Control Plots Research Articles

Maize Responses to High Night Temperature During Postflowering and Early Grain Filling: Effects on Yield Components, Kernel Growth and Dry Matter Allocation

ABSTRACTWarm night frequency has increased steadily in the last years across maize production regions, but high night temperature (HNT) effects on growth, grain yield and maize dry matter allocation (DMA) to different plant organs remain poorly understood. In this study, we aimed to (i) analyse the DMA among reproductive and vegetative organs, (ii) evaluate the individual kernel weight through its determinants, rate and duration of grain filling and (iii) quantify changes in grain yield per plant and its components due to HNT during the postflowering and early grain‐filling period. Field‐grown maize was subjected to HNT induced by shelters during a 15‐ or 30‐day period after silking, encompassing the postflowering period (HNT15) and extending the heating into early grain filling (HNT30), respectively. The HNT was applied from 1900 to 0700 h while control plots remained at ambient night temperature (ANT). Kernel number per plant was decreased under both temperature regimes (i.e., HNT15 and HNT30); however, significant reductions in grain yield were only observed under HNT30. The DMA during the heating period was differentially affected by the duration of heating. While DMA to the stem was likewise reduced by both heating treatments, the partition to the uppermost ear was only reduced under HNT30. Related to the lack of response to HNT treatments of the rate and duration of grain filling, the individual kernel weight was not reduced. The source‐sink ratio was not affected by HNT, meanwhile, the apparent reserve use was significantly reduced under HNT30. Our results demonstrate that the magnitude of HNT effects is subjected to the duration of the heating period, but also depends on the intensity of heating explored across seasons, especially for kernel number and grain yield.

Soil water consumption along the profile in response to soil water content variations in a black locust plantation with a rainfall exclusion in Loess Plateau

Soil drying is frequently observed in mature forests in water-limited regions, and poses a threat to sustainable development of the ecosystems. Herein, we assessed the effects of rainfall reduction on the water-use characteristics of a black locust (Robinia pseudoacacia) plantation in a sub-humid region of the Loess Plateau, China. Paired plots were established in the plantation, including a treatment with 30 % throughfall exclusion and a control. We comparatively investigated the dynamics of soil water content (SWC) throughout the profile in the two plots after four years of the treatment and determined the contribution of soil water storage (SWS) in each soil layer to water consumption according to the SWS budget. While SWC across the profile in the control plot showed general responses to replenishment and consumption under rainy and dry weather conditions, respectively, the treatment plot had smaller replenishment and consumption in deep layers, causing an aggravated deficiency in SWS and the formation of a temporary dried soil layer (DSL) at a depth of 55–100 cm. The cumulative decrement in SWS during each dry event (consecutive rainless days of ≥ 5-day duration) in the control plot was significantly correlated with SWC at 100–160 cm, suggesting a substantial contribution of water consumption from this layer. However, the treatment plot showed a major contribution to water consumption from the 0–100 cm soil layer during dry events. The vertical distribution of the root system supports these findings, which differed from our hypothesis that deep soil water would be used in response to reduced rainfall input. The distribution of fine root density in the treatment plot was relatively shallower (0–22 and 0–73.1 cm accounting for 50 % and 90 % of fine roots, respectively) than in the control plot (0–31.2 and 0–103.5 cm for corresponding values). These findings indicate that soil water deficiency resulted in the formation of DSL, which hindered water consumption and root development deeper in the soil profile. The severity and recovery of the DSL may be jointly determined by the vertical distribution of SWS and transpiration demand of the plantation. These findings provide insights for water resource management and sustainable development of the plantations in this region.

