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Start Over Coverage 194-200

1. Jaký prospěch máme ze studia historie vědy?: (Předneseno na konferenci "Den Československého časopisu pro fyziku", Praha 22. 11. 2005)

Creator:
Kraus, Ivo
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
Lenard, Philipp, 1862-1947, Stark, Johannes, 1874-1957, dějiny vědy, vzdělanost, interdisciplinární aspekty, history of science, educational attainment, interdisciplinary aspects, 6, and 53
Language:
Czech
Description:
Čím lépe se ve vědě chceme uplatnit, tím dokonalejším rozhledem po mezioborových a společenských vazbách bychom měli být vybaveni. Ke splnění takového cíle přispívá i znalost vývoje jednotlivých vědních oborů. Historická zkušenost může být pro naše rozhodování poučná i inspirativní., Ivo Kraus., Obsahuje seznam literatury, and Text doplněn dvěma medailonky nobelistů Lenarda a Starka pod čarou
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2. The role of iron (Fe) in the population dynamics of pistachio psyllid, Agonoscena pistaciae (Hemiptera: Aphalaridae) in Pistacia orchards

Creator:
Dehghani-Yakhdani, Hossein , Iranipour, Shahzad , Mehrnejad, Mohammad Reza , and Farshbaf-Pourabad, Reza
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
Hemiptera, Aphalaridae, Agonoscena pistaciae, pistachio psyllid, Pistacia, host plant quality, life table, nutrient fertilizer, population density, intrinsic rate of increase, and central Iran
Language:
English
Description:
The common pistachio psyllid (CPP) is thought to respond to nutrient availability in pistachio trees. We determined the effect of a deficiency of leaf iron (Fe) has on the abundance of the pistachio psyllid at a regional scale. First, we monitored the abundance pistachio psyllid in four pistachio orchards (24 trees as 24 repetitions) located in Maybod County, Yazd province in the centre of Iran and then measured leaf nutrient levels. Orchards were located up to 2.6 km apart. Multivariate regressions were used to determine the relationship between leaf nutrients and CPP population growth. The results indicate that the number of psyllid eggs and population growth rate of the nymphs was negatively correlated with Fe levels in the leaves, while peak numbers of psyllid eggs were positively correlated with the levels of Cu in the leaves. In a manipulative field experiment, we conducted two experiments: (1) pistachio trees treated with iron compared with control trees, and (2) pistachio trees previously treated with iron were treated with ammonium sulphate and compared with trees treated with ammonium sulphate. In the first experiment, psyllids in leaf disc-cages had a significantly greater intrinsic rate of population increase and net reproductive rate on Fe-treated trees than the control trees (Stage 1). In the second experiment, psyllids in leaf disc-cages had similar intrinsic rates of population increase and net reproduction both on the ammonium sulphate treated trees (control) and those previously treated with iron. This indicates that iron may have reacted negatively with nitrogen content of the leaves. In general, these findings indicate that when there is a deficiency of iron in the leaves, the application of nitrogen fertilizer had little effect on the performance of CPP and may have played a minor role in the population dynamics of CPP, but the application of a Fe fertilizer without considering the nitrogen content of the leaves may lead to a population outbreak.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public