PREMISE OF THE STUDY Relationships of leaf size and shape (physiognomy) with climate have been well characterized for woody non-monocotyledonous angiosperms (dicots), allowing the development of models for estimating paleoclimate from fossil leaves. More recently, petiole width of seed plants has been shown to scale closely with leaf mass. By measuring petiole width and leaf area in fossils, le...

The evaluation of leaf area is required in several agronomic studies given their importance to assess the plant growth. The objective of this study was to use statistical models to estimate leaf area of five clonal varieties of coffee (Coffea canephora) from linear dimensions (length and width maximum). Were used in the studies five varieties of Coffea canephora Pierre ex Froehner: Emcapa 8111,...

The breeding of wheat with greater early vigour has potential to increase water- and nutrient-use efficiency, as well as to improve weed competitiveness to raise crop yields profitably. Given that wheat is inherently conservative in its early growth, a sustained breeding effort was initiated to increase genetically seedling leaf area in developing novel high vigour germplasm. A recurrent select...

rounded leaf tip. The leaf collar marks the junction of the leaf blade and sheath and appears when the leaf is fully developed. Each leaf sheath originates at its own node on the plant stalk. The sheath surrounds and strengthens the stalk (culm). The flag leaf is the last to emerge on the plant and is considerably smaller than the other leaves. The panicle (head) emerges from the flag leaf shea...

Terminal drought stress decreases crop yields by inducing abscisic acid (ABA) and premature leaf senescence. As potassium (K) is known to interfere with ABA homeostasis we addressed the question whether there is genetic variability regarding the role of K nutrition in ABA homeostasis and drought tolerance. To compare their response to drought stress, two barley lines contrasting in drought-indu...

The effect of water stress on glutathione reductase and catalase activities was evaluated in leaf blades of field-grown winter wheat (Triticum aestivum L.). Wheat was sown at two seeding rates under both irrigated and dryland conditions. Flag leaves from dryland plants sown at 60 kilograms/hectare showed no change in either glutathione reductase or catalase activities per unit leaf area, while ...

to identify the high yielding lines with optimal characteristics, 40 recombinant inbred lines derived from a cross between ‘norstar’ (winter wheat) and ‘zagros’ (spring wheat) cultivars were examined using a randomized complete block design with three replications in 2014 at the research station of faculty of agriculture, university of tabriz, iran. the measured characters consisted of peduncle...

Mathematical models based on dynamic growth process of greenhouse melon leaves were built. Two experiments, involving different years, organic fertilizer rates and cultivar types in melon, were carried out for data acquisition. In each experiment, time-course observations of leaf morphological properties (leaf length and leaf width) on different leaf positions of melon were obtained. The result...

proper application of n fertilizer and its optimization for increasing the economic yield of rice is definitely important. in order to determine the best n application method and amount according to growth stages of hybrid rice, an experiment was carried out at experimental farm of rrii in a factorial experiment based on a randomized complete block design with 3 replications. the treatments inc...