Essay: Factors that affect crops

It is known truth that growth and productivity nutrients contents of oil seed crops significantly affected by different environmental dynamics. The deficiency of water is well thought out one of the most important factors among these different critical environmental conditions that changes the yield parameters and reserve oil content in crops (Ali et al., 2010).
Proline content increased in the tissues is the principal symptom under abiotic stress in plants. Drought and salinity along with temperature also cause osmotic stress (Simon-Sarkadi et al., 2006).
There is significant variation in cotton production in Pakistan from last thirty years in line for huge number increase in pests bothers, diseases and more important is the deficiency of water for irrigation under developmental and reproductive stages of growth. The simple trend of reduction of available water for irrigation is 13.4 percent in last 30-40 years (Anon., 2013).
The secondary antioxidant compounds such as phenols, flavonoids, tocopherols and carotenoids obtained from oil. The oil oxidative stability is maintained in cell by these antioxidants. Even though these compounds have no nutritious value, they are essential for human health because of their antioxidative and bioactive properties (Ali and Ashraf, 2011).
The exogenous use of proline as foliar application has reported in many experiments showed significant role in improving plant tolerance under abiotic stressed condition. This deteriorating effect of proline application can make it osmoprotectant (Ali et al., 2007) and protection against ROS (Banu et al., 2009).
By increasing the activities of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) together with Proline protects cellular and subcellular membranes from oxidative stress, this protective effect of foliarly applied proline showed due to stabilization of plasma membrane (Islam, 2009).
Drought is the major abiotic stresses which worldwide affect and lessens the yield and productivity of food crops up to 70% (Akram et al., 2013).