%0 Journal Article
	%A Manoochehr Gholipoor
	%D 2009
	%J International Journal of Agricultural and Biosystems Engineering
	%B World Academy of Science, Engineering and Technology
	%I Open Science Index 25, 2009
	%T Evaluating the Response of Rainfed-Chickpea to Population Density in Iran, Using Simulation
	%U https://publications.waset.org/pdf/7978
	%V 25
	%X The response of growth and yield of rainfed-chickpea
to population density should be evaluated based on long-term
experiments to include the climate variability. This is achievable just
by simulation. In this simulation study, this evaluation was done by
running the CYRUS model for long-term daily weather data of five
locations in Iran. The tested population densities were 7 to 59 (with
interval of 2) stands per square meter. Various functions, including
quadratic, segmented, beta, broken linear, and dent-like functions,
were tested. Considering root mean square of deviations and linear
regression statistics [intercept (a), slope (b), and correlation
coefficient (r)] for predicted versus observed variables, the quadratic
and broken linear functions appeared to be appropriate for describing
the changes in biomass and grain yield, and in harvest index,
respectively. Results indicated that in all locations, grain yield tends
to show increasing trend with crowding the population, but
subsequently decreases. This was also true for biomass in five
locations. The harvest index appeared to have plateau state across
low population densities, but decreasing trend with more increasing
density. The turning point (optimum population density) for grain
yield was 30.68 stands per square meter in Isfahan, 30.54 in Shiraz,
31.47 in Kermanshah, 34.85 in Tabriz, and 32.00 in Mashhad. The
optimum population density for biomass ranged from 24.6 (in
Tabriz) to 35.3 stands per square meter (Mashhad). For harvest index
it varied between 35.87 and 40.12 stands per square meter.
	%P 57 - 64