Recovery Of Fertilizer Research Articles

Возможности сохранения и восстановления фертильности после хирургического лечения трубной беременности

The efficacy of measures that improved postoperative rehabilitation of natural fertility in women after conservative surgical treatment of progressive tubal pregnancy (TP) was assessed. A randomized, controlled, open examination of 102 those who planned pregnancy, have undergone treatment endovideosurgical progressive TP was held. The improved complex of rehabilitation: 1) used anti-adhesive barrier; 2) bacteriological and virological examination of discharge from the fallopian tubes, followed by determination of sensitivity to antibiotics; 3) for the rehabilitation of the reproductive system, improve the regenerative processes in the fallopian tubes, and effective contraception for women of the main group in the postoperative period were appointed individually combined oral contraceptives (drospirenone 3 mg/ethinylestradiol 30 mcg) the duration of 9-12 months; 4) anti-inflammatory therapy (nonsteroidal anti-inflammatory drugs in the form of rectal suppositories, enzyme) was determined. The effectiveness of the improved complex to recovery of fertility in women after conservative surgical treatment of progressive TP was 80%.

Influence of enhanced efficiency fertilisation techniques on nitrous oxide emissions and productivity response from urea in a temperate Australian ryegrass pasture

The effect of a nitrification inhibitor on nitrous oxide (N2O) emissions across seasons, the effect of a urease inhibitor and a fine particle spray (both targeting ammonia (NH3) loss) on N2O emissions, and the potential for productivity benefits and efficiencies by using these enhanced efficiency fertilisers (EEFs) were investigated in temperate pastures. The study compared three treatments over an eight month period (April to December 2010): (1) urea (U), (2) urea with a nitrification inhibitor (3,4-dimethylpyrazole phosphate) (DMPP), and (3) urea with a urease inhibitor (N-(n-butyl) thiophosphoric triamide (NBTPT)) (GU). In autumn, when NH3 loss was predicted to be high, the effect of urea applied as a fine particle spray (containing urea, NBTPT and gibberellic acid (10g ha–1)) (FPA) on N2O emissions and productivity was determined. N2O emissions from urea applied to pastures were low, and were larger in spring than autumn due to soil moisture and temperature. DMPP was an effective tool for mitigating N2O emissions, decreasing fertiliser-induced N2O emissions relative to urea by 76% over eight months. However, the urease inhibitor (NBTPT) (GU) increased N2O emissions from urea by 153% over eight months. FPA had no impact on N2O, but was only examined during periods of low emission (autumn). No significant biomass productivity, agronomic efficiency benefits, or improvements in apparent fertiliser recovery were observed with the DMPP and GU treatments. A significant biomass productivity benefit was observed with the FPA treatment 55 days after fertiliser was applied, most likely because of the gibberellic acid. The outcomes highlight that although DMPP effectively decreased N2O emissions it had no impact on biomass productivity compared with urea. The use of the GU increased N2O emissions by preserving NH3 in the soil. To avoid this a lower rate of N should be applied with the urease inhibitor.

Struvite: a slow-release fertiliser for sustainable phosphorus management?

Background and aimRecycled sources of phosphorus (P), such as struvite extracted from wastewater, have potential to substitute for more soluble manufactured fertilisers and help reduce the long-term threat to food security from dwindling finite reserves of phosphate rock (PR). This study aimed to determine whether struvite could be a component of a sustainable P fertiliser management strategy for arable crops.MethodsA combination of laboratory experiments, pot trials and mathematical modelling of the root system examined the P release properties of commercial fertiliser-grade struvite and patterns of P uptake from a low-P sandy soil by two different crop types, in comparison to more soluble inorganic P fertilisers (di-ammonium phosphate (DAP) and triple super phosphate (TSP)).ResultsStruvite had greatly enhanced solubility in the presence of organic acid anions; buckwheat, which exudes a high level of organic acids, was more effective at mobilising struvite P than the low level exuder, spring wheat. Struvite granules placed with the seed did not provide the same rate of P supply as placed DAP granules for early growth of spring wheat, but gave equivalent rates of P uptake, yield and apparent fertiliser recovery at harvest, even though only 26 % of struvite granules completely dissolved. Fertiliser mixes containing struvite and DAP applied to spring wheat have potential to provide both optimal early and late season P uptake and improve overall P use efficiency.ConclusionsWe conclude that the potential resource savings and potential efficiency benefits of utilising a recycled slow release fertiliser like struvite offers a more sustainable alternative to only using conventional, high solubility, PR-based fertilisers.Electronic supplementary materialThe online version of this article (doi:10.1007/s11104-015-2747-3) contains supplementary material, which is available to authorized users.

