Higher Physiological Efficiency Research Articles

Effect of nitrogen fertilizer on nitrogen use efficiency and yield of selected sorghum genotypes in semi-arid regions of Kenya

Sorghum production in semi-arid lands is constrained by inadequate soil moisture and low nitrogen. Research was carried out between 2018-2020 to determine the effect of nitrogen fertilizer on nitrogen use efficiency, yield on selected sorghum genotypes and genotypes suitable for low soil fertility in semi-arid lands. The experiment was a randomized complete block design in a split-plot arrangement with 11 sorghum genotypes in the main plot and nitrogen (0, 6.5 and 32.5 kgha-1) as the sub-plots in three replicates. Nitrogen use efficiency (NUE) and its indices agronomic efficiency (AE), nitrogen internal utilization (IE), physiological efficiency (PE), nitrogen recovery efficiency, nitrogen harvest index (NHI) and partial factor productivity (PFP) were obtained from sorghum yield data and nitrogen uptake. The results showed that nitrogen application at 6.5 kgha-1 and 32.5 kgha-1 significantly increased grain yield, stover weight and total dry matter (TDM) by 43% and 116%, 39% and 85% and 42% and 57% respectively. Sorghum genotypes TTKKIAMA6, KTIRASTAMMA4, SNYAKTOSA5, and MKNKKIRWMA2 had significantly higher grain yield and low N uptake implying they are N-efficient. NUE of sorghum decreased with increasing N application. Nitrogen internal utilization efficiency (IE) was significantly higher at zero N application rate implying better N assimilation by sorghum genotypes at low N. AE, PE, RE and PFP were all significantly higher at 6.5 kg N ha-1. All tested genotypes had significantly high NUE (90 to 1148 kgkg-1, RE (27 to 94 kgkg-1), AE (41 to 139 kgkg-1), PE (27 to 84 kgkg-1) and IE (41 to 139 kgkg-1) than the check (Gadam). It was concluded that sorghum genotypes yield parameters were increased by nitrogen application, NUE was highest at low N levels and its indices were significantly higher at 6.5 kg Nha-1. Four genotypes were found to be highly N-efficient and are recommended for sorghum improvement.

Rice Production and Nitrogen Use Efficiency in Different Nitrogen Management Systems Under Sub-Humid Conditions

ABSTRACT A two-year experiment study was conducted at CSK HPKV, Rice, and Wheat Research Center, Malan, Himachal Pradesh, India, on silty clay loam soil during kharif 2016 and 2017. Application of highest dose of nitrogen i.e. 125% recommended dose of nitrogen (RDN) through neem-coated urea (NCU) in three splits recorded maximum grain (5.16 t ha−1) and straw yield (6.37 t ha−1), and this treatment also proved better in terms of absolute growth rate, relative growth rate, crop growth rate, nitrogen, phosphorus and potassium content and uptake and apparent recovery efficiency over rest of the treatments. However, application of 75% RDN through NCU in three splits obtained higher agronomic efficiency (27.07 kg kg−1), utilization efficiency (35.72 kg kg−1), agro physiological efficiency (43.31 kg kg−1), and partial factor productivity (72.14 kg kg−1). The higher physiological efficiency (73.44 kg kg−1) was obtained with application of 100% RDN through NCU in three splits. Soil available nitrogen decreased over initial value, irrespective of the treatments. 125% RDN through NCU when applied in three splits recorded higher available soil nitrogen (449.5 kg ha−1) as well as soil available potassium (257.6 kg ha−1) while soil available phosphorus improved over initial value with highest value (49.5 kg ha−1) observed with 75% RDN through NCU in three splits.

Controlled nitrogen transformation in chemo-amended urea improves nitrogen use efficiency and productivity of wheat grown on alkaline calcareous soil.

