Effects of Nitrogen Supply on Water Stress and Recovery Mechanisms in Kentucky Bluegrass Plants

Abstract

Non-irrigated crops in temperate and irrigated crops in arid regions are exposed to an incessant series of drought stress and re-watering. Hence, quick and efficient recuperation from drought stress may be amongst the key determinants of plant drought adjustment. Efficient nitrogen (N) nutrition has the capability to assuage water stress in crops by sustaining metabolic activities even at reduced tissue water potential. This study was designed to understand the potential of proper nutrition management by studying the morphological and physiological attributes, and assimilation of nitrogen in Kentucky bluegrass under drought stress. In present study, one heterogeneous habitat and four treatments homogenous habitats each with four replications were examined during field trial. Drought stress resulted in a significant reduction in the nitrogen content of both mother and first ramets, maximum radius, above and below ground mass, number of ramets per plot, leaf water contents and water potential and increased the carbon content and the C:N ratio in both homogenous and heterogeneous plots compared to well-watered and nutritional conditions. Observation using electron microscopy showed that drought stress shrunk the vessel diameter, circumference and xylem area, but increased the sieve diameter, and phloem area in the leaf crosscutting structure of Kentucky bluegrass, first, second, and third ramet leaf. Thus, it can be concluded that water stress markedly reduced all the important traits of Kentucky bluegrass, however, proper nutritional management treatment resulted in the best compensatory performance under drought assuaging its adversity up to some extent and may be considered in formulating good feasible and cost-effective practices for the environmental circumstances related to those of this study.

Impact of Nitrogen Addition on Physiological, Crop Total Nitrogen, Efficiencies and Agronomic Traits of the Wheat Crop under Rainfed Conditions

“…The relationship of grain yield with crop physiological traits showed that stomatal conductance could be the major determinant of the grain yield. Since global temperature and frequent occurrence of drought could maximize N losses, new avenues for improving crop productivity must thus be exploited [68][69][70][71][72].…”

Interactive Effects of N-, P- and K-Nutrition and Drought Stress on the Development of Maize Seedlings

“…This might indicate that current soil test methods used do not adequately indicate the soil nutrient supply for the given soil. Optimal nutrient levels of fertilization are even more important under water deficit conditions, since reduced nutrient availability is one of the major factors limiting plant growth under drought [5,9,14]. To our knowledge, this is the first report of a comparison of maize seedling growth with N, P and K nutrient application individually or in combination under drought and well-watered conditions.…”

“…Thus, nutrient supply strongly affects crop productivity under drought conditions, but this is also very complex [8][9][10]. The positive effects of N and P on plant growth under drought conditions are attributed to an increase in water-use efficiency, stomatal conductance [11][12][13][14], photosynthesis and ATPase activity [5,15], as well as higher cell membrane stability and improved osmotic adjustment [16,17]. However, K increases a plant s drought tolerance through its functions in…”

Mechanisms of Environmental Stress Tolerance in Turfgrass

“…Dry forage yield, chlorophyll content and RWC of tall fescue were found to decrease; on the contrary, the carotenoid and proline content increased under drought stress [86]. The photosynthesis, stomatal conductance, Rubisco activity, and nitrogen content of Kentucky bluegrass were severely disrupted by drought conditions [91,92]. It was reported that the activities of APX, peroxidase (POD) and glutathione peroxidase (GPX) in Kentucky bluegrass increased and then decreased with drought stress, but in desert wheatgrass (Agropyron desertorum) a continuous increase in activity of these enzymes was detected [93].…”