Muhammad Jamal Khan

Response of Maize to Different Levels of Sulfur

Abstract A field experiment was conducted to assess the effect of different levels of sulfur (S) on yield and yield components of maize crop grown on silt loam soils at the Agriculture Research Station Baffa, district Mansehra. The soil contained 1.17% organic matter, 10% CaCO3, and 39 mg SO4‐S kg−1. Sulfur was applied at 0, 20, 40, 60, 80, 100, and 120 kg ha−1 as gypsum along with 120 kg N, 90 kg P2O5, 60 kg K2O ha−1 replicated thrice in RCB design. Soil samples at silking and harvesting stage from each treatment plot along with leaf samples were collected for the determination of S. Yield and yield components of maize were significantly (p<0.05) enhanced with the application of S compared with control. Sulfur at 60 kg ha−1 produced highest yield of fresh matter, dry matter, stover, 1000‐grain and total grain, resulting in increases of 41, 55, 58, 5, and 43%, respectively. Application of S above 60 kg S ha−1 reduced yield and yield components, suggesting a classical yield response curve. The analysis of soil samples at silking and harvesting stage from each treatment plot revealed that soil SO4‐S concentration increased significantly by S application reaching the level of 108.4 and 99.7 mg kg−1, respectively, with 120 kg S ha−1. Sulfur concentration of leaves was significantly increased with the application of S compared with the control. Application of sulfur at 60 kg ha−1 produced leaf S concentrations of 0.46%, which is less than the critical level of 0.5%, whereas higher treatments increased S concentration ranging from 0.67 to 0.94%, which exceeded the value considered as high (0.5%) and excessive (0.8%). Elevated tissue sulfate concentrations induced by treatments greater than 60 kg ha−1 corroborate with the corresponding yield decreases of maize. Maize growers of the area may add S up to 60 kg ha−1 to obtain maximum yield.

Comparison of wheat yield under uniform and variable rates of fertilizer on spatially‐eroded land

Abstract Field studies were made to determine the yield and quality of wheat at different landscape positions managed with uniform vs. variable rates of nitrogen (N). A moderately‐eroded wheat farm near Thana (Swat) was divided into four parallel transects which were further divided into two strips each. On one strip, fertilizer was applied at a uniform rate of 120 kg N ha‐1, and along the other strip, three different rates of N (80, 110, and 125 kg N ha‐1) were applied to match the crop productivity patterns. A basal dose of 90 kg P2O5 and 60 kg K2O ha‐1 was applied to the whole field. Soil profiles were described for the three different zones, i.e., low, medium, and high productivity zones. Soil in Zone I was Pirsabak, moderately deep variant, and in Zones II and III, Badwan soil series. Although uniformly fertilized strip (120 kg N ha‐1) received 40 and 10 kg N ha1 more than Zone I and Zone II (variable management strategy), there were no significant differences in yield. The differences in three ferti...

Use of spatial patterns of soil properties and wheat yield in geostatistics for determination of fertilizer rates

Abstract Researchers traditionally conduct fertilizer experiments on small, replicated areas at university or governmental research centers. This approach has two problems: (1) extrapolation of the results to large cropped fields requires taking into account the impacts of spatial variability of soil properties on the optimum amount and type of fertilizer to apply and (2) farmers have limited access to the research work, particularly in developing countries, which limits the information transfer needed for farmers to adopt the recommended fertilizer techniques. With these problems in mind, field and laboratory investigations were conducted on a farmers field to study the spatial patterns of some soil properties and wheat yield using geostatistics for determination of fertilizer rates. The field was divided into four parallel transects, and soil samples were collected at 15‐m intervals along each transect. These soil samples were analyzed for different physical and chemical properties. A uniformity trial ...

Assessment of AquaCrop Model in Simulating Sugar Beet Canopy Cover, Biomass and Root Yield under Different Irrigation and Field Management Practices in Semi-Arid Regions of Pakistan

