This study investigated seasonal patterns in stoichiometric ratios, nutrient resorption characteristics, and nutrient use strategies of dominant tree species at three successional stages in subtropical China, which have not been fully understood. Fresh leaf and leaf litterfall samples were collected in growing and nongrowing seasons for determining the concentrations of carbon (C), nitrogen (N)...

BACKGROUND AND AIMS The amount of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco, EC 4.1.1.39) synthesized in a leaf is closely correlated with N influx into the leaf throughout its lifetime. Rubisco synthesis and N influx are most active in the young leaf during expansion, but are very limited in the senescent leaf. However, it is not established whether Rubisco synthesis can be obse...

salvia genus belongs to lamiaceae family that was used in ancient and its application in culinary, flavor cosmetics, food and drinking industries is important. in the present study to assess compatibility of salvia sclarea to field condition and determine its potential for medicinal and ornamental applications, wild seed were cultured in pots. after initial growth, seedlings at 6-8 leaf stage t...

Longleaf pine has been classified as very shade intolerant but leaf physiological plasticity to light is not well understood, especially given longleaf pine’s persistent seedling grass stage. We examined leaf morphological and physiological responses to light in one-year-old grass-stage seedlings and young trees ranging in height from 4.6 m to 6.3 m to test the hypothesis that young longleaf pi...

The present study was carried out in a field located at Department of Botany, University of Karachi where soil was treated with various concentrations of pesticides before sowing. Combined effects of pesticides on soybean growth and nutritive composition of seeds were observed. Pesticide treated soil had significant effects on leaf growth components such as leaf area ratio, leaf area index, spe...

BACKGROUND AND AIMS The phenotypes of grasses show differences depending on growth conditions and ontogenetic stage. Understanding these responses and finding suitable mathematical formalizations are an essential part of the development of plant and crop models. Usually, a marked change in architecture between juvenile and adult plants is observed, where dimension and shape of leaves are likely...

The water resource shortage in North China Plain is an increasing threat to the sustainabilityof wheat (Triticum aestivum L.) production. A two-year field experiment was conducted toexamine the effects of two supplemental irrigation (SI) methods on wheat flag leaf senescence,chlorophyll fluorescence and grain yield. The following field treatments were conducted:no irrigation (W0); SI with 60 mm...

Leaf senescence, the final stage of leaf development, is a complex and highly regulated process that involves a series of coordinated actions at the cellular, tissue, organ, and organism levels under the control of a highly regulated genetic program. In the last decade, the use of mutants with different levels of leaf senescence phenotypes has led to the cloning and functional characterizations...

Quantitative resistance against Leptosphaeria maculans in Brassica napus is difficult to assess in young plants due to the long period of symptomless growth of the pathogen from the appearance of leaf lesions to the appearance of canker symptoms on the stem. By using doubled haploid (DH) lines A30 (susceptible) and C119 (with quantitative resistance), quantitative resistance against L. maculans...

During grain formation stage (90 to 110 days), the youngest flag leaf of rice (Oryza sativa L. cv. Jaya) remained metabolically most active (as indicated by cellular constituents and enzyme activities) and the third leaf the least active. At the grain development stage (110 to 120 days) the above pattern of age-related senescence of the flag leaf completely changed and it senesced at a faster r...