Energy efficiency of Silphium perfoliatum and Helianthus salicifolius biomass production

Silphium perfoliatum L. and Helianthus salicifolius A. Dietr are perennial herbaceous crops (PHC) that have recently attracted much attention. This study aimed to determine the energy input, the yield energy value, and the biomass production energy efficiency for the two prospective PHC species depending on the type of fertilizer (liquid digestate and mineral fertilizers) and the nitrogen fertilization level (0, 85 and 170 kg ha−1 N) in three consecutive growing years (2019–2021). S. perfoliatum produced a 14.1 % higher biomass yield energy value (142.3 GJ ha−1 y−1 on average) than H. salicifolius. However, the production of S. perfoliatum also required 22.8 % higher mean energy input (11.3 GJ ha−1 y−1) compared to H. salicifolius. As a result, the mean energy ratio for H. salicifolius (15.2) was 8.6 % higher than for S. perfoliatum. The highest energy ratios for H. salicifolius and S. perfoliatum were 29.7 and 22.8, respectively. Liquid digestate and mineral fertilization resulted in an increase in the yield energy value compared to plots with no fertilization, but at the same time, it increased the energy input. Therefore, the energy ratio in control plots was higher compared to the variants with fertilization.

Population of Bemisia tabaci and Incidence of Yellow Disease in Chili Intercropped with Corn

Bemisia tabaci is one of the limiting factors in chili farming, because it can cause damage both directly and indirectly as a vector for the Pepper yellow leaf curl virus (PepYLCV). Intercropping chili with corn is one of the efforts to control B. tabaci. Physically, corn plants are able to withstand the presence of B. tabaci, in addition to producing volatile compounds that are repellent to B. tabaci. This research was conducted to determine the optimal age of corn plants to be intercropped with chili plants. The research was conducted in Pleret District, Bantul Regency by testing five different ages of corn: 2 weeks after planting, 6 weeks after planting, 8 weeks after planting, 10 weeks after planting and control (without intercropping with corn). Weeks after planting are counted from the first day the corn seeds were planted. Yellow sticky trap (YST) was used to determine the presence of B. tabaci population in each treatment plot. YST was tied to bamboo sticks and placed on treatment beds with as many as 2 (two) traps per treatment plot. The distance between the yellow sticky trap and the plant was 30 cm, so the height of the trap was always adjusted according to the height of the plant. Observation of B. tabaci population was carried out every 5 days by counting the number of B. tabaci caught in yellow sticky traps. The results showed that the population of B. tabaci in the chili plots intercropped with corn was lower than that in the control plot, especially at the age of 6 weeks after planting (WAP). However, the intercropping of chilies and corn had no significant effect on the incidence of yellow disease in chilies.

Spatial Distribution Pattern of Response of Quercus Variabilis Plantation to Forest Restoration Thinning in a Semi-Arid Area in China

Plantations are increasing in frequency and extent across the landscape, especially in China, and forest thinning can accelerate the development of late-successional attributes, thereby enhancing plantation stand structural heterogeneity. To quantify the effect of forest restoration thinning on the spatial heterogeneity and the structure of Quercus variabilis plantations, a restoration thinning experiment in a 40-year-old Quercus variabilis plantation by removing trees from the upper canopy level was conducted; two one-hectare sample plots with thinning and a control (i.e., unlogged) were sampled; and geostatistics methods were used to analyze the spatial distribution pattern of the DBH, height, and density of the stand. We found that restoration forest thinning in the Quercus variabilis plantation had a significant impact on the average DBH and tree height of the stand. Meanwhile, the coefficient of variation and structure ratio of the DBH, tree height, and stand density in the thinning plot were larger than those in the control plot. The range and spatial autocorrelation distance of the DBH and stand density in the thinning plot were smaller than those in the control plot, but the fractal dimension showed the opposite trend. The range and spatial autocorrelation distance of tree height in the thinning plot were higher than those in the control plot. These findings suggested that, compared with the control plot, the stereoscopic distribution of the DBH and stand density in the thinning plot fluctuated less and changed gentler, and its spatial continuity was not high but its variation was significant; meanwhile, the stereoscopic distribution of the tree height in the thinning plot was highly fluctuating and changed more significantly, with a strong spatial dependence and strip gradient distribution. Hence, forest restoration thinning could improve the distribution of the DBH and stand density and adjust the spatial heterogeneity of the DBH, tree height, and stand density of Quercus variabilis plantations.

