Saddam Hussain

By Umair Ashraf, Saddam Hussain, Alam Sher, Muhammad Abrar, Imran Khan and Shakeel A. Anjum

Weeds are one of the major biological threats to higher rice productivity worldwide. Various cultural, biological, physical and chemical practices affect the composition and intensity of weeds in rice fields. Generally, weeds can be controlled through herbicides; nevertheless, chemical weed control is not a sustainable option on a long term. Various agronomic practices such as the use of tolerant cultivars, adjusting sowing time, tillage permutations and plant geometry may reduce the weed pressure in rice. Integrated approaches for weed management, emphasizing on the combination of management practices and scientific knowledge, may reduce the economic costs and improve weed control owing to the complexity of the weed community. The present chapter reveals the role of planting geometry and herbicides as weed management strategies in rice, and discusses the issue of herbicide resistance associated with chemical weed control. Moreover, the research and knowledge gaps in rice weed management through planting geometry and herbicides were also highlighted.

Part of the book: Grasses as Food and Feed

By Sadam Hussain, Abdul Khaliq, Umer Mehmood, Tauqeer Qadir, Muhammad Saqib, Muhammad Amjed Iqbal and Saddam Hussain

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.

Part of the book: Climate Change and Agriculture

By Attiqa Rahman, Ghadeer M. Albadrani, Ejaz Ahmad Waraich, Tahir Hussain Awan, İlkay Yavaş and Saddam Hussain

Plant secondary metabolites (PSM) are one of the major sources of industrially important products such as food additives due to their distinctive tastes, smells, and flavors. Unlike primary metabolites such as carbohydrates, lipids, and proteins, these secondary chemicals are not involved in plant growth, development, and reproduction but play a significant role in ecosystem functioning. These secondary biochemicals also play a key role in plant communication and defense, particularly under different environmental stresses. Plants may exhibit a defense response to combat these abiotic environmental stressors by generating a variety of PSMs to minimize cell and tissue damage. Secondary metabolites are very diverse (almost more than 200,000) in nature, majorly classified into terpenoids, phenolic compounds, nitrogen, and sulfur-containing secondary metabolites, separated based on biosynthetic pathways (shikimate pathway, mevalonic pathway, and tricarboxylic acid cycle pathway). This chapter summarizes the stimulating effects of different abiotic stressors (heavy metals, cold and high temperature, light, salinity, and drought) on secondary metabolite production. A major focus is given on the synthesis of secondary metabolite and accumulation in plants under stressful conditions, and their role in the regulation of plant defense.

Part of the book: Plant Abiotic Stress Responses and Tolerance Mechanisms