Field-cage studies have indicated that prefruiting cotton (Gossypium hirsutum L.) is not nutritionally adequate to support extended longevity of overwintered boll weevils (Anthonomus grandis Boheman), but these studies did not separate the respective effects of environment and nutrition on survival. The longevity of trapcaptured overwintered weevils fed pre-fruiting cotton under controlled cond...

Abstract In order to evaluate the effects of drought stress and defoliation on sunflower, a study was conducted under controlled conditions. Treatments were a combination of three levels of drought ((100, 60 and 30 percent of Field Capacity (FC)) and three levels of defoliation (control, removal of either 4 or 6 leaves from lower part of the plant) laid out, in a Completely Randomized Design w...

Plants need to allocate some of their limited resources for defense against herbivores as well as for growth and reproduction. However, the priority of resource allocation within plants has not been investigated. We hypothesized that plants with extrafloral nectaries (EFNs) invest more chlorophyll around their EFNs-to support a high rate of carbon fixation there-than in other leaf parts of youn...

twenty-two bread wheat cultivars along with susceptible (sholeh) and resistant (azadi) control cultivars were evaluated for resistance to russian wheat aphid of two growth stages including seedling and stem elongation in greenhouse. five adult aphids per plant were used for infestation. leaf chlorosis at seedling and stem elongation stages and leaf rolling at seedling stage were measured. other...

abstract in order to evaluate the effects of drought stress and defoliation on sunflower, a study was conducted under controlled conditions. treatments were a combination of three levels of drought ((100, 60 and 30 percent of field capacity (fc)) and three levels of defoliation (control, removal of either 4 or 6 leaves from lower part of the plant) laid out, in a completely randomized design wi...

Aquilegia `Rose-White' flowered from seed in about five months without vernalization. GA4/7 treatment increased stem height, induced earlier flowering, and increased the number of flowers/ plant. Each of these responses, however, was dependent upon both rate (10, 25, or 50 ppm) and timing of application (4-, 8-, or 12-leaf stage). Treatment at the 4-leaf stage resulted in earlier flowering at a...

although water deficiency has been seriously taken up as a subject in reducing crop production in arid and semi–arid areas, nevertheless little information has been published regarding its effects on seed quality. to evaluate the effects of irrigation regimes (full irrigation (control), irrigation until flowering stage, irrigation until doughing stage and irrigation until eight-leaf stage) on g...

In this study, the relation between leaf area and its dimensions was estimated using a non-destructive method. This method is based on this fact that the leaf shape does not change during the growing season. In this method, leaf area during the growing season is estimated based on the dimensions of the smallest leaf in the initial stage of plant growth or at any growth stage by measuring the le...