the beet armyworm spodoptera exigua (hübner) is a serious and economically important pest of solanaceous crops worldwide. the nutritional indices of this pest on three host plants including pepper capsicum frutescens, eggplant solanum melongena and tomato solanum lycopersicum were determined under laboratory conditions at 26 ± 1 °c, 60 ± 5% rh and 16: 8 (l: d) h. the highest relative consumptio...

For niche differences to maintain coexistence of sympatric species, each species must grow and/or survive better than each of the others in at least one set of conditions (i.e., performance trade-offs). However, the extent of niche differentiation in tropical forests remains highly debated. We present the first test of performance trade-offs for wild seedlings in a tropical forest. We measured ...

The ability of invasive plants to achieve higher relative growth rates (RGR) than their native counterparts has been widely documented. However, the mechanisms allowing invasives to achieve higher RGR are poorly understood. The objective of this study was to determine the basis for RGR differences between native and invasive forbs that have widely invaded nutrient-poor soils of the Intermountai...

The present study provides a description of the morphological, histological and histochemical development, and the ecological implications of red porgy larvae reared in mesocosm, from hatching to 30 days after hatching (DAH). Four development stages were defined by body total length (TL), in agreement with major patterns of larval organogenesis. The first stage was characterized by the highest ...

Interstocks can reduce toxic ion accumulations in leaves of budded citrus trees, but the mechanism is not understood. We grew sour orange (Citrus aurantium L.; SO) seedlings, budded trees of 'Salustiano' orange (Citrus sinensis L. Osbeck; SAO) on SO, 'Verna' lemon (Citrus limon L. Burm. f; VL/SO) and interstock trees (VL/SAO/SO) in pots of sand watered with nutrient solution containing 5 (contr...

Throughout the western United States, the invasive annual grass, medusahead (Taeniatherum caputmedusae L. Nevski), is rapidly invading grasslands once dominated by native perennial grasses, such as bluebunch wheatgrass (Pseudoroegneria spicata (Pursh) A). It is also invading grasslands dominated by less undesirable invasive annual grasses, especially cheatgrass (Bromus tectorum L.). Understandi...

This paper investigates the effects of uptake of nitrate and the availability of internal N reserves on growth rate in times of restricted supply, and examines the extent to which the response is mediated by the different pools of N (nitrate N, organic N and total N) in the plant. Hydroponic experiments were carried out with young lettuce plants (Lactuca sativa L.) to compare responses to eithe...

Industrial discharge of active pharmaceutical ingredients (APIs) into the environment in some middle- and low-income countries is not sufficiently regulated. The phytotoxicity of metronidazole (FLAGYL)-one of the most commonly used over the counter (OTC) antibiotics, to soybean (Glycine max) is investigated. Relative growth rate (RGR) expressed in gram per gram per day (gg-1d-1) was applied to ...

BACKGROUND AND AIMS Studies on the effects of sub- and/or supraoptimal temperatures on growth and phosphorus (P) nutrition of perennial herbaceous species at growth-limiting P availability are few, and the impacts of temperature on rhizosphere carboxylate dynamics are not known for any species. METHODS The effect of three day/night temperature regimes (low, 20/13 °C; medium, 27/20 °C; and hig...