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41.
A local isolate of Metarhizium anisopliae (Hypocreales: Clavicipitaceae), Bacillus thuringiensis subsp. kurstaki and chlorantraniliprole were assessed against six field populations of tomato fruitworm Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) in a series of laboratory bioassays. Two dose rates of B. thuringiensis (0.5, 1 μg g?1), one of both M. anisopliae (1.3?×?106 conidia ml?1) and chlorantraniliprole (0.01 ppm) were applied alone and in combination with each other against 2nd, 3rd, 4th and 5th larval instars. The mortality was observed every 24 h until pupation. The bioassays were carried out at 25°C and 75% r.h. The highest mortality was observed in Rawalpindi with the lowest pupation rate by applying the combined concentrations of B. thuringiensis and chlorantraniliprole. The lowest mortality was observed in population from Gujranwala among all the tested populations. The antagonistic interaction was noted where the high dose rate of B. thuringiensis was combined with M. anisopliae; however, the remaining interactions enhanced the mortality and reduced the percent pupation. The overall results demonstrated that all the treatments gave significant control of the larval instars of H. armigera. The population from Gujranwala proved least susceptible whereas the one from Rawalpindi was highly susceptible.  相似文献   
42.
Conservation tillage may improve yield of cotton in addition to improvement in soil quality if practiced for longer period. However, the practice may not be productive in short-term particularly when severe weeds are infesting the crops such as Cynodon dactylon, Conyza canadensis, Tribulus terrestris, and Cyperus rotundus, etc. Recent studies indicate that conventional tillage (CT) is more productive than zero tillage (ZT)/reduced tillage (RT). Performance of cotton under three tillage systems, viz., ZT, RT and CT; and five herbicides, i.e., haloxyfop-R-methyl 10.8 EC (108 g a.i. ha-1), lactofen 24 EC (168 g a.i. ha-1), haloxyfop 10.8 EC + lactofen 24 EC, hand weeding, and weedy check were evaluated during 2010-2011 at Gomal University, D.I.Khan, Pakistan, to explore the best management option for effective weed control, enhanced yield and quality of cotton grown after wheat. The results revealed that hand weeding and Haloxyfop as post emergence alone or in combination with Lactofen reduced weed density to the minimum irrespective of the tillage systems. Excessive rainfall and cooler temperature limited cotton growth and yield in 2010. The adverse weather conditions had more adverse effect on boll weight under ZT and RT than CT. Haloxyfop + lactofen produced higher seed cotton yield in RT than ZT, however, it could not exceed CT. Broad-spectrum herbicides×CT produced the highest number of bolls/plant, boll weight and seed cotton yield. Fiber quality and net returns were also the highest in broad-spectrum herbicides×CT. In conclusion, broad-spectrum herbicides under CT were more productive in wheat based cropping system on silty clay soil of D.I.Khan.  相似文献   
43.
A total of 17 microsatellite deoxyribonucleic acid loci used routinely for horse parentage control were used to evaluate genetic diversity among normal Arabian horses and severe combined immunodeficiency (SCID) carrier Arabian horses (ArS) and normal Arab-Barb horses and SCID carrier Arab-Barb horses (ArbeS). On the basis of the genotype of 186 horses, mean allelic diversity was estimated as 6.82, 5.53, and 6.7059 in normal Arabian horses, ArS, and for both groups of Arab-Barb horses, respectively. Five specific alleles were observed in ArS and ArbeS, with one common with ArS at HMS6, whereas five alleles common between ArS and ArbeS had a high frequency. Expected and observed heterozygosity showed great heterogeneity in the population studied and were similar or higher when compared with other studies on Arabian horses. Coefficient of gene differentiation Gst of Nei associated with Nei’s genetic distance and multivariate correspondence analysis indicated a possible differentiation between the studied populations when analyzed separately according to breed. Probability of assignment of a horse to a specific group was assessed using a full and partial Bayesian approach. In all, 80.6% of Arab horses and 78.2% of Arab-Barb horses were assigned properly with a partial Bayesian test, which provided better results than the full one. These findings will be useful for identification of SCID carrier horses by using the microsatellite deoxyribonucleic acid loci used routinely for horse parentage control in our laboratory.  相似文献   
44.
Amino sugars are increasingly used as indicators for the accumulation of microbial residues in soil and plant material. A reverse-phase high-performance liquid chromatography method was improved for the simultaneous determination of muramic acid, mannosamine, glucosamine and galactosamine in soil and plant hydrolysates via ortho-phthaldialdehyde (OPA) pre-column derivatisation and fluorescence detection. The retention time was reduced, and the separation of muramic acid and mannosamine was optimised by modifying the mobile phase. The effects of excitation wavelength, OPA reaction time, tetrahydrofuran concentration and pH value of the mobile phase on the amino sugar separation were tested. Quantification limits were in the range of 0.13 to 0.90 μg ml−1. No interferences exist from amino acids or other primary amines, occurring in soil and plant hydrolysates.  相似文献   
45.
The objectives of the study were to evaluate haemodynamic changes and their relationships among ipsilateral (IPS) and contralateral (CONT) uterine arteries (UA) during different stages of pregnancy in Bos indicus cows. Multiparous pregnant cows (n = 40) having a gestation length 30.47 ± 0.54 (mean ± SD) days were randomly enrolled and subjected to Doppler ultrasonography sequentially at 1st, 2nd, 4th, 6th and 8th months of gestation. Blood flow indices including diameter of UA (mm), blood flow volume (BFVo, ml/min), blood flow velocity (BFVe, cm/s), time-averaged maximum velocity (TAMV, cm/s), pulsatility index (PI) and resistance index (RI) were recorded. Data were analysed with mixed models using the PROC MIXED procedures, and Pearson correlation coefficients were calculated using the PROC CORR statement in SAS. The final statistical models included the fixed effects of side of UA, gestation month and the interaction between side of UA and gestation month. Results revealed that the mean diameter of the UA (12.13 ± 0.22 vs. 10.09 ± 0.22), BFVo (1236.33 ± 0.55 vs. 770.41 ± 0.55), BFVe (17.18 ± 0.42 vs. 15.58 ± 0.42) and TAMV (17.11 ± 0.44 vs. 15.77 ± 0.44) was higher (p < .05) in IPS as compared to CONT side of the UA in cows. However, PI and RI did not differ between IPS and CON arteries of uterus in cows. A very high and positive correlation (r = .89; p < .05) existed between the diameter of UA and BFVo starting from 1st to 8th months of gestation in IPS as well as CONT sides of UA. Moreover, TAMV was highly and positively correlated (r = .91; p < .05) with BFVe throughout the gestation. In conclusion, these haemodynamic changes in the UA could be used as a valuable validity tool to differentiate the compromised pregnancy in Bos indicus cows.  相似文献   
46.
Tropical Animal Health and Production - This study examined the analysis of personal and production performance of broiler farming in 10 cities of central Punjab (Lahore, Sheikhupura, Kasur, Okara,...  相似文献   
47.
Gesunde Pflanzen - Biochar (BC) is known to enhance plant growth and may activate plant resistance to various soil borne pathogens. In this experiment, the rice husk (RH) BC was combined with...  相似文献   
48.

