Sequential Harvests Research Articles

The alteration of interspecific interaction responded to various relative sowing time in wheat/maize intercropping.

An interspecific interaction is an important reason for the yield advantage of interspecific cropping compared with sole cropping, and the relative sowing time of species is an important factor affecting interspecific competitiveness. Our purpose was to explore the effects of different relative sowing times on the interspecific competition-recovery phenomenon in wheat and maize intercropping systems. Three planting methods (wheat/maize intercropping, wheat and maize sole cropping) and different relative sowing times of wheat were used to carry out field experiments over two years. Sequential harvest of subplots was performed between 3 and 6 times, and the biomass data were fitted to logistic growth model. Delaying the sowing time of wheat reduced the wheat yield, biomass and nutrient acquisition and increased those of maize, but wheat still had an intercropping advantage during the co-growth period. At the same time, the nutrient acquisition of maize was still inhibited, but its recovery growth advanced. Changing the relative sowing time of wheat significantly changed the maximum instantaneous growth rates of wheat and maize. Delaying the relative sowing time of wheat significantly reduced its maximum instantaneous growth rate, while enhancing that of maize, leading to a balanced mutual benefit. Delaying the sowing time of wheat to the same sowing time as maize will change wheat/maize intercropping from asymmetrical interspecific facilitation to symmetrical interspecific facilitation. However, in this case, intercropped wheat still had an interspecific competitive advantage in the co-growth stage, and intercropped maize still underwent a competition-recovery process.

Impact of harvest date on aroma compound composition of Merlot and Cabernet-Sauvignon must and wine in a context of climate change: a focus on cooked fruit molecular markers

Choice of harvest date can modulate the aroma intensity of herbaceous/vegetal, fresh fruit and cooked fruit nuances, thus helping the winemaker to produce wine of different styles and balance. Relationships between the sensory attributes and aroma compounds of Merlot and Cabernet-Sauvignon grapes that were harvested sequentially and the resulting wines were evaluated for two vintages: 2012 and 2014. The fine-tuning of the harvest date modulated the aromas of the young wine and impacted the intensity of the cooked fruit aromas for both Merlot and Cabernet-Sauvignon. No correlation was observed between the must and wine in terms of the intensity of the cooked fruit aroma. In order to observe an impact on the intensity of the cooked fruit aroma it was necessary to delay the harvest date of Cabernet-Sauvignon by 4 to 12 days in 2012 and 2014 respectively. This value was 7 days for Merlot wines (2014 vintage). Furanones, lactone and ketones were well correlated with the perceived intensity of the cooked fruit aroma in the young wine. In addition, the highest concentrations of γ-nonalactone, 3-methyl-2,4-nonanedione, massoia lactone and furaneol were detected in Merlot wines made using late-harvested grapes. At the measured concentrations, these compounds can explain the aroma of cooked fruit detected in the red wines. Similar results were obtained for the Cabernet-Sauvignon wines made from grapes from a later harvest. The volatile compounds produced from the lipoxygenase pathway in the grapes were putatively involved in the evolution of the aroma of the red wines from sequential harvest dates, opening up the possibility of managing aroma profiles through harvest date decisions. These findings are important, as the identification of measurable key chemical parameters in grapes could provide grape growers and winemakers objective indicators for predicting final wine style and quality.

Determination in Forage Yield and Quality of Chicory and Different Plants Mixtures in Grazing Maturity Period

This study was conducted to determine forage yield and quality of chicory (Cichorium inthybus L.) in a pure stand and a simple pasture (two-species) in the grazing maturity period. The experiment design was a Randomized Block Design with 3 replications. The experimental site was located on the grounds of the Ondokuz Mayıs University Agricultural Faculty during the 2017 and 2018 growing periods. In this study, chicory (C), orchardgrass (OG), and red clover (RC) were grown as forage plant materials in a rainfed cropping system in North Türkiye. Simple pastures comprised of 80%C + 20%OG, 60%C +40%OG, 40%C + 60%OG, 20%C + 80%OG, 80%C + 20%RC, 60%C + 40%RC, 40%C + 60%RC, 20%C + 80%RC. Five sequential harvests were made when chicory plants reached 25 cm of plant height in both years. The average plant height ranged from 17.3 to 35.6 cm, and 29.1 to 38.3 cm in 2017 and 2018 respectively. The highest fresh forage yield was determined in red clover mixtures (6519-5443 kg/da) in 2017 and 80%C+20%RC mixture (as 7137 kg/da) in 2018. Total dry matter production was ranged from 216 to 1238 and 279 to 1164 kg/da in 2017 and 2018, respectively. In pure stand chicory pasture, dry matter production was evaluated 216 kg/da in 2017 and 908 kg/da in 2018. Considering the calculated area equivalence ratios (LER) of mixed planting plots in both years and in all forms, it was determined that all mixtures were superior to plain plantings (LER≥1).

