Mineral nutrients taken up by the roots are, as a rule, transported in the xylem to the shoot, and photoassimilates transported in the phloem to the roots. According to the Thornley model of photosynthate partitioning, nutrient deficiencies should favour photosynthate partitioning to the roots. Examples are cited to show that this preferential partitioning is dependent on phloem mobility and he...

Dog rose (Rosa canina) has been using as a rootstock for ornamental roses also it is one of the medicinal plants. It can be propagated under in vitro conditions. After removing chilling requirement of buds, axillary wood buds of dog rose were cut in three nodal positions (lower, middle and terminal) on the stem and then explants after decontamination, cultured on Murashige and Skoog medium (MS ...

Nitrapyrin (Nt) at 10 ppm, compared to water control, added to a soil-sand-peat medium decreased shoot growth of tomatoes (Lycopersicon esculentum Mill. cv. Marglobe) grown with NOJ-N nutrition but had no effect on growth with NH.-N nutrition. While plant water stress was decreased by NI compared to the control with NOJ-N nutrition, the toxic effect of increased uncombined NH. concentration in ...

Heavy atmospheric nitrogen (N) deposition has been associated with altered nutrient cycling, and even N saturation, in forest ecosystems previously thought to be N-limited. This observation has prompted application to such forests of non-N mineral nutrients as a mitigation measure. We examined leaf gas-exchange, leaf chemistry and leaf and shoot morphological responses of Acer saccharum Marsh. ...

To study the impact of ozone (O3) and O3 plus CO2 on aspen growth, we planted two trembling aspen clones, differing in sensitivity to O3 in the ground in open-top chambers and exposed them to different concentrations of O3 and O3 plus CO, for 98 days. Ozone exposure (58 to 97 microl l(-1)-h. total exposure) decreased growth and modified crown architecture of both aspen clones. Ozone exposure de...

A novel protocol for production of multiple shoot tip clumps of Keelar nelli (Phyllanthus amarus Schum. & Thom.) were developed in vitro from shoot tip explants cultured on Murashige and Skoog (MS) medium containing only BAP or BAP with NAA, 3% sucrose and 0.8% agar. The addition of the following combination of growth substances 0.1mgLBAP and 0.05mgLNAA, caused an extensive proliferation of mul...

The antimycotic potential of Datura metel (syn. Datura alba Nees.) was investigated in vitro against Ascochyta rabiei, the cause of chickpea blight disease. The pathogen was exposed to various n-hexane concentrations (1, 2, 3 and 4% w/v) of shoot and root extracts of D. metel using poisoning food technique. All the employed concentrations of both root and shoot extracts significantly suppressed...

In vitro techniques may provide a suitable tool for effective propagation and conservation of plant species representing various ecological niches. The elaboration of such protocols is also prerequisite for selection of heavy-metal-tolerant plant material that could be afterwards used for restoration or remediation of polluted sites. In this study, culture protocol for Gypsophila fastigiata pro...

R82 (sym-17), a stable mutant of Pisum sativum L. cv Sparkle, is described. The shoot growth of the mutant was less than that of its parent under light or dark growth conditions. Gibberellic acid treatment did not normalize the shoot growth of R82. The mutant had thick and short roots. It formed few nodules, but the specific nitrogenase activity was not affected. R82 produced and contained more...

The effect of different concentrations of hexavalent Cr on growth and biochemical parameters of two T. aestivum cultivars (Punjab-11 and Sehar-06) was investigated. No significant inhibition of seed germination was observed in both the cultivars at all the tested concentrations (P ˃ 0.05). A significant decrease in root length for both the cultivars was observed at all the Cr concentrations as ...