Irradiation and storage effects on some properties of potato starch and use of thermoluminescence for identification of irradiated tubers

The effect on properties of starch isolated from Ajax and Diamant potatoes freshly harvested and irradiated immediately after harvest and after two weeks with 0.05, 0.10, 0.15, and 0.20 kGy were reported. Changes due to postirradiation storage up to six months at two different conditions (5 C, 90±2% RH and 20 C, 79±5% RH) were also studied. Swelling power (SP) slightly decreased or remained unchanged with different irradiation dose, but the effect of timing of irradiation after harvest was significant. Doses of 0.2 and 0.15 kGy significantly (p≤0.05) increased solubility, particularly at 90 C solubility temperature compared to lower doses. Decrease in viscosity with increasing dose immediately after irradiation was observed in both varieties but was more pronounced in Diamant. However, changes were dependent on variety, irradiation dose, timing of irradiation, and postirradiation storage conditions. Viscoamylograph test showed that 0.2 kGy significantly (p≤0.05) increased transmission temperature (TT) and temperature at maximum viscosity (TMV), but decreased the maximum viscosity immidiately after irradiation. The same trend was established during the post-irradiation storage time, particularly in Ajax starch, regardless of timing of irradiation or storage conditions. Thermoluminescence (TL) glow curves exhibited qualitative differences between irradiated and unirradiated tubers during the entire storage period, but dose estimation could not be determined.     

Suppressive ability of selected fodder plants on the growth of Parthenium hysterophorus

Parthenium hysterophorus is an invasive weed in Australian rangelands. It displaces valuable fodder plants and causes significant production losses within the cattle industry. Glasshouse screening trials were used to test 20 selected fodder species (test species) for their suppressive ability against P. hysterophorus growth. The trials used two planting densities (four or six plants per pot) and five planting frequencies. Each density by planting frequency was replicated three times. The dry shoot biomass of the test species was used to calculate a suppression index, in order to rank the relative suppressive abilities of the test plants. Setaria incrassata, Panicum maxicum and Cenchrus ciliaris were ranked as strongly suppressive, while Astrebla squarrosa, Bothriochloa pertusa, Themeda triandra, Astrebla elymoides, Bothriochloa decipens, Eulalia aurea and Lablab purpureus were moderately suppressive. The other test species had only poor suppressive abilities. A second glasshouse trial assessed the growth characteristics of the test plants at 13, 27 or 40 days after transplantation (DAT). Test species that strongly suppressed the growth of Parthenium hysterophorus had several attributes that included the ability to attain a greater height, the rapid production of tillers or a branched canopy and an extensive leaf area and root system; these growth attributes were present as early as 13 DAT. The present glasshouse screening approach identified several fodder species for further testing in field trials, and because the attributes that allow the test species to suppress Parthenium hysterophorus are present at the earliest stages of the plant’s life cycle, a rapid screening method is proposed that assesses these attributes at 27 DAT.     

Uncover the salt tolerance potential of accessions based on photosynthetic attributes and interaction plot in tomato (Solanum lycopersicum)

Soil salinity, being world's gravest and increasing environmental threat, limits the growth and development in nearly all crop plants. The experiment was laid out to investigate the tomato local and exotic germplasm for morpho‐physiological and photosynthetic attributes under salinity stress (0 (control), 8 and 12 dS m^?1). The phenotype data for morpho‐physiological traits were collected; meanwhile, photosynthetic pigments were analysed also at seedling stage. Analysis of variance, interaction plot, PCV and GCV revealed significantly greater diversity among all accessions for subjecting attributes. Strikingly, principle component analysis (PCA) biplot and cluster heatmap exposed potentially salt tolerant accessions (NAQEEB, BL1076, PBLA1401, 017859, TINY TIM, BL1174, BL1078, PBLA1932, TOMMY TOE, PAKIT and CLN2413) under the highest level of salinity for β‐carotene, lycopene contents, chlorophyll b, carotenoids, pheophytin (b) and total pheophytin. The overall performance of the above‐mentioned accessions was found significant and exhibits tolerant attitude under high salt levels. We suggest that these tolerant accessions might facilitate as a potential source for further breeding programme to improve the agronomically important traits by exploiting both conventional as well as molecular breeding efforts.     

High Sodium in Irrigation Water Caused B Toxicity at Low Soil Solution and Shoot B Concentration in Maize (Zea mays L.)