Trash or treasure: Rhizome conservation during drought

Abstract The role of storage carbohydrates in plant carbon economy is currently disputed as possibly passive accumulation when other resources are limiting growth, or part of a conservative growth strategy as insurance for regrowth and stress response. One indication may be the fate of carbohydrates in senescing rhizomes, as either translocated to be retained in the live and growing end of the rhizome or kept within the senescing rhizome end and lost into the soil for it to decompose. To examine carbohydrate storage in senescing rhizomes, eight rhizomatous species were grown in a split‐pot design with one compartment containing the forward‐growing and younger end of the rhizome and another containing the older end. Both compartments were either watered (control) or the older one was left un‐watered (drought treatment) to trigger rhizome senescence and potential carbohydrate translocation. Plant growth, root traits, and non‐structural carbohydrate types and concentrations were assessed in four sequential harvests. Drought treatment plants had higher rhizome dry matter content. Younger rhizome parts produced higher new rhizome and above‐ground biomass than older rhizome parts. Carbohydrate concentrations in rhizomes remained consistent for both treatments, younger and older rhizome parts, and all harvests, probably because of the translocation of water from the watered to the dry compartment to prevent senescence and rhizome loss. Contrary to expectations, the experimental treatment did not trigger rhizome senescence: plants responded by conserving the rhizome and resources within, rather than by losing their older parts. The invariant composition and concentration of carbohydrates within the rhizome suggest that rhizomes are essential plant organs and the storage carbohydrates they contain are necessary for regrowth after stress. Read the free Plain Language Summary for this article on the Journal blog.

Effect of Shade on Xylem Development of Moringa oleifera (Alrawag) Seedlings

This study investigated the effect of shade as a moderator oflight intensity and temperature on xylem development of seedlings ofMoringa oleifera. Three levels of shade were used: high shade, mediumshade and no shade. Four sequential harvests were carried out monthly forthe seedlings starting from four weeks after seed sowing. Cross sectionswere prepared from the lower and middle parts of the stems at eachharvest and vessel volume fraction, vessel diameters, number of vesselsand volume fraction of lignified cells were measured. The results showedthat the effect of shade was significant on the anatomical variables.Generally, the values of the anatomical variables of the stem wood of theseedlings decreased with increased shade level. The findings indicate theimportance of shade to M. oleifera seedling development and that itshould be considered in nursery conditions.

Hormese induzida por glifosato em cultivares de Urochloa com aplicação sequencial

Abstract Glyphosate is the most widely used herbicide and is responsible for a significant technical/productive advance in world agriculture. Glyphosate drift after its application to control weeds in agricultural fields can stimulate growth and/or productive performance in non-target plants, located adjacent to the treatment, characterizing the hormesis effect. However, the hormesis effect of glyphosate may be different depending on the plant species, its stage of development, and the applied dose. Considering the stimulus of forage biomass production for animal feed, this study aimed to assess the hormesis effect by successive applications of low glyphosate doses to cultivars of the genus Urochloa. The shoot and root productive responses of three grass cultivars (Urochloa brizantha cv. Marandu, U. brizantha cv. Piatã, and U. ruziziensis cv. Ruziziensis) were assessed in pots through leaf applications of subdoses of the acid equivalent (ae) of glyphosate (5.40, 10.80, 21.60, 43.20, and 86.40 g ae ha-1) and a control (no glyphosate application). Four sequential harvests, conducted with a frequency of 21 days in a completely randomized design and a 6 x 3 x 4 factorial arrangement, with three replications, were assessed. Doses equal to or higher than 43.20 g ae ha-1 of glyphosate, applied in two sequential applications impaired the biomass production of the assessed forages. Ruziziensis was the most susceptible cultivar to the phytotoxic effect. Sequential applications of the subdoses 5.40 and 10.80 g ae ha-1 of glyphosate characterized the hormesis effect, promoting the shoot and root biomass production of the forage plants U. brizantha cv. Marandu, U. brizantha cv. Piatã, and U. ruziziensis cv. Ruziziensis.

