differentiated tissues (e.g., neural tissue). Control teratomas continued to grow and differentiate for 14 days in isotransplants in vivo, but in vitro VPA‐treated teratomas resorbed. Principal component analysis of FTIR results showed that spent media metabolomes formed well‐separated clusters reflecting the treatment and day of cultivation. In metabolomes of VPA‐treated teratomas, we found elevation of previously described histone acetylation biomarkers [amide I α‐helix and A(CH3)/A(CH2)]) with apoptotic biomarkers within the amide I region for β‐sheets, and unordered and CH 2 vibrations of lipids. VPA may be proposed for therapy of the undifferentiated component of teratoma tumors and this biological system completed by metabolome analysis, for a faster dual screening of antitumor/embryotoxic agents.

The Effect of Soil Tillage Equipment on the Recharge Capacity of Infiltration Ponds

The Dan Region Reclamation Project (Shafdan) reclaims ~125 millions of cubic meters per year (Mm3/year) of treated wastewater from the Tel Aviv Metropolitan area. Following secondary treatment, the effluent is recharged into a sandy aquifer for soil aquifer treatment (SAT). Over the past three years, a decrease in recharge capacity was noticed. Several operational causes were considered including reservations regarding the tillage procedure of recharge ponds. Tillage of the recharge ponds facilitates aeration, breaking surface crusts and the removal of vegetation. The procedure includes deep (40–60 cm) plowing and shallow (10–20 cm) sweep-knives (SK) cultivator or discus. In this research, the existing tillage equipment was compared to a new equipment, which includes a deep subsoiler and a chisel-knives (CK) cultivator. The effects of each tool on the infiltration rate (IR), recharge capacity, and soil compaction were examined. The results suggest a significant improvement in the recharge capacity, up to 95% and 15% on average following subsoiler and CK cultivator treatments, respectively, with respect to the existing plowing treatment. In addition, the depth of the compacted soil layer increased from ~30 to ~55 cm after subsoiler treatment. It seems that this shallow layer, developed under an improper tillage regime, played a major role in the reduction of the recharge capacity. Essential understanding of other operational factors such as drying periods, preparation of the field, and soil micro-topography was also achieved.

Long-term impacts of topsoil depth and amendments on soil physical and hydrological properties of an Alfisol in central Ohio, USA

Soil hydrological properties and aggregate stability are strongly impacted by erosion and management practices. However, magnitudes of the erosion-induced changes in topsoil depth and the attendant alterations in soil properties are not well understood. Therefore, the present study was conducted on a long term (20 years) simulated study of topsoil depth and use of soil amendments to monitor changes in soil hydrological properties, and aggregate stability of an Alfisol at the Waterman Farm of The Ohio State University, Columbus, Ohio. The aim of the study was to compare long-term effects of soil amendments (synthetic fertilizer and organic compost) on soil physical and hydrological properties at varying soil depth. The experimental plots, comprising of five treatments, were laid out in Randomized Block Design and replicated thrice. Treatments were: (1) topsoil removed (20 cm deep), (2) undisturbed topsoil (intact topsoil); with two soil amendments: (a) synthetic fertilizer 150 kg nitrogen (N) ha−1 yr−1, (b) organic compost at 20 Mg ha−1 yr−1, and (3) a permanent grass field (as a benchmark plot). Soil properties, measured for 0–10 cm and 10–20 cm depth, were: texture, aggregate stability, geometric mean diameter (GMD) of aggregates, water retention properties, hydraulic conductivity (Ks), pore size distribution, and plant available water capacity (PAWC). Aggregate stability was the highest (87.9 and 84.7%) in the permanent grass at 0–10 cm and 10–20 cm depths, respectively. Among the cultivated treatments, compost- amended undisturbed plots (87.6 and86.9%) had the highest proportion of water stable aggregates (WSA) at 0–10 cm and 10–20 cm depths, respectively. However, the GMD of aggregates was the highest 4.1 mm (0–10 cm) and 3.5 mm (10–20 cm) for the topsoil removed and compost-amended treatment. Soil texture was silty clay loam in topsoil removed treatments, clay loam in the undisturbed treatment, and loam in permanent grass treatment, probably due to artificial removal of topsoil. Plant available water content was more in the disturbed and undisturbed compost-amended plots for both the 0–10 and 10–20 cm depths, respectively. The highest soil water volumetric content ranged from 0.37 to 0.25 m3 m−3 in the topsoil removed fertilizer added compared with 0.34 to 0.24 m3 m−3 in undisturbed compost added plots, respectively. However, the pore size distribution was not affected by treatments at the 0–10 cm depth. For the10-20 cm depth, an overall greater pore size distribution range of 0.04 to 0.33 m3 m−3 was observed in the permanent grass, and undisturbed compost amended treatments. Soil Ks (cm day−1) for 0–10 cm depth did not differ significantly across treatments. The data obtained enhances the understanding of the impacts of long-term use of amendments on soil water retention and aggregate stability of simulated topsoil removed and undisturbed field under no-till (NT) in corn (Zea mays)–soybean (Glycine max L. Merr.) rotation in the Eastern Corn Belt of the U.S.

