Contribution of tiller age category to herbage accumulation of Marandu palisadegrass under two fertilization regimes

Based on the hypothesis that climate and fertilizers influence the proportion of tiller age categories in the canopy and, consequently, in herbage accumulation, the objective of this study was to determine the population density and the contribution of tiller age categories for herbage accumulation of Urochloa brizantha cv. Marandu during the year and in response to phosphate and nitrogen fertilization. The treatments consisted of two fertilization strategies: low and high fertilization and three tiller ages (young, mature and old), evaluated at four times of the year: winter, early and late spring, and summer. The total number of tillers and the proportion of young tillers were higher in late spring and summer. The growth and herbage accumulation rates showed a typical seasonal pattern and were higher in the canopy under high fertilization. Old tillers contributed more to control the total stem growth rate, as well as the canopy senescence rate. The highest percentage of young tillers is related to the high herbage accumulation in the Marandu palisadegrass canopy.

Optimal Water-Fertilizer Combinations for Efficient Nitrogen Fixation by Sugarcane at Different Stages of Growth

High fertilizer application and over-irrigation in sugarcane systems can cause considerable N2O emissions. Optimized water-fertilization management which reduces N2O emissions, while maintaining sugarcane biomass, is crucial, but may affect nitrogen fixation by sugarcane. This study evaluated the combined effect of water-fertilization on sugarcane biomass and nitrogen fixation in field trials in southern China. Treatments included drip and spray irrigation, with three levels (0% (low), 50% (medium), 100% (high)) of irrigation and of fertilizer. A rain-fed crop (no irrigation or fertilizer) was included as the control. The results showed that (1) spray irrigation with medium water and high fertilization increased biomass. The optimum combination in sugarcane elongation stage was drip irrigation with medium water and high fertilization, while drip irrigation with high water and high fertilization was the best choice for maturity stage. (2) For sugarcane nitrogen (δ15N) content, spray irrigation with medium water and high fertilization was the best combination in seedling and tillering stages. The optimum combination in the elongation stage was drip irrigation with medium water and high fertilization, and in maturity stage was drip irrigation with high water and high fertilization. (3) For soil (δ15N content), drip irrigation with high water and high fertilization proved optimal for seedling, tillering, and maturity stages. (4) In seedling stage, sugarcane (δ15N content) was found to be strongly correlated with leaf area index, soil water, soil temperature, and soil electrical conductivity. Soil (δ15N content) was correlated with photosynthesis and soil temperature. In conclusion, drip irrigation appears most suitable for field planting, while the best treatment in seedling and tillering stages is medium water-high fertilization, and that the best in elongation stage is high water-medium fertilization. The optimum water-fertilizer combinations identified here can provide a scientific basis for optimization and management of irrigation and fertilization in China and other regions with similar environments.

Assessment of the Multiannual Impact of the Grape Training System on GHG Emissions in North Tajikistan

The overarching goal of agricultural sciences is to optimize production technology to rationalize the use of production resources, energy, and space. Due to its high fertilization and water requirements, the vine is a plant with a high potential for greenhouse gas (GHG) emissions. The modifying factor in the production technology is plantation management. To reach the assumed goal, a field experiment was conducted in the years 2001–2020, and the following training systems were used: multi-arm fan system (A) trunk height <30 cm, (B) 80 cm, (C) 120 cm, one-side multi-arm, paired planting (D) 120 cm, (E) 140 cm. The total amount of GHGs emitted in vine cultivation was calculated according to ISO 14040 and ISO 14044 standards. The system boundaries were: establishing the plantation, the production and use of fertilizers and pesticides, energy consumption for agricultural treatments, and gas emissions from the soil. The amount of GHG emissions for cultivation using the systems A, B, C ranged from 426.77 to 556.34 kg of CO2-eq Mg of yield−1, while in the case of D and E systems, the value was approx. 304.37 to 306.23 CO2-eq Mg of yield−1. When comparing this stage with total annual emissions related to cultivation (for 1 ha), the amount of emitted GHGs at this stage is from approx. 42% to 58% higher than from annual emission related to cultivation. Concrete poles are the main element related with GHG emission during stage of plantation establishment, from 97 to 98% of emission. In the case of annual production, nitrogen fertilizers are responsible for approx. 36%. Moreover, the results show that systems D and E increased the average annual fruit yield (per 19 years of research) by approx. 68% compared to the A, B, C systems. There was no difference in the yield of plants with different height of shoots in the D and E systems. The “one-side, multi-arm, paired planting system” was characterized by the highest production and environmental efficiency.