Reduced accrual of mineral-associated organic matter after two years of enhanced rock weathering in cropland soils, though no net losses of soil organic carbon

Enhanced rock weathering (ERW), the application of crushed silicate rock to soil, can remove atmospheric carbon dioxide by converting it to (bi) carbonate ions or solid carbonate minerals. However, few studies have empirically evaluated ERW in field settings. A critical question remains as to whether additions of crushed rock might positively or negatively affect soil organic matter (SOM)—Earth’s largest terrestrial organic carbon (C) pool and a massive reservoir of organic nitrogen (N). Here, in three irrigated cropland field trials in California, USA, we investigated the effect of crushed meta-basalt rock additions on different pools of soil organic carbon and nitrogen (i.e., mineral-associated organic matter, MAOM, and particulate organic matter, POM), active microbial biomass, and microbial community composition. After 2 years of crushed rock additions, MAOM stocks were lower in the upper surface soil (0–10 cm) of plots with crushed rock compared to unamended control plots. At the 2 sites where baseline pre-treatment data were available, neither total SOC nor SON decreased over the 2 years of study in plots with crushed rock or unamended control plots. However, the accrual rate of MAOM-C and MAOM-N at 0–10 cm was lower in plots with crushed rock vs. unamended controls. Before ERW is deployed at large scales, our results suggest that field trials should assess the effects of crushed rock on SOM pools, especially over multi-year time scales and in different environmental contexts, to accurately assess changes in net C and understand the mechanisms driving interactions between ERW and SOM cycling.

The role of mycorrhizal fungi in enhancing fertiliser efficiency in agriculture

The study was conducted to evaluate the impact of mycorrhizal fungi on the yield, biomass and quality of cereals (wheat and maize) in the South of Ukraine. For the experiment, control and experimental plots were selected where mycorrhizal fungi were used to improve plant nutrient uptake. The research process included detailed measurements of yields, biomass and uptake of nutrients such as phosphorus, nitrogen and potassium at different stages of the growing season. The results showed that the use of mycorrhizal fungi increased wheat yields by 15% and corn yields by 18% in the experimental plots compared to the control plots, which was achieved through increased nutrient uptake from deeper soil layers. Wheat biomass increased by 12% and corn biomass by 14%, indicating a positive impact of mycorrhiza on plant development. Phosphorus uptake at a depth of 20-30 cm increased by 50%, which contributed to better root development and the supply of available elements to plants. In addition, we recorded a 7% increase in protein content in wheat grain and a 9% increase in corn, which indicates an improvement in the nutritional and feed value of the products. The analysis also showed a 4% increase in the oil content of corn grain, which increases its economic value. Another important result was a 15% reduction in mineral fertiliser costs due to improved nutrient use efficiency, which reduces the need for additional fertiliser. The results confirm that the use of mycorrhizal fungi is an effective method for increasing yields, product quality and economic efficiency of agricultural production

Regeneration of post‐mining and post‐fire soil function by assessment of tree nutrient status: Evidence from pioneer and N‐fixing species

AbstractNutrient concentrations in the foliage of particular tree species can identify growth‐limiting factors. Therefore, the adaptability and usefulness of certain trees in the afforestation of barren soils after disturbances could be based on nutrient supply and stoichiometry. In this study, we investigated the macronutrient supply to (i.e., nitrogen [N], phosphorus [P], potassium, sulfur, calcium [Ca], and magnesium [Mg]) and C:N:P (carbon:nitrogen:phosphorus) stoichiometry of the foliage of black alder (Alnus glutinosa), common birch (Betula pendula), and Scots pine (Pinus sylvestris) in two different regeneration scenarios—a reclaimed mine site with primary succession and an afforested post‐fire (PF) site with secondary succession. The control plot was on an undisturbed forest site hosting stands of the studied tree species. The lower concentrations of elements in the post‐mining soils developed from “point zero” were enough to supply the trees with a similar level of nutrition to those in the PF and undisturbed soils. The studied tree species differed in their foliage chemistry and had different effects on the soil properties. The alder and birch foliage contained more nutrients than the pine foliage. In particular, the birch foliage contained the highest concentrations of Ca, Mg, and P, thus enhancing the biogeochemical cycling of these elements. The alder foliage had the highest N concentration, albeit the soil total N contents under this species were not higher than those under birch. Thus, its phytomeliorative effect may have been overestimated. The pine foliage contained the lowest concentrations of nutrients, indicating the high nutrient use efficiency of this species. On the sites degraded after disturbance, pine and birch grew under N‐limitation stress, while the alder—a N‐fixing species—grew under P‐limitation stress, especially at the PF site. The PF soils under alder were also characterized by higher acidity, P depletion, and higher C:P and N:P ratios compared to the PF soils under the other studied species. We found that birch should be the most common tree species in the first phase of area regeneration after disturbances. Introducing alder into afforestation should take place in admixtures, especially at the PF site.