Fertility Recovery Following Allogeneic Bone Marrow Transplantation in Aplastic Anemia; A Study of 157 Patients

Introduction:Infertility is a major late effect of hematopoietic stem cell transplants (HSCT). In aplastic anemia (AA) patients, although the fertility recovery rate is relatively higher than other diseases but the exact incidence and risk factors are not very well studied. In this study, we attempted to evaluate incidence and the impact of patientÕs characteristics and transplantation procedures on fertility recovery following allogeneic HSCT for adolescent and adults patients with AA.Methods:A total of 157 patients who were at least 14 years old with AA receiving HSCT between year 1987 and 2014 at our center were reviewed. Patients who survived at least 2 years following HSCT and either married or in relationship were included in the analysis and evaluated for fertility following HSCT. 87 patients were eligible for the study. Questionnaire survey and long-term charts were used for data collection. With a response rate and or available information of 63% patients, 55 patients were identified and stratified into fertility recovery (FR+) versus non-fertility recovery (FR-) group. Fertility recovery was defined by a pregnancy of the patient or his partner.Results:Median age for all patients is 23 years (range, 14 -50), 44% (n=24) between 14-20 years old, 51% (n=28) between age 20-40 years and 5% (n=3) > 40 years. 51% (n=28) were females. Matched related donor was used for majority of patients 96% (n=53). GVHD prophylaxis was CSA/MTX for 93% (n=51,). Conditioning regimen was Cyclophosphamide/Flu in 25 (45%), Cyclophosphamide /ATG in 18 patients (35%) and others in 12 patients (20%). Bone marrow was the source of stem cells for 52 patients (94%).A median follow-up of 8 years for survivors (range, 0.3 -23) showed 45 patients (82%) had FR+ while 10 patients (18%) were FR-. Median duration of fertility recovery (from delivery to BMT) was 6 years (range, 0.8-19) with significant difference based on age groups, 4 years for patients 20-40 years (n=29, 53%) versus 8 years for those < 20 years (n=24, 44%), (p=0.002), (Figure 1). None of the patients >40 years old (n=2, 4%) had fertility recovery.Comparison based on gender showed no significant difference. Males had a median duration of fertility recovery of 5.9 years, (range 0.6-14.9) versus 6.2 years, (range, 0.8-15.2) (p=0.31) females. The overall median number of pregnancies was 2 (range, 1-6). For males, it was 2 (range, 1-6) while 1.5 (range, 1-5) for females (p=0.26). Deliveries occurred in natural ways in (95%) while C-section for (5%). All deliveries were without fetal abnormalities.Univariate analysis of risk factors for fertility recovery showed age group (p=0.03) and chronic GVHD (p=0.05) are important factors. Neither gender of patients or type of preparative regimens used for HSCT (Cyclo/ATG vs Cyclo/Flu) was a risk factor. In multivariate analysis, age group was the only confirmed an independent risk factor for fertility recovery (p=0.02) [HR= 2.02, CI=1.012-3.64).Conclusion:The present study suggested that the incidence of fertility recovery following HSCT for patients with aplastic anemia is high with no significant differences between males and females. Patients between the ages of 20-40 years at the time of HSCT have significantly shorter recovery period. Age was the only independent risk factor for fertility recovery while there was no impact of whether ATG or Fludarabine was used in addition to Cyclophosphamide as preparative regimen. [Display omitted] DisclosuresKim:Bristol-Myers Squibb: Consultancy, Research Funding; Novartis Pharmaceuticals: Consultancy, Research Funding.