Effects of fertilizer under different dripline spacings on summer maize in northern China

Maximizing grain yields with effective fertilization technologies and minimizing nitrogen losses is essential in agroecosystems. In this research, we conducted a two-year field experiment to explore whether dripline spacing and fertilization rate would affect maize grain yield. Two dripline spacings (i.e., one drip line per row of maize with a row space of 60 cm and one drip line per two rows of maize) and two fertilization rates (i.e., high fertilization level: N, 180 kg ha−1; P2O5, 90 kg ha−1; and K2O, 90 kg ha−1 and low level: N, 139.5 kg ha−1; P2O5, 76.5 kg ha−1; and K2O, 76.5 kg ha−1) were employed in this research. The results showed that maize yield was significantly affected by both dripline spacing and fertilization rate. The maize yield was 10.2% higher in the treatment with one drip line per two rows than that in the treatment with one drip line per row. Maize yield increased by 10.9% at the high fertilization level compared to that at the low fertilization level. The quantity of cumulative ammonia volatilization was reduced by 15.1% with one drip line per two rows compared to that with one drip line per row, whereas it increased by 26.9% at the high fertilization level compared with that at the low fertilization level. These results indicated that one drip line per two rows with a high fertilization rate increased the yield and could reduce the environmental burden, which may be economically beneficial and environmentally sound for maize fertigation for green agricultural development.

Dissecting the subtropical adaptation traits and cuticle synthesis pathways via the genome of the subtropical blueberry Vaccinium darrowii

Vaccinium darrowii is a subtropical wild blueberry species, which was used to breed economically important southern highbush cultivars. The adaptation traits of V. darrowii to subtropical climate would provide valuable information for breeding blueberry and perhaps other plants, especially against the background of global warming. Here, we assembled the V. darrowii genome into 12 pseudochoromosomes using Oxford Nanopore long reads complemented with Hi-C scaffolding technologies, and predicted 41 815 genes using RNAseq evidence. Syntenic analysis across three Vaccinium species revealed a highly conserved genome structure, with the highest collinearity between V. darrowii and V. corymbosum. This conserved genome structure may explain the high fertilization during crossbreeding between V. darrowii and other blueberry cultivars. Gene expansion and tandem duplication analysis indicated possible roles of defense and flowering associated genes in adaptation of V. darrowii to the subtropics. The possible SOC1 genes in V. darrowii were identified with phylogeny and expression analysis. Blueberries are covered in a thick cuticle layer and contain anthocyanins, which confer their powdery blue color. Using RNA-sequencing, the cuticle biosynthesis pathways of Vaccinium species were delineated here in V. darrowii. This result could serve as a reference for breeding berries with customer-desired colors. The V. darrowii reference genome, together with the unique traits of this species, including diploid genome, short vegetative phase, and high compatibility in hybridization with other blueberries, make V. darrowii a potential research model for blueberry species.

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.

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.

Different Timings of Early Cumulus Cells Removal Have Different Multiple Pronuclei Rates in Human in Vitro Fertilization

Background: Cumulus cells removal 4 h post-insemination has a significantly higher multiple pronuclei (MPN) rate than cumulus cells removal 20 h post-insemination. And, cumulus cells removal 6 h post-insemination has a significantly lower MPN rate than cumulus cells removal 20 h post-insemination. However, it remains unclear whether the different timings of early cumulus cells removal, such as the timings of 4, 5 and 6 h post-insemination, have significantly different MPN rates.Methods: This was a retrospective study. The included cycles were early cumulus cells removal cycles (n=752) at our center from January 2015 to August 2020. The included cycles were divided into two groups according to whether MPN exist (MPN=0% and MPN>0%). The patient and cycle stimulation characteristics of the two groups were compared. Binary logistic regression was performed to investigate the correlation between the timing of early cumulus cells removal and MPN. The cohort study was also performed to compare the patient characteristics, cycle stimulation characteristics, fertilization outcomes, and cultivation outcomes.Results: In the population of our study, the timing of early cumulus cells removal had a significant effect on the MPN. The cumulus cells removal ≤4 h post-insemination group had a high MPN rate, and the 5.5<time≤6 h group had a high fertilization failure rate. However, 2PN rate was not significantly different among the different timings of early cumulus cells removal. In addition, the ≤4 h post-insemination group had a high grade 1–2 embryo rate at day 3.Conclusion(s): Even if all the timings of cumulus cells removal are early, the different timings of early cumulus cells removal still have a significant effect on the MPN.

Resource-Saving Technology Based on Sewage Sludge

The issues of waste disposal are currently having a global technological and economic complexity. The severity of the environmental problem is specified by the accumulation of large volumes of various wastes, including sewage sludge (SS). Modern technologies can provide its disposal with environmental and economic benefits. SS is a rich source of nutrients with a high fertilization potential. This work aims to study the utilization of wastewater sludge in recycling technology for agriculture. The composition of urban sewage sludge and its impact on the properties of gray forest soil were studied. It was shown that its application in a dose of 40-60 t/ha promoted an increase in the content of humus, mobile phosphorus and exchangeable potassium in the soil and a decrease in acidity. The noted increase in the content of the studied heavy metals upon the introduction of various doses of sludge did not exceed the approximate permissible concentration (APC) in the soil. The results showed that the use of SS as a fertilizer restores the balance of organic matter in soils and improves their agroecological properties. This technology, as a safe way of recycling waste into a valuable complex fertilizer, contributes to resource conservation.