Intercropping soybean and palisade grass for enhanced land use efficiency and revenue in a no till system

Integrated no-till crop and livestock production systems may help rejuvenate degraded pastures, increase land use efficiency (LUE), and increase enterprise revenue. Our objectives were to evaluate: (1) planting date effects on seed yield and nutrient concentration of an early-maturing, no-till system (NTS) soybean (Glycine max) when intercropped with palisade grass (Brachiaria brizantha); (2) dry matter production and protein concentration of the grass pasture after soybean harvest; and (3) overall revenue and LUE for the intercrop system. Experiments were performed during two growing seasons in Botucatu, Brazil using a randomized complete block experimental design. When palisade grass and soybean were sown simultaneously, soybean yield averaged 3.28 Mg ha⁻¹. Similar seed yields were observed when palisade grass was planted either 30 d after soybean emergence (DAE) (3.29 Mg ha⁻¹) or at the soybean reproductive stage R6 (full seed) (3.50 Mg ha⁻¹). Monocrop soybean yield averaged 3.50 Mg ha⁻¹. First cut dry matter forage production was greater when palisade grass was sown at the same time as soybean or 30 DAE of soybean. This indicates that interseeding palisade grass with soybean does not significantly affect soybean nutrition or yield. Intercropping did increase LUE and resulted in 1.6 times more revenue than soybean alone. However, sowing palisade grass at the soybean reproductive stage R6 (full seed) significantly reduced the forage yield compared to early planting.     

Plant functional types rather than climate or soil determine leaf traits in the forest biomes of eastern China

Nitrogen (N) has great ecological importance, but the biogeographic pattern across forest biomes in China has only recently been explored. Here we conducted a systematic census of leaf C and N following the same protocol to explore the variations of leaf traits, and their possible responses to plant functional types (PFTs) and environmental factors. Results showed that leaf traits varied substantially across biomes, and the relationships of PFTs to climatic factors were stronger than those of PFTs versus soil nutrient proxies, indicating that plant species composition might be a better predictor of plant species distribution with climate than leaf traits. Soil nutrient proxies explained more variation of leaf traits than climate, which demonstrates that leaf traits reflect important aspects of plant responses to soil nutrients. Importantly, partial general linear models analyses found that PFTs showed the greatest direct influence for leaf traits, and climate and soil affected leaf traits mainly through the change in plant species composition rather than having direct impacts. Hence, we concluded that leaf traits were largely controlled by PFTs rather than climate or soil at the biome scale. The results favored the species composition hypothesis, indicating that leaf nutrient concentration is mainly determined by PFTs.     

Immobilization,cardiopulmonary and blood gas effects of ketamine–butorphanol–medetomidine versus butorphanol–midazolam–medetomidine in free-ranging serval (Leptailurus serval)

ObjectiveTo compare ketamine–butorphanol–medetomidine (KBM) with butorphanol–midazolam–medetomidine (BMM) immobilization of serval.Study designBlinded, randomized trial.AnimalsA total of 23 captures [KBM: five females, six males; 10.7 kg (mean); BMM: 10 females, two males; 9.6 kg].MethodsServal were cage trapped and immobilized using the assigned drug combination delivered via a blow dart into gluteal muscles. Prior to darting, a stress score was assigned (0: calm; to 3: markedly stressed). Drug combinations were dosed based on estimated body weights: 8.0, 0.4 and 0.08 mg kg^–1 for KBM and 0.4, 0.3 and 0.08 mg kg^–1 for BMM, respectively. Time to first handling, duration of anaesthesia and recovery times were recorded. Physiological variables including blood glucose and body temperature were recorded at 5 minute intervals. Atipamezole (5 mg mg^–1 medetomidine) and naltrexone (2 mg mg^–1 butorphanol) were administered intramuscularly prior to recovery. Data, presented as mean values, were analysed using general linear mixed model and Spearman’s correlation (stress score, glucose, temperature); significance was p < 0.05.ResultsDoses based on actual body weights were 8.7, 0.4 and 0.09 mg kg^–1 for KBM and 0.5, 0.4 and 0.09 mg kg^–1 for BMM, respectively. Time to first handling was 10.2 and 13.3 minutes for KBM and BMM, respectively (p = 0.033). Both combinations provided cardiovascular stability during anaesthesia that lasted a minimum of 35 minutes. Recovery was rapid and calm overall, but ataxia was noted in KBM. Stress score was strongly correlated to blood glucose (r² = 0.788; p = 0.001) and temperature (r² = 0.634; p = 0.015).Conclusions and clinical relevanceBoth combinations produced similar effective immobilization that was cardiovascularly stable in serval. Overall, BMM is recommended because it is fully antagonizable. A calm, quiet environment before drug administration is essential to avoid capture-induced hyperglycaemia and hyperthermia.     

