Higher Fertilization Rate Research Articles

Oxidative stress and DNA damage status in couples undergoing in vitro fertilization treatment.

SummaryThis study examined the status of oxidative stress in 599 couples undertaking in vitro fertilization (IVF) treatment and its association with reproductive hormones, smoking, and outcomes. Oxidative stress biomarkers such as malondialdehyde, 8-hydroxy-2-deoxyguanosine, hydrogen peroxide (H2O2), catalase (CAT), and total antioxidant capacity (TAC) were determined in follicular fluid and seminal plasma. Tail moment (TM) was used to evaluate DNA damage in the sperm and granulosa cells. Reproductive hormones in serum and cotinine (COT) in urine, follicular fluid, and seminal plasma samples were determined. Separate multivariate linear regression was used to assess associations between levels of each oxidative stress biomarker and each hormone and smoking parameter (modeled as natural log-transformed). The findings indicate that some oxidative stress and DNA damage biomarkers played a role in disrupting certain reproductive hormones in women and their male partners either by overproducing reactive oxygen species or reducing antioxidant defense capacity. Although women were nonsmokers, COT levels > 50 and 10 µg/L in urine and follicular were observed in 5.7 and 1.7%, respectively. Levels of follicular fluid COT were positively associated with H2O2 and TM. We used log-binomial multivariate regression to estimate relative risks for the association between oxidative stress/DNA damage and IVF binary outcomes (fertilization rate > 50%, biochemical pregnancy, clinical pregnancy, and live birth). An increase in the CAT levels of follicular fluid was associated with a 48 and 41% decrease in the risk of poor fertilization rate (≤50%) and unsuccessful live birth, respectively. After the models were adjusted for hormonal factors, the associations remained the same, except that the elevated TAC in follicular fluid became significantly associated with a decrease of 42% in the risk of poor fertilization rate (≤50%). The higher antioxidant activity (CAT and TAC) in follicular fluid might positively impact specific IVF outcomes.Lay summaryOxidative stress occurs when antioxidant molecules are insufficient in the body to destroy free radicals that can damage the cells, proteins and DNA, causing different health conditions, including infertility. The role of oxidative stress in female infertility has not received as much attention as male infertility, and research is still limited. This study explored whether the overproduction of free radicals can impact the success of in vitro fertilization (IVF) treatment using several biological markers such as hydrogen peroxide, catalase, and total antioxidant capacity. Our findings revealed that the high antioxidant levels in the fluid surrounding the egg were linked with a high fertilization rate. Additionally, oxidative stress status in couples was associated negatively with several reproductive hormones and smoking status. Biomarkers of oxidative stress and DNA damage might have potential applications in evaluating IVF patients’ clinical characteristics such as causes of infertility, hormonal profile, fertilization rate, implantation and live birth.

Mulching with pruned fronds promotes the internal soil N cycling and soil fertility in a large-scale oil palm plantation

Intensive management practices in large-scale oil palm plantations can slow down nutrient cycling and alter other soil functions. Thus, there is a need to reduce management intensity without sacrificing productivity. The aim of our study was to investigate the effect of management practices on gross rates of soil N cycling and soil fertility. In Jambi province, Indonesia, we established a management experiment in a large-scale oil palm plantation to compare conventional practices (i.e. high fertilization rates and herbicide weeding) with reduced management intensity (i.e. reduced fertilization rates and mechanical weeding). Also, we compared the typical management zones characterizing large-scale plantations: palm circle, inter-row and frond-stacked area. After 1.5 years of this experiment, reduced and conventional management showed comparable gross soil N cycling rates; however, there were stark differences among management zones. The frond-stacked area had higher soil N cycling rates and soil fertility (high microbial biomass, extractable C, soil organic C, extractable organic N, total N and low bulk density) than inter-row and palm circle (all p ≤ 0.05). Microbial biomass was the main driver of the soil N cycle, attested by its high correlation with gross N-cycling rates (r = 0.93–0.95, p < 0.01). The correlations of microbial N with extractable C, extractable organic N, soil organic C and total N (r = 0.76–0.89, p < 0.01) suggest that microbial biomass was mainly regulated by the availability of organic matter. Mulching with senesced fronds enhanced soil microbial biomass, which promoted nutrient recycling and thereby can decrease dependency on chemical fertilizers.