Low wheat production is linked to soil degradation, low organic matter, temperature variation, and nutrient depletion in soils of semiarid regions. Nitrogen is mostly applied as urea to meet crop requirements; however, excessive N application may pollute the environment and contaminate groundwater. The current studies explored possible ways for decreasing N losses (NH3 volatilization and NO3 leaching) and improving N availability for wheat production in alkaline soil. The ZnO was coated on urea (1% Zn coating) to get zinc-coated urea (ZnU), and both urea and ZnU were incubated in laboratory at recommended rate (RR), i.e., 150kgNha-1 and 80% (N of RR), after further coating with inhibitors [N-(n-butyl) thiophosphoric triamide (NBPT) at 1% of urea and 4-amino-1,2,4-triazole (ATC) at 2% of urea], thus creating six treatments. The results showed higher NH3-N loss at day 4 and thereafter a decreasing trend reaching to minimum at day 14. The cumulative NH3-N volatilization from urea alone was found higher (28.99%), except ATC treatments producing statistically similar losses due to restriction in nitrification process. In greenhouse, the treatments were tested in wheat cultivars (Faisalabad 2008 and Lasani) for crop growth, nutrient (N, P, K, and Zn) uptake, and yield parameters, where 80% of RR treatment, i.e., NBPT + ZnU80, was found at par with full RR as commercial products, especially comparable to ZnU (at RR) that produced the highest chlorophyll (53.65unit value), net leaf photosynthetic rate (19.64μmol CO2 m-2s-1), plant biomass (208.13g/pot), grain yield (63.65g/pot), and nutrient (NPK and Zn) accumulation in grain of Fsd-2008 cultivar. In field trial, NBPT + ZnU80 also outperformed and produced the highest physiological efficiency (PE), agronomic efficiency (AE), and nitrogen recovery efficiency (REN); the treatment also found statistically similar with ZnU (at RR) that produced the maximum plant height (95.4cm), plant biomass (11.58 t/ha), grain yield (4.69 t/ha), and 1000-grain weight (42.55g). The relative NO3 leaching was found lower in 80% N treatments, yet leaching was not significant from either treatment at the three stages of crop growth. Overall, current studies revealed the effectiveness of NBPT-amended urea (followed by ZnU) with 20% saving of N inputs through higher N availability for plant uptake that could benefit growers as well as conserve environment.

Short Communication Physiological Efficiency and N Recovery of Wheat Influenced by Different N Sources Under Naturally Salt-Affected Soil

A field study was conducted to investigate the effect of different N fertilizer sources (urea, nitrophos, ammonium sulphate and calcium ammonium nitrate) on the productivity of wheat (var. Inqlab) in naturally salt-affected soil (pH = 8.79; ECe = 6.46; Sandy loam). A significant difference was observed in wheat grain and straw yield with the application of different N sources. Maximum wheat grain and straw yields (3203 and 3489 kg/ha, respectively) were recorded when ammonium sulphate was applied. Various N sources followed the order: Ammonium sulphate > urea > calcium ammonium nitrate and/or nitrophos. Comparatively higher N uptake by wheat (117.26 and 114.00 kg/ha) was observed with Ammonium sulphate and urea application, respectively. Similarly, maximum N recovery was observed with both these N sources followed by nitrophos, and calcium ammonium nitrate. However, the highest physiological efficiency (14.29 kg/kg fertilizer applied) was noted with the application of ammonium sulphate.

Nutrient uptake and use efficiency of onion seed yield as influenced by nitrogen and phosphorus fertilization

The experiment was conducted at Kulumsa, South East Ethiopia, using four levels of nitrogen (N) (0, 50,100 and 150 kg N ha−1) and four levels of phosphorus (P) (0, 35, 70 and 105 kg P2O5 ha−1) fertilizers arranged in 4 × 4 factorial arrangements in randomized complete block design with three replications. The available P was increased after harvest due to the application of N and P fertilizer at the rates of 100 or 150 kg N ha−1 and 70 or 105 kg P2O5 ha−1. More specifically, nutrients concentration and nutrient uptake were significantly (p < .01) varied among treatment combinations and nutrient use efficiency was declined by increasing N and P after optimum rates. The higher physiological efficiency of N (53.47 kg kg−1) and P (580.41 kg kg−1) and the highest apparent recovery of N (19.62%) and P (2.47%) was recorded from application of 50 kg N ha−1 and P at 70 kg P2O5 ha−1 and the highest agronomic efficiency of N (10.78 kg kg−1) and P (15.25 kg kg−1) was recorded from N at the rate of 50 kg N ha−1 and P at 35 kg P2O5 ha−1, respectively. The combination of N at 100 kg N ha−1 and P at 70 kg P2O5 ha−1 was promising combination that generated highest net benefit 488,878.5 ETB (Ethiopian birr) ha−1 with the highest marginal rate of return (36638%) and gave the highest seed yield (1858.82 kg ha−1) with yield increment of about 57.72% over the control.