Analysis of the Consequences of a Mixture of Micronutrients on the Parameters Associated with Wheat Growth and Yield

The field experiments were conducted at the agriculture farm of BFIT Crop Research Centre, Dehradun, Uttarakhand, during 2021–22 on the title- “Analysis of the consequences of a mixture of micronutrients on the parameters associated with wheat growth and yield”. A RBD (Randomized Block Design) of plot with eight treatments and three replications was used in this study. The experimental treatments included: T1 - Control (without fertilizer or any other growth activity), T2 - RDF (NPK) only, T3 - RDF (NPK) + Local Formulation(LF) Grade V 10kg/ha mixture of micronutrient on Soil Application (SA) only, T4 - RDF (NPK) + Local Formulation (LF) GradeV 10kg/ha mixture of micronutrient on Soil Application (SA) + 0.25% FS of micronutrient mixture @ tillering stage only,T5 - RDF(NPK) + Local Formulation (LF) Grade V 15kg/ha mixture of micronutrient on Soil Application (SA) only,T6 - RDF(NPK) + Local Formulation (LF) Grade V 15kg/ha mixture of micronutrient on Soil Application (SA) + 0.25 % FS @ tillering stages only, T7 - RDF (NPK) + Local Formulation(LF) GradeV 25kg/ha mixture of micronutrient on Soil Application (SA) only, T8 - RDF (NPK) + Local Formulation (LF) Grade V 25kg/ha mixture of micronutrient 0.25% Foliar Spray (FS) of micronutrient mixture @ tillering stage only. Significant 0.5% increases in spike length, spikelets/spike, spike/m2, number of tillers/m2, number of grains/spike, 1000-grain weight, grain, straw, and biological yields (ton)/fed were noted in the study's results. Additionally, the harvest index was found to be significantly higher in T8 only. The highest grain yield was achieved by T8 while lower yield of growth attributes / parameters was found in the control plot.

Assessment of major insect pests of golden melon (Cucumis melo L.) and control with commercial Beauvaria bassiana in Abeokuta Southwestern, Nigeria

Pest infestation is a major challenge in production of golden melon, this study evaluated the performance of Beauvaria bassiana, a non-residual bio-pesticide, for effectiveness against insect pests of golden melon. The field experiment was carried out in 2022 to establish the effect of B. bassiana sprayed at different growth stages on the abundance of insect pests, damage, agronomic characteristics and fruit quality of golden melon. The results showed Aulacophora spp., Aphis gossypii, Epilachna chrysomelina, Bemisia tabaci Coridius viduatus and Zonocerus variegatus as the insect pests attacking golden melon in the study area. However, the population densities of Aulacophora spp. and E. chrysomelina were significantly lower in golden melon sprayed with B. bassiana at all compared to other spray treatments and the control. Percentage leaf damage and yield loss (20.81% and 327.70 g) in golden melon sprayed with B. bassiana at all stages were similar to lambda-cyhalothrin-sprayed plot (13.68 % and 318. 70 g). Also, highest percent leaf damage and yield losses (81.54 % and 1395.70 %) were obtained in the control plots relative to other spray treatments. Number of leaves and percentage increase in vine length were significantly higher in the golden melon sprayed with B. bassiana at all stages. There was 215.80 % increase in yield of golden melon sprayed with B. bassiana at all stages over the control in the study. Also, the nutritional composition of the fruits from the untreated plots was similar to that of the treated plots

The effects of organic waste materials on Miscanthus × giganteus yield and Zn and Ni content