Residual recovery and yield performance of nitrogen fertilizer applied at sugarcane planting

The low effectiveness of nitrogen fertilizer (N) is a substantial concern that threatens global sugarcane production. The aim of the research reported in this paper was to assess the residual effect of N-fertilizer applied at sugarcane planting over four crop seasons in relation to sugarcane crop yield. Toward this end three field experiments were established in the state of Sao Paulo, Brazil, during February of 2005 and July of 2009, in a randomized block design with four treatments: 0, 40, 80 and 120 kg ha−1 of N applied as urea during sugarcane planting. Within each plot, a microplot was established to which 15N-labeled urea was applied. The application of N at planting increased plant cane yield in two of the three sites and sucrose content at the other, whereas the only residual effect was higher sucrose content in one of the following ratoons. The combined effect was an increase in sugar yield for three of the 11 crop seasons evaluated. Over the crop cycle of a plant cane and three ratoon crops, only 35 % of the applied N was recovered, split 75, 13, 7 and 5 % in the plant cane, first, second and third ratoons, respectively. These findings document the low efficiency of N recovery by sugarcane, which increases the risk that excessive N fertilization will reduce profitability and have an adverse effect on the environment.

VSELs may obviate cryobanking of gonadal tissue in cancer patients for fertility preservation.

BackgroundInfertility is an undesirable side effect and gonadal tissue banking is advocated in young cancer patients who are unable to preserve embryos or gametes prior to oncotherapy to achieve biological parenthood later on. Banking gonadal tissue is challenging and protocols to mature gametes in vitro are not yet clinically established. Transplanting ovarian cortical tissue at hetero-or orthotopic sites in women and bone marrow transplantation (BMT) in both men and women has resulted in spontaneous recovery of fertility, pregnancy and live births. Various studies in humans and mice suggest that genetic origin of offspring after BMT is similar to transplanted patient and not the donor. Thus the source of oocytes/sperm which result in spontaneous pregnancies still remains contentious.FindingsVery small embryonic-like stem cells (VSELs) have been reported in adult human testis and ovary, in azoospermic testicular biopsies from survivors of childhood cancer and also in women with premature ovarian failure and menopause. VSELs survive chemotherapy because of their quiescent nature and can be detected in chemoablated mice gonads at protein and mRNA level and also by flow cytometry. Surviving VSELs spontaneously differentiate into oocyte-like structures and sperm when inhibitory factors are overcome in vitro. Transplantation of mesenchymal cells (isolated from different sources) has led to regeneration of chemoablated mouse gonads and also live births. Spermatogenesis is also restored from endogenous stem cells on inter-tubular transplantation of Sertoli cells in chemoablated mouse testis.ConclusionsEndogenous VSELs (which survive oncotherapy) can possibly regenerate non-functional gonads in cancer survivors when exposed to a healthy niche in vitro or in vivo (by way of transplanting mesenchymal cells which secrete trophic factors required for endogenous VSELs to differentiate into gametes). Presence of VSELs can also explain spontaneous pregnancies after BMT and cortical tissue transplantation (at heterotopic or orthotopic sites). This understanding once verified and accepted by the scientific community could obviate the need to remove whole ovary or testicular biopsy for cryopreservation prior to oncotherapy.