Sodium (Na) and calcium (Ca) in brackish water differentially affects boron (B) nutrition of plants grown on calcareous and salt-affected soils. A glasshouse experiment was conducted to evaluate the effect of brackish irrigation water with different sodium adsorption ratio (SAR_iw) [distilled-water control, 8, and 16 (mmol_c L^?1)^1/2] on B nutrition of maize. Plants were grown for 40 days with 5 levels of B (0, 1.29, 2.30, 3.22, and 4.46 mg kg^?1 soil). Boron application significantly improved plant growth at lower rates. High B rates and application of high SAR_iw decreased plant growth independently, and the reduction in growth was further aggravated due to combined effect of both B and high SAR_iw. Decreased growth was attributed mainly to increased shoot B and Na concentration, while decreased Ca concentration. These ionic changes also altered internal and external B requirements. Yield decrease was observed at lower B concentration in soil solution B and plants shoot grown with high SAR_iw than in plants grown with distilled water and low B application rates.     

Effects of varying dietary protein levels on growth, reproductive performance, body and egg composition of rohu, Labeo rohita (Hamilton)

A 360‐day feeding trial was conducted to observe the influence of varying levels of dietary protein on growth, reproductive performance, body and egg composition of rohu, Labeo rohita. Twenty fish (40.4 ± 0.24 cm; 852 ± 4.9 g), stocked in outdoor concrete tanks (200 m²), in duplicate, were fed diets with varying levels (200, 250, 300, 350 and 400 g kg^?1) of crude protein exchanged with carbohydrate to apparent satiation, twice daily, at 09:00 and 17:00 h. Higher (P < 0.05) weight increment was discernible in fish fed dietary protein ≥300 g kg^?1. Gonadosomatic index was comparable (P > 0.05) among fish of different dietary groups except those fed 200 g kg^?1 protein diet which produced least values. Egg diameter remained unaffected (P > 0.05) by variations in levels of dietary protein. Relative fecundity was maximum (P < 0.05) in fish fed 250 and 300 g kg^?1 protein diets. With the exception of fish fed 200 g kg^?1 protein diet, fertilizability (%) remained unaffected (P > 0.05) by variations in dietary protein level. Hatchability (%) followed the trend of variations almost similar to that of fertilizability. Proximate composition of muscle and eggs varied significantly (P < 0.05) with dietary protein levels. For broodstock L. rohita, a dietary protein level of 250 g kg^?1 was found optimum with regard to its reproductive performance, egg quality and composition.     

褐煤腐殖酸对不同土壤上小麦生长的影响

Humic acid(HA),a fairly stable product of decomposed organic matter that consequently accumulates in ecological systems,enhances plant growth by chelating unavailable nutrients and buffering pH.We examined the effect of HA derived from lignite on growth and macronutrient uptake of wheat(Triticum aestivum L.) grown in earthen pots under greenhouse conditions.The soils used in the pot experiment were a calcareous Haplustalf and a non-calcareous Haplustalf collected from Raisalpur and Guliana,respectively,in Punjab Province,Pakistan.The experiment consisted of four treatments with HA levels of 0(control without HA),30,60,and 90 mg kg -1 soil designated as HA 0,HA 1,HA 2,and HA 3,respectively.In the treatment without HA(HA 0),nitrogen(N),phosphorus(P),and potassium(K) were applied at 200,100,and 125 mg kg -1 soil,respectively.Significant differences among HA levels were recorded for wheat growth(plant height and shoot weight) and N uptake.On an average of both soils,the largest increases in plant height and shoot fresh and dry weights were found with HA 2(60 mg kg -1 soil),being 10%,25%,and 18%,respectively,as compared to the control without HA(HA 0).Both soils responded positively towards HA application.The wheat growth and N uptake in the non-calcareous soil were higher than those of the calcareous soil.The HA application significantly improved K concentration of the non-calcareous soil and P and NO 3-N of the calcareous soil.The highest rate of HA(90 mg kg -1 soil) had a negative effect on growth and nutrient uptake of wheat as well as nutrient accumulation in soil,whereas the medium dose of HA(60 mg kg -1 soil) was more efficient in promoting wheat growth.     

Spirulina inclusion levels in a broiler ration: evaluation of growth performance,gut integrity,and immunity

Tropical Animal Health and Production - Spirulina has been used as a food source from many years for human and animals because of its superior profile of nutrition. Spirulina (SPA) having antiviral...     