The aim of the experiment was to determine the yield of Miscanthus × giganteus M 19 in the first three years of cultivation and its bioaccumulation of Zn and Ni in aboveground and underground parts in response to different doses of sewage sludge and substrate left after the production of white mushrooms. Miscanthus × giganteus is a grass species that adapts to different environmental conditions and can be grown in various climatic zones of Europe and North America. In April 2018 the experiment was established in a randomized block design and with four replications in central-eastern Poland. Waste organic materials (municipal sewage sludge and mushroom substrate) were applied to the soil in 2018 in the spring before the rhizomes of giant miscanthus were planted. Each year (from 2018 to 2020) biomass was harvested in December. The yield of fresh and dry matter and the total content of Zn and Ni, after wet mineralization of plant samples, were determined by optical emission spectrometry (ICP-OES). After the third year of cultivation, the content of Zn and Ni in rhizomes and in the soil was determined again. In relation to control, an increase in the yield of miscanthus biomass in response to organic waste materials was noted. Plants responded to mushroom substrate (SMS) with the highest average yield (16.89 Mgha−1DM), while on the control plot it was 13.86 Mg ha−1DM. After the third year of cultivation, rhizomes of Miscanthus x giganteus contained higher amounts of Zn (63.3 mg kg−1) and Ni (7.54 mg kg−1) than aboveground parts (40.52 and 2.07 mg kg–1), which indicated that heavy metals were retained in underground parts.

The dynamics of heavy metals and metalloids accumulation in oxbow bottom sediments of the Sok River

The article analyzes the dynamics of heavy metals (V, Cr, Mn, Co, Ni, Cu, Zn, Rb, Sr, Cd, Pb) and metalloids (As, Se) accumulation in the bottom sediments of the low-flow oxbow of the Sok River. This oxbow was formed as a result of the Saratov reservoir creation and located within the Krasnoglinsky District of the Samara city. The study was conducted in 2021 and 2022. Four trial plots were established in the oxbow of the river; the control plot was a sample area allocated in the Saratov reservoir, in the immediate vicinity of the oxbow. The quantitative determination of heavy metals and metalloids content in bottom sediments was carried out using inductively coupled plasma spectrometry. The results obtained showed that specific conditions arise in each research period that affect the studied elements accumulation in the oxbow bottom sediments. These processes are influenced by the location of the sample plot in the oxbow, the flow degree, the spring flood nature, the anthropogenic transformation and the overgrowth of Typha angustifolia L. For all sample plots located in the oxbow, higher concentrations of most of nalyzed elements were detected in 2022. Heavy metals and metalloids accumulated especially actively in the bottom sediments of sample plot 4, located in the oxbow behind an artificial dam and characterized by the weakest flow. The soil cover of Samara city posesses weak and moderate effect on the quantitative characteristics of metal accumulation in the oxbow bottom sediments. Compared to the control, the studied elements accumulated more actively in the bottom sediments of all oxbow sample areas, which confirms the accumulative nature of river oxbow of varying degrees of isolation.

Exogenous application of plant bio-regulators improve yield and water use efficiency of maize under drought stress

Moisture stress in rainfed areas has significant adverse impact on plant growth and yield. Exogenous application of plant bio-regulators (PBRs) plays an important role to mitigate drought stress in plants. A field experiment was conducted during rainy (kharif) seasons of 2018 and 2019 to explore the positive role of PBRs on the yield, economic feasibility and water use efficiency of maize grown under rainfed conditions. Ten treatments including PBRs, mulching and control were evaluated in a randomized block design. The result showed that foliar spray of salicylic acid (0.5 mM) with 1% urea solution improved the grain yield of maize by 24% as compared to control plot. Other PBRs such as glycine betaine, gibberellic acid and thiourea also increased the grain yield in the range of 10–21%. Application of 1% urea solution with PBRs synergise the effect of PBR to alleviate drought stress. The foliar applied PBRs maintained higher membrane stability index (73–78%), significantly increased relative water content (5–11%), chlorophyll content and decreased the proline content (11–21%) as compared to plants grown in control plot. Significant increase were noted in the rain and crop water use efficiency of maize with the foliar application of PBRs. Net returns were improved by 33% with application of salicylic acid (0.5 mM) + 1% urea as compared to control (₹49 × 103 /ha). Thus, foliar spray of salicylic acid (0.5 mM) with 1% urea solution could be an economic feasible strategy to reduce the adverse effects of drought and may increase the maize yield and water use efficiency.