Agronomic Efficiency of Animal-Derived Organic Fertilizers and Their Effects on Biology and Fertility of Soil: A Review

Healthy soils are essential for progressive agronomic activities. Organic fertilization positively affects agro-ecosystems by stimulating plant growth, enhancing crop productivity and fruit quality and improving soil fertility. Soil health and food security are the key elements of Organic Agriculture 3.0. Landfilling and/or open-dumping of animal wastes produced from slaughtering cause environmental pollution by releasing toxic substances, leachate and greenhouse gases. Direct application of animal carcasses to agricultural fields can adversely affect soil microbiota. Effective waste management technologies such as thermal drying, composting, vermicomposting and anaerobic digestion transform animal wastes, making them suitable for soil application by supplying soil high in organic carbon and total nitrogen. Recent agronomic practices applied recycled animal wastes as organic fertilizer in crop production. However, plants may not survive at a high fertilization rate due to the presence of labile carbon fraction in animal wastes. Therefore, dose calculation and determination of fertilizer application frequency are crucial for agronomists. Long-term animal waste-derived organic supplementation promotes copiotrophic microbial abundance due to enhanced substrate affinity, provides micronutrients to soils and protects crops from soil-borne pathogens owing to formation of plant-beneficial microbial consortia. Animal waste-derived organically fertilized soils possess higher urease and acid phosphatase activities. Furthermore, waste to fertilizer conversion is a low-energy requiring process that promotes circular bio-economy. Thus, considering the promotion of soil fertility, microbial abundance, disease protection and economic considerations application of animal-waste-derived organic fertilizer should be the mainstay for sustainable agriculture.

Fertilization and Shading Trials to Promote Pinus nigra Seedlings’ Nursery Growth under the Climate Change Demands

Pinus nigra is one of the most widely used tree species for reforestation within its geographical distribution, as well as being a potential substitute for other tree species in Central Europe under future climate scenarios. P. nigra is transplanted into the field as two-year or three-year old seedlings because of its relatively low growth rate in the nursery. This study investigated the effects of fertilization programs and shading on P. nigra seedlings, aiming to accelerate early growth, and thus to reduce the nursery rearing time. The experiment (a completely randomized block design) was conducted in an open-air nursery by sowing seeds from Grevena, Northern Greece, in Quick pots filled with peat and perlite in a 2:1 ratio. The seedlings were subjected to two levels of fertilization—5 and 10 g L−1 NPK (30-10-10)—and two shading levels: 50% and 70%. At the ends of the first and second nursery growing season, we recorded the seedlings’ above- and below-ground morphology and biomass data. The results show that the application of all of the treatments produced seedlings which met the targeted quality standards for outplanting. However, the combination of a high fertilization rate and low shading level resulted in seedlings of a higher morphological quality, which is often considered to be an indicator for a successful seedling establishment in the field.

The evaluation of culture performance and mantle coloration of two boring giant clam (Tridacna crocea) strains

The boring giant clam (Tridacna crocea) is the smallest species of the Tridacna genus, but they strongly express mantle color polymorphism. These color morphs represent potential genetic resources for aquaculture to supply the aquarium market, and the evaluation of their genetic and production characteristics is important. Wild yellow-green clams were consistently larger than blue clams in both the Huangyan Island and Zhaoshu Island populations in the Southern China Sea. To determine the relationship between mantle color and phenotypic traits, blue, yellow-green and control strains (various colors) were constructed and cultured for 1.5 years at an experimental station in Sanya, Hainan Island Province. All three strains had a high fertilization rate, but the survival to D larvae of the blue strain was significantly lower than the other two strains. Larval survival rate was over 85 % for all three strains, but the metamorphosis rate of the control strain was significantly lower than that of the other two strains. During the grow-out stage, the survival rate of the control strain from day 120 to day 480 was highest and that of the blue strain was lowest of the three groups. After metamorphosis, growth divergence of the three strains varied until day 120. Consistent growth trends appeared from day 120 to day 180, with the yellow-green strain largest, followed by the control strain. The process of mantle coloration was divided into three stages: the non-coloring period (day 0–60), the coloring period (day 60–180), and the stable expression period (day 180 onward). The yellow-green and blue mantle colors are genetically stable. This study provides a base for analysis of mantle color heredity and the genetic breeding of giant clams, and has great potential applications in the aquaculture industry, aquarium market and the coral reef tourism.