The AquaCrop model was analyzed for simulating sugar beet crop production under four irrigation regimes, three mulching conditions and three furrow irrigation systems in semi-arid region of Pakistan. Irrigation regimes were full irrigation (FI), 20% deficit irrigation (DI20), 40% deficit irrigation (DI40) and 60% deficit irrigation (DI60). The mulching practices were No-mulch (NM), black film mulch (BFM) and straw mulch (SM). The furrow irrigation systems were conventional ridge-furrow (CRF) system, medium raised-bed (MRB) system and wide raised-bed (WRB) system. The model was calibrated and validated using the independent data sets of full irrigation and deficit irrigation regimes collected during 2011–12 cropping season. The model performance was evaluated by using different statistical indicators such as Root Mean Square Error (RMSE), index of agreement (dindex), and Nash–Sutcliffe Efficiency (NSE). These indicators showed that the model fairly simulated sugar beet canopy cover for all treatments with 3.00 ≤ RMSE ≤ 16.89, 0.84 ≤ dindex ≤ 0.97, and 0.76 ≤ NSE ≤ 0.99. For biomass and root yield, the model performance was excellent under all full irrigation (FI) and mild deficit irrigation (DI20) treatments with RMSE ranged between 0.07 and 1.17, dindex between 0.48 and 0.84, and NSE between 0.42 and 0.86, respectively. However the low values of dindex (0.10 and 0.13) and NSE (−69.32 and −30.63) showed that the model overestimated both the biomass and root yield when 20% deficit irrigation was applied without mulch in WRB system. The model also over estimated the yield and biomass when 40% deficit irrigation was applied in CRF system. The highest overestimation (dindex: 0.10 to 0.11; NSE: −50.92 to −70.55) was observed when highest stress level (DI60) was applied in the presence of BFM in CRF system. Based on the model’s overall performance, the AquaCrop application is recommended for developing efficient farm water management strategies in the semi-arid regions.

Analysis of groundwater behaviour in a farmer controlled subsurface tile drainage system in Mardan, Pakistan

Extensive subsurface drainage system was installed in districtMardan in the North West Frontier Provinceof Pakistan in 1987 to control increasingwater logging and salinity problems due tocanal irrigation. Several recentlycompleted fields studies have indicatedthat subsurface drainage system hasenormously lowered watertable in certainareas due to extensive drainage network. Therefore, a study of controlled subsurfacedrainage technique was initiated in MardanScarp area to observe the temporal andspatial variations in water table depths ofthis specific case under various modes ofcanal irrigation and monsoon rains. Twoartificially drained areas, consisting of40 ha and 160 ha respectively, werecontrolled and selected for extensivemonitoring. A total of 98 observationswells (7.6 cm dia. and 4.1 m depth) wereinstalled in between lateral drains toobserve water table fluctuation. Theresults of this study are very interesting.Each of the two areas monitored in thestudy behaved differently. It was observedthat in one of the areas design water tabledepth at 1.1 m was maintained with properfunctioning of the controlled techniqueapplied to the subsurface drainage system. The results from this area showed that 25to 55% of the time throughout the yearachieved this objective whereas in thesecond area desired water table could notbe maintained and water table depth in thisarea remained between 2.0 to 2.7 m causingunnecessary water stress to plants. Alsoit was observed that watertable in theformer area is mostly controlled by thefunctional behavior of the irrigationcanal. In addition, the proper functioningof controlled techniques in subsurfacedrainage system supplemented veryefficiently to retain the groundwater levelto the optimal limits in dry season and tothe design ones in the others for timelyneeds of the crops. Also rainfalls havesignificant impact on the spatial andtemporal behaviors of water table depths inboth the areas during the monsoon season.

Effect of temperature on the synthesis of Centella asiatica flavonoids extract-mediated gold nanoparticles: UV-visible spectra analyses

Many plants have been reported for the nanosynthesis of metal nanoparticles by virtue of the reducing potential of their bioactive compounds. Centella asiatica (CA) is one of the widely used plants, as claimed by traditional system of medicine, to have its positive effects on a variety of ailments. However, no research evidence indicates the synthesis of CA flavonoids extract (CACrF)-mediated gold nanoparticles (GNPs). In the present study, the initial synthesis of gold nanoparticles (GNPs) mediated by Centella asiatica crude flavonoids extract (CACrF) has been discussed. The protocol involves a one-step, non-toxic and cost effective procedure based on green nanotechnology avoiding the use of any synthetic chemicals potentially harmful for environment and biomedical applications. The CACrF was reacted with gold chloride, trihydrate (HAuCl4.3H2O) for the synthesis of GNPs. The reaction was carried out at room temperatures. The formation of GNPs was visually observed by a change in the color of solution from pale yellow to ruby pink. UV-visible (UV-vis) spectrophotomteric analysis was performed to verify the synthesis of CACrF-mediated GNPs. As a function of time, the surface plasmon resonance (SPR) behavior of GNPs was evaluated to study the reaction kinetics and the UV-vis spectra were recorded after every 10 minutes up to 70 minutes. A single peak at 542 nm with absorbance of 0.475±0.039 indicated the synthesis of GNPs.Many plants have been reported for the nanosynthesis of metal nanoparticles by virtue of the reducing potential of their bioactive compounds. Centella asiatica (CA) is one of the widely used plants, as claimed by traditional system of medicine, to have its positive effects on a variety of ailments. However, no research evidence indicates the synthesis of CA flavonoids extract (CACrF)-mediated gold nanoparticles (GNPs). In the present study, the initial synthesis of gold nanoparticles (GNPs) mediated by Centella asiatica crude flavonoids extract (CACrF) has been discussed. The protocol involves a one-step, non-toxic and cost effective procedure based on green nanotechnology avoiding the use of any synthetic chemicals potentially harmful for environment and biomedical applications. The CACrF was reacted with gold chloride, trihydrate (HAuCl4.3H2O) for the synthesis of GNPs. The reaction was carried out at room temperatures. The formation of GNPs was visually observed by a change in the color of solution fro...