Foliar spray of glycine-chelated zinc (Zn) and iron (Fe) lowered the effect of macronutrient deficiencies and enhanced rice yield components, yield, and grain biofortification

The current investigation amid the alleviating of the macronutrient [Nitrogen (N), Phosphorus (P), and Potassium (K)] deficiency effects on rice yield, yield components, and grain biofortification by foliar spraying of Zn and Fe chelated by glycine amino acid (ZFCG) on the flooded rice conditions. Three-factor factorial experiment was conducted based on a randomized complete block design with three replications. The experimental factors were: macronutrients [Nitrogen (N), Phosphorous (P), and Potassium (K)] soil application at two levels (100 and 50% of the recommended dose) and foliar application of ZFCG during the booting and ripening stages at three levels (0, 1, and 1.5 kg ha−1). The results clearly showed that the foliar spraying of 1.5 kg ha−1 ZFCG significantly increased the growth characters, yield attributes, yields, and white rice nutritional quality of Hashemi cultivar both at the application of 100% (normal condition) and 50% (nutrient stresses condition) of the recommended rate of NPK. The foliar application of 1.5 kg ha−1 ZFCG increased the rice grain, straw, biological yield, head rice yield, and harvest index of the plots that received 50% of the recommended rate by about 14.6, 10.12, 50, 7.5, and 6.7% compared to the values of the control plots (no adding the NPK), respectively and 49.25, 31.21, 31.60, and 16.67% at the plots that received 100% of recommended NPK, respectively. Moreover, the foliar application of glycine amino acid-Fe and Zn chelate at two vital rice growth stages increased the value of the Zn, Fe and protein content of white rice at the plots that received 1/2 of the recommended dose of NPK by about 52.37%, 2 times, and 8.64% compared to control plots, respectively, and also 20.77%, 2 times, and 12% at the plots that received 100% of recommended NPK, respectively. The observed values are close to their values in those plots that have received 100% of recommended rate of NPK without foliar application. Therefore, it can be concluded that the foliar co-application of 1.5 kg ha−1 ZFCG during the two important rice growth stages (booting and ripening) might both alleviate the improper and imbalanced macronutrient deficiency stresses and enhance the rice grain yield and biofortification at flooded rice cultivation.

Nutrient leaching potential along a time series of forest water reclamation facilities in northern Idaho

Forest water reclamation is a decades-old practice of repurposing municipal reclaimed water using land application on forests to filter nutrients and increase wood production. However, long-term application may lead to nutrient saturation, leaching, and potential impairment of ground and surface water quality. We studied long-term effects of reclaimed water application on nutrient leaching potential in a four-decade time series of forest water reclamation facilities in northern Idaho. Our approach compared reclaimed water treated plots with untreated control plots at each of the forest water reclamation facilities. We measured soil nitrifier abundance and net nitrification rates and used tension lysimeters to sample soil matrix water and drain gauges to sample from a combination of matrix and preferential flow paths. We determined nutrient leaching as the product of soil water nutrient concentrations and model-estimated drainage flux. There was more than 450-fold increase in nitrifier abundance and a 1000-fold increase in net nitrification rates in treated plots compared with control plots at long-established facilities, indicating greater nitrate production with increased cumulative inputs. There were no differences in soil water ammonium, phosphate, and dissolved organic nitrogen concentrations between control and effluent treatments in tension lysimeter samples. However, concurrent with increased nitrifier abundance and net nitrification, nitrate concentration below the rooting zone was 2 to 4-fold higher and nitrate leaching was 4 to 10-fold higher in effluent treated plots, particularly at facilities that have been in operation for over two decades. Thus, net nitrification and nitrifier abundance assays are likely indicators of nitrate leaching potential. Inorganic nutrient concentrations in drain gauge samples were 2 to 11-fold higher than lysimeter samples, suggesting nutrient losses occurred predominantly through preferential flow paths. Nitrate was vulnerable to leaching during the wet season under saturated flow conditions. Although nitrogen saturation is a concern that should be mitigated at long-established facilities, these forest water reclamation facilities were able to maintain average soil water nitrate concentrations to less than 2 mg L−1, so that nitrogen and phosphorous are effectively filtered to below safe water standards.