Fermentasi Produksi Asam Sitrat menggunakan Aspergillus Niger ATCC 16404 dengan Substrat Hidrolisat Cair Limbah Padat Industri Brem

Dregs of solid waste brem industry contained 12 percent of sugar and 10,8 percent of starch. Component contained in the dregs are expected to produce citric acid. The aims of this study were to determine the effect of static cultivation on the production of citric acid from liquid hydrolyzate brem waste by using Aspergillus niger. The experimental design used in this study was a simple randomized block design (RAK), which the static cultivations (0, 1, 2, 3 days) as a treatment. The results showed that the static cultivation treatment significantly affected the level of acidity (pH), total soluble solids, biomass, reducing sugar, calcium citrate, citric acid and yield. The static cultivation for 1 day was the best treatment to produce Ca-citrate which the production level was 3,84 ± 0,05 g/L. By the stoichiometry method the citric acid production could be calculated, which equal to 2,12 ± 0,03 g/L.&#x0D; Keywords: Aspergillus niger, dregs of brem, static cultivation, Ca-citrate, citric acid &#x0D;

Temperature mediates the outcome of species interactions in early life-history stages of two sympatric kelp species

Ocean warming can mediate species interactions and provoke changes in community structure worldwide. Species interactions vary along environmental gradients and life-history stages and increasing temperatures may change competitive dominance between species. Kelps, being marine foundation species, have a complex heteromorphic life cycle, with the early developmental stages being a bottleneck for successful establishment of the adult population. Here, we investigated how temperature influences interactions in early life-history stages of two kelp species with different thermal affinities (Alaria esculenta and Laminaria digitata from Spitsbergen) by cultivating them in mono- and co-culture and different temperatures. Irrespectively of cultivation treatment, spore germination, gametogenesis, and sporophyte development of both species were mostly positively stimulated by a temperature increase from mean ambient summer temperatures (4–5 °C) to a global warming scenario for the Arctic future (9–10 °C) but not at 15 °C which is the southern temperature limit of A. esculenta. At 15 °C gametogenesis and sporophyte formation of A. esculenta were greatly inhibited in monoculture but not so in L. digitata. On the other hand at 5 °C and 10 °C, gametogenesis and sporophyte growth were generally faster in A. esculenta than in L. digitata, leading to a competitive advantage of A. esculenta over L. digitata in the co-cultivation treatments. The interactive effects of co-cultivation and temperature were evident, where development of A. esculenta was accelerated in the presence of L. digitata at 9 °C but not at 4 °C. Although the mechanisms triggering interspecific interactions were not determined in this study, future global warming was found to give competitive advantage of A. esculenta over L. digitata, which could affect community structure and dominance in coastal environments.

Effects of Cultivation Practices and Products on Bermudagrass Fairways in a Semiarid Region

High evapotranspirational demand combined with poor quality irrigation water increases salinity concerns in semiarid regions. Accumulated salts in the root zone may negatively affect bermudagrass (Cynodon spp.) growth and quality. The objective of this study was to examine the effectiveness of cultivation practices combined with products to enhance fairway conditions without applying leaching water levels. Two golf courses in Lubbock, TX, were selected for this research. Cultivation practices, including noncultivated control, core aerification, and slicing, were conducted in mid‐June of 2015 and 2016. Nine products recommended to enhance water movement or to disassociate sodium were applied within each cultivation treatment at label rates. Soil pH and electrical conductivity (EC) were determined from samples obtained in June, August, and October each year. Volumetric water content, visual turf quality, digital image analysis, normalized difference vegetation index, and ratio vegetation index were assessed from June to October in 2015 and 2016. Soil EC fluctuated with rainfall events. However, no treatment reduced soil EC. Gypsum‐based products increased soil EC but reduced pH at the conclusion of the research. Core aerification reduced aboveground parameters at Golf Course A because aerified holes remained visible throughout summer, whereas slicing and core aerification improved turf quality and ratio vegetation index at Golf Course B. These results emphasize the need to test irrigation water for the salinity hazard before implementing management strategies and the importance of leaching by rainfall or additional irrigation. Lastly, high surface disruption cultivation practices may inhibit bermudagrass recovery on higher clay content soils.Core Ideas Rainfall and high ET fluctuated soil EC of bermudagrass golf fairways. Gypsum products increased soil EC and reduced soil pH after 2 yr of applications. Bermudagrass recovery from core aerification was slowed with higher clay content. Cultivation practices improved parameters on high sand content soil after recovery.