Low-input cultivation of camelina (&lt;em&gt;Camelina sativa&lt;/em&gt; (L.) Crantz) in a Mediterranean semi-arid environment

The cultivation of oil crops for biofuel production has often been accused of not being environmentally sustainable due to the high inputs needed. To explore the effect of reduced input on productive and qualitative traits of camelina (Camelina sativa (L.) Crantz), a trial was carried out over a two-year period. This study analysed two different levels of input: a low input treatment (shallow non-inversion tillage and low fertilisation rate) and a high input treatment (deeper tillage and high fertilisation rate). Camelina was positively, even though to a limited extent, affected by high input treatment as highlighted by the increase in seed yield (from 1.8 to 2.0 t ha–1), crop residues (from 4.8 to 5.2 t ha–1), seed protein content (from 26.5 to 28.9%), seed oil content (from 41.5 to 43.4%) and oil yield (from 0.75 to 0.88 t ha–1). So, from a sustainable point of view, we must consider negligible the effect of high input and satisfactory the performances of camelina in the low input regime. Low input management resulted in satisfactory yields in terms of both quantity and quality, results which were not very different from high input, indicating promising potential for conservation agriculture practices in camelina in a semi-arid environment.&#x0D; Highlights - Camelina showed high adaptability to conservation agriculture practices. - Seed yield of 1.9 t ha–1 was obtained under reduced tillage and low fertilisation rate. - High inputs (fertilisation and tillage) determined a 12-d longer crop cycle. - α-linolenic, erucic and eicosenoic acids were affected by input levels.

Zeolite and Vermiculite as Inorganic Soil Amendments Modify Shoot-Root Allocation, Mineral Nutrition, Photosystem II Activity and Gas Exchange Parameters of Chestnut (Castanea sativa Mill) Plants

One of the most challenging topics for the sustainable agriculture is how to decrease high fertilization rates. A pot experiment, exploring the effects of zeolite (ZEO) and/or vermiculite (VER) as soil amendments, comparing to the soil application of a controlled release fertilizer (CRF), was realized in chestnut plants. Various parameters related to soil fertility, and plant growth, nutrition, and physiology were investigated to gain knowledge towards more sustainable management. After ZEO application and in comparison to CRF, an impressive boost in soil K was achieved. Moreover, soil P and Zn levels were higher in the VER-treated soil, compared to CRF. Leaf K and Ca concentrations were significantly higher in ZEO, compared to the VER treatment; the highest foliar N and Zn concentrations were measured in CRF and VER, respectively. However, significantly lower foliar Mn and Cu were found in VER. The highest root biomass produced in the ZEO treated plants. For most nutrients, their total uptake per plant was higher in CRF and ZEO. Finally, photosynthetic rates were higher in VER (mainly due to non-stomatal factors) and CRF (mainly due to stomatal factors). Our data open a discussion towards the application of ZEO and/or VER as soil amendments in chestnut nurseries and orchards, aiming at partially decreasing fertilization rates and boosting sustainable nutrient management.

More is not always better-lower estradiol to mature oocyte ratio improved IVF outcomes.

AimTo find a cut-off ratio of estradiol/metaphase II oocyte (E2/M2) ratio and to evaluate the correlation with patients’ characteristics, embryo morphokinetics using EmbryoScope™ and IVF cycle outcomes.Material and methodsFor this retrospective cohort study, records of all fresh cycles that were cultured and scored by EmbryoScope™ were evaluated. The peak E2/M2 ratio was calculated on the day of human chorionic gonadotropin (hCG) administration and correlated to embryo morphokinetic quality and cycle outcomes. A receiver operating characteristics analysis was calculated for the E2/M2 ratio and clinical pregnancy rates.ResultsA total of 2461 oocytes were collected from 319 patients. Receiver operating characteristics analysis revealed a cutoff of 204 as a discriminative point to predict clinical pregnancy with a sensitivity of 69.5% and specificity of 62.1% (P < 0.001). E2/M2 > 204 group were older, had higher E2 concentration, fewer M2 oocytes despite elevated gonadotrophin doses. E2/M2 ratio ≤ 204 was correlated with higher fertilization rate, better embryo quality, higher pregnancy and live birth rates, and more frozen embryos.ConclusionE2/M2 ratio < 204 yielded the best probability to achieve good quality embryos with good morphokinetic scores and better pregnancy outcomes and may be used to predict IVF cycle outcomes. Advanced maternal age and low ovarian response received higher concentrations of gonadotrophins, which resulted in higher E2/M2 ratio. Milder stimulation to those patients may improve their cycle outcomes.

