A Comparison of the Accuracy and Efficiency of Two Ionic Strength Adjustment Buffers in Measuring Potassium Using an Ion-Selective Electrode

It is recommended to use ionic strength adjustment buffers to increase reading accuracy while measuring potassium (K⁺) concentrations in aqueous solutions by using ion-selective electrodes (ISEs). Three laboratory leachate column studies were conducted to evaluate the efficiency of two buffers, 2.5 M sodium perchlorate (NaClO₄) and 2.5 M sodium chloride (NaCl), in measuring K⁺ concentrations in three media types (peat moss, Oxisols, and Mollisols soils). Three algae species, KCl, and KNO₃ were applied to provide 112 and 336 kg K/ha. Leachate samples were collected to a total of 16 weeks and measured using a K-ISE. The K⁺ data from the three trials showed a highly significant (r ~ 0.99) correlation between the two buffers. T-Test results showed highly significant (P < 0.01) differences between unbuffered and the two buffered solutions. However, there were no significant differences between the two buffered solutions, under the peat moss, Oxisols, and Mollisols soils. The results suggest that the least expensive buffer of 2.5 M NaCl is as accurate as NaClO₄ in such aqueous solutions.     

The effect of sawdust vermicompost extract on Syngonium podophyllum growth and nutrition

This study investigated the effects of four concentrations (0, 250, 500 and 1000?ppm) of a sawdust vermicompost extract on the growth and nutrition of Syngonium podophyllum. The extract, which was prepared using non-aerated extraction methods with a 1:10 (v: v) ratio of sawdust vermicompost to water, was sprayed three times on the Syngonium plants. Extract improved the mineral nutrient status of the plants. When the vermicompost extract was sprayed on the Syngonium plants, they showed significant growth. Germination tests did not show that vermicompost extracts would cause any potential damage to the plants. The spray containing the 1000?ppm extract had a great effect on Syngonium growth. Plants grown in pots and treated with the 1000?ppm vermicompost extract exhibited higher height, leaf area, chlorophyll, shoot fresh weight, and shoot dry weight than plants receiving control treatments. This study confirmed that sawdust vermicompost extract positively affects Syngonium plant growth.     

Effects of interaction of Meloidogyne incognita,Alternaria dauci and Rhizoctonia solani on the growth,chlorophyll, carotenoid and proline contents of carrot in three types of soil

Disease complex of carrot (Daucus carota L.) involving root knot nematode Meloidogyne incognita and two fungi Alternaria dauci and Rhizoctonia solani were studied in three soil types. More plant growth, chlorophyll, carotenoid and proline contents were found in carrot grown in fly ash mix soil than plants grown in sand mix soil and loamy soil. Inoculation of M. incognita, R. solani, and A. dauci reduced plant growth, chlorophyll and carotenoid but increased proline contents. Inoculation of M. incognita 20 days prior to a fungal pathogen caused a greater reduction in plant growth, chlorophyll and carotenoid than fungal pathogen was inoculated prior. Inoculation of A. dauci prior to R. solani or vice versa had a similar effect on plant growth, chlorophyll, and carotenoid. Nematode multiplication and galling was higher in plants grown in sand mix soil followed by loamy soil and fly ash mix soil. Both fungi had adverse effects on galling and nematode multiplication. Blight disease index caused by A. dauci was 3 and crown rot index by R. solani was also recorded 3. These disease indices were 5 when pathogens were inoculated in combinations.     

Heat stress and plant development: role of sulphur metabolites and management strategies

Temperature plays a crucial role in plants development whereas a sudden rise may cause severe consequences. Heat stress impairs plant growth, photosynthesis, pollen development and reproduction. The plant photosynthetic efficiency is mainly reduced by the over production of reactive oxygen species, denaturation of heat shock proteins and alteration in many enzymes activities. Unlike drought stress, plants have developed a very few mechanisms to encounter heat stress problem. Recently, the use of nutrients such as sulphur has emerged as one of the efficient methods to enhance plant tolerance against high temperature stress. The mechanistic understanding of sulphur-based strategies could be very helpful to sustain plant development and global food supplies in future hotter climates. The present review mainly focuses on (1) high temperature induced changes in plant functions, (2) possible roles of sulphur metabolites in heat stress tolerance and (3) possibilities of using sulphur as a management strategy. Moreover, the review consolidates the future research needs that must focus on (i) heat tolerant germplasm screening; (ii) sulphur dose optimisation, application method and crop growth stages response; (iii) finding of sulphur induced heat tolerance mechanisms and (iv) the use of omic approaches to discover sulphur metabolites role in heat stress tolerance.     