Marshland restoration benefits Collembola recruitment: a long-term chronosequence study in Sanjiang mire marshland, China.

To examine the biodiversity restoration of marshlands after human-induced disturbances, a long-term chronosequence study of Collembola communities was completed that included cultivated treatment (marshes with 15 years of soybean cultivation; CU15), two restored treatments (with 6 and 12 years of agricultural abandonment; RE06 and RE12, respectively), and an intact marshland (IM) as a reference in the Sanjiang Plain, Northeastern China. Changes in the soil properties and Collembola communities under different treatments were analyzed. Soil parameters (i.e., soil organic carbon, available N, P and K, soil moisture) significantly increased from the cultivated treatment to the 6-year agricultural abandoned, and then 12-year agricultural abandoned treatment, indicating that the degraded soil began to recover after agricultural abandonment. The density, species richness and diversity of Collembola in RE12 were significantly higher than in RE06 and CU15, and even surpass the IM, indicating marshland restoration (after 12 years of agricultural abandonment) benefited recruitment and reconstruction of Collembola community. We found soil surface-dwelling Collembola recovered faster than eu-edaphic species, that is probably due to some common traits (i.e., parthenogenesis and fast dispersal) between epi- and hemi-edaphic species. The changes in the vegetation and soil properties during long-term soybean cultivation and agricultural abandonment were the key factors affecting the composition, density, and species richness of soil Collembola.

Effects of Soil Tillage and Canopy Optimization on Grain Yield, Root Growth, and Water Use Efficiency of Rainfed Maize in Northeast China

Elucidating the mechanisms underlying the relationships between root growth and water use efficiency is important for achieving full yield potential. We conducted a field experiment with maize under high planting density (105,000 plants ha−1) in 2013 and 2014. Four treatments were implemented: traditional cultivation, root optimization cultivation, canopy optimization cultivation, and shoot–root optimization cultivation. Compared to the treatments involving rotary tillage, subsoil tillage significantly improved the soil structure and promoted soil water storage. Moreover, the distribution of roots was significantly deeper under shoot–root optimization cultivation than traditional cultivation treatment. Shoot dry matter and leaf area were slightly higher under the plant growth-regulator treatments than that under the other treatments. Thus, relative to the shoot–root optimization cultivation treatment, the root optimization cultivation and canopy optimization cultivation treatments reduced the shoot–root area ratio by 8% and 4%, respectively, and these reductions were significantly lower than the reduction under the traditional cultivation treatment (16%). Rainfall storage can be enhanced by improving tillage practices, promoting root growth (particularly at depths &gt;20 cm), promoting access to water, and regulating plant growth by the foliar spraying of ECK (ethylene-chlormequat-potassium). This approach has the potential to achieve highly efficient resource utilization without additional inputs, thereby increasing yield.

Effect of salicylic acid and mycorrhizal symbiosis on improvement of fluoranthene phytoremediation using tall fescue (Festuca arundinacea Schreb)

Polycyclic aromatic hydrocarbons are an important group of pollutants that are widely distributed in the environment. The present study aimed to investigate the effect of salicylic acid (a phenolic phytohormone) and mycorrhizal fungi on the growth and phytoremediation ability of tall fescue in the soil contaminated by fluoranthene. The initial concentrations of fluoranthene in this study were 100, 200, and 300 mg kg-1. The experimental treatments were included: T0 uncultivated soil; T1 cultivated soil with tall fescue; T2 cultivated soil with tall fescue + salicylic acid application; T3 cultivated soil with tall fescue + application of mycorrhizal fungi; T4 cultivated soil with tall fescue + salicylic acid and mycorrhizal fungi application; and P planting tall fescue in uncontaminated soil. The removal of fluoranthene was measured after 90 days. Furthermore, at the end of the experiment, the amount of shoot and root biomass, soil bacteria, and dehydrogenase activity were measured. According to the results, in all levels of contamination, removal of fluoranthene in cultivated treatments significantly was higher than uncultivated treatments. Increasing the concentration of fluoranthene had a negative effect on the shoot and root biomass in different treatments. Salicylic acid and mycorrhizal fungi significantly increased the shoot and root biomass and also the number of soil bacteria, dehydrogenase activity, and fluoranthene removal in T2, T3, and T4 treatments compared to T1. At the highest concentration of fluoranthene, as a result of simultaneous application of salicylic acid and mycorrhizal fungi (T4), the fluoranthene removal increased by 63, 21, 13, and 16% in comparison with T0, T1, T2, and T3, respectively. Based on the results, salicylic acid and mycorrhizal fungi, either alone or in combination, have a significant effect on the improvement of phytoremediation potential in tall fescue.