Birth of a healthy child fathered by a man with Klinefelter`s syndrome after preimplantation genetic testing

Introduction. Most men with non-mosaic Klinefelter?s syndrome (KS; 47, XXY) have azoospermia, and were until recently considered completely infertile. However, it has been confirmed that some non-mosaic patients had spermatozoa in the ejaculate, although severe oliogasthenoterato-soospermia was present in all of them. Although a high fertilization rate with an intracytoplasmic sperm injection (IC-SI) procedure using sperm from a non-mosaic patient and the cumulative pregnancy rate following in vitro fertilization constitute 53%, the incidence of live births after ICSI using sperm of men with non-mosaic KS is very low: 1 in 8 cases. Case report. At the Clinical Centre of Vojvodina?s Department of Gynecology and Obstetrics, a successful in vitro fertilization treatment was conducted using the sperm of a man with KS non-mosaic syndrome. Preimplantation genetic testing was performed for the embryo selection, and an euploid embryo was transferred in the subsequent natural cycle. Delivery of male newborn was spontaneous, vaginal, with head presentation, after 40 weeks and 3 days. The newborn?s Apgar score was 10/10. His birth weight was 3,950 g, and his length was 55 cm. At 12 months of age, his psychomotor development was assessed as normal on the Brunet-L?zine psychomotor development scale. Conclusion. Due to an increased risk of chromosomal abnormalities (abnormalities of sex or autosomal chromosomes) in embryos from couples with KS males, preimplantation genetic testing is conducted to select a chromosomally normal embryo. This may help achieve pregnancy sooner, decrease the chance of multiple pregnancy and its potential complications, decrease the risk of miscarriage, and reduce the need for invasive prenatal diagnostic procedures and the risks of other complications, as well as the risk of late termination of pregnancy in case of pathological findings of the fetal karyo-type using conventional diagnostic procedures.

12 Artificial insemination and embryo transfer results in ewes during a long daylength period

Sheep are polyestrous, short-day breeders (∼11h of daylength), and exhibit oestrus approximately every 16–17 days during the breeding season, usually in late September to late December in the Northern Hemisphere. Progressive sheep producers often use assisted reproductive techniques such as laparoscopic AI and ovarian hyper-stimulation, embryo collection, and embryo transfer (ET) to increase genetic gain, and strive to have early December lambs to target specific show markets, which dictates AI or ET during the late summer. This field trial compared pregnancy rates following AI or ET in July and August (∼14h of daylength) in southwest Virginia (36–38′12″ N). Ewes (AI, n=83; ET recipients, n=33) were synchronized using a modified Ovsynch protocol involving intravaginal progesterone implants for 14 days, prostaglandin F2α (intramuscular) 48h before expected oestrus, and PG600 (IM) and gonadotrophin-releasing hormone (intramuscular) 52 to 54h and 16h before AI, respectively. Ewes were subjected to AI (frozen/thawed semen) regardless of whether they displayed signs of oestrus, and ewes selected as embryo recipients were subjected to a similar protocol but instead received 1 or 2 embryos (based upon the number of viable embryos produced per embryo donor) 6 days following the AI of the embryo donors. Ovarian hyper-stimulation of the embryo donors (n=13) was enabled by twice-daily FSH injections [totalling 350–455IU of Folltropin V (10–13mL)] for the 4 days before AI. Six days following AI, embryos were recovered surgically from the embryo donors (n=13) and yielded an average (±s.e.m.) of 6.6±1.2 total ova, 4.7±1.1 transferable quality embryos, and 1.9±0.8 unfertilized ova per collection. Pregnancy was detected using transrectal ultrasonography at ∼30 days of gestation and the pregnancy rates were analysed using Chi-squared. There was a tendency (P=0.092) for more pregnancies to be established following ET (22/33; 66%) compared with AI (41/83; 49%). There was no statistical relationship between AI ewes or ET recipient ewes that became pregnant relative to whether they displayed signs of oestrus or not. Embryo transfer was a more successful approach to produce pregnancies in ewes compared with AI during long daylength periods in this field trial. Further, ova from hyper-stimulated embryo donor ewes experienced a very high fertilization rate. Future studies will evaluate the ova capability directly via laparoscopic aspiration of ovarian follicles and IVF and evaluation of hyper- and non-hyper-stimulated follicular waves (using transrectal ultrasonography) and endocrine dynamics during different long and short daylength periods. Extending the opportunity to generate embryos and offspring regardless of daylength will assist aggressive sheep producers in reaching their reproductive, financial, and genetic goals.

