Photoacclimation was studied in tobacco leaves (Nicotiana tabacum cv Xanthi) infected with two strains of tobacco mosaic virus (TMV) and grown under different light and nitrogen nutrition regimes. Photosynthetic acclimation measured by the quantum yield and the maximum rate in saturating light of CO2-saturated photosynthesis was impaired to a greater extent in tobacco leaves infected with TMV s...

This review examines the hypotheses that developmental programmed cell death in leaves is mediated (i) by sugar starvation in the leaf cells or (ii) by sugar accumulation in these cells. Experimental evidence for both hypotheses is critically discussed and found to be lacking. For example, some papers show that sugars prevent senescence of cut leaves placed in darkness, and prevent low sugar le...

The combined effects of intensive management and planting of improved seedlings have led to large increases in productivity on intensively managed pine forests in the southeastern United States. To best match clones to particular site conditions, an understanding of how specific clones respond to changes in nutrition in terms of biomass partitioning, leaf physiology and biochemistry will be nec...

In Citrus, water, nutrient transport and thereby fruit production, are influenced among other factors, by the interaction between rootstock and boron (B) nutrition. This study aimed to investigate how B affects the anatomical structure of roots and leaves as well as leaf gas exchange in sweet orange trees grafted on two contrasting rootstocks in response to B supply. Plants grafted on Swingle c...

Nitrogen is a vital element in crops, and its management is a key measure to improve their yield and quality. Real-time monitoring of crop nitrogen content is needed to optimize products and crop production. In this paper we use chlorophyll fluorescence source to obtain pepper leaf image for machine vision and digital image processing and establish a greenhouse pepper leaf nitrogen content rapi...

Nutrient management in Eucalyptus plantations is critical for wood production and sustainable development. The biogeochemical mechanisms are not fully understood due to changes the spatiotemporal pattern of precipitation plantation management. nutrients released from litterfall important sources soil nutrition. We measured seasonal various types proportions their urophylla × E. grandis under co...

This study aimed to evaluate forage yield, tiller population density, canopy height, nutritional value as well cattle performance in alternate stocking from three tropical cultivars. The experiment followed a randomized block design, 3 x factorial scheme with replications. Three cultivars (Marandu, Massai and Xaraés) distributed nine hectares were evaluated dry season periods (transition wet/dr...

The stalk borer Eldana saccharina Walker (Lepidoptera: Pyralidae) is a major limiting factor in South African sugarcane production, while yield is also reduced by sugarcane thrips Fulmekiola serrata Kobus (Thysanoptera: Thripidae). Borer management options include appropriate nitrogen (N) and enhanced silicon (Si) nutrition; the effect of N on sugarcane thrips is unknown. We tested the effects ...

This paper will present and discuss some basic physiological effects of nitrogen (N) nutrition in the cotton plant. The general thesis will be that N deficiency generates several related, yet discrete and experimentally identifiable, effects. Overall, these effects are integrated at the whole-plant level to produce systematic alterations in growth, yield, earliness, and other agronomic characte...

Ivorian forest has been experiencing degradation for several decades despite reforestation efforts. The main cause of the failure policies is an important mortality at time planting (transplanting stress). To remedy this problem, mycorrhization technology based on beneficial effects arbuscular mycorrhizal fungi (AMF) could provide a sustainable solution. objective study was to evaluate AMF inoc...