Metals toxicity and its bioaccumulation in purslane seedlings grown in controlled environment

We aimed to find the toxicological impacts of Cd, Pb and Zn in single dozes and in combinations on Purslane (Portulaca oleracea) seedling. The Pursolane seedlings? grown in pots in a green house were treated with different soil treatments spiked (mg/kg) with Pb (300, 400 and 500), Cd (0.5, 1 and 1.5), and Zn (250, 500, 700) alone and then in specified combinations/concentrations i.e., Cd/Pb (0.5/300, 1/400, 1.5/500), Cd/Zn (0.5/250, 1/500, 1.5/700) and Pb/Zn (300/250, 400/500, 500/ 700). The results indicated that increasing concentrations of the studied HMs in seedlings tissues significantly (p P. oleracea seedling, compared to Pb and Zn. Roots of P. oleracea seedlings were more sensitive to the studied HMs in comparison with shoot. The uptake patterns showed antagonistic impacts on each other and were reflected in response to growth parameters. The combine toxicities of Cd, Pb and Zn (Cd/Pb, Cd/Zn and Pb/Zn) were more than the toxicity due to single dose of each element but less than their additive sums.

Effects of different planting systems on yield of potato crop in Kaghan Valley: A mountainous region of Pakistan

Conversion of potato from conventional methods to wide bed planting systems may increase water and nitrogen use efficiency in commercial potato production system by reducing the amount of irrigation water and water applied nitrogen fertilizer bypassing the potato root zone. Potato (Solanum tuberosum L) cv. Desiree was tested against different planting system for yield and yield components at Kaghan, a high mountainous Himalayan region ofPakistan. The experiment was carried out at Himalayan Agricultural Research Station (HARS), Kaghan during the summer season of 2005. The results showed that maximum tuber growth (88.7%), number of stems per plant (3.5), plant expansion (45.5 cm), average number of tubers per plant (10.1) and yield per hectare (12.4 t/ha) were significantly different and higher when potatoes were planted on wide bed and covered with soil from one side. Tallest plants (53.4 cm) were observed when potatoes were sown on the ridges. Maximum number of green potatoes (12.5) and injured potatoes (5.3%) were observed when the tubers were planted following local farmers’ method. Keeping in view the soil type, land slopping, we recommend sowing potatoes on relatively plain wide beds and covering it with soil from one side, for potato cultivation in the area.

Contribution of soil and foliar fertilization of nitrogen and sulfur on physiological and quality assessment of wheat (<i>Triticum aestivum</i>L.)

Nitrogen and sulfur supplies have a strong influence on the physical characteristics of crop as well as on the quality and quantity of wheat storage proteins, which play an important role in bread-making process. In order to evaluate the contribution of soil and foliar fertilization of nitrogen and sulfur on physiological and quality assessment of wheat, a field trail was carried out having randomized complete block design with four replications and eight different treatments of nitrogen and sulfur combinations were allotted to plots at different growth stages. Results indicated that highest protein content (12.82%), maximum moisture content (10.9%), maximum crop growth rate and maximum absolute growth rate were recorded when the wheat crop was fertilized with T8 [Nitrogen @ 60 kg·ha-1 at sowing + 40 kg·ha-1 at tillering + 10 kg·ha-1 at anthesis (spray) + 10 kg·ha-1 after anthesis (spray)] + [Sulfur @ 15 kg·ha-1 at sowing + 10 kg·ha-1 at anthesis (spray) + 5 kg·ha-1 after anthesis (spray)], while control practice resulted low moisture content, low protein, minimum crop growth rate and low absolute growth rate. Among physiological components of wheat cultivars, leaf area index was enhanced when fertilization was done with T5 (Sulfur @ 15 kg·ha-1 at sowing + 10 kg·ha-1 at anthesis + 5 kg·ha-1 after anthesis). In all the recorded observations,concerning experiment wheat cultivar Pirsabaq2005 showed appreciable response as compared with other variety (Khyber-87). Thus it is possible to obtain maximum physiological traits as well as bread-making quality of wheat through soil and foliar application of nitrogen and sulfur.

Hydro-meteorological characteristics of Chitral River basin at the peak of the Hindukush range

This paper presents the impact of mean maximum temperature on Chitral river basin situated at Chitral district and high altitude (>6000 m) peaks of the Hindukush range under changing climate in Pakistan. The analysis of Chitral River as one of the tributary of Kabul River—the second largest river of Pakistan—revealed that change in temperature has a profound influence on the snow/glacial melt in comparison to the mean monthly rainfall. This is because the studied river is faded by the snow and glacial melt and receives a lot of snowfall from winter (DecFeb) to pre-monsoon (April-May). In monsoon period (Jul-Sep), 30% of the time the discharge rate remains above the mean while 60% of the time the discharge is less than the mean in the pre-monsoon (April-May) period. It means that 10% of the time the discharge is in reach of 300% to 900% of the mean flow, showing a rise in water yield and river discharge rate due to increase in mean monthly maximum temperature. Due to this significant increase (p < 0.05), the glaciers start melting faster and disappear in early summer, hence, reducing their residency period to convert into ice. This shows the signals of changing climate transfer into hydrological changes in Pakistan. Our findings are important for agriculture, hydropower and water management sectors for future planning especially in dry season for sustainable food security and for operation of ydrological installations in the country.

An Insight of Ecosystem Capitals and Services of the Kaghan Valley: The Himalayan Region of Pakistan

The Kaghan Valley is in the territorial jurisdiction of Mansehera District, named after a tiny village Kaghan, at the end of the valley. The valley culminates in the tree-clad high mountains and glaciers in the North-East with varying altitudes from 1 to 5 thousand meters above sea level. The region is relatively active geophysically, hydrologically and biologically diverse by virtue of the altitude and aspect-driven variability in energy and moisture. In such region a better understanding of changes in land resources, production of agronomic and horticultural crops, use of timber and non-timber products, and livestock structure/composition have important implications and understanding these changes along with the indigenous knowledge of mountain people which, is key to sustainable development of the Himalayan region. Our results showed that the main causes of lowest agriculture production in the area are poor crop management in context of the mountains, drought spells, low soil fertility, land fragmentation and tenancy status of the agricultural land. Off season vegetables cultivation on the sloppy land leads to sever soil erosion and soil land degradation of this mountain ecosystem. Overgrazing during the summer season is another problem as the pastures are visited both by the Afghan and local nomads without relating with carrying capacity of the alpine meadows. The overgrazed soil is usually subject to rainfalls and severe soil erosion. Any use of resources of such fragile rare high mountain ecosystem requires a great sense of responsibility but in this case the forest resources are being plundered and are used roughly. We recommend adequate use of agricultural inputs, specific crop management practices for mountain agriculture. Local social welfare organizations should work to create awareness about the sustainable use of natural resources. The government should resolve the ownership problem of land as common property keeping in mind the customary laws of the region to make sure the involvement of all stakeholders.