crop simulation models are increasingly used in agriculture. these models help in saving time and expenses. the objective of this study was to evaluate cropsyst model in predicting development, growth and yield of wheat cultivars from golestan province. to do this, experimental data from different experiments were gathered for kohdasht, shiroodi, tajan and zagros. model performance in simulatin...

The photosynthetic potential of leaves and chloroembryos of Cyamopsis tetragonoloba (L.) Taub as measured by (14)C-bicarbonate fixation, Hill activity, and in vivo fluorescence transients is compared. On a chlorophyll basis, dark fixation of NaH(14)CO(3) in chloroembryos was 1.5 times higher than that of the leaf, whereas carbon fixation under illumination was threefold higher in the leaf than ...

Abstract Some of the changes in physiological indicators during growth and development litchi fruit grown Vietnam were studied. The length diameter fruits reached their maximum value at 10 weeks after anthesis. content chlorophyll peel its highest 6 decreased rapidly. carotenoids was low formation then increased rapidly until ripening. vitamin C reducing sugar continuously a slightly. starch li...

In wheat, stem water soluble carbohydrates (WSC), composed mainly of fructans, are the major carbon sources for grain filling during periods of decreasing photosynthesis or under drought stress after anthesis. Here, in a field drought experiment, WSC levels and associated enzyme activities were followed in different stem segments (peduncle, penultimate internode, lower parts of stem, and sheath...

sowing date and irrigation are two constrain factors for maize production. these factors can be simulated by using ceres-maize model. for this purpose two experiments (each one at two years) were carried out at agricultural research station of gorgan which is golestan province capital. the model was calibrated using three treatments of optimum irrigation and without stress in 2012 and two treat...

Maize production in Thailand is increasingly suffering from drought periods along the cropping season. This creates need for rapid and accurate methods to detect crop water stress prevent yield loss. The study was, therefore, conducted improve efficacy of thermal imaging assessing maize prediction. experiment was carried out under controlled field conditions Phitsanulok, Thailand. Five treatmen...

Phenological traits often show variation within and among natural populations of annual plants. Nevertheless, the adaptive value of post-anthesis traits is seldom tested. In this study, we estimated the adaptive values of pre- and post-anthesis traits in two stressful environments (water stress and interspecific competition), using the selfing annual species Arabidopsis thaliana. By estimating ...

A common observation in different plant species is a massive abscission of flowers and fruitlets even after adequate pollination, but little is known as to the reason for this drop. Previous research has shown the importance of nutritive reserves accumulated in the flower on fertilization success and initial fruit development but direct evidence has been elusive. Avocado (Persea americana) is a...