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Drought is considered as one of the major limiting factors affecting growth and productivity of crop plants. It severely affects the morphological and physiological activities of the plants and hampers the seed germination, root proliferation, biomass accumulation and final yield of field crops. Drought stress disrupts the biosynthesis of chlorophyll contents, carotene and decreases photosynthesis in plants. It gradually reduces CO2 assimilation rates owing to decrease in stomatal conductance. In addition, drought affects cell membrane stability and disrupts water relations of a plant by reducing water use efficiency. To cope with these situations, plants adopt different mechanisms such as drought tolerance, avoidance and escape. In this review, we discussed about the effects of drought on morphological and physiological characteristics of plants and suggested the different agronomic practices to overcome the deleterious effects of drought stress.

The study empirically examines the environmental Kuznets curve (EKC) hypotheses by investigating the relationship between ecological footprint, economic growth, energy consumption, and population growth. The study uses ecological footprint as a measurement of environmental degradation which is a more comprehensive indicator and considers all factors responsible for environmental degradation. Keeping in view the problem of cross-sectional dependence, a more efficient estimation tools like pooled mean group and augmented mean group have been used to estimate the long-run parameters for 22 European countries from 1995 through 2015. Results of the study found a quadratic relationship between income growth and ecological footprint and support validity of EKC. Energy consumption positively contributes to ecological footprint, while population growth plays no significant role in determining environmental quality. The long-run estimates of the study are validated through robustness analysis by employing dynamic ordinary least square (DOLS) and fully modified ordinary least square (FMOLS) techniques. Dumitrescu and Hurlin (2012) panel non-causality test indicated that there is a unidirectional causality running from GDP to ecological footprint while bidirectional causality running between energy consumption and ecological footprint. The study identified that population growth in European region is not a severe issue as compared to intensive energy consumption. Policies which restrict emission, deforestation, and water pollution should be adopted for sustainability of environment.

Sugarcane is an important crop for bioenergy and sugar, contributing to Gross Domestic Product (GDP) of Pakistan. Global warming and increasing greenhouse gas emission result in the increased intensity and frequency of extreme weather events. Temperature stress is a major environmental stress that limits the sugarcane growth, productivity and metabolism worldwide. Numerous biochemical reactions are involved in plant development, and these biochemical reactions are very sensitive to temperature stress. Now a day, temperature stress is a major concern for sugarcane production and approaches for high yield of sugarcane under temperature stress are important agriculture goals. Sugarcane plant adapts a number of acclimation and avoidance mechanism against different environmental stress. Plant survival under different stresses depends on ability to generate and transmit the signal and biochemical and physiological changes. In future, climate change is an important consequence for sugarcane production in the world because of its relative low adaptive capacity, poor forecasting system and high vulnerable to natural hazard. In this review we briefly describe climate change effects on sugarcane, sugar production in several countries especially in Pakistan, future challenges for sugar production under changing climatic scenario and propose strategies for mitigation negative impacts of climate change.

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Salinization of soils is a major impediment to their optimal utilization in many arid and semi-arid regions throughout the world. In several large irrigation schemes, salinity-induced land degradation has increased steadily over the last few decades with concurrent reductions in agricultural productivity and sustainability. Currently, saline soils occur within at least 100 countries. These soils need explicit approaches in their amelioration since soil salinization cannot be reduced by routine irrigation and crop management practices. The approaches used to ameliorate saline soils can be broadly divided into four major categories: (1) leaching of bare saline soils to move excess soluble salts from upper to lower soil depths or out of soil profile in the presence of a natural or artificial drainage system; (2) leaching of cropped saline soils with certain plant species, which can withstand ambient salinity levels; (3) surface flushing or mechanical removal of salts from soils that contain salt crusts at the surface or where drainage is inadequate and leaching is restricted by the presence of a shallow water table or highly impermeable profile; and (4) reduction of salts from saline soils through biological means - the harvest and removal of high-salt accumulating aerial plant parts - in areas with negligible irrigation water or rainfall for leaching. Research and practice have shown that in the presence of a drainage system, saline soils can be brought back to a highly productive state by leaching the excess soluble salts from the effective rooting depth. Among the amelioration methods, cropping in conjunction with leaching has an advantage; cropping during or between leaching events increases salt removal efficiency because of a decrease in soil-water content under unsaturated water flow conditions with a concurrent decrease in large pore bypass and drainage volume. However, anaerobic conditions in soil may occur during leaching of cropped soils, thereby affecting growth of those plant species that are sensitive to such conditions. Thus, in addition to existing salt-resistant plant species, research is needed to explore or develop genotypes that can withstand the twin stresses of salinity and hypoxia. Although significant efforts have been made to develop models for simulating movement and reactions of salts in saline soils during the amelioration process, these models need evaluation and verification under actual field conditions.