Two independent field experiments (2017 and 2019) were conducted to evaluate the effects of plant growth promoting rhizobacteria (PGPR), arbuscular mycorrhizal fungi (AMF; AMF1: Rhizophagus irregularis strain and AMF2: AMF consortium) and compost (Comp) in comparison to chemical NPK fertilizers on growth and yield of lettuce plants and soil properties. The biofertilizers-biostimulants were applied alone or in combinations and increased significantly the lettuce dry weight (DW), number of leaves, and yield compared to the control. In the first experiment, the highest plant DW was obtained by NPK, PGPR?+?AMF2?+?Comp and PGPR treatments recording an increase of 109, 109, and 95%, respectively, compared to the control plants. In the second experiment the highest plant DW was obtained by the NPK (77%), followed by Comp and PGPR?+?AMF1?+?Comp treatments increasing the plant DW by 52 and 51%, respectively, compared to the control. Concerning to lettuce yield, in the first experiment, the highest yields were obtained by NPK, PGPR?+?AMF2, PGPR?+?AMF1?+?Comp, PGPR, AMF2?+?Comp, AMF1?+?Comp and AMF2 treatments recording an enhancement of 68, 64, 63, 58, 57, 57, and 55%, respectively. In the second experiment, the application of NPK based fertilizers resulted in the highest yield (77%), followed by PGPR?+?AMF1?+?Comp, PGPR?+?AMF2?+?Comp, AMF1?+?Comp, and AMF2?+?Comp treatments, increasing the yield by 61, 61, 54, and 55%, respectively, compared to the control. Concerning the soil organic matter (OM), the applied treatments had significantly increased the amount of the OM compared to the control. The highest amounts of OM were obtained by the PGPR?+?AMF2?+?Comp treatment in the first experiment and the PGPR?+?AMF1?+?Comp treatment in the second experiment. The available phosphorus (P) was significantly increased by the application of all treatments. The highest records were obtained by the application of Comp, PGPR?+?AMF1 and PGPR?+?AMF1?+?Comp treatment after the first experiment. In the second experiment, the highest amount of P was obtained by PGPR?+?AMF2?+?Comp treatment. Application of biofertilizers-biostimulants in combination proved to be beneficial for the improvement of the tested culture yield.

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49.

Salinity is a crucial problem which has affected crop productivity globally. Ascorbic acid is considered helpful against abiotic stresses due to its powerful antioxidant potential. In the pot experiment, salinity stress (0, 35, 70, and 105?mM) was applied to sweet peppers in split doses after 20 days of transplantation. To mitigate the adverse effects of salinity, ascorbic acid (0, 0.40, 0.80, and 1.20?mM) was applied as foliar spray after a 6-day interval during vegetative growth. Sweet pepper plants sprayed with distilled water (control) recorded maximum plant height (cm), leaf area (cm2), number of branches, stem diameter (mm), number of fruit plant?1, fruit diameter (cm), yield plant?1 (g), and chlorophyll content (mg 100?g?1), while the maximum polyphenol oxidase (PPO) activity (unit mg protein?1 min?1) and ascorbate peroxidase (APX) activity (unit mg protein?1 min?1) were recorded in plants treated with 70?mM NaCl application. Salinity stress beyond 70?mM significantly reduced all the studied parameters. An ascorbic acid concentration of 1.20?mM significantly mitigated the negative effects of salt stress and recorded maximum plant height (cm), number of leaves plant?1, leaf area (cm2), number of branches plant?1, stem diameter (mm), number of fruit plant?1, fruit diameter (cm), yield plant?1 (g), chlorophyll content (mg 100?g?1), PPO activity (unit mg protein?1 min?1), and APX activity (unit mg protein?1 min?1). Hence, a 1.20?mM concentration of foliar ascorbic acid could be used in saline conditions up to 70?mM of sodium chloride (NaCl) for better growth, productivity, and enzymatic activity of sweet peppers.

  相似文献   
50.
Precision Agriculture - Recently, agriculture has gained much attention regarding automation by artificial intelligence techniques and robotic systems. Particularly, with the advancements in...  相似文献   
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