Policy interventions and competing management paradigms shape the long-term distribution of forest harvesting across the landscape

Industrial economic models of natural resource management often incentivize the sequential harvesting of resources based on profitability, disproportionately targeting the higher-value elements of the environment. In fisheries, this issue is framed as a problem of "fishing down the food chain" when these elements represent different trophic levels or sequential depletion more generally. Harvesting that focuses on high grading the most profitable, productive, and accessible components of environmental gradients is also thought to occur in the forestry sector. Such a paradigm is inconsistent with a stewardship ethic, entrenched in the forestry literature, that seeks to maintain or enhance forest condition over time. We ask 1) how these conflicting paradigms have influenced patterns of forest harvesting over time and 2) whether more recent conservation-oriented policies influenced these historical harvesting patterns. We use detailed harvest data over a 47-y period and aggregated time series data that span over a century on the central coast of British Columbia, Canada to assess temporal changes in how logging is distributed among various classes of site productivity and terrain accessibility, corresponding to timber value. Most of this record shows a distinct trend of harvesting shifting over time to less productive stands, with some evidence of harvesting occurring in increasingly less accessible forests. However, stewardship-oriented policy changes enacted in the mid-1990s appear to have strongly affected these trends. This illustrates both a profit-maximizing tendency to log down the value chain when choices are unconstrained and the potential of policy choices to impose a greater stewardship ethic on harvesting behavior.

Foliar selenium biofortification of broccolini: effects on plant growth and mineral accumulation

ABSTRACT Foliar biofortification is one effective way to alleviate the inadequate intake of selenium (Se) of millions of people worldwide. To evaluate the efficacy of foliar Se application in broccolini (a new hybrid crop variety derived from a cross between kalian cabbage and broccoli), three treatments were tested: 0, 0.05% or 0.10% (w/v) sodium selenate, applied at the early flowering stage. Florets were harvested in four sequential harvests, showing that both yield and nutritional composition were better in the early harvests, producing fewer but heavier and nutrient-richer florets. Although no overall effects on biomass were observed, the increase in total Se concentrations was more than 80- and 170-folds in both root and shoot of 0.05% and 0.10% Se, respectively, and by 270- and 600-fold in the florets. Although boiling resulted in > 50% loss of Se, an intake of 100 g of fresh weight boiled broccolini biofortified with 0.05% Se treatment will provide ~590 μg Se day−1. This amount is in excess of the tolerable upper limit for Se intake. Therefore, whilst broccolini is clearly a good Se accumulator with the potential to be biofortified with Se, lower application rates would need to be determined to be used for human food purposes.

Efficient and Easy Conversion of Human iPSCs into Functional Induced Microglia-like Cells.

Current protocols converting human induced pluripotent stem cells (iPSCs) into induced microglia-like cells (iMGL) are either dependent on overexpression of transcription factors or require substantial experience in stem-cell technologies. Here, we developed an easy-to-use two-step protocol to convert iPSCs into functional iMGL via: (1) highly efficient differentiation of hematopoietic progenitor cells (HPCs) from iPSCs, and (2) optimized maturation of HPCs to iMGL. A sequential harvesting approach led to an increased HPC yield. The protocol implemented a freezing step, thus allowing HPC biobanking and flexible timing of differentiation into iMGL. Our iMGL responded adequately to the inflammatory stimuli LPS, and iMGL RNAseq analysis matched those of other frequently used protocols. Comparing three different coating modalities, we increased the iMGL yield by culturing on uncoated glass surfaces, thereby retaining differentiation efficiency and functional hallmarks of iMGL. In summary, we provide a high-quality, easy-to-use protocol, rendering generation and functional studies on iMGL an accessible lab resource.