Dual trigger improves response to ovarian stimulation and ICSI outcomes in patients with a previous r-hCG triggered ICSI cycle.

ObjectiveTo evaluate if ovarian response to controlled ovarian stimulation (COS) and intracytoplasmic sperm injection (ICSI) outcomes are improved by the use of dual trigger (gonadotropin-releasing hormone (GnRH) agonists plus recombinant human chorionic gonadotropin (r-hCG)) in patients with previous cycles triggered with r-hCG.MethodsThis case-control study included 88 matched cycles performed in 88 patients, which had the first ICSI cycle triggered with r-hCG (n=44), and the following ICSI cycle with dual trigger (n=44). We compared the cycle outcomes between the groups. In a second case-control within-subject analyses, we compared the ICSI outcomes between patients which had the first ICSI cycle triggered with r-hCG only (n=18), and the following ICSI cycle with dual trigger (n=18) or r-hCG only (n=18).ResultsUpon investigating repeated cycles (r-hCG only vs. dual trigger), we found higher oocyte yield and mature oocyte rates, lower immature oocyte rates, higher fertilization rates, and higher blastocyst development rates; and higher rates of cycles with embryos transferred and implantation in the dual trigger cycle.ConclusionsThe dual trigger regimen is a more effective approach than r-hCG trigger in patients with a previous r-hCG triggered ICSI cycle, yielding improved response to COS, and better laboratorial and clinical outcomes.

Amphibian reproductive technologies: approaches and welfare considerations.

Captive breeding and reintroduction programs have been established for several threatened amphibian species globally, but with varied success. This reflects our relatively poor understanding of the hormonal control of amphibian reproduction and the stimuli required to initiate and complete reproductive events. While the amphibian hypothalamo-pituitary-gonadal (HPG) axis shares fundamental similarities with both teleosts and tetrapods, there are more species differences than previously assumed. As a result, many amphibian captive breeding programs fail to reliably initiate breeding behaviour, achieve high rates of fertilization or generate large numbers of healthy, genetically diverse offspring. Reproductive technologies have the potential to overcome these challenges but should be used in concert with traditional methods that manipulate environmental conditions (including temperature, nutrition and social environment). Species-dependent methods for handling, restraint and hormone administration (including route and frequency) are discussed to ensure optimal welfare of captive breeding stock. We summarize advances in hormone therapies and discuss two case studies that illustrate some of the challenges and successes with amphibian reproductive technologies: the mountain yellow-legged frog (Rana muscosa; USA) and the northern corroboree frog (Pseudophryne pengilleyi; Australia). Further research is required to develop hormone therapies for a greater number of species to boost global conservation efforts.

Microbial Properties of a Ferric Lixisol as Affected by Long Term Crop Management and Fertilization Regimes in Burkina Faso, West Africa

We used an ongoing long-term field trial established since 1960 in Burkina Faso, to study the microbial properties of a Ferric Lixisol under various crop management and fertilization regimes. Microbial respiration rate, microbial biomass carbon (MBC) and soil bacteria’s number were assessed in soil samples taken at 0 - 20 cm depth. The crop management were continuous cropping of sorghum (Sorghum bicolor L.) (S/S) and rotation between sorghum and cowpea (Vigna unguiculata L.) (S/C), while the fertilization regimes were: 1) Control (te); 2) Low rate of mineral fertilizer (fm); 3) Low rate of mineral fertilizer + sorghum straw restitution (fmr); 4) Low rate of mineral fertilizer + low rate of manure (fmo); 5) High rate of mineral fertilizer (FM); and vii) High rate of mineral fertilizer + high rate of manure (FMO). The manure is applied every second year. The results indicate that sorghum/cowpea rotation significantly increase MBC and bacteria number as compared to continuous sorghum cropping. MBC ranged from 335.5 to 54.85 μg C g−1 soil with S/S and from 457.5 to 86.6 μg C g−1 soil with S/C. Application of high level of manure and mineral fertilizer increase microbial respiration rate and MBC. The highest MBC was observed with FMO and the lowest with the control. In general, the metabolic quotient (qCO2) was negatively impacted by the fertilization and cowpea rotation. For S/S rotation, qCO2 of the control was 1.5 to 2 times that of the treatments with low mineral fertilizer (fmr, fmo and fm) and 3 times that of the high rate of fertilization (FM and FMO). With S/C rotation, qCO2 of the control was 2 times of that fmr, FM and FMO and 0.8 times that of fmo and fm. Soil bacteria in the fmr were 63.6 and 12.4 times the control in the S/S and S/C rotations, respectively. In sum, combined application of manure and mineral fertilizer with crop rotation is the best management practices to improve in sustainable way microbial activities in tropical soil.