Complementary effect of zoo compost with mineral nitrogen fertilisation increases wheat yield and nutrition in a low-nutrient soil

Excess nitrogen(N) fertiliser use in agriculture is associated with water pollution and greenhouse gas emissions.While practices and programs to reduce N fertiliser application continue to be developed,inefficient fertiliser use persists.Practices that reduce mineral N fertiliser application are needed in a sustainable agricultural ecosystem to control leaching and gaseous losses for environmental management.This study evaluated whether fully or partially replacing mineral N fertiliser with zoo compost(Perth Zoo) could be a good mitigation strategy to reduce mineral N fertiliser application without affecting wheat yield and nutrition.To achieve this,a glasshouse experiment was conducted to assess the complementary effect of zoo compost and mineral N fertiliser on wheat yield and nutrition in a sandy soil of southwestern Australia.Additionally,a chlorophyll meter was used to determine whether there was a correlation between chlorophyll content and soil mineral N content,grain N uptake,and grain protein content at the tillering(42 d after sowing(DAS)) and heading(63 DAS) growth stages.The standard practice for N application for this soil type in this area,100 kg ha^-1,was used with a soil bulk density of 1.3 g cm^-3 to calculate the amount of mineral N(urea,46% N) and Perth Zoo compost(ZC)(0.69% N) for each treatment.Treatments comprised a control(no nutrients added,T1),mineral N only(100 kg N ha^-1,T2),ZC only(100 kg N ha^-1,T7),and combinations of mineral N and ZC at different rates(mineral N at 100 kg N ha^-1+ ZC at 25 kg N ha^-1(T3),mineral N at 75 kg N ha^-1+ ZC at 25 kg N ha^-1(T4),mineral N at 75 kg N ha^-1+ ZC at 50 kg N ha^-1(T5),and mineral N at 50 kg N ha^-1+ ZC at 50 kg N ha^-1(T6)).The T6 treatment significantly increased grain yield(by 26%) relative to the T2 treatment.However,the T7 treatment did not affect grain yield when compared to the T2 treatment.All treatments with mineral N and ZC in combination significantly improved the 1 000-grain weight compared to the T2 treatment.Chlorophyll content was better correlated with soil mineral N content(r = 0.61),grain N uptake(r = 0.62),and grain protein content(r = 0.80) at heading(63 DAS) than at tillering(42 DAS).While ZC alone could not serve as an alternative to mineral N fertiliser,its complementary use could reduce the mineral N fertiliser requirement by up to 50% for wheat without compromising grain yield,which needs to be verified in the field.Chlorophyll content could be used to predict soil mineral N at the heading stage,and further studies are warranted to verify its accuracy in the field.Overall,the application of ZC as part of integrated nutrient management improved crop yield with reduced N fertiliser application.     

An assessment of various pools of organic phosphorus distributed in soil aggregates as affected by long-term P fertilization regimes

The phosphorus (P) forms in long-term fertilization determine the fate and transport of P in soil. However, the fate of various pools of organic P of added P in the long-term measured with sequential chemical fractionation is not well-understood. Four soil physical aggregates (>250, 125–250, 63–125 and <63 μm) from 0- to 20-cm depth after 35 years of long-term fertilization treatments including control (CK), nitrogen and phosphorus fertilizer (NP) and NP combined with farmyard manure (NPM) under continuous winter wheat were separated using settling tube apparatus. Results showed that the application of long-term P fertilization had no apparent effects on promoting the mass proportion of soil aggregates except for >250 μm, where the NP and NPM treatments significantly increased the mass proportion by 60% and 70% over CK, respectively. Compared with CK, P fertilizer (NP and NPM) treatments significantly increased organic P (Po) contents in each size aggregate. In particular, mean labile Po increased by 35% and 246%, moderately labile Po by 125% and 161%, nonlabile Po by 105% and 170% and total Po (TPo) by 101% and 178%, respectively, under NP and NPM treatments, respectively. There was a significant correlation between soil organic carbon (SOC) and Po fractions. SOC was exponentially positively correlated with labile Po but linearly positively correlated with moderately labile Po, nonlabile Po and TPo fractions among soil aggregates. A reduced C:Po ratio (<100) in soil aggregates among treatment indicates a large amount of available P accumulated in soils, and soil P loss risk in the study site is still high. Our results show that the Po pool measured by sequential chemical fractionation may represent an important, yet often overlooked, source of P in agriculture ecosystems. According to the result, long-term mineral P fertilizer combined with organic amendments better sustains soil structural stability in large aggregates, contributing more Po availability in the moderately labile P followed by labile P in soil aggregates.