No-Touch Sequential Saphenous Venous Harvesting Technique in Off-Pump Bypass Surgery: A Retrospective Study.

BackgroundIn the mid-1990s, the Swedish expert team proposed saphenous vein graft (SVG) harvesting with pedicle tissue. The short-term and long-term patency rates of the great saphenous vein obtained by the no-touch (NT) were higher than those obtained by the conventional (CON). In the past, NT harvesting was mainly used in on-pump coronary artery bypass grafting (CABG), and vein grafts were mostly single vein grafts. In this study, we retrospectively analyzed the safety and effectiveness of sequential vein grafts using NT harvesting in off-pump CABG.MethodsFrom 2017 to 2019, a total of 505 patients were included in the study. There were 150 patients in the NT group and 355 patients in the CON group. After applying propensity score matching (1:1 matching), 148 patients were included in each group. Baseline data, graft patency, post-operative complications, leg wound complications and 1-year major adverse cardiac and cerebrovascular events (MACCEs) were compared between the two groups.ResultsThere was no significant difference in the patency rate of sequential venous grafts between the two groups 1 year after the operation either before [NT: 7.1% (10/141) vs. CON: 11.5% (38/331), p = 0.149) or after matching (NT: 7.1% (10/140) vs. CON: 7.3% (9/124), p = 0.971]. There was no significant difference in the composite clinical endpoint between the two groups either before [NT: 3 (2.3%) vs. CON: 9 (2.8%), p = 1.000] or after matching [NT: 3 (2.3%) vs. CON: 3 (2.5%), p = 1.000]. There were differences in leg wound complications between the two groups both before [NT: 9 (6.9%) vs. CON: 6 (1.9%), p = 0.007] and after matching [NT: 9 (6.9%) vs. CON: 2 (1.7%), p = 0.043].ConclusionsThe application of the NT harvesting in off-pump CABG with sequential vein grafts is safe and effective. NT method has disadvantages in leg wound.

Long-Term Ecosystem Nutrient Pool Status for Aspen Forest Harvest Simulations on Glacial Till and Sandy Outwash Soils

Sandy outwash and glacial till soils compose large amounts of public forestland due to historically poor agricultural yields. The outwash soils have low fertility, poor nutrient retention and are restricted from whole-tree harvesting (WTH) in some states, whereas the glacial till has medium nutrient retention and fertility, and is unrestricted from WTH. To assess the long-term sustainability of harvesting, a nutrient budget was constructed from field measurements, the National Cooperative Soil Survey (NCSS) database, and literature values for stem-only harvesting (SOH) and WTH at a 45-year rotation length and 11 rotations were simulated. The budgets showed that SOH and WTH recovery years, or the time necessary for the inputs to match outputs through leaching and one harvest, exceeded common rotation lengths for both soil types under all weathering scenarios, and the average WTH reduced the total available rotations by one harvest. The large variation in soil nutrient pools and harvest removals complicated the ability to identify the difference between SOH and WTH early in the model, but differences became apparent with sequential harvests. The recovery years were 2–20 times the 45-year rotation length under all weathering rates. Taken together, models in this study bridge the gap between short- and long-term studies and bring into question the sustainability of WTH and SOH practices on nutrient-poor soils.

Genotype, Environment, Year, and Harvest Effects on Fruit Quality Traits of Five Blueberry (Vaccinium corymbosum L.) Cultivars

Blueberries (Vaccinium spp.) comprise a broad range of perennial woody species. Introgression of native species into cultivated germplasm has adapted Vaccinium germplasm to a range of climates and growing conditions for cultivated blueberry. Genetic differences signify phenotypic variance that is observed among blueberry accessions. In addition, variability in geographic and climatic growing conditions between environments or within the same environment across different years may further affect fruit and plant phenotypic expression. As a result, a phenotype is a function of genetic background (G), environment (E), and their interaction (G × E). In addition, other temporally regulated factors such as year (Y) and harvest time (H) impact plant and fruit quality phenotypic variation. Our research aimed to assess the genotypic performance of five blueberry cultivars, including ‘Echota’, ‘O’Neal’, ‘Reveille’, ‘Summit’, and ‘Sunrise’. The selected cultivars were phenotyped for various fruit quality-related traits over two sequential harvests in two years and two locations. Our results indicated that genotype was a significant source of variation for most phenotypic characteristics. Further, the effect of Y × H and G × Y × H significantly affected the majority of studied phenotypic traits. Within the studied genotypes, ‘Reveille’ and ‘O’Neal’ phenotypic stability were consistent across locations and years; additionally, ‘Summit’ phenotypic characteristics were stable across years, environments, and harvests. Clonal plant replicates within a genotype, harvest, and environment, in addition to individual fruit measures, were the most significant sources of variability.