79 Progesterone-induced acrosome reaction and fertilization rates with bovine intracytoplasmic sperm injection

Intracytoplasmic sperm injection (ICSI) has been a valuable tool in many species because of its ability to overcome male factor infertility problems and eliminate risk of polyspermy; more recently, it been used to improve genome editing technologies. However, limited success with bovine ICSI has hindered these applications in cattle. Numerous treatments have been used to increase the success rate, with marginal improvement. Replicating events synonymous with fertilization, such as the acrosome reaction, may improve fertilization with bovine ICSI. Progesterone (P4) is naturally found in both the cumulus cells surrounding the oocyte and follicular fluid released at ovulation and activates a physiological pathway within sperm to induce an acrosome reaction, a crucial process in fertilization. Progesterone induction of the acrosome reaction as a sperm pretreatment for ICSI has not yet been evaluated in cattle. In this study, frozen–thawed bovine sperm was used. Sperm were first thawed, washed, and separated via gradient to obtain the motile population before capacitation with heparin over 4h before treatment with or without P4 (10 μM) for 15min. To measure the acrosome reacting population, sperm were stained with fluorescein isothiocyanate-conjugated peanut agglutinin (FITC-PNA) and observed over 2h using cytometric flow analysis and fluorescent microscopy to measure the population undergoing and completing an acrosome reaction. For ICSI, a total of 220 oocytes were used, and both treated and nontreated sperm were incubated for 1h before injection to allow for completion of an acrosome reaction. Fertilization rates were measured by observing pronuclear formation and an absence of sperm 18h after ICSI. Means of acrosome reacting population gathered by flow cytometry and microscopy were analysed by ANOVA. Differences in fertilization rates between groups post ICSI were analysed using a Yates’ corrected chi-squared test. A significantly higher proportion of P4 treated versus control sperm initiated an acrosome reaction at hour 1 (80.2%±4.2 vs. 19%±9.1), which increased to (89.3%±3.9 vs. 29%±8.3) after 2h. P4 also increased the percentage of sperm that completed an acrosome reaction, from 50% (±5.1) at hour 1 and 62.5% (±7.4) at hour 2. Only 14.2% (±3.6) completed acrosome reactions in sperm not treated with P4 by hour 2. Motile sperm in both groups did not decrease over the 2-h incubation time period (P&amp;lt;0.05). Progesterone treatment increased the percentage of fertilized embryos after ICSI, with 38.1% fertilized compared with 10.1% with heparin-treated control injections (P&amp;lt;0.001). These results show that P4 has effects on bovine sperm that allow for higher rates of fertilization after ICSI by utilising the sperm’s physiological response to progesterone. Further embryo development using ICSI with P4-treated sperm, or additional physiologically similar treatments, should continue to be assessed.

Spring camelina: Effect of mineral fertilization on the energy efficiency of biomass production

The aim of this study was to determine the effect of nitrogen (0, 40, 80, 120, 160 kg ha−1) and sulfur (0, 15, 30 kg ha−1) fertilization on the energy efficiency ratio of spring camelina produced in north-eastern Poland. The energy inputs in the production of camelina ranged from 5.1 (without nitrogen and sulfur fertilization) to 17.7 GJ ha−1 (160 kg N ha−1 and 30 kg S ha−1). The energy output of camelina produced without nitrogen or sulfur fertilizers was determined at 28.38 (seeds) and 61.53 GJ ha−1 (seeds and straw). High rates of nitrogen and sulfur fertilization increased the energy output of camelina seeds and biomass by up to 186% and 155%, respectively. Nitrogen fertilizer applied at 120 kg ha−1 decreased the energy efficiency ratio by 49% in seeds and by 55% in total biomass. The application of sulfur increased the energy efficiency ratio of seeds by 1–8%, and the energy efficiency ratio of total biomass by 1–5%. Sulfur enhanced the energy efficiency ratio of camelina in production technologies with high rates of nitrogen fertilization.