Impact of rhizobial inoculum and inorganic fertilizers on nutrients (NPK) availability and uptake in wheat crop

Abstract. Experiments were conducted to evaluate the effect of rhizobial inoculums and inorganic fertilizers on NP availability, soil microbial activity, wheat NPK concentration and uptake. These experiments were consisted of two factors, four inoculums (no, lentil, peas, and chickpeas) and two NPK doses (120:90:60 and 96:72:48 kg ha-1). Inoculums significantly increased plant total NPK concentration by 39, 57, and 37%, and their uptake by 66, 86, and 56%, respectively. Peas inoculum was most efficient in wheat NPK concentration and uptake. The interactive effect of inoculums and NPK demonstrated that peas and lentil inoculums with 20% less NPK had statistically better role than full NPK without inoculation. AB-DTPA extractible P and mineral N were progressively increased with incubation periods and exhibited significant differences between inoculated and uninoculated treatments during all incubation intervals for NP except at day 7 for N. Peas inoculum showed maximum mean net NP availability of 131.5 and 3.48 mg kg-1 over 56 d of incubation, respectively. Significantly higher cumulative CO2 of 1429 mg kg-1 with a net increase of 866 mg kg-1 was recorded for peas inoculums during 12 d of incubation interval. It is concluded that peas rhizobium could be used as a plant-growth-promoting rhizobacteria for wheat and other cereal crops.

ADVERSE EFFECTS OF SALINE TUBE WELLS WATER IRRIGATION ON SOIL AND CROP IN LACHI VALLEY OF DISTRICT KOHAT IN NWFP

Salinity has plagued crop production in irrigated regions of the world since the beginning of recorded history. It is particularly common in arid and semi-arid areas where evapo-transpiration exceeds annual precipitation and where irrigation is necessary to meet crop water needs, In the past, soil salinity was mainly associated with high ground water tables, which salts into the root zone through the capillary rise. But now-a-days, increasing exploitation of ground water for irrigation purposes has led to decline the ground water tables, and a threat of sodification and salinisation due to use of poor quality ground water. Same is the case in Lachi valley, where ground water is mined, and as a result salts are added to the root zone because a high proportion of irrigation water is derived from pumped ground water of poor quality. Farmers of the area are facing a situation in which they have to deal with salt volumes that are harmful for water uptake of crops. They are also facing the problems of sodicity, which has an adverse effect on the physical structure of the soil. From the analysis of soil samples, it was found that about 47% of the area is non-saline, 25% is saline, and 28% is sodic-saline. The area where once all type of crops was grown is now restricted to only a few crops due to land degradation caused by deteriorating water quality. Sugarcane, an important cash crop, has ceased to be grown while yields of maize and wheat have decreased drastically. The areas where tubewells water is normal, there the production is high for both the wheat and maize (3.5 and 6.5tons/ha respectively, but in the areas, where soil has been deteriorated due to application of saline tubewells water, there the yield of both the crops have been seriously affected (2.2 and zero tons/ha respectively).

EFFECT OF INITIAL MOISTURE STRESS LEVELS ON YIELD OF DIFFERENT WHEAT VARIETIES

Field experimentswere conducted to study the effect of initial moisture stress levels (65,80 and 95% of available moisture ) on three different wheat varieties ( Pak-81, Khyber-87, and Pirsabak-85 ) on silt loam soil at NWFP Agricultural University’s farm, Peshawar, Pakistan, during Rabi season of 1990-91. Consumptive use was worked out as a sum of soil moisture depletion between sampling, taking into consideration, the contribution of rainfall, amount of irrigation waterappliedanddeep percolation.Consumptive useof water for wheat was 365,355and327mm and average seasonal crop coefficients (KJ were 1.058, 1.028 and 0.973 at 65, 80 and 95% depletion of available soil moisture, respectively. The results obtained showed that there was not significant difference in yield and its componentsdue to various initial moisture stress levels maintained before first irrigation.However, the average yield at higher stress level (95% ) was 5 percent less than that of low stress level (65% ). The highest yield of 3450 kg/ha and maximum water use efficiency of 9.72 kg/ha/mm was obtained for variety Khyber-87 which was irrigated 24 days after sowing at 80% depletion of available soil moisture.