Khawaja Shafique Ahmad

Ecotypic adaptations in Bermuda grass (Cynodon dactylon) for altitudinal stress tolerance

Abstract Three ecotypes [foot hill (700 m), mid hill (1571 m) and top hill (2804 m)] of a Bermuda grass Cynodon dactylon (L.) Pers. from Pir Chinasi Hill in Western Himalaya were evaluated for their degree of tolerance to altitudinal stress. Differential response of all ecotypes in terms of adequate structural modifications to different elevation levels was an evident to confirm the hypothesis that plants inhabiting different altitudes show variation in structure (internal modifications) and strategic (response) due to heterogeneity in environmental gradients. Soil at top hill site was more acidic and displayed significant increase in ionic content and total nitrogen. High elevation had severe impact on morphoanatomical and physiological attributes. A significant decline in shoot fresh weight and total leaf area was observed in top hill ecotype. With exception of Ca2+ and carotenoid, other ionic and chlorophyll content were significantly declined at high elevations. Anatomical alterations such as, increased leaf thickness, intensive sclerification around the vascular bundle and pith area, reduced metaxylem vessel area, high number of silica bodies, high pubescence (increased microhair and trichome density) were some of the promising anatomical adaptations in top hill ecotype which played an important role in high degree of tolerance of this grass to cope with altitudinal stresses. Increased leaf thickness might be a response to lower temperature that protects mesophyll cells and high density of trichomes may be involved in blocking transpiration water and internal heat. The pattern of constant variation suggests that differential response of these ecotypes is highly related to air temperature, pattern of rainfall, availability of nutrients.

Seed priming with KNO3 mediates biochemical processes to inhibit lead (Pb) toxicity in maize (Zea mays L.)

BACKGROUND Accumulation of lead (Pb) in agricultural soils has become a major factor for reduced crop yields and poses serious threats to humans consuming agricultural products. The present study investigated the effects of KNO3 seed priming (0 and 0.5% KNO3 ) on growth of maize (Zea mays L.) seedlings exposed to Pb toxicity (0, 1300 and 2550 mg kg-1 Pb). RESULTS Pb exposure markedly reduced the growth of maize seedlings and resulted in higher Pb accumulation in roots than shoots. Pretreatment of seeds with KNO3 significantly improved the germination percentage and increased physiological indices. A stimulating effect of KNO3 seed priming was also observed on pigments (chlorophyll a, b, total chlorophyll and carotenoid contents) of Pb-stressed plants. Low translocation of Pb from roots to shoots caused an increased accumulation of total free amino acids and higher activities of catalase, peroxidase, superoxide dismutase and ascorbate peroxidase in roots as compared to shoot, which were further enhanced by exogenous KNO3 supply to prevent Pb toxicity. CONCLUSION Maize accumulates more Pb in roots than shoot at early growth stages. Priming of seeds with KNO3 prevents Pb toxicity, which may be exploited to improve seedling establishment in crop species grown under Pb contaminated soils.

Ethnopharmacological studies of indigenous plants in Kel village, Neelum Valley, Azad Kashmir, Pakistan

BackgroundThis explorative study was undertaken for the first time in Kel village located in the Upper Neelum Valley, Azad Kashmir, Pakistan. The purpose was to document the indigenous knowledge of the native people used in the preparation of herbal medicines.MethodsTo get the data on traditional uses of medicinal plants, 20 informants were interviewed. Quantitative ethnobotanical indices, i.e., use value (UV), relative frequencies of citation (RFC), informant consensus factor (Fic), fidelity level (FL), data matrix ranking (DMR), preference ranking (PR), and jaccard index (JI), were calculated for the recorded medicinal plants.ResultsA total of 50 medicinal plants belonging to 33 families used in 13 disease categories were documented. Leaves were the frequently used plant parts, and decoction was the commonly used method for herbal medicine. Plants with high use value were Berberis lycium (2.05), Impatiens glandulifera (1.95), Artemisia scoparia (1.75), Ageratum conozoides (1.75), and Achillea millefolium (1.7). The highest RFC value was calculated for Berberis lycium (0.75), Cynoglossum lanceolatum (0.65), and Impatiens glandulifera and Achillea millefolium (0.60 each). The maximum informant consensus factor was for urinary system, cardiac diseases, baldness, and abortion and miscarriage (1.00). Berberis lyceum (95%) used in jaundice, hepatitis, typhoid, fever, and tuberculosis disorders. Plants with maximum fidelity level (FL) were Berberis lycium (95%) followed by Dioscorea bulbifera, Impatiens glandulifera, and Artemisia vulgaris (90%). Olea ferruginea was the most multipurpose plant and exports (21.2%) was the leading threat in the area. The pearson correlation coefficient (0.500) showed a positive correlation between the use value and relative frequency of citation.ConclusionThe present study provides useful information about traditional uses of medicinal plants used by local communities in different ailments. The plants with the highest use values could be employed in pharmacological research and biotechnological approaches in order to achieve adequate revenue. Some of the plants in the study area are facing high threats of becoming rare, and conservation initiatives are needed to conserve them for sustainable management in the region.

250 years of hybridization between two biennial herb species without speciation

In 1759, Linnaeus convinced his followers that plants could hybridise by crossing flowers in the daisy family and producing intermediate offspring. These hybrids, between Tragopogon pratensis and T. porrifolius, exist naturally today in London, to all appearances the same. We find that most of the London hybrids are in their first generation, though we provide chromosomal evidence that one is a little older. These hybrids do not seem to have given rise to a new species, even though both parents have produced new hybrid species in the last century when crossed with T. dubius.

Protein problems in Bangladesh

The food consumption data of the 1962–64 Survey of Bangladesh were examined in the light of the latest recommendations of FAO/WHO for energy and protein. It was found that on average there was an energy deficit of 10.7 percent at the retail level and an excess of protein of the order of 7 percent at the safe level of intake. Energy deficiency was found in 13.8 percent of households. The incidence of protein deficiency rises from 12.3 percent to 26.1 percent when households with energy deficiency are taken into consideration. Protein deficiency as such is present only in 0.8 percent of the households compared with 11.5 percent of the households which are deficient in both protein and energy. The magnitude of deficiency of protein as well as of energy which results from maldistribution of food within the household has not yet been quantitated. The cultural emphasis that women must be the last to partake of the food prepared in the house and that the children also share the same food as prepared for the adul...