Optimization of water and fertilizer management improves yield, water, nitrogen, phosphorus and potassium uptake and use efficiency of cotton under drip fertigation

As a fiber crop and oil crop, cotton plays an important role in the economic development of northwest China, but the lack of appropriate field water and fertilizer management strategies has restricted the harmonious development of cotton industry and environment. Field experiments were implemented to explore the coupling effects of various drip irrigation and fertilizer levels on the dry matter, yield, water and fertilizer use efficiency of cotton. The three drip irrigation levels included 1.0 ETC (full irrigation), 0.8 ETC (20% deficit) and 0.6 ETC (40% deficit), where ETC is the crop evapotranspiration. The five fertilizer (N-P-K) levels were F1 (150–26.2–24.9 kg ha−1), F2 (200–34.9–33.2 kg ha−1), F3 (250–43.7–41.5 kg ha−1), F4 (300–52.4–49.8 kg ha−1) and F5 (350–61.1–58.1 kg ha−1). The results revealed that the seed cotton yield and lint yield showed increasing trends as the irrigation water amount increased at the same fertilizer level during 2012–2014. When full irrigation (1.0 ETC) was applied, the dry matter accumulation, seed cotton yield, N, P and K accumulation in plants and water productivity were the highest under F4 (300–52.4–49.8 kg ha−1) in 2012 and 2014. However, the lint yield was highest in 2012 and 2013 under F3 (250–43.7–41.5 kg ha−1). At the same irrigation level, N, P and K use efficiencies were higher at low fertilization rates than those at high fertilization rates in 2012 and 2013. Deficit irrigation and fertilization levels led to a severe decrease in cotton yield. N, P and K use efficiencies were low under F4. Comprehensively considering cotton yield, N, P and K uptake and use efficiency, the application of irrigation amount of 1.0 ETC and N-P-K rate of 250–43.7–41.5 kg ha−1 was the best drip fertigation strategy for cotton production in arid regions of northwest China.

Melatonin levels and microRNA (miRNA) relative expression profile in the follicular ambient microenvironment in patients undergoing in vitro fertilization process.

Intrafollicular fluid (IFF) melatonin plays a decisive role in maintaining granulosa cells' DNA integrity and protects them against apoptosis. It reduces oxidative stress and improves the oocyte quality with a higher fertilization rate. This prospective study investigated the antioxidant property of IFF melatonin and its impact on IVF outcome parameters. We also explored the relative expression of five microRNAs (miR-663b, miR-320a, miR-766-3p, miR-132-3p, miR-16-5p) and levels of cell-free DNA (cfDNA) by real-time PCR in unexplained infertile patients. We collected 425 follicular fluid (FF) samples containing mature oocytes from 295 patients undergoing IVF. Patients were subgrouped based on IFF melatonin concentration (group A ≤ 30pg/mL, group B > 70 to ≤ 110pg/mL, group C > 111 to ≤ 385pg/mL). Our results showed that patients with ≤ 30pg/mL IFF melatonin levels have significantly higher oxidative stress markers, cfDNA levels, and lower relative expression of miR-663b, miR-320a, miR-766-3p, miR-132-3p, and miR-16-5p compared to other subgroups (p < 0.001). Similarly, they have a low fertilization rate and a reduced number of high-quality day 3 embryos. Findings suggest that the therapeutic use of melatonin produces a considerable rise in the number of mature oocytes retrieved, fertilization rate, and good-quality embryo selection. Furthermore, miRNA signature enhances the quality of embryo selection, thus, may allow us to classify them as non-invasive biomarkers to identify good-quality embryos.