Annual nitrogen dynamics and urea fertilizer recoveries from a dairy pasture using 15N; effect of nitrification inhibitor DMPP and reduced application rates

Direct nitrogen (N) losses from pastures contribute to the poor nitrogen use efficiency of the dairy industry, though the exact fate of applied N and the processes involved are largely unknown. Nitrification inhibitors such as DMPP can potentially increase fertilizer N use efficiency (NUE), though few studies globally have examined the effectiveness of DMPP coated urea in pastures. This study quantified the NUE of DMPP combined with reduced application rates, and the effect on N dynamics and plant–soil interactions over an annual ryegrass/kikuyu rotation in Queensland, Australia.Labeled 15N urea and DMPP was applied over 7 winter applications at standard farmer (45kgNha−1) and half (23kgNha−1) rates. Fertilizer recoveries and NUE were calculated over 13 harvests, and the contribution of fertilizer and soil N estimated. Up to 85% of the annual N harvested was from soil organic matter. DMPP at the lower rate increased annual yields by 31% compared to the equivalent urea treatment with no difference to the high N rates. Almost 40% of the N added at the conventional fertilizer application rate as urea was lost to the environment; 80kgNha−1 higher than the low DMPP. Combining the nitrification inhibitor DMPP with reduced fertilizer application rates shows substantial potential to reduce N losses to the environment while sustaining productivity in subtropical dairy pastures.

The fate of urea nitrogen applied to a vegetable crop rotation system

To investigate the fate of urea nitrogen (N) applied to vegetable fields, three N rates, N0 (0 kg N/ha), N1(225 or 240 kg N/ha) and N2 (450 or 480 kg N/ha) were applied to a rotation system. Nitrogen fertilizer recovery (NFR), N residue in soil, and N losses were measured in situ. Higher N application rates resulted in lower NFR, and increased N residues in soil and losses. The NFR, Chinese cabbage, and eggplant were different in the N1 and N2 groups (P < 0.01). The ratios of N fertilizer residue at 0–60 cm deep ranged from 30.2 to 41.1 % (N1), and 33.1 to 57.7 % (N2). The N loss ratios were only 6.6 % (N1) and 11.9 % (N2), because of the lower precipitation rates and temperatures characteristic of its growing season; meanwhile, N losses were 31.1 and 37.4 % in cayenne pepper, and 24.1 and 29.2 % in eggplants in the N1 and N2 treatments, respectively. The main pathways of N loss were leaching, followed by gaseous losses; these were major pathways of N loss in seasons with lower precipitation rates. NH3 volatilization was correlated with soil temperature (P < 0.01), and N2O emissions were correlated with soil moisture in the N1 treatment and with soil NH4 +-N concentration in the N2 treatment (P < 0.01). Denitrification rates were correlated with soil moisture in the N0 and N1 treatments, and with NO3 −-N content in the N2 treatment (P < 0.01). Finally, loss due to runoff was correlated with precipitation (P < 0.01).

Novel Drug Therapies for Fertility Preservation in Men Undergoing Chemotherapy: Clinical Relevance of Protector Agents.

Cancer has been affecting a growing number of children, adolescents and adult males in reproductive age. Male reproductive potential is adversely affected by chemotherapeutic drugs and patients are at risk for prolonged infertility. Fertility recovery is related to the chemotherapeutic agent and dosage used, being thus difficult to predict. As a result, there is a strong need to identify a natural or synthetic compound that is able to preserve male fertility without interfering with the efficacy of the chemotherapeutic regimen. New procedures, as well as several drugs, are being investigated to assess their efficiency in protecting male reproductive functions from the chemotherapy side-effects. This review provides an overview of the wide range of chemotherapeutic drugs regularly used in cancer treatment and their detrimental effects on male fertility. In addition, it also assesses the existing protector agents for male fertility and their usefulness in preserving and protecting male reproductive functions exposed to chemotherapeutics. Several protector agents for male fertility are being studied, and results are promising. Nonetheless, further research must be implemented to identify a supplemental therapy that addresses the multiple side effects of chemotherapy on male reproductive function. Until such therapy is discovered, it is fundamental that all fertility preservation options are discussed with patients, before treatment is initiated, to assure parenthood.