Dietary and non-dietary determinants of central adiposity among Tehrani women

OBJECTIVE: To determine the correlates of central adiposity. DESIGN: Population-based cross-sectional study. SUBJECTS: A total of 926 women (aged 40-60 years) from all districts of Tehran. METHODS: Demographic data were collected and anthropometric indices were measured according to standard protocols. Dietary intakes were assessed by means of a semi-quantitative food-frequency questionnaire. The suggested cut-off point for waist-to-hip ratio (WHR>or=0.84) for Tehrani people, adjusted for their age group, was used to determine central adiposity. Logistic regression analysis was used to determine the correlates of WHR, which were adjusted for age, taking medications and body mass index (BMI). The components of dietary intake were determined by factor analysis. Pearson correlation was used to determine the association between the dietary components and WHR. Analysis of covariance was employed to compare the mean values of WHR in different lifestyle groups, with adjustment for BMI and age. RESULTS: Mean WHR was 0.82 +/- 0.06. The possibility of being centrally obese was higher in women with light physical activity (odds ratio: 2.11; 95% confidence interval: 1.40-2.53), depressed women (1.36; 1.02-1.93), smokers (1.21; 1.02-1.56) and unemployed women (1.41; 1.13-1.72). Marriage (1.31; 1.10-1.82), menopause (1.22; 1.02-1.61), low vitamin C intake (2.31; 1.25-4.25) and low calcium intake (1.30; 1.07-3.78) were associated with central fat accumulation. Dairy consumption was inversely correlated with central fat accumulation (r = -0.2, P < 0.05). CONCLUSION: Central adiposity is associated with poor lifestyle factors including low physical activity, depression, smoking, low intake of vitamin C, low intake of calcium and dairy products and high fat consumption. Thus lifestyle modifications should be encouraged to achieve a healthier body shape.     

Foliar spraying of aqueous garlic bulb extract stimulates growth and antioxidant enzyme activity in eggplant(Solanum melongena L.)

Recently,botanical extracts are gaining popularity as biostimulants in vegetable production.In present study,the effect of aqueous garlic bulb extract(AGE)was studied on the growth and physiology of eggplant grown in plastic tunnel.AGE was foliage sprayed with various frequencies,i.e.,0,S1(once),S2(twice)and S3(three times)at two independent growth stages,pre-and post-transplant.The results showed that the treated plants exhibited stimulatory responses in growth and physiology in accord with the repetition of AGE spray and growth stages of the plants,respectively.A single foliage sprayed pre-transplant resulted in improved growth,i.e.,plant morphology and biomass,and enhanced antioxidants enzymes(superoxide dismutase,SOD;peroxidase,POD),photosynthesis and chlorophyll abundance observed at vegetative,first flowering and fruit setting stages,respectively.However,thrice application inhibited the plant growth and development and resulted in lipid peroxidation,i.e.,increased malondialdehyde(MDA)content.In addition,the post-transplant application also showed growth stimulation and interestingly,an overall positive influence was observed with respect to the AGE application and no significant increase in the MDA content indicated the post-transplant seedlings responded well.Our findings demonstrate that AGE can act as a biostimulant to enhance the eggplant growth in plastic tunnel production.     

Influence mechanism of climate change on paddy farming practices and irrigation water demand

Paddy and Water Environment - Technological and socioeconomic interventions accompanied by climate warming strongly dictate farming practices, lending a direct impact over future irrigation water...     