Sources, Influencing Factors, and Pollution Process of Inorganic Nitrogen in Shallow Groundwater of a Typical Agricultural Area in Northeast China

As one of the largest agricultural areas, the Sanjiang Plain of Northeast China has faced serious inorganic nitrogen pollution of groundwater, but the sources and the formation mechanism of pollution in the regional shallow groundwater remain unclear, which constrains the progress of pollution control and agricultural development planning. An investigation on potential nitrogen sources, groundwater inorganic nitrogen compounds (NH4+, NO3−, NO2−), and topsoil total nitrogen concentration (TN) was conducted in a typical paddy irrigation area of Sanjiang Plain. Multivariate statistical analysis combined with geospatial-based assessment was applied to identify the sources, determine the governing influencing factors, and analyze the formation process of inorganic nitrogen compounds in shallow groundwater. The results show that the land use type, oxidation-reduction potential (Eh), groundwater depth, NO2− concentration, and electrical conductivity (EC) are highly correlated with the NO3− pollution in groundwater, while DO and Eh affected the distribution of NH4+ most; the high concentrations of NO3− in sampling wells are most likely to be found in the residential land and are distributed mainly in densely populated areas, whereas the NH4+ compounds are most likely to accumulate in the paddy field or the lands surrounded by paddy field and reach the highest level in the northwest of the area, where the fields were cultivated intensively with higher fertilization rates and highest values of topsoil TN. From the results, it can be concluded that that the NO3− compounds in groundwater originated from manure and domestic waste and accumulated in the oxidizing environment, while the NH4+ compounds were derived from N fertilization and remained steady in the reducing environment. NO2− compounds in groundwater were the immediate products of nitrification as a result of microorganism activities.

Plot-Scale Agroforestry Modeling Explores Tree Pruning and Fertilizer Interactions for Maize Production in a Faidherbia Parkland

Poor agricultural productivity has led to food shortages for smallholder farmers in Ethiopia. Agroforestry may improve food security by increasing soil fertility, crop production, and livelihoods. Agroforestry simulation models can be useful for predicting the effects of tree management on crop growth when designing modifications to these systems. The Agricultural Production Systems sIMulator (APSIM) agroforestry tree-proxy model was used to simulate the response of maize yield to N fertilizer applications and tree pruning practices in the parkland agroforestry system in the Central Rift Valley, Ethiopia. The model was parameterized and tested using data collected from an experiment conducted under trees and in crop-only plots during the 2015 and 2016 growing seasons. The treatments contained three levels of tree pruning (100% pruned, 50% pruned, and unpruned) as the main plots, and N fertilizers were applied to maize at two rates (9 or 78 kg N ha−1) as sub-plots. Maize yield predictions across two years in response to tree pruning and N applications under tree canopies were satisfactorily simulated (NSE = 0.72, RSR = 0.51, R2 = 0.8). Virtual experiments for different rates of N, pruning levels, sowing dates, and cultivars suggest that maize yield could be improved by applying fertilizers (particularly on crop-only plots) and by at least 50% pruning of trees. Optimal maize yield can be obtained at a higher rate of fertilization under trees than away from them due to better water relations, and there is scope for improving the sowing date and cultivar. Across a 34-year range of recent climate, small increases in yields due to optimum N-fertilizing and pruning were probably limited by nutrient limitations other than N, but the highest yields were consistently in the 2–4 m zone under trees. These virtual experiments helped to form hypotheses regarding fertilizers, pruning, and the effects of trees on soil that warrant further field evaluation.

The Contribution of Chemical, Organic and Bio-Fertilizers on Rice Production in Iran: A Meta-analysis

Rice (Oryza sativa L.) is an important global food crop and a main source of calories for about 60% of the world population. Fertilizers are essential components of modern agriculture and play a vital role in improving rice and other crops yield. We performed a meta-analysis to determine how different types of fertilizers including chemical (nitrogen (N), phosphorus (P), 18 potassium (K), silicon (Si), and micronutrients), organic (compost and manure) and bio-fertilizers (plant growth promoting rhizobacteria (PGPR) and fungi (PGPF)) influence on rice productivity in Iran. A significantly positive overall effect of fertilizers was noted on biological yield (28.39%), grain yield (26.02%), harvest index (3.17%) and 1000-grain weight (4.86%). Chemical, organic and bio-fertilizers positively influenced grain yield by 26.78, 15.20 and 26.61%, respectively. Among all types of fertilizers, N has the most important role in rice production and responsible for 38% of yield. For N and P, the most increase of yield (47.60 and 20.52%, respectively) had been calculated in high fertilization rates (>120 and >80 kg h–1, respectively), while the highest rice yield was obtained from moderate K and Si fertilization rates (40–80 and 250–500 kg ha–1, respectively). Therefore, it seems that lower rates of K and Si fertilizers could be used in paddy fields for reaching optimum yield. Overall, this meta-analysis indicated that about 27, 15, and 27% of rice yield is attributable to chemical, organic and bio-fertilizers, respectively.