Recovery of 15N-labeled Fertilizer by Thompson Seedless Grapevines: Effects of N Fertilizer Type and Irrigation Method

A study was conducted to determine the N fertilizer recovery efficiency (RE_N) of <i>Vitis vinifera</i> L. cv. Thompson Seedless grown in the San Joaquin Valley of California. Vines were drip- or furrow-irrigated and fertilized with ¹⁵N-labeled potassium nitrate (KNO₃) or ammonium sulfate (NH₄)₂SO₄. The fertilizers were applied shortly after anthesis with a single application of 25 g N/vine (~28 kg N/ha). An additional set of the drip-irrigated vines was fertilized 10 times beginning 20 April across a 20-week period during the growing season with labeled KNO₃ (amounts equivalent to ~31 kg N/ha). Total biomass, N concentrations, and ¹⁵N of all vine organs, including the root system, were measured. There were no significant differences in RE_N (~40%) between the two fertilizer types (nitrate versus ammonium) for the drip-irrigated vines or for the comparison of a single application of KNO₃ to a split application of that fertilizer applied every two weeks. The RE_N of furrow-irrigated vines was ~12%. The partitioning of ¹⁵N-labeled fertilizer taken up by the vine was significantly affected by fertilizer treatment. Approximately 47% of the ammonium fertilizer for the drip-irrigated vines was found in the clusters, while only 30% of the nitrate fertilizer for the split application of the fertilized, drip-irrigated vines was found in the clusters. The greatest amount of fertilizer N found in the roots was for the nitrate fertilized vines under drip-irrigation (both single and split applications). The results indicated that irrigation type greatly affected RE_N of the N fertilizers used in the study, and that irrigation and fertilizer type affected the distribution of N once it was taken up by the vine.

The fate of fertiliser P in soil under pasture and uptake by subterraneum clover – a field study using 33P-labelled single superphosphate

Single superphosphate (SSP) is a major source of phosphorus (P) used in grazing systems to improve pasture production. The aim of this experiment was to determine the fate of fertiliser P in clover pastures under field conditions. A procedure was developed to radiolabel SSP granules with a 33P radiotracer, which was then applied to the soil surface (equivalent to ~12 kg P ha−1) of a clover pasture. Recovery of fertiliser P was determined in clover shoots, fertiliser granules and soil fractions (surface layer: 0–4 cm and sub-surface layer: 4–8 cm). The P diffusion patterns of the 33P-labelled SSP granules were not significantly different to those of commercial SSP granules (P > 0.05). Recovery of fertiliser P in clover shoots was 30–35 %. A considerable proportion of the fertiliser P (~28 %) was recovered in the surface soil layer and was largely inorganic P. Recovery of fertiliser P by clover plants was up to 35 % in the year of application. Much of the fertiliser P in soil fractions was inorganic P, which highlights the importance of inorganic P forms and dynamics in soils under clover pasture on a single season timeframe at these sites.

The Influenec of Azolla pinnata on Floodwater Chemistry, Grain Yield and Nitrogen Uptake of Rice in Dano, Southwestern Burkina Faso

Nitrogen fertilizer recovery by lowland rice can be as low as 10% and rarely exceeds 60%. Azolla contributes to the nitrogen (N) nutrition of rice plant through biological N fixation (BNF). This study aimed at assessing the influence of Azolla pinatta on floodwater chemistry, rice yield, total dry matter and N uptake of rice. The study was carried out at the Dreyer Research Station in South Western Burkina Faso in 2005 using a split urea application method called Experiment 1 (E1) which was compared with what the farmer’s practice (E2), which is basal application of NPK (16 16 16) and one top-dress of urea. Four levels of nitrogen was used in the experiments (0, 40, 80, 120 kg N ha -1 ). The full Azolla cover on the floodwater surface by the time of urea application prevented rapid increase in floodwater pH in the range of 0.52 to 0.68. The presence of Azolla lowered floodwater temperature by 1.9 to 2.0 o C. There was a significant increased (p 0.05) between Azolla and nitrogen. It is concluded that Azolla brought about an additive effect and could be an efficient fertilizer alternative or supplement in flooded rice cropping system in Dano.

