Question

Crop production under nutrient and moisture stress condition

Answer 1

Drought The initial effect of drought on the plants is the poor germination and impaired seedling establishment. Various studies have reported the negative impacts of drought stress on germination and seedling growth (Kaya et al., 2006; Farooq et al., 2009b). The reduction in germination potential, early seedling growth, root and shoot dry weight, hypocotyl length, and vegetative growth have been reported in important field crops including, pea (Pisum sativum L.), alfalfa (Medicago sativa L.), and rice (Oryza sativa L.) under drought stress (Okcu et al., 2005; Manikavelu et al., 2006; Zeid and Shedeed, 2006).
Heat Stress Under the tropical climates the excessive radiations and elevated temperatures are another major limiting factor to plant growth and development. High temperatures may cause scorching of the twigs and leaves along with visual symptoms of sunburn, leaves senescence, growth inhibition and discoloration of fruits and leaves (Ismail and Hall, 1999; Vollenweider and Gunthardt-Goerg, 2005).
The systems that regulate plant adaptation to water stress through a sophisticated regulatory network are the subject of the current review. Molecular mechanisms that plants use to increase stress tolerance, maintain appropriate hormone homeostasis and responses and prevent excess light damage,

Answer 2

Abiotic stresses are one of the major constraints to crop production and food security worldwide. The situation has aggravated due to the drastic and rapid changes in global climate. Heat and drought are undoubtedly the two most important stresses having huge impact on growth and productivity of the crops. It is very important to understand the physiological, biochemical, and ecological interventions related to these stresses for better management. A wide range of plant responses to these stresses could be generalized into morphological, physiological, and biochemical responses. Interestingly, this review provides a detailed account of plant responses to heat and drought stresses with special focus on highlighting the commonalities and differences. Crop growth and yields are negatively affected by sub-optimal water supply and abnormal temperatures due to physical damages, physiological disruptions, and biochemical changes. Both these stresses have multi-lateral impacts and therefore, complex in mechanistic action. A better understanding of plant responses to these stresses has pragmatic implication for remedies and management. A comprehensive account of conventional as well as modern approaches to deal with heat and drought stresses have also been presented here. A side-by-side critical discussion on salient responses and management strategies for these two important abiotic stresses provides a unique insight into the phenomena. A holistic approach taking into account the different management options to deal with heat and drought stress simultaneously could be a win-win approach in future.