Zinc Accounting for Lowland Rice (Oryza sativa L.) Under Different Methods of Zinc Application with Green Leaf Manuring

Zinc is the common micronutrient; its availability is reduced under lowland rice cultivation. Field investigation was carried out at during winter (Rabi) season of 2016-17 at Agricultural College and Research Institute, killikulam, Tamil Nadu Agricultural University. The zinc use efficiencies were positively influenced the by the application of zinc as basal and foliar spray at critical stages of rice. The higher physiological efficiency recorded by zinc applied as basal with green leaf manuring. The zinc induced nitrogen use efficiency was noted higher at zinc applied as soil plus foliar application with green leaf manuring. The agronomic efficiency, partial factor productivity and zinc recovery fraction (apparent recovery) was higher under application of zinc as foliar spray twice with green leaf manuring. Incorporation of green leaf manure of Glricidia maculate was favorable influence of increasing use efficiency of applied zinc.

Evaluation of groundnut genotypes for physiological efficiencyand high yield to suit early kharif situation

Groundnut is grown during July to October in kharif season, however area under early kharif (sowing in May) is increasing in Andhra Pradsh, where ever irrigation facilities exists. Hence to identify suitable variety for the situation, fourteen pre release and two released groundnut genotypes were evaluated during early kharif 2013 for growth, physiological traits and yield attributes. At harvest genotypes TCGS-1375 (41.331 g plant-1), TCGS-1342(41.059 g plant-1) significantly recorded higher total dry matter compared to all other cultivars and checks followed by TCGS-1330 (36.667 g plant-1), TCGS-1349 (36.433 g plant-1). TCGS-1342 recorded significantly higher Crop Growth Rate (CGR) value of 33.848 g m-2 day-1, where as TCGS-1346 (0.1265 g dm-2 day-1) and TCGS-1330 (0.1262 g dm-2 day-1) recorded significantly higher Net Assimilation Rate (NAR) values at 45-60 DAS. Cultivar, TCGS-1330 recorded significantly higher pod yield 4210.44 Kg ha-1 compared to other entries and checks. The results revealed that pre release genotypes, TCGS-1342, TCGS-1375, TCGS-1330, TCGS-1346 recorded high physiological efficiency in terms of growth and physiological traits viz. total dry matter (TDM), crop growth rate (CGR), net assimilation rate (NAR) and leaf area index (LAI) and also recorded high pod yield.

Effects of gender and socioeconomic status of older people on the execution of the 6 minute walk test

The six minute walk test (6MWT) is an important physical performance measure used in older people. To assess the total distance walked and the physiological cost of the 6MWT in non-disabled older people. Fifty six females aged 69 ± 5 years with a body mass index (BMI) of 31 ± 4 kg/m² and sixteen males aged 70 ± 7 years with a BIM of 29 ± 4 kg/m² underwent a 6MWT. The total distance walked was registered and the physiological cost (PC) of the test was calculated as the ratio between the difference of heart rate at work and at rest and the walking speed. The socioeconomic status (SES) of participants was determined using a questionnaire designed in Chile. Among participants of middle-lower and middle-upper SES, the PC was 0.43 ± 0.1 and 0.44 ± 0.09 beats/min, respectively, p = NS. Males of middle-upper SES had a significantly higher PC than their middle-lower SES counterparts. The total distance walked was 493 ± 58 and 501 ± 63 m among participants of upper and lower SES. The plateau in reserve heart rate appeared earlier among participants of upper SES of both genders. Older participants of middle-upper SES had a higher physiological efficiency during the execution of the 6MWT.

Nitrogen Use Efficiency of Low Land Rice as Affected by Organic and Chemical Sources

Given the increasing dairy and poultry industries, cowdung (CD) and poultry manure (PM) might become alternative sources of nitrogen (N) for rice production in South Asia. A field experiment was conducted during dry season (November-April) in Gazipur, Bangladesh. The experiment aimed to evaluate N use efficiency (NUE) in rice under varying sources of N application. Six treatments—1) N-control; 2) optimum dose of nitrogen (164 kg N ha﹣1) from urea; 3) 50% N from urea and 50% N from CD; 4) 50% N from urea and 50% N from PM; 5) 100% N from CD; and 6) 100% N from PM— were compared. Two mega varieties—BRRI dhan28 and BRRI dhan29—were used as test crops. In BRRI dhan28, the urea treatment had the highest agronomic use efficiency (AUE), utilization efficiency (UE) and partial factor productivity (PFP) followed by urea PM treatment and absolute PM treatment. In BRRI dhan29, the urea PM treatment had the highest AUE followed by absolute urea treatment while the urea PM treatment gave the highest UE and PFP followed by urea treatment and urea CD treatment. The absolute PM treatment gave the highest physiological efficiency (PE) followed by absolute urea treatment in BRRI dhan28. In BRRI dhan29, the absolute PM treatment had the highest PE followed by urea treatment and urea PM treatment. The absolute PM treatment had the highest agro physiological efficiency (APE) both in BRRI dhan28 and BRRI dhan29. Based on this finding, it is concluded that the practice of integrated use of organic and chemical fertilizer has the scope to reduce chemical fertilizer and also contribute to increasing nitrogen use efficiency.

