cultivated area, yield and production trend of wheat (triticum aestivum l.), barley (hordeum vulgare l.), potato (solanum tuberosum l.), alfalfa (medicago sativa l.) and chickpea (cicer arietinum l.) as the main crops of kurdistan province were studied during 1983-2006 using time series analysis and the situation of future were predicted for 2006-2021 period. the results showed that the cultiva...

This research shows that a portfolio of wheat varieties could enhance profitability and reduce risk over the selection of a single variety for Kansas wheat producers. Many Kansas wheat farmers select varieties solely based on published average yields. This study uses portfolio theory from business investment analysis to find the optimal, yield-maximizing and riskminimizing combination of wheat ...

the objective of this study was to investigate the effects of addition of pulses in crop sequences, crop residue management, and application of fertilizer n on soil nitrogen content, soil organic carbon, nutrient uptake, and its consequences for wheat yields. the field experiments were carried out from 2009 to 2012 in the sub-humid and sub-tropical zone of northern india. the treatments were (i...

The aim of the present study was to evaluate the response of grain yield, phosphorus (P) use efficiency (PUE, g yield g–1 P available) and related root traits of wheat and pea to different P availabilities in a high yielding environment (e.g.: yield higher than 10 Mg ha-1 for wheat). Two experiments were conducted in southern Chile. Treatments consisted of the combination of (i) two crops (spri...

Several methods have been proposed to simulate yield in crop simulation models. In this work, we present a simple method to estimate harvest index (HI) of grain crops based on fractional post-anthesis phase growth ( fG = fraction of biomass accumulation that occurred in the post-anthesis phase). We propose that HI increases in a linear or curvilinear fashion in response to fG. The linear model ...

The effect of elevated [CO2] on wheat (Triticum aestivum L. Veery 10) productivity was examined by analysing radiation capture, canopy quantum yield, canopy carbon use efficiency, harvest index and daily C gain. Canopies were grown at either 330 or 1200 micromoles mol-1 [CO2] in controlled environments, where root and shoot C fluxes were monitored continuously from emergence to harvest. A rapid...