In seed-dispersal mutualisms, the number of fruit a plant displays is a key trait, as it acts as a signal for seed dispersers that entails fruit removal and exportation of reproductive units (fruit crop size hypothesis). Although this hypothesis has gained general acceptance, forces driving the shape and strength of natural selection exerted by birds on fruit crop size remains an unresolved mat...

the purpose of this study is to investigate comparative advantages of corn in comparison with other competitor crops. to do so, linear programming, to 2004-2005 data related to classic index (drc) in kermanshah province was applied. results showed that corn has comparative advantages in all regions of kermanshah province while in optimal cultivation pattern of 37.5 percentages of regions in exi...

Under commercial poinsettia production conditions we compared two patterns of parasitoid release for the aphelinid whitefly parasitoid Eretmocerus eremicus Rose and Zolnerowich. We compared the currently used pattern of a fixed weekly release number (3 females per plant per week) to an experimental pattern in which more parasitoids were released early in the crop (wks 1-8), followed by a lower ...

BACKGROUND AND AIMS When examining the growth patterns of rice crops for a 5-year period, it was found that the time course of accumulation of above-ground dry matter did not follow a simple sigmoid curve as expected for a monocarpic plant. Instead, there was a decrease in growth around flowering, followed by an increase and then a final decrease of growth at crop maturity. There are two nearly...

Crop planting patterns are an important component of agricultural land systems. These have been significantly changed due to the combined impacts climatic changes and socioeconomic developments. However, extent these their possible on environment, terrestrial landscapes rural livelihoods largely unknown lack spatially explicit datasets including crop patterns. To fill this gap, study proposes a...

Irrigation management has gained significance due to growing social needs and increasing command for food grains while the available resources have remained limited and scarce. Irrigation management includes optimal allocation of water for irrigation purposes, optimal cropping pattern for a given land area and water availabilities with an objective to maximize economic returns. In the present s...

The purpose of this study is to evaluate the progress and regional variations of crop production in Bangladesh. The secondary data were used and collected for the years 1980-81 to 2002-03 from the ‘Statistical Yearbooks of Bangladesh’, ‘Yearbook of Agricultural Statistics’ and population census of different years. The study was conducted during the period from September 2006 to February 2008. A...