Effects of grazing on cold desert shrubs: A simulation model based on relative growth rate

1981 ◽  
Vol 13 (1-2) ◽  
pp. 49-86 ◽  
Author(s):  
Ned Fetcher
Keyword(s):  
Growth Rate ◽  
Simulation Model ◽  
Relative Growth Rate ◽  
Cold Desert ◽  
Relative Growth ◽  
Desert Shrubs ◽  
Model Based

scholarly journals Seed mass effects on germination and growth of diverse European Scots pine populations

1994 ◽  
Vol 24 (2) ◽  
pp. 306-320 ◽  
Author(s):  
P.B. Reich ◽  
J. Oleksyn ◽  
M.G. Tjoelker
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Scots Pine ◽  
Field Experiments ◽  
Seed Mass ◽  
Growing Season ◽  
Turkish Population ◽  
Dry Mass ◽  
Relative Growth ◽  
Mass Effects

Seedlings of 24 European Scots pine (Pinussylvestris L.) populations were grown in controlled environment chambers under simulated photoperiodic conditions of 50 and 60°N latitude to evaluate the effect of seed mass on germination and seedling growth characteristics. Seeds of each population were classified into 1-mg mass classes, and the four classes per population with the highest frequencies were used. Photoperiod had minimal influence on seed mass effects. Overall, seed mass was positively related to the number of cotyledons and hypocotyl height. Populations differed significantly in seed mass effect on biomass. In northern populations (55–61°N), dry mass at the end of the first growing season was little affected by seed mass. However, dry mass in 9 of 15 central populations (54–48°N) and all southern (<45°N) populations correlated positively with seed mass. Relative growth rate was not related to seed mass within or across populations, and thus early growth is largely determined by seed mass. Relative growth rate also did not differ among populations, except for a geographically isolated Turkish population with the highest seed mass and lowest relative growth rate. After one growing season, height was positively correlated (r2 > 0.6) with seed mass in 15 populations. To check the duration of seed mass effects, height growth of 1- to 7-year-old field experiments established with the same seed lots were compared. Seed mass effects on height were strongest for 1-year-old seedlings and declined or disappeared by the age of 5–7 years among central and southern populations, but remained stable over that time in northern populations.

scholarly journals Over-expression of AQUA1 in Populus alba Villafranca clone increases relative growth rate and water use efficiency, under Zn excess condition

2015 ◽  
Vol 35 (2) ◽  
pp. 289-301 ◽  
Author(s):  
Andrea Ariani ◽  
Alessandra Francini ◽  
Andrea Andreucci ◽  
Luca Sebastiani
Keyword(s):  
Growth Rate ◽  
Water Use Efficiency ◽  
Relative Growth Rate ◽  
Water Use ◽  
Populus Alba ◽  
Relative Growth ◽  
Over Expression ◽  
Use Efficiency
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