scholarly journals Interaction Effect of Arbuscular Mycorrhiza and Redroot Pigweed (Amaranthus retroflexus L.) on Growth and Yield of Sunflower under Water Stress Conditions

2020 ◽  
Vol 9 (4) ◽  
Author(s):  
F Shafique ◽  
Q Ali ◽  
A Malik

Many biotic and abiotic factors affect plant growth and its development. Maize growth usually increased under excess water availability but less tolerant against water deficit stress condition. In this study, we investigated the effects of water stress on the growth and yield of maize. We found that severe water stress during the seedling stage had a greater effect on the growth and development of maize. Three maize varieties (Pak afghoi, Neelum, White corn) were used to find out the effects on growth of plant under drought or water deficit environmental conditions. Different drought stress treatments (Control, 20% irrigation water, 40% irrigation water, 60% irrigation water, 80% irrigation water) were imposed to growing seedlings after germination. The treatments were applied after 4 times each after 7 days interval and data for different morphological traits was recorded each time. The recorded data was pooled and analyzed for analysis of variance to access the significance of results. The ANOVA indicated the differences among five different genotypes and 5 different treatments for all parameters were significant. Tukey’s test indicated that maize genotype White corn was more tolerant while genotype Neelum was more sensitive for drought stress conditions therefore, white corn maize genotype may be helpful for the development of drought tolerance maize varieties and hybrids. Positive and significant correlation was found for shoot length with all other studied traits under drought stress conditions. Treatment control, 80% and 60% irrigation water was less adverse for maize growth while treatment 20% irrigation water highly affected all maize genotypes, therefore maize genotypes may be grow under treatment 60% irrigation water.


Weed Science ◽  
2020 ◽  
pp. 1-6
Author(s):  
Asad M. Khan ◽  
Ahmadreza Mobli ◽  
Jeff A Werth ◽  
Bhagirath S. Chauhan

Abstract Slender amaranth (Amaranthus viridis L.) and redroot pigweed (Amaranthus retroflexus L.) are increasingly problematic weeds of summer crops in Australia. Water is considered the most limiting factor in an agroecosystem, and water stress adversely impacts the growth and reproduction of plant species. The primary objective of this study was to determine the growth and fecundity of two Australian biotypes (Goondiwindi and Gatton) of A. viridis and A. retroflexus under water-stress conditions. Four water-stress treatments (100%, 75%, 50%, and 25% field capacity [FC]) at a 4-d irrigation interval were chosen. No difference was observed for growth and seed production between the two biotypes of both species when grown under varying soil moisture regimes. At 100% FC, A. viridis produced 44 g plant−1 aboveground biomass and 1,740 seeds plant−1. The maximum growth (46 g plant−1) and seed production (3,070 seeds plant−1) of A. retroflexus were observed at 100% FC. The growth and seed production of both species were reduced with increased water-stress levels. Both weeds responded to water stress by decreasing the shoot:root biomass ratio. However, A. viridis (290 seeds plant−1) and A. retroflexus (370 seeds plant−1) were able to produce a significant number of seeds per plant even at 25% FC. Results suggest that both weeds will produce seeds under water-limiting conditions. Therefore, management strategies are required to minimize the growth and survival of weeds in water-deficit conditions.


2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Nahlaa Jamal Hussain Hayyawi ◽  
Mohammed H. Al-Issawi ◽  
Abdullah A. Alrajhi ◽  
Hanady Al-Shmgani ◽  
Hail Rihan

Water stress has a negative impact on the yield and growth of crops worldwide and consequently has a global impact on food security. Many biochemical changes occur in plants as a response to water stress, such as activation of antioxidant systems. Molybdenum (Mo) plays an important part in activating the expression of many enzymes, such as CAT, POD, and SOD, as well as increasing the proline content. Mo therefore supports the defence system in plants and plays an important role in the defence system of mung bean plants growing under water stress conditions. Four concentrations of Mo (0, 15, 30, and 45 mg·L−1) were applied to plants, using two approaches: (a) seed soaking and (b) foliar application. Mung bean plants were subjected to three irrigation intervals (4 days control, 8 days-moderate water stress, and 12 days severe water stress). Irrigation intervals caused a reduction in the growth and production of mung beans, especially when the plants were irrigated every 12 days. It also led to the accumulation of malondialdehyde (MDA) and hydrogen peroxide (H2O2) in mung bean leaves, and these are considered to be indicators of lipid peroxidation and Reactive Oxygen Species (ROS) accumulation, respectively. On the other hand, applying Mo enhanced some growth and yield traits and also enhanced the defence system by upregulating antioxidant expressions, such as proline, catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD). The MDA content did not change under the effect of Mo treatments. However, H2O2 content slightly increased with an increase of Mo concentration of up to 30 mg·L−1 followed by a significant decrease when Mo concentration was increased to 45 mg·L−1. It can be concluded that Mo is a robust tool for the activation of the defence system in mung beans.