Iron fertilizers applied to calcareous soil on the growth of peanut in a pot experiment

A greenhouse pot experiment was conducted with peanuts (Arachis hypogaea L., Fabceae) to evaluate iron compound fertilizers for improving within-plant iron content and correcting chlorosis caused by iron deficiency. Peanuts were planted in containers with calcareous soil fertilized with three different granular iron nitrogen, phosphorus and potassium (NPK) fertilizers (ferrous sulphate (FeSO₄)–NPK, Fe–ethylendiamine di (o-hydroxyphenylacetic) (EDDHA)–NPK and Fe–citrate–NPK). Iron nutrition, plant biomass, seed yield and quality of peanuts were significantly affected by the application of Fe–citrate–NPK and Fe–EDDHA–NPK to the soil. Iron concentrations in tissues were significantly greater for plants grown with Fe–citrate–NPK and Fe–EDDHA–NPK. The active iron concentration in the youngest leaves of peanuts was linearly related to the leaf chlorophyll (via soil and plant analyzer development measurements) recorded 50 and 80 days after planting. However, no significant differences between Fe–citrate–NPK and Fe–EDDHA–NPK were observed. Despite the large amount of total iron bound and dry matter, FeSO₄–NPK was less effective than Fe–citrate–NPK and Fe–EDDHA–NPK to improve iron uptake. The results showed that application of Fe–citrate–NPK was as effective as application of Fe–EDDHA–NPK in remediating leaf iron chlorosis in peanut pot-grown in calcareous soil. The study suggested that Fe–citrate–NPK should be considered as a potential tool for correcting peanut iron deficiency in calcareous soil.     

Root zone selenium reduces cadmium toxicity by modulating tissue-specific growth and metabolism in maize (Zea mays L.)

The effects of selenium (Se) cadmium (Cd) interactions on plant growth and metabolism are not fully clear. In the present study, we assessed whether Se could alleviate the toxic effects of Cd on growth and metabolism of maize. Seeds of maize variety FH-985 were sown in pots filled with sand treated with CdCl₂ (0, 50 and 100 µM) and Se (0, 2 and 4 mg L^?1) through Hoagland’s nutrient solution. Low Se (2 mg L^?1) increased germination percentage and rate, while high Se (4 mg L^?1) increased fresh and dry biomass under Cd stress. Interestingly, all Se concentrations were effective in alleviating the toxic effects of Cd on photosynthetic pigments, whereas higher Se mitigated the Cd-induced oxidative stress and increased flavonoids both in the shoots and roots while phenolics in the roots. The results demonstrated that root zone Se altered tissue-specific primary metabolism in maize. Furthermore, low Se mitigated the Cd-induced decrease in total proteins in the root. Overall, Se-mediated decrease in the oxidative stress in the shoots while increase of secondary metabolites in the roots helped the plants to grow faster at early growth stage and caused increase in the biomass under different Cd regimes.     

基于UHPLC–QTOF–MS技术的五倍子单宁成分分析

目的 基于超高效液相色谱–四极杆飞行时间–质谱（UHPLC–QTOF–MS）技术分析五倍子中单宁成分,建立一种有效的五倍子单宁成分测定方法,并解析单宁的裂解规律。 方法 使用高温和超声波辅助方法提取五倍子中的酚类化合物,基于二级质谱推定化合物的裂解途径。 结果 共鉴定到20种化合物,包含14种没食子单宁、3种酚酸、2种没食子酸酯和1种黄烷醇。以高温121℃为提取条件,均未鉴定到分子质量高于1 500 Da的没食子单宁,而在超声波辅助提取的五倍子水提取液中,成功地检测到1–O–没食子酰基葡萄糖至14–O–没食子酰基葡萄糖,其中,超声功率1 500 W,提取温度65℃条件下,鉴定到更多的没食子单宁异构体。MS/MS图谱显示,五倍子单宁主要通过没食子酸、没食子酰基、糖苷、水、羧基的损失进行裂解。 结论 本研究证明,超声波辅助提取条件下,应用UHPLC–QTOF–MS技术能够全面高效地分析五倍子中的单宁成分,本研究为富含单宁的植物的化学成分研究提供参考依据。     

Effect of variable retention cutting on the relationship between growth of coarse roots and stem of Picea mariana

Silviculture heading for structural heterogeneity creates many single trees standing at stand margins, inner edges or in remnant tree groups. As they played just a minor role in the age class forest, the growth behaviour of strongly released trees is rather unexplored. Here we show how retention cutting, presently spreading in the boreal of Québec province, affects stem and coarse root growth of remained single black spruce [Picea mariana (Mill.) Britton]. Increment cores from roots and stems of 125 trees show that retention cutting triggers coarse root growth of the remaining trees. Compared with reference trees retention trees accelerate root in relation to stem growth. Mean and variability of the root–stem allometry significantly rise after retention cutting. The found acceleration of root in relation to stem growth means mechanical stabilisation of the retention trees and corroborates the retention cutting method. Evaluation of silvicultural treatments can be incomplete and misleading as long as they are just based on aboveground reactions and neglect root growth.     