40 years of forest dynamics and tree demography in an intact tropical forest at M’Baïki in central Africa

A vast silvicultural experiment was set up in 1982 nearby the town of M’Baïki in the Central African Republic to monitor the recovery of tropical forests after disturbance. The M’Baïki experiment consists of ten 4-ha Permanent Sample Plots (PSPs) that were assigned to three silvicultural treatments in 1986 according to a random block design. In each plot, all trees with a girth at breast height greater than 30 cm were spatially located, numbered, measured, and determined botanically. Girth, mortality and newly recruited trees, were monitored almost annually over the 1982–2022 period with inventory campaigns for 35 years. The data were earlier used to fit growth and population models, to study the species composition dynamics, and the effect of silvicultural treatments on tree diversity and aboveground biomass. Here, we present new information on the forest stand structure dynamics and tree demography. The data released from this paper cover the three control plots and constitute a major contribution for further studies about the biodiversity of intact tropical forests.

Response of soil microbial diversity and functionality to snow removal in a cool-temperate forest

Climate-induced changes in thinning snowpack can greatly impact soil freeze-thaw patterns and water supply. These effects may influence the soil microbial diversity and the key ecological functions mediated by microorganisms, thereby altering the cycling of nutrient in the ecosystem. A snow-exclusion experiment to explore the effects of snow removal on soil microbial diversity and functionality in Larix gmelinii forest. Control (natural snowfall), SR (complete snow removal) and SR-SR (complete snow removal, with snow returned for water supplementation at the end of winter) were represented three experimental treatments. The results showed that: snow removal resulted in more severe soil frost in winter. Soil nitrogen availability was higher in the snow removal plots compared to control plots in freeze-thaw period. Fungal diversity was not affected by snow removal, neither the α diversity of bacteria. However, snow removal did alter the bacterial community structure. These changes of the above did not persist into the growing season. SR-SR significantly reduced soil multifunctionality during freeze-thaw period, whereas SR did not. However, SR and SR-SR resulted in significantly higher soil multifunctionality than was observed in control during early growing season. Additionally, a widespread increase in the abundance of nitrogen cycling genes was observed in the SR and SR-SR plots during the freeze-thaw period and the early growing season, respectively. Snow removal significantly affected soil multifunctionality, which can be explained by changes in the microbial biomass, bacterial community structure and network complexity. Furthermore, snow removal significantly altered soil water content, temperature, and dissolved carbon, nitrogen. dbRDA and random forest analysis showed that soil water content, temperature, and total nitrogen as drivers of soil microbial community structure and multifunctionality. This study highlights that snow removal altered soil nitrogen availability, microbial community diversity, and multifunctionality during freeze-thaw period. However, these changes did not result in cross-seasonal legacy effects.

Field Efficacy and Economics of Certain Biopesticides and Chemicals against Gram Pod Borer, Helicoverpa armigera (Hubner) on Greengram [Vigna radiata (L.) Wilczek