Shifts from complementarity to selection effects maintain high productivity in maize/legume intercropping systems

Abstract Complementarity (CE) and selection effects (SE) have been either invoked to explain the positive diversity–productivity relationship in natural and semi‐natural ecosystems. Few studies have, however, separated selection and complementarity effects in economically valuable intercropping systems, which receive significant nutrient inputs throughout the growing season. We performed a 2‐year field experiment with five cropping systems (i.e. maize/peanut intercropping, maize/soybean intercropping, maize, peanut and soybean monocultures) under different combinations of nitrogen (N) and phosphorus (P) fertilization. Sequential harvest of subplots was performed five times during the growing season and the additive partitioning method was applied to determine complementarity and selection effects in the two intercropping systems. We found that the land equivalent ratio (LER) based on yield was greater than or close to 1 in both maize/soybean and maize/peanut intercropping systems, suggesting yield advantages in these intercropping systems compared to monocultures. The LER of the two intercropping systems without N fertilization was greater in 2018 than in 2017. Nitrogen fertilization reduced the LER of maize/soybean intercropping in 2018, and that of maize/peanut intercropping across 2 years. Nitrogen fertilization had much stronger effects on maize yield than on soybean or peanut yield. Intercropping increased maize yield but decreased soybean and peanut yield. The CE was more important for net biodiversity effects without N fertilization while the SE was more important with N fertilization in the two intercropping systems across 2 years. Phosphorus fertilization impacts on the LER and biodiversity effects were weaker compared to N fertilization. Finally, net biodiversity effects were greater at later growth stages within a growing season. Synthesis and applications. Our study demonstrates how yield advantages of species‐diverse intercropping systems can be maximized either through (a) CE in the absence of N fertilization thanks to complementarity in nutrient use between crops or (b) SE under N fertilization thanks to overyielding of highly productive species (i.e. maize). Yield advantages promoted by CE are more sustainable because they are associated with reduced chemical fertilizer use and greater monetary benefits to farmers. These findings have important implications for the design and management of species‐diverse intercropping food‐production systems.

Performing sequential harvests based on berry sugar accumulation (mg/berry) to obtain specific wine sensory profiles

This study aimed to investigate the possible existence of reproducible aromatic red wine styles, focusing on fresh fruit aromas and mature fruit aromas (i.e., with dark, jammy fruit characteristics) and taking into account both vintage and vineyard.The study was performed on Australian Shiraz and Cabernet‑Sauvignon from three different meso-climate areas and two consecutive vintages. Sequential harvests were carried out based on the plateau of the physiological indicator berry sugar accumulation (mg/berry) in order to obtain fresh fruit and mature fruit wine sensory profiles. There was a predictable aromatic sequence during grape ripening at each of these two distinct maturity stages regardless of grape genotype (variety) and environment (vineyard and vintage). The post-plateau period of berry sugar accumulation was found to be crucial for the evolution of wine aromatic profiles. During this period, wine aromatic and phenolic maturity were uncoupled from technological maturity (i.e., berry sugar concentration). Dimethyl sulfide was found to be the most relevant wine aromatic marker for differentiating the fresh fruit and mature fruit stages irrespective of the variety. Specific cultivar markers with potential sensory contribution were also identified; for example, (Z)‐3‐hexenol, a possible contributor to the aromatic freshness of Shiraz wines from the fresh fruit stage. The evolution of terpenoids appeared to be separate from the dynamics of berry ripening post plateau of fruit sugar accumulation. On the other hand, ester composition was significantly altered during the same ripening period in Shiraz and Cabernet‑Sauvignon wines with a marked grape genotype effect. The results showed that yeast metabolism was also affected by berry ripening evolution from the plateau of berry sugar accumulation onwards.