ENRICHMENT OF BASMATI RICE GRAIN AND STRAW WITH ZINC AND NITROGEN THROUGH FERTI-FORTIFICATION AND SUMMER GREEN MANURING UNDER INDO-GANGETIC PLAINS OF INDIA

Zinc (Zn) deficiency is a well-identified problem in cereals, resulting in decreased crop yields and nutritional quality. Approximately half of the world's population suffers from Zn deficiency. Cereal crops play an important role in satisfying daily calorie intake in developing world, but they are inherently very low in grain-Zn concentrations, particularly when grown under Zn-deficient soils. Therefore, it is essential to increase the Zn concentration in cereal grains particularly in basmati rice. Application of Zn fertilizers or Zn-enriched [nitrogen (N)- phosphorus (P)- potassium (K)] fertilizers (ferti-fortification) offers a rapid solution for increasing Zn concentration in grain and straw. The present study was therefore undertaken to study nutrient concentrations in grain and straw, their uptake and use-efficiencies as influenced by summer green manuring (SGM) and Zn fertilization. Field experiments were conducted for two consecutive years during summer and rainy (Kharif) seasons (April–November) of 2008 and 2009; indicated that SGM and Zn fertilization had significant effects on concentrations and uptake of N, K, sulfur (S), Zn, manganese (Mn), copper (Cu), and iron (Fe) in basmati rice grain and straw. Amongst the SGM and Zn fertilization treatments, Sesbania aculeata green manuring (GM) and 2.0% Zn-enriched urea (ZEU) as zinc sulfate (ZnSO4.H2O) recorded the highest N, K, S, Mn, Cu, and Fe concentrations, and their uptake in grain and straw as well as total (grain + straw) of basmati rice compared to rest of the SGM crops and Zn fertilization treatments. In regards to Zn concentration, foliar spray of 0.2% (ZnSO4.H2O) recorded the highest values of Zn concentration in grain and straw viz. 24.1, 24.1 and 177.7, and 179.2 mg kg−1 DM during 2008 and 2009, respectively. Whereas, 2.0% ZEU as ZnSO4.H2O recorded the highest total Zn uptake viz. 3081.6 and 3089.0 g ha−1 in 2008 and 2009, respectively. The estimated values viz. partial factor productivity (PFP) and crop recovery efficiency (CRE) of applied N were the highest with Sesbania aculeata GM and 2.0% ZEU as ZnSO4.H2O treatments. But, the highest physiological efficiency (PE) of applied N was obtained after summer fallow and control (only N) viz. 25.7, 20.1 and 27.1, and 21.9 kg grain kg−1 of N absorbed in 2008 and 2009. All the Zn-use indices were also influenced significantly due to SGM crops and Zn fertilization treatments except ZnHI of basmati rice. Agronomic efficiency (AE) of applied Zn to rice crop was significantly higher with mungbean (Vigna radiata) GM and ZnO slurry Zn fertilization treatment, however, 0.2% foliar spray of ZnSO4.H2O recorded the highest Zn crop recovery efficiency (Zn CRE) viz. 57.6 and 61.6%, respectively. Overall, application of Zn fertilizer (ferti-fortification) to basmati rice through ZEU and foliar spray of 0.2% (ZnSO4.H2O) increased Zn concentration in grain and straw, resulting in greater bio-availability of grain Zn. Therefore, this would be a very important and useful strategy in solving the Zn deficiency related problems in Indo-Gangetic plains of India.

Evaluation of low-energy demand adaptive mechanisms in Sangiovese grapevine during drought

&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Aims&lt;/strong&gt;: The aim of this paper is to evaluate the photoinhibition capability, CO2 fixation activity and some adaptive mechanisms external to the photosystem II reaction centres in Sangiovese grapevine subjected to drought conditions.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Methods and results&lt;/strong&gt;: The diurnal time courses of gas-exchange and chlorophyll fluorescence parameters were monitored on free (natural position) and artificially retained (horizontal) leaves in Sangiovese potted vines maintained at 90 % and 40 % of maximum water availability from fruit-set to veraison. Changes in leaf and shoots characteristics were also monitored. Under drought, the inhibition of photosystem II in Sangiovese leaves may be severe and persistent according to leaf position (basal leaves with chlorosis and necrosis) and ability to avoid direct light (medial leaves with a more vertical position followed by lower temperatures and higher CO2 fixation capability and water use efficiency during the hottest hours of the day).&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Conclusion&lt;/strong&gt;: In the Sangiovese leaves developed under drought, the protective effect of increasing leaf angle with a more vertical position and the energy costs saved by reducing photosynthetic pigments formation, changing leaf optical properties, diminishing xylem and shoot growth and leaf area development and limiting down-regulation of photoassimilation help maintain high physiological efficiency in all the distal leaves. Significance and impact of study: The results indicate that cultivar Sangiovese exhibit high adaptation to dry conditions.&lt;/p&gt;