In the kharif season of 2023–2024, a field experiment was carried out at the in Eight treatments—Spinosad 45SC, Ha NPV 1X109ml/min, Neem seed kernel extract 10% WP, Emamectin Benzoate 5%SG, Azadirachtin (Neem oil) 0.03% WSP, Chlorantraniliprole 18.5SC, Bacillus thuringienssis 4% WSP, and untreated Control—were used in the RBD experiment. Each treatment was replicated three times. After the first and second sprays, data on the Helicoverpa armigera larval population showed that all treatments were much beter than the control. Following Chlorantraniliprole (18.5%SC) (0.323) as the least amount of larvae was recorded among all the treatments, Spinosade (45%SC) (0.456), Emamecttin benzoate (5%SG) (0.578), Azadirachtin (Neem oil) 00.03%EC (0.712), Neem seed kernel extract (10% The highest documented larval population in this case was 1x108CFU (1.112) of Bacillus thuringiensis. However, the treatment that produced the best yield (15.36 q/ha) was chlorantraniliprole 18.5% SC. An intriguing outcome was obtained when the cost-benefit ratio was calculated. The study found that, when compared to a control plot of 1:1.04, the most effective and cost-effective treatment was Chlorantraniliprol 18.5 SC (1:3.65), followed by Spinosade 45% SC (1:3.26), Emamectin benzoate 5% SG (1:2.94), and Azadirachtin (Neem oil) 00.03%EC (1:1.89), Neem seed kernel extract 10% WP (1:1.92), Ha NPV 1X109 POB ml/min (1:1.62), and Bacillus thuringiensis 1x108CFU (1:1.58).0.978, 1X 109 POB/ml/min. WP) (0.845), and Ha NPV 1X 109 POB/ml/min (0.978) were the next five treatments.

Pre-emergence herbicides mixture in soybeans: Amaranthus hybridus control and crop selectivity on cover crops soil

The objective was to evaluate the efficacy of pre-emergence herbicides mixture applied to the soil with and without dead cover crops (Sorghum bicolor) for the control of Amaranthus hybridus L. (smooth pigweed) and its selectivity in soybeans. This study was structured in split plot (2 × 6 + 2), where factor A plots (with and without dead cover) and factor B six herbicides mixture: flumioxazin + S-metolachlor (50.4 + 1,008 g a.i. ha−1), flumioxazin + imazethapyr (60 + 127.2 g a.i. ha−1), pyroxasulfone + sulfentrazone (137.6 + 160 g a.i. ha−1), diuron + sulfentrazone (400 + 200 g a.i. ha−1), metribuzin + S-metolachlor (326.4 + 1,344 g a.i. ha−1) and sulfentrazone + imazethapyr (200 + 100 g a.i. ha−1) and two untreated control plots. As for the results, the herbicides flumioxazin + S-metolachlor, flumioxazin + imazethapyr and pyroxasulfone + sulfentrazone showed excellent control (97–99%) and were not influenced by the plot with and without dead cover. They also showed higher yield soybeans (<2,244 kg ha−1). All herbicides were selective to the soybeans. Overall, pre-emergence herbicides and cover crops were efficient methods for the control of A. hybridus, which farmers should use to avoid losses in yield soybeans due to weed competition.

Forest floor environment overrules global change treatment effects on understorey communities in a mesocosm experiment.

Light availability profoundly influences plant communities, especially below dense tree canopies in forests. Canopy disturbances, altering forest floor light conditions, together with other environmental changes such as climate change, nitrogen deposition and legacy effects from previous land-use will simultaneously impact forest understorey communities. Yet, knowledge on the individual effects of these drivers and their potential interactions remains scarce. Here we performed a forest mesocosm experiment to assess the influence of warming, illumination (simulating canopy opening), nitrogen deposition and soil land-use history (comparing ancient and post-agricultural forest soil) on understorey community composition trajectories over a 7-year period. Strikingly, understorey communities primarily evolved in response to the deeply shaded ambient forest conditions, with experimental treatments exerting only secondary influences. The overruling trajectory steered all mesocosms towards slow-colonizing forest specialist communities dominated by spring geophytes with lower nutrient-demand. The illumination treatment and, to a lesser extent, warming and agricultural land-use legacy slowed down this trend by advancing fast-growing resource-acquisitive generalist species. Warm ambient temperatures induced thermophilization of plant communities in all treatments, including control plots, towards higher dominance of warm-adapted species. Nitrogen addition accelerated this thermophilization process and increased the community light-demand signature. Land-use legacy effects were limited in our study. Our findings underscore the essential role of limited light availability in preserving forest specialists in understorey communities and highlight the importance of maintaining a dense canopy cover to attenuate global change impacts. It is crucial to integrate this knowledge in forest management adaptation to global change, particularly in the face of increasing demands for wood and wood products and intensified natural canopy disturbances.