Changes in the primary and secondary metabolome of male green asparagus (Asparagus officinalis L.) as modulated by sequential harvesting

Rising temperature and solar radiation drive the mobilization and depletion of crown-deposited metabolites harnessed for asparagus spear regeneration during the spring harvest season. We presently examined how successive same-season harvests impact the sensory, nutritive and bioactive composition of select green asparagus genotypes. Soluble carbohydrates were analyzed by HPLC-RI, organic acids and polyphenols by HPLC-DAD and metals by ion chromatography. Higher sugars and lower acids accentuated sweetness and lower polyphenols contributed to reduced astringency at the beginning of the harvest season. This trend was reversed as the season advanced and spear sensory quality was compromised by declining sugars and rising acids; however, functional quality improved as antioxidant capacity increased along with the concentrations of quercetin-3-O-rutinoside (rutin) and ascorbic acid. The compositional changes presently described were uniform across all genotypes examined and thus contribute toward our understanding of seasonal variation in the sensory and functional quality of this acclaimed health-promoting product.

Agronomic iodine biofortification of leafy vegetables grown in Vertisols, Oxisols and Alfisols

Iodine deficiency disorders (IDD) in sub-Saharan African countries are related to low dietary I intake and generally combatted through salt iodisation. Agronomic biofortification of food crops may be an alternative approach. This study assessed the effectiveness of I biofortification of green vegetables (Brassica napus L and Amaranthus retroflexus L.) grown in tropical soils with contrasting chemistry and fertility. Application rates of 0, 5 and 10 kg ha−1I applied to foliage or soil were assessed. Leaves were harvested fortnightly for ~ 2 months after I application before a second crop was grown to assess the availability of residual soil I. A separate experiment was used to investigate storage of I within the plants. Iodine concentration and uptake in sequential harvests showed a sharp drop within 28 days of I application in all soil types for all I application levels and methods. This rapid decline likely reflects I fixation in the soil. Iodine biofortification increased I uptake and concentration in the vegetables to a level useful for increasing dietary I intake and could be a feasible way to reduce IDD in tropical regions. However, biofortification of green vegetables which are subject to multiple harvests requires repeated I applications.

Physiological and Nutraceutical Quality of Green and Red Pigmented Lettuce in Response to NaCl Concentration in Two Successive Harvests

Nutritional eustress such as salinity or nutrient stress applied in soilless systems, is a convenient pre-harvest factor efficient in modulating the phytochemical components of horticultural crops, by triggering defensive mechanisms and accumulating plant secondary metabolites in plants tissues. Nevertheless, genetic material (cultivars with different pigmentation) dictates lettuce metabolites and physiological response to extrinsic eustress, with red leaf cultivars being highly nutrient packed notwithstanding the stress. Product quality can be meliorated equally by applying several cuts, a practice proven to increase bioactive compounds accumulation. In this study, we analyzed the effects of four salinity levels (1, 10, 20 and 30 mM NaCl) on green and red pigmented Salad Bowl lettuce (Lactuca sativa L. var. acephala) in two successive harvests cultivated in a floating raft system. The morphological parameters, mineral composition, leaf gas exchanges, bioactive compounds, and antioxidant activity of both cultivars were assessed. The green cultivar exhibited superior crop productivity but was more prone to salinity effect than the red cultivar. Irrespective of cultivar and cut order, the net photosynthesis decreased with increasing salinity in the nutrient solution. The second cut incurred higher dry biomass, greater accumulation of most minerals and higher photosynthetic activity. In red lettuce, 20 mM NaCl proved adequate eustress to increase phytonutrients and beneficial minerals (K, Ca, and Mg) with minimal loss of yield. Mild salinity and sequential harvest have proven effective pre-harvest tools in positively modulating the quality of lettuce. Eustress interaction with genotype was demonstrated as a promising field for future breeding programs targeting select genotypes for agronomic application of eustress to improve the nutraceutical value of vegetable crops.