Weed Science ◽  
2005 ◽  
Vol 53 (5) ◽  
pp. 702-708 ◽  
Author(s):  
Erin R. Haramoto ◽  
Eric R. Gallandt

Field studies have shown that weed density and biomass were lower in crops following incorporation of brassica cover crops compared with fallow but have not determined whether weed-suppressive effects are solely a consequence of reduced establishment, as evidenced in our companion paper, reduced growth of established plants, or both. In 2002 and 2003, canola and yellow mustard were seeded in early May, mowed in early July, and the residues incorporated. Green bean and redroot pigweed were then planted at fixed densities. Plant height and biomass were measured weekly; leaf area and biomass of component plant parts were measured at three harvests. Based on analysis of variance (ANOVA) at discreet sampling points, growth of redroot pigweed and green bean in monoculture or mixture were similar following fallow and incorporated brassica cover crops. However, based on aboveground biomass fitted to a Richards function, redroot pigweed growth in monoculture was reduced by the yellow mustard cover crop compared with fallow in both years (P = 0.007), but the magnitude of this effect was small; the canola cover crop did not affect growth (P = 0.179). Brassica cover crops did not reduce redroot pigweed growth when it was grown in mixture with green bean (P ≥ 0.382). Redroot pigweed competition reduced green bean yield, but incorporated brassica cover crops did not affect green bean growth and yield, nor did they confer a competitive advantage to the crop. Thus, brassica cover crops may suppress the growth of established weed and crop plants, but the magnitude of suppression was less than previously documented for effects on weed establishment.


2007 ◽  
Vol 58 (1) ◽  
pp. 29 ◽  
Author(s):  
Agueda González ◽  
Isaura Martín ◽  
Luis Ayerbe

Terminal drought is the main factor limiting the yield of cereals in the central area of Spain because rainfall is scarce and temperatures are high during the grain-filling period. The response of 12 cultivated barley (Hordeum vulgare L.) genotypes consisting of 6 breeding lines showing high yield under terminal water stress and 6 commercial varieties was studied in a rain shelter. Trials were performed over 3 years to determine the influence of terminal water stress on yield and yield components and the relationship between yield and phenological and agronomic traits. When the crop reached the flag-leaf stage, half of the experimental plots were subjected to a water-stress treatment and the remainder were maintained at optimal water conditions. Variations were observed in number of days to ear emergence, days to maturity, and length of grain-filling period. Precocity strongly influenced the length of the grain-filling period so that the earlier genotypes had the longest grain-filling periods. Among yield components, mean grain weight had the greatest influence on yield under terminal water stress conditions. Earliness and length of grain-filling period were the phenological traits that most influenced yield in water stress conditions. These traits and harvest index (HI) showed a significant correlation (P < 0.001) with grain yield. Earliness, mean grain weight, and HI contributed to greater yields under terminal water stress.


2021 ◽  
Vol 22 (13) ◽  
pp. 7235
Author(s):  
Md. Tahjib-Ul-Arif ◽  
Mst. Ishrat Zahan ◽  
Md. Masudul Karim ◽  
Shahin Imran ◽  
Charles T. Hunter ◽  
...  

Several recent studies have shown that citric acid/citrate (CA) can confer abiotic stress tolerance to plants. Exogenous CA application leads to improved growth and yield in crop plants under various abiotic stress conditions. Improved physiological outcomes are associated with higher photosynthetic rates, reduced reactive oxygen species, and better osmoregulation. Application of CA also induces antioxidant defense systems, promotes increased chlorophyll content, and affects secondary metabolism to limit plant growth restrictions under stress. In particular, CA has a major impact on relieving heavy metal stress by promoting precipitation, chelation, and sequestration of metal ions. This review summarizes the mechanisms that mediate CA-regulated changes in plants, primarily CA’s involvement in the control of physiological and molecular processes in plants under abiotic stress conditions. We also review genetic engineering strategies for CA-mediated abiotic stress tolerance. Finally, we propose a model to explain how CA’s position in complex metabolic networks involving the biosynthesis of phytohormones, amino acids, signaling molecules, and other secondary metabolites could explain some of its abiotic stress-ameliorating properties. This review summarizes our current understanding of CA-mediated abiotic stress tolerance and highlights areas where additional research is needed.


Sign in / Sign up

Export Citation Format

Share Document