to evaluate integrated weed management on yield and weed biomass of bean an experiment were conducted as a split plot based on randomized complete block design with three replications at the research station of agriculture  in damavand in 2014.main plot of the mechanical control (cultivation)levels including the application and no application of cultivator and sub-plots chemical control levels ...

The reaction of several plant chlorophyll-protein complexes with NaBH, has been studied by absorption spectroscopy. In all the complexes studied, chlorophyll b is more reactive than Chl a , due to preferential reaction of its formyl substituent at C-7. The complexes also show large variations in reactivity towards NaBH, and the order of reactivity is: LHCI > PSI1 complex > LHCII > PSI > P700 (i...

Subpicosecond fluorescence upconversion has been used to measure the rate of chlorophyll b to chlorophyll a electronic energy transfer in situ within the LHC pigment proteins of Chlamydomonas reinhardtii mutant C2. The time scale of energy transfer is 0.5 & 0.2 ps as determined from the rise time of chlorophyll a fluorescence following chlorophyll b excitation. Estimates of the energy-transfer ...

Cadmium as a heavy metal is also considered as a serious threat for the environment. This element is accumulated in soil through industrial processes as well as phosphate fertilizers and aggregates into the food chain. This study was conducted in order to investigate the different levels of cadmium effects on growth features of rapeseed (Brassica napus L.) plants. Root and shoot weight and heig...

The content of individual chlorophyll and carotenoid pigments is determined in three spinach varieties (Lorelei, Springfield, and Ballet) after processing. Raw spinach and spinach that is steam-blanched for 3, 9, or 15 min is stored frozen at -24 degrees C for 6 months. In addition, spinach is air-dried at 75 degrees C, packed in atmospheric air or nitrogen, and stored at ambient temperature fo...

In the original version of this Article, the Abstract contains a typographical error. " Additional experimentation illustrated how these effects amplified over time, resulting in greater primary producer biomass sediment chlorophyll a content (Chla) in the longer term ". should read: " Additional experimentation illustrated how these effects amplified over time, resulting in greater primary pro...

Electrochromic spectra of monolayers of carotenoids (lutein and ß -carotene) in contact with monolayers of chlorophylls and of pheophytin a are measured in thin capacitors. A specific inter­ action of one of the OH-groups of lutein with the Mg-atom of chlorophyll is found. The formation of this oriented complex accounts for the fact that a part of the electrochromic absorption-change of lutein ...

Environmental changes and human activities can have strong impacts on biodiversity and ecosystem functioning. This study investigates how, from a quantitative point of view, simultaneously both environmental and anthropogenic factors affect species composition and abundance of exploited groundfish assemblages (i.e. target and non-target species) at large spatio-temporal scales. We aim to invest...