Post‐harvest physiological deterioration in several cassava genotypes over sequential harvests and effect of pruning prior to harvest

SummaryConsumers, traders and processors consider post‐harvest physiological deterioration (PPD) an important constraint. In Experiment 1, PPD was assessed three consecutive years in roots from five genotypes through seven storage days. PPD, scopoletin and dry matter content (DMC) was recorded during storage. Year, genotype, duration of storage and their interactions were significant. PPD was associated with duration of storage period, DMC and scopoletin contents. Ambient moisture and temperature during storage influenced PPD. In Experiment 2, roots from seven clones were harvested 10 months after planting from 30 consecutive biweekly plantings. PPD was assessed 0, 2 and 7 days after harvest. In 13 harvests, roots from plants pruned six days earlier were also evaluated. Results indicated large seasonal variation across genotypes. Pruning reduced PPD and DMC. Complex and contrasting relationships among the variables analysed were found. There is no uniform model explaining the relationship between PPD and the independent variables considered.

Doses subletais de glifosato em combinação com manganês foliar na produção de capim marandu

A deriva do herbicida glifosato pode estimular crescimento e/ou rendimento produtivo em plantas não-alvo, caracterizando efeito hormese. Ainda, manifesta-se amarelecimento momentâneo em folhas novas, característico de deficiência nutricional. Deste modo, o trabalho teve por objetivo avaliar o efeito hormese por aplicação de glifosato em Urochloa brizantha cv. Marandu. Foi avaliada a resposta produtiva aérea (PMS) e radicular (MSR) da forrageira por aplicação foliar de sete doses subletais do equivalente ácido (e.a.) de glifosato (5,40, 10,80, 21,60, 43,20, 64,80, 86,40 e 108,00, g e.a. ha-1) e controle, sob ausência e presença de manganês (1000 g ha-1) à calda de pulverização, em quatro colheitas sequenciais, caracterizando esquema fatorial 8 x 2 x 4, com quatro repetições. As doses subletais de glifosato com adição de manganês à calda de pulverização reduziram o efeito herbicida, com persistência de PMS durante período experimental (4 cortes). Para doses sem adição de manganês à calda de pulverização, houve falência produtiva nos cortes 2, 3 e 4, para doses 86,40 e 108,00 g e.a. ha-1. A presença de manganês à calda de pulverização assegurou massa seca de raiz superior àquelas sem adição de manganês, sendo constatado efeito do herbicida nas doses igual e superiores a 43,60 g e.a. ha-1.

Use of aquaculture ponds by globally endangered red-crowned crane (Grus japonensis) during the wintering period in the Yancheng National Nature Reserve, a Ramsar wetland

Conversion of natural wetlands to artificial wetlands is a global phenomenon that leads to loss of natural habitats for waterbirds, while these alternative wetlands may buffer the adverse effects of natural wetlands loss by providing waterbirds with suitable habitats. Yancheng National Nature Reserve (YNNR), a Ramsar wetland in China, is the largest wintering area for the globally endangered red-crowned crane (Grus japonensis). A remarkable part of natural wetlands within the YNNR has been reclaimed into aquaculture ponds in recent decades. In order to better understand the utilization of aquaculture pond by cranes and identify beneficial management actions, we investigated the wintering crane occurrence in ponds and quantified pond characteristics as mainly influence factors from November to March in 2017–2018 and 2018–2019. A total of 198 ponds were measured (91 in 2017–2018 and 107 in 2018–2019), out of which 42 ponds were found to be used by 48 groups of cranes (16 in 2017–2018 and 32 in 2018–2019). Family groups with 2–4 individuals of cranes were mostly encountered (91.7%) of all the group types. Wintering crane abundance in the aquaculture ponds was higher in 2018–2019 (105 individuals) than that in 2017–2018 (59 individuals). Five factors including water depth, species abundance, species richness, structures and distance to road were identified to influence use of ponds by cranes. However, crane occurrence was significantly associated with only water depth. This study recognized aquaculture ponds as a potential habitat for red-crowned crane. Efforts should be channeled into the sustainable development and maintenance of aquaculture ponds. More specifically, we recommended appropriate management practices to benefit wintering cranes by sequential harvesting of aquaculture ponds, maintaining aquaculture ponds in the buffer zone and keeping the water at a low level.