Leaf dry mass per unit leaf area (LMA) is a central trait in ecology, but its anatomical and compositional basis has been unclear. An explicit mathematical and physical framework for quantifying the cell and tissue determinants of LMA will enable tests of their influence on species, communities and ecosystems. We present an approach to explaining LMA from the numbers, dimensions and mass densit...

The sweetpotato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae) MEAM1, is considered a serious pest of horticultural and many other crops. While eggplant (Solanum melongena) is one of the most favored host plants, the whiteflies exhibit preferences among different varieties. We hypothesized that certain morphological leaf characteristics of different varieties, like leaf trichome density, tri...

This research was carried out for evaluating phenotypic diversity and traits correlation in 60 almond genotypes and cultivars in nursery conditions. After preparation land and the bitter seeds of Shahroud22 genotype as seedling rootstocks planted in the autumn 2005. After the seed germination in the spring of the next year, the results of recorded data in 3rd may of 2006 showed that the planted...

the water deficiency is one of the serious problems in the arid zones. in order to investigate the effect of cycocel on different growth aspects of two olive cultivars (mary and mission), a greenhouse experiment was conducted using three factors of: cycocel at three levels (0, 500 and 1000 mg l-1), irrigation of three levels (irrigated at 5, 10 and 15 days intervals) and tow olive cultivars (ma...

We compared smooth-leaf okra- and normal-leaf upland cotton (Gossypium hirsutum L.) strains and cultivars for susceptibility to colonization by Bemisia tabaci (Gennadius) biotype B. Experiments were conducted at seven field sites, five at Holtville, CA, and two at Maricopa, AZ, during 1996-2000. Okra-leaf strains and cultivars, as a group, had lower numbers of adults, eggs, and nymphs compared ...

Aloe barbadensis Miller, commonly known as Aloe Vera is extensively used as a base element in preparation of medicine, cosmetics and food supplements. The objective of this study was to find out the effect of different levels of nitrogen on morphological and physiological characteristic of Aloe vera plants. Treatments included four levels of nitrogen (0, 500, 1000 and 1500 mg pot). After 12 mon...

We examined the relationship of yellow sticky trap captures of Bemisia tabaci (Gennadius) biotype B parasitoids to the local population of parasitoids as measured by leaf samples of parasitized whiteflies and mass release of parasitoids. Traps were placed in experimental collard and cowpea field plots in Charleston, SC, and in commercial organic fields of spring cantaloupe and watermelon in the...

The fossil record demonstrates that past climate changes and extinctions significantly affected the diversity of insect leaf-feeding damage, implying that the richness of damage types reflects that of the unsampled damage makers, and that the two are correlated through time. However, this relationship has not been quantified for living leaf-chewing insects, whose richness and mouthpart converge...

To evaluate the effects of iron application on growth characters of Calendula officinalis L. under end season water deficit condition, an experiment was conducted as split plot at the Research Farm of Faculty of Agriculture, Urmia University (latitude 37.53°N, 45.08°E and 1320m above sea level), Urmia, Iran in 2010. Treatments were irrigation (irrigation disruption at first, second, third harve...