Effects of Long-Term Fertilizer Application and Rainfall Distribution on Cotton Productivity,Profitability, and Soil Fertility in a Semi-arid Vertisol

Long-term fertilizer experiments were conducted on cotton (Gossypium hirsutum) for 21 years with eight fertilizer treatments in a fixed site during 1987–2007 to identify an efficient treatment to ensure maximum yield, greater sustainability, monetary returns, rainwater-use efficiency, and soil fertility over years. The results indicated that the yield was significantly influenced by fertilizer treatments in all years except 1987 1988, and 1994. The mean cotton yield ranged from 492 kg ha^?1 under the control to 805 kg ha^?1 under 25 kg nitrogen (N) [farmyard manure (FYM)] + 25 kg N (urea) + 25 kg phosphorus (P) ha^?1. Among the nutrients, soil N buildup was observed with all treatments, whereas application of 25 kg N + 12.5 kg P ha^?1 exhibited increase in P status. Interestingly, depletion of potassium (K) was recorded under all the fertilizer treatments as there was no K application in any of the treatments. An increase in soil N and P increased the plant N and P uptake respectively. Using relationships of different variables, principal component (PC) analysis technique was used for assessing the efficiency of treatments. In all the treatments, five PCs were found significant that explained the variability in the data of variables. The PC model of 25 kg N (FYM) + 25 kg N (urea) + 25 kg P ha^?1 explained maximum variability of 79.6% compared to other treatments. The treatment-wise PC scores were determined and used in developing yield prediction models and measurement of sustainability yield index (SYI). The SYI ranged from 44.4% in control to 72.7% in 25 kg N (FYM) + 25 kg N (urea) + 25 kg P ha^?1, which attained a mean cotton yield of 805 kg ha^?1 over years. Application of 25 kg N (FYM) + 25 kg N (urea) + 25 kg P ha^?1 was significantly superior in recording maximum rainwater-use efficiency (1.13 kg ha^?1 mm^?1) and SYI (30.5%). This treatment also gave maximum gross returns of Rs. 30272 ha^?1 with benefit–cost ratio of 1.60 and maintained maximum organic carbon and available N, P, and K in soil over years. These findings are extendable to cotton grown under similar soil and agroclimatic conditions in any part of the world.     

Grain legume effects on soil nitrogen mineralization potential and wheat productivity in a Mediterranean environment

The objective of this work was to provide evidence on the effects of faba bean (Vicia faba L.) and chickpea (Cicer arietinum L.) on the dynamics of soil N availability and yield parameters of wheat (Triticum turgidum L. var. durum) in a legume–wheat rotation in comparison with the effects of the more extensively studied common vetch (Vicia sativa L.). Soil samples were taken from field plots just before wheat sowing and incubated in the laboratory to assess N mineralization potential, soil respiration and N immobilization after incorporation of legume residues. Soil after vetch cultivation showed the highest residual N and mineralization potential (120 mg N kg^?1 soil), the greatest CO₂ release and the smallest N immobilization. Smaller mineral N release (80 mg N kg^?1 soil) was shown by soil after faba bean cultivation, which, however, would be capable to support an average wheat production without fertilization. Soil after chickpea and wheat cultivation manifested no differences in residual N and mineralization or immobilization potential. Laboratory results were well correlated with grain yield and N uptake during the second season of rotation in the field. All legumes resulted in significant yield surpluses and provided N credit to the following unfertilized wheat.     

Performance Assessment of Chlorophyll Meter to Determine When to Irrigate Wheat under Different Soil Moisture Deficit Conditions: An Initial Study

ABSTRACT

Proper irrigation timing can minimize the negative impacts that reduce crop yields. Therefore, in an initial pot experimental study, we assessed the SPAD (Soil–Plant Analysis Development)-chlorophyll meter as a tool to determine proper irrigation timing of wheat under different soil water deficit conditions in a controlled-environment greenhouse. The treatments were controlled irrigation at 100% (T₁), 70% (T₂), 50% (T₃) and 30% (T₄) of soil water content at field capacity; and the growth stages were development, mid-season and late-season. SPAD readings were measured pre-irrigation events. The results indicated that the T₃ and T₂ achieved maximum grain yield per accumulated crop evapotranspiration, i.e. water productivity (0.82 and 0.76 kg m^?3), and were at par with T₁. Moreover, the SPAD readings had a high Pearson’s correlation coefficient with crop evapotranspiration (r = 0.95; P ≤ 0.001) and wheat grain yield (r = 0.90; P ≤ 0.001), indicating that SPAD reading could be used to reliably estimate when to irrigate wheat. Therefore, T₃ and T₂ SPAD readings were averaged to estimate a target limit at which irrigation should be applied. Accordingly, the target limit was defined as >44.76 for the development stage, >50.72 for the mid-season stage, and >37.64 for the late-season stage; readings below this target limit indicate that it is time to irrigate.