Penaeus vannamei isotrypsins: purification and characterization

Three isotrypsins from digestive gland of Penaeus vannamei were purified and characterized by molecular, biochemical and kinetic parameters. Purified isotrypsins A, B, and C are glycoproteins with molecular masses between 30.2 and 32.9 kDa, and, therefore similar to other trypsins. The isoelectric points are anionic and different among the three isotrypsins: pH 3.5 for isotrypsin A, pH 3.0 for isotrypsin B, and pH 4.5 for isotrypsin C. Differences in the NH 2-terminal amino acid sequences allowed us to define three different protein entities that match isotrypsins previously deduced by cDNA. Isoform C has higher physiological efficiency and specific activity, lower K m , and requires higher concentrations of Ca +2 to reach the same activity as the other two isotrypsins.

Nutrient Accumulation and Utilization in Rice Under Film‐Mulched and Flooded Cultivation

In recent years, plastic film mulched cultivation has been widely used in China as a strategy to reduce irrigation water consumption and increase water use efficiency (WUE). Experiments were conducted to study nitrogen (N), phosphorus (P), and potassium (K) accumulation and utilization in flooded rice comparing plastic film mulched (PFM) and conventionally flooded cultivation (CFC) in two successive years. In comparison with the plants under CFC, the plants under PFM had significantly higher N concentration at booting stage and lower K and P concentrations at heading and maturity stages and N concentrations after booting stage. More N accumulation was found in PMC‐treated plants than in CFC‐treated plants before booting, while thereafter CFC showed a significant increase in nutrient accumulation. N, P, and K accumulation ratios were significantly larger for PFM than for CFC at early stage (before booting), but the trend was just opposite after booting. The PFM‐treated plants substantially showed smaller nutrient accumulation rate through the whole growing process relative to the CFC‐treated plants. Although PFM‐treated plants had significantly higher physiological efficiency (PE) of all three nutrients than the CFC‐treated plants, its fertilizer recovery efficiency (RE) and agronomic nutrient utilization efficiency (AE) was markedly lower due to lower biomass and grain yield. In addition, the PFM‐treated plants had lower P/N and K/N in terms of nutrient accumulation, suggesting the importance to improve the P and K availability in rice film‐mulched cultivation.

Intraspecific Differences in Physiological Efficiency of Juvenile Atlantic Halibut Hippoglossus hippoglossus L.

AbstractWe compared growth efficiency, feeding consumption, metabolism, excretion, and energy allocation in populations of juvenile Atlantic halibut from Norway, Iceland, and Canada reared at low (8 C), medium (12 C, 15 C) and high (18 C) experimental temperatures. Our findings show that protein utilization and energy allocation in juvenile Atlantic halibut varies among different populations, as the Norwegian population displayed the highest protein efficiency ratio, protein production value, and energy conversion efficiency compared to the Canadian population, while the Icelandic population showed overall intermediate growth performance. The results do not conform to a simple thermal adaptation model but might represent an example of: 1) local adaptation of fish populations; or 2) countergradient variation where shorter growing season at higher latitudes is compensated with higher physiological efficiency. These findings have implications for halibut culture, particularly in selection work focusing on growth performance.

Discrimination in Performance Assessments against the Aged

Five independent experiments were conducted with a total of 395 Ss (aged 7 to 93 yr.) performing six diversified tasks to study the phenomena of increase and decrease in performance and physiological and behavioral changes with ageing. Results with the greatest impact on occupational productivity are: human body's physiological efficiency is the highest at a freely chosen pace for the age bracket 20 to 45 yr., while paced performance yields the highest physiological efficiency for the age bracket 45 to 65 yr.; different predictive validity models exist for different age categories, as the younger industrial operators (15 to 35 yr.) have higher test scores than the older age group (36 to 58 yr.) for an equivalent level of production performance. Both manipulative skills and personality attributes are affected by ageing.