Aphid Dynamics in Relation to Meteorological Factors and Various Management Practices in Bread WheatThe infestation of aphids in wheat is becoming a serious problem nowadays and it might become a threat to the future wheat crop in Pakistan. With this problem in mind we did a study pertaining to aphid dynamics in relation to meteorological factors and various management practices in bread wheat. The study was carried out at the Wheat Research Institute, Faisalabad, Pakistan. The aim of this study was to investigate how meteorological factors play a role in the fluctuating aphid population and how different management practices could be effective in combating aphids. The results revealed that a peak aphid population was recorded during the beginning of the third week of March for both of the study year periods of 2007-2008 and 2008-2009. Aphid density was positively associated with maximum as well as minimum temperature while it showed a negative correlation with relative humidity. However aphid population was positively but not significantly affected by rainfall. Early sowing on 1st November produced the least aphid infestation hence early sowing was encouraged as a cultural practice for keeping aphids below damaging levels. The recently developed wheat varieties like: SHAFAQ-06, SEHER-06, FSD-08 and LASANI-08, revealed aphid resistance and performed better against aphids. On the other hand the genotypes V-05003, BARS-09 and 0BT006, revealed maximum vulnerability to aphids. Number of aphids per tiller was positive correlated with loss in grain yield. Application of insecticide significantly controlled the aphid population which suggested that a combination of host plant resistance with chemical control could restrain the aphid infestation in wheat.

The major wheat-producing countries have heterogeneous and fragile agro climatic surroundings but frequently restraining wheat yield and quality losses are predominant under heat and drought prone agriculture exclusively when both