**1. Introduction**

Improving agricultural productivity is the prime goal of farmers around the globe to meet the food demand of the entire population. Over the years, the global population is increasing at alarming rate and likely to increase even further in future. Food scarcity is therefore a major issue which many countries of the world are experiencing now. Rapid industrialization/urbanization, migration of rural people to urban areas for alternative job opportunities, literacy, low agricultural production, lack of policies etc. are key reasons for which agriculture sector is suffering currently. In order to achieve the food security, agricultural production needs to be lifted at

this hour. However, shrinkage of agricultural land in resonance with population growth forces the farmers to go for intensive farming approach. In intensive farming, excessive uses of chemicals and unscientific management practices not only degrade the soil, water and other precious natural resources of the crop production, but also create climate change issue which possess a major threat to sustainable agricultural production. Further, industrialization/urbanization, deforestation or any other anti-nature practices aggravate this climate change situation and thereby, affect crop production.

Performance of a crop relies on the interaction of its genetic traits with the growing environment. Crop plants suffer from climate change scenario due to their sessile growth habit. Climate change exerts various stresses on crop plants and thereby, affects the crop negatively in most cases. Such stresses can be exhibited from the living (biotic) or non-living (abiotic) things of the environment. In nature, various stresses usually put combined impact on the crop plants. Abiotic stresses such as drought, flood, salinity, temperature extremes (hot/cold), heavy metals, light, wind, nutrients/chemicals etc. on plants are either physical or chemical in nature [1]. These abiotic stresses resulted from climate change determine the distribution of plants in different environmental conditions [2] and thereby, influence the crop productivity throughout the globe [3]. These stresses during any crop growth stages specially, reproductive stage markedly reduce yield of the crop by affecting reproductive organs [4]. They are also known to influence biotic stresses positively, which in turn, affect agricultural production through disruption of seed germination, vegetative growth, dry matter production and its partitioning to reproductive parts [5]. Around 70% of yield reduction in the world is due to abiotic stress [6]. Severe stresses not only affect the yield but also seriously hamper the quality of the produce through creating imbalance between demand and supply of nutrients, inactivation of enzymatic activities, suppression of various genes responsible for the quality expression etc. [7]. As these abiotic stresses put barriers on global food security, it is needed to develop suitable strategies to achieve considerable amount of yield with maintained quality under climate change situation.

In this context, seed is a key driver of agriculture. Quality seed production and its utilization can play major roles in achieving high yield under climate change scenario. However, quality seed production under various abiotic stresses needs special emphasis as these stresses exert detrimental effects on plant. Abiotic stresses limit the production and quality by affecting the crop plants from morphological to molecular levels [8]. However, in response to the stresses, plant shows few mechanisms like escaping stress, stress avoidance and stress tolerance. Plant undergoes certain molecular, cellular and physiological changes to cope up with stresses and acclimatizes under stress situation. Insight view to such changes is one of the fundamental components of plant studies to ensure food security. Improved understanding of plant response to stresses can help to develop various strategies to alleviate the stresses. Such strategies include various traditional and modern breeding, agronomic management practices along with exogenous applications of stress tolerating compounds to cope up with abiotic stresses. This chapter highlights the impacts of abiotic stresses on crop plants specially seed production and quality as well as points out various agronomic management strategies to cope up with the abiotic stresses by providing the understanding of plant's defense against such stresses.