Outworking of the Second Demographic Transition: National Trends and Regional Patterns of Fertility Change in Poland, and England and Wales, 2002-2012

One of the main indicators of the second demographic transition (SDT) is the decline of fertility to below the replacement level (2.1 births per woman). The onset of the SDT in Europe spread across Western Europe in the 1960s and subsequently diffused to other parts of the continent. In Eastern Europe, a fall in total fertility rates below the replacement level was recorded at the beginning of the 1990s and was associated by some researchers with the collapse of the communist system and the introduction of a market economy. At present, countries of Eastern Europe record the lowest total fertility rate values (at 1.3–1.4), whereas a fertility recovery has been observed in Northern and Western Europe. Regional, subnational differences in fertility within particular countries associated with uneven dispersal of changes linked with the SDT, especially between urban, suburban, and rural areas, are known to exist but are less well articulated. This paper offers a comparative study of changes in spatial patterns of selected fertility indicators between Poland, and England and Wales, part of the UK, at the beginning of the 21st century. Despite apparent differences at the national level, the paper identifies similarities in the spread of SDT from core to peripheral areas and presents a reduction in the demographic divide between Western and Eastern Europe. Copyright © 2015 John Wiley & Sons, Ltd.

Biogas slurry concentration hybrid membrane process: Pilot-testing and RO membrane cleaning

The integrated membrane technology, consisting of MF, UF, and RO membrane, was used for the concentration of biogas slurry to realize the recovery of fertilizer and water. The pilot test proved the feasibility of the integrated membrane technology in this application. The RO membrane can concentrate the biogas slurry with the concentration factor of 5. RO membrane shows over 97% removal for COD and NH3-N, allowing less than 50ppm of COD and NH3-N transport to the permeate side. The RO membrane suffered both organic and inorganic fouling. The optimal strategy for eliminating the fouling in this study is the receipt of NaOH+SDS+STPP→HCl. The salt rejection maintained at around 97.0% by this strategy, and the flux recovery had a sharp increase (~50.0%) after the addition of this multiple agent.

Short- and long-term nutritional effects and retention of potassium derived from fertilizer in a sugar maple stand in southern Quebec

The short-term (1–3 years) and long-term (23 years) effects of liming combined with potassium (K) fertilization on forest nutrition and K cycling were examined in a sugar maple (Acer saccharum Marsh.) stand in southern Quebec. Sugar maple leaves were sampled annually from 1988 (prefertilization year) to 1991 and in 2011–2012. Ten understory plant species, sugar maple sapwood, and soils were also sampled in 2012 and analyzed for K, calcium (Ca), magnesium (Mg), and rubidium (Rb). The recovery of fertilizer K was determined using the Rb/K reverse tracer method. Fertilization neither increased growth nor maintained higher sugar maple leaf K levels over the long term; however, leaf K to Ca and K to Mg ratios were still higher in fertilized plots than in control plots in 2012. The percentage of leaf K derived from fertilizer peaked 3 years after fertilization (36% ± 5%) and was down to 1989 levels by 2012 (15% ± 6%). Understory vegetation generally showed no differences in leaf K concentration between treatments, but percent K from fertilizers was greater than 25% in several species. There was no significant effect of fertilization on soil K, Ca, and Mg availability by 2012. Our results suggest that significant amounts of fertilizer K are still present on the site after 23 years but that base cation levels in leaves and upper soil horizons have returned to near prefertilization levels except for a slight enrichment in K. Although small, the effects of fertilization with liming on soil fertility and plant nutrient status in a maple stand can be long lasting.

Nitrogen uptake and nitrogen fertilizer recovery in old and modern wheat genotypes grown in the presence or absence of interspecific competition.