利用杨树人工林剩余物生产刨花板可行性研究

The composite board industry in Iran is obliged to use residues from forest operation as well as wood industry for competing with paper industry because of shortage of wood. In the present study we investigated the residues from poplar plantation used for particleboard production. Three kinds of wood materials, poplar branches, small diameter poplar wood (3–8 cm) and beech wood, were used in the experiment of particleboard production. The results demonstrated that the characteristic of particleboard made from poplar branches and small diameter wood is comparable to that made from mature beech wood. To avoid too much residual acid in the final board, the properties of boards produced with 1.5% hardener at 175°C press temperature are acceptable, although the properties of particleboard produced with 2% hardener were higher than were higher than that of the board produced with lower hardener (1% or 1.5%).. The MOR, MOE and IB of particleboard made from branches were measured as 14.57, 2015, and 1.32 MPa, respectively, while The MOR, MOE and IB of particleboard produced from small diameter poplar wood were 19.90, 2199, and 1.86 MPa, respectively. The thickness swelling of boards made from branches after 2 and 24 h immersion in water was 20.14% and 31.26%. The utilization of branches and very small diameter wood of poplar is recommended for the survival and developments of particleboard industry in Iran.     

Potential of Kochia prostrata and Perennial Grasses for Rangeland Restoration in Jordan

Six varieties of forage kochia (Kochia prostrata [L.] Schrad.), two Atriplex shrubs native to North America, and four drought-tolerant perennial grass varieties were seeded and evaluated under arid rangeland conditions in Jordan. Varieties were seeded in December 2007 and evaluated in 2008 and 2009 at two sites. Conditions were dry with Qurain receiving 110 mm and 73 mm and Tal Rimah receiving 58 mm and 43 mm of annual precipitation during the winters of 2007/2008 and 2008/2009, respectively. Plants were more abundant and taller (P < 0.001) at Qurain than Tal Rimah in 2008. Forage kochia frequency was 48% and 30% in 2008 at Qurain and Tal Rimah, respectively. However, no seeded plants were observed at Tal Rimah in 2009, suggesting that 58 mm and 43 mm of annual precipitation are insufficient to allow plants to persist over multiple years. At the wetter site, forage kochia abundance in 2009 was similar (P = 0.90) to that observed in 2008 and plant height increased (P < 0.001) from 2008 (14.4 cm ± 1.1 SE) to 2009 (38.4 cm ± 1.1 SE). Sahro-select and Otavny-select were the most abundant forage kochia varieties (P < 0.05), suggesting that these experimental lines could be more adapted to the environmental conditions of Jordan than the commercially available cultivar Immigrant. Frequency of perennial grass varieties declined (P < 0.001) at Qurain from 82% ± 4 SE to 39% ± 4 SE between 2008 and 2009, respectively. Among grasses, Siberian wheatgrass had better stands than crested wheatgrass, with Russian wildrye being intermediate. Based on this study, forage kochia appears to have great potential for establishing palatable perennial shrubs in arid rangeland conditions in Jordan if annual precipitation is at least 70 mm. Arid-adapted perennial grass varieties might also be useful in rangeland restoration if annual precipitation is over 100 mm.     

Enhancing the performance of transplanted coarse rice by seed priming

Raising the rice seedlings in the nursery and its transplantation into the flooded fields is principal method of rice cultivation in the world. Traditional nursery raising method in Pakistan is tedious and produces week seedlings, which reduces the final yield due to high mortality. The potential of seed priming to improve the nursery seedlings and thus the transplanted rice was evaluated in the present study. Seed priming tools employed during the investigation included traditional soaking (pre-germination), hydropriming for 48 h, osmohardening (KCl or CaCl₂) (ψs-1.25 MPa) for 24 h (1 cycle), ascorbate priming (with 10 ppm ascorbate) for 48 h or seed hardening for 24 h. Priming improved nursery seedling vigor and resulted in improved growth, yield and quality of transplanted rice. Osmohardening (KCl) consequently resulted in the best performance, followed by osmohardening (CaCl₂)_, hardening and ascorbate priming. Osmohardening (KCl) produced 4.28 t ha⁻¹ (vs. 3.51 t ha⁻¹ from untreated control) kernel yield, 10.27 t ha⁻¹ (vs. 9.34 t ha⁻¹ from untreated control) straw yield and 29.41% (vs. 27.31% from untreated control) harvest index. The improved yield was attributed to increase in number of fertile tillers.