Tu, Yicheng, M.S., Purdue University, December, 2000. Endogenous Gibberellins in Developing Apple Seeds in Relation to Biennial Bearing. Major Professor: Peter M. Hirst. It is believed that Gibberellins (GA) produced in apple seeds act as an inhibitory signal to flower induction in the neighboring buds. As an exception, GA4 is not inhibitory and sometimes found to be promotive to apple flowerin...

To describe plant phenological patterns and correlate functioning for the quantity and quality of resources available for the pollinator, it is crucial to understand the temporal dynamics of biological communities. In this way, the pollination syndromes of 46 species with different growth habits (trees, shrubs, herbs, and vines) were examined in an area of Caatinga vegetation, northeastern Braz...

The strong climatic fluctuation observed during the major cocoa production period with reductions in rainfall and rising temperatures lead to a low graining index. This situation makes marketing difficult for producers. stability of quantitative productivity parameters six cacao clones on farm was analyzed main season. Flowering, average pod weight, number beans per pod, bean size, index were a...

Climate change is affecting high-altitude and high-latitude communities in significant ways. In the short growing season of subarctic habitats, it is essential that the timing and duration of phenological phases match favorable environmental conditions. We explored the time of the first appearance of flowers (first flowering day, FFD) and flowering duration across subarctic species composing di...

BACKGROUND AND AIMS Understanding the demography of long-lived clonal herbs, with their extreme modularity, requires knowledge of both their short- and long-term survival and ramet growth patterns. The primary objective of this study was to understand the dynamics of a clonal forest herb, Trillium recurvatum, by examining temporal and small-scale demographic patterns. We hypothesized: (i) there...

We examined patterns of genetic variance and covariance in two traits (i) carbon stable isotope ratio delta13C (dehydration avoidance) and (ii) time to flowering (drought escape), both of which are putative adaptations to local water availability. Greenhouse screening of 39 genotypes of Arabidopsis thaliana native to habitats spanning a wide range of climatic conditions, revealed a highly signi...

Seed morph, abiotic conditions and time of germination can affect plant fitness, but few studies have tested their combined effects on plasticity of plant life history traits. Thus, we tested the hypothesis that seed morph, germination season and watering regime influence phenotypic expression of post-germination life history traits in the diaspore-heteromorphic cold desert winter annual/spring...

due to limited water resources, applying efficient water use in agriculture is very important. this experiment was carried out in kabootarabad agricultural research station for two years using split plots in a randomized complete block design with four replications. six irrigation treatments based on evaporation from class a pan were applied as the main factor at three cotton growing stages, na...

The effect of spring burning, fertilization, and atrazine on herbage yield of warmand cool-season grasses, flowering stalk density, and seed yield of selected warm-season grasses was determined on a remnant prairie and a restored prairie located near Lincoln and Center, Nebraska, respectively. Sites were burned in mid-April 1987 and followed by application of fertilizer (112 kg N/ha at the remn...

An observed increase in air temperature can lead to significant changes in the phenology of plants and, consequently, changes in agricultural production. The aim of the study was to evaluate the spatial differentiation of thermal resources in Poland and their variability during a period of changing thermal conditions in Europe. Since the variability of thermal conditions is of paramount importa...