The ch4 mutant of sweetclover (Melilotus alba) has previously been demonstrated to be temperature- and photoperiod-sensitive for the accumulation of chlorophyll. Pigment content of ch4 mutant leaves was examined as a function of trifoliolate mass, an index of leaf development. Inhibition of chlorophyll accumulation caused by increased growth temperature or decreased photoperiod can be attenuate...

Stoichiometric homeostasis is the ability of plants remaining their element composition relatively stable regardless of changes in nutrient availability, via various physiological mechanisms. Nutrient resorption is one of such key mechanisms, but whether and how nitrogen and phosphorus homeostasis and resorption in plants would change with growth-stages under variable nutrient supply was unclea...

The phenylpropanoid pathway serves as a rich source of metabolites in plants. It is required for the biosynthesis of lignin and acts as a starting point for the production of many other important compounds involved in growth and development. Phenylalanine ammonia-lyase (PAL) catalyzes the first step of the phenylpropanoid pathway. PAL gene expression changes during the growth and development of...

in order to determine the effects of water deficit at different growth stages of sugar beet and optimal usage of water on quality and quantity characters of sugar beet, a factorial experiment based on randomized complete block design was conducted with 13 treatments and four replications in 2000 and 2001 in agricultural research center of hamadan. for the first factor, irrigation withheld in th...

This study investigated seasonal patterns in stoichiometric ratios, nutrient resorption characteristics, and nutrient use strategies of dominant tree species at three successional stages in subtropical China, which have not been fully understood. Fresh leaf and leaf litterfall samples were collected in growing and nongrowing seasons for determining the concentrations of carbon (C), nitrogen (N)...

Selective herbicides have been used for weed control since the turn of the century, but the use of 2,4-dichlorophenoxyacetic acid (2,4-D.) has developed during the past decade. This chemical is valuable because numierous broadleaved weeds are susceptible to low rates of application and mnany agronomic crops are tolerant to these small dosages. Barley has been considered to be one of the relativ...

The appropriate timing of developmental transitions is critical for adapting many crops to their local climatic conditions. Therefore, understanding the genetic basis of different aspects of phenology could be useful in highlighting mechanisms underpinning adaptation, with implications in breeding for climate change. For bread wheat (Triticum aestivum), the transition from vegetative to reprodu...

in order to study grain yield, yield components and growth indices in wheat, the experiment was carried out with five wheat cultivars at rbcd arrangement with 4 replications at gorgan university of agricultural sciences and natural resources. the cultivars included zagros, tajan, kohdasht, durum and n81-18 line. to measure studied traits (leaf, stem and shoot dried weight and leaf area) fifteen...