Choosing genotypes with a high capacity for taking up nitrogen (N) from the soil and the ability to efficiently compete with weeds for this nutrient is essential to increasing the sustainability of cropping systems that are less dependent on auxiliary inputs. This research aimed to verify whether differences exist in N uptake and N fertilizer recovery capacity among wheat genotypes and, if so, whether these differences are related to a different competitive ability against weeds of wheat genotypes. To this end, 12 genotypes, varying widely in morphological traits and year of release, were grown in the presence or absence of interspecific competition (using Avena sativa L. as a surrogate weed). Isotopic tracer 15N was used to measure the fertilizer N uptake efficiencies of the wheat genotypes and weed. A field experiment, a split-plot design with four replications, was conducted during two consecutive growing seasons in a typical Mediterranean environment. In the absence of interspecific competition, few differences in either total N uptake (range: 98–112 kg N ha−1) or the 15N fertilizer recovery fraction (range: 30.0–36.7%) were observed among the wheat genotypes. The presence of competition, compared to competitor-free conditions, resulted in reductions in grain yield (49%), total N uptake (29%), and an 15N fertilizer recovery fraction (32%) that were on average markedly higher in modern varieties than in old ones. Both biomass and grain reductions were strongly related to the biomass of the competitor (correlation coefficients > 0.95), which ranged from 135 to 573 g m−2. Variations in both grain and biomass yield due to interspecific competition were significantly correlated with percentage of soil cover and leaf area at tillering, plant height at heading, and total N uptake, thus highlighting that the ability to take up N from the soil played a certain role in determining the different competitive abilities against weed of the genotypes.

Optimal Nitrogen Management Enhanced External Chemical Nitrogen Fertilizer Recovery and Minimized Losses in Soil-Tomato System

Excess chemical nitrogen (N) fertilization is widespread in intensive greenhouse vegetable production in China and has resulted in low recovery efficiency and high losses of chemical N fertilizer. Understanding the fate of chemical N fertilizer is crucial for best management of chemical N fertilizer. Using the technique of stable isotope 15N-labeled urea, a micro-plot experiment was conducted to estimate the recovery of 15N-labeled urea in tomato, residues in soil and losses in soil-tomato system. The treatments included the conventional N management with chemical N rate (1000 kg N/ha), named FP and optimal N management with chemical N rate (500 kg N/ha), combined with maize straw and drip irrigation, named OPT. Compared with the FP, total dry matter yield increased by 6.5%–9.3% for the OPT in the autumn-winter season (AW) and winter-spring seasons (WS), respectively. There was a significantly higher recovery efficiency (20.7%) of 15N-labeled urea in the OPT compared to the FP (11.3%; P < 0.05). The amount of residual NO3--N derived from 15N-labeled urea was significantly higher in the FP than in the OPT (P < 0.05). More inorganic N derived from 15N-labeled urea was incorporated into the stable fraction of organic matter in the OPT and had a positive effect on reducing the N leaching with increased time during the season. The loss rate of N derived from 15N-labeled urea was 46.8% in the FP, 25.8% greater than in the OPT. Optimal N management improved tomato yields, enhanced chemical N recovery efficiency, while minimizing losses in the soil-tomato system. It will be practical for maintaining the sustainability of greenhouse-based intensive vegetable systems.

Generation of a homozygous fertilization-defective gcs1 mutant by heat-inducible removal of a rescue gene.

Key message New gametic homozygous mutants. In angiosperms, a haploid male gamete (sperm cell) fuses with a haploid female gamete (egg cell) during fertilization to form a zygote carrying paternally and maternally derived chromosomes. Several fertilization-defective mutants in Arabidopsis thaliana, including a generative cell-specific 1 (gcs1)/hapless 2 mutant, the sperm cells of which are unable to fuse with female gametes, can only be maintained as heterozygous lines due to the infertile male or female gametes. Here, we report successful generation of a gcs1 homozygous mutant by heat-inducible removal of the GCS1 transgene. Using the gcs1 homozygous mutant as male, the defect in gamete fusion was observed with great frequency; in our direct observation by semi-in vivo fertilization assay using ovules, 100 % of discharged sperm cells in culture failed to show gamete fusion. More than 70 % of ovules in the pistil received a second pollen tube as attempted fertilization recovery. Moreover, gcs1 mutant sperm cells could fertilize female gametes at a low frequency in the pistil. This strategy to generate homozygous fertilization-defective mutants will facilitate novel approaches in plant reproduction research.Electronic supplementary materialThe online version of this article (doi:10.1007/s00497-015-0256-4) contains supplementary material, which is available to authorized users.

Following a site-specific secondary succession in the Amazon using the Landsat CDR product and field inventory data

Secondary forests cover large areas and are strong carbon sinks in tropical regions. They are important for ecosystem functioning, biodiversity conservation, watershed protection, and recovery of soil fertility. In this study, we used the Surface Reflectance Climate Data Record (CDR) product from 16 Thematic Mapper (TM)/Landsat-5 images (1984–2010) to continuously track the secondary succession (SS) of a forest following land abandonment in 1980. Changes in canopy structure and floristic composition were analysed using data from four field inventories (1995, 2002, 2007, and 2012). To characterize variations in brightness, greenness, spectral reflectance, and shadows with the natural regeneration of vegetation, we applied tasselled cap transformations, principal component analysis (PCA), and linear spectral mixture models to the TM datasets. Shade fractions were plotted over time and correlated with the enhanced vegetation index (EVI) and the normalized difference vegetation index (NDVI). Because image texture may reflect the variability of the successional process, eight co-occurrence-based filter metrics were calculated for selected TM bands and plotted as a function of time since abandonment. The successional forest was compared to a nearby primary reference forest (PF) and had differences in the spectral and textural means evaluated using analysis of variance (ANOVA). The results showed increases of 35% and 10.4% over time in basal area and tree height, respectively. Species richness within the assemblage of sampling units increased from 14 to 71 between 1995 and 2012, and this trend was also confirmed using an individual-based rarefaction analysis. Species richness in 2012 was still lower than that observed in the PF site, which presented greater amounts of aboveground biomass (336.4 ± 17.0 ton ha−1 for PF versus 98.5 ± 21.4 ton ha−1 for SS in 2012). Brightness and greenness tasselled cap differences between the SS and PF rapidly decreased from 1984 (SS at the age of 4 years) to 1991 (age of 11 years). Brightness also decreased from 1997 to 2003, as indicated by PC1 scores and surface reflectance of the TM bands 4 (near infrared) and 5 (shortwave infrared). Spectral mixture shade fraction increased from young to old successional stages with strata composition and canopy structure development, whereas NDVI and EVI decreased over time. Because EVI was strongly dependent on near infrared reflectance (r = + 0.96), it was also much more strongly correlated with the shade fraction (r = −0.93) than NDVI. Except for the image texture mean that decreased from young to old successional stages in TM bands 4 and 5, no clear trend was observed in the remaining texture metrics over the time period of vegetation regeneration. Overall, due to structural-floristic and spectral/textural differences with the PF, the SS site was still distinguishable using Landsat data 30 years after land abandonment. Most of the spectral metric means between PF and SS were significantly different over time at 0.01 significance level, as indicated by ANOVA.

Long-Term Effect of Lime, Mycorrhiza, and Inorganic and Organic Sources on Soil Fertility, Yield, and Proximate Composition of Sweet Potato in Alfisols of Eastern India

A field experiment was conducted for five kharif seasons (2006–2011) in an Alfisol to study the effect of integrated use of lime, mycorrhiza, and inorganic and organics on soil fertility, yield, and proximate composition of sweet potato. Application of graded doses of nitrogen, phosphorus, and potassium (NPK) significantly increased the mean tuber yield of sweet potato by 44, 106, and 130 percent over control. Green manuring along with ½ NPK showed greater yield response over that of ½ NPK. The greatest mean tuber yield was recorded due to integrated application of lime, farmyard manure (FYM), NPK, and MgSO4 (13.69 t ha−1) over the other treatments. Inoculation of mycorrhiza combined with lime, FYM, and NPK showed a significant yield response of 10 percent over FYM + NPK. Conjunctive use of lime, inorganics, and organics not only produces sustainable crop yields but also improve soil fertility, nutrient-use efficiency, and apparent nutrient recovery in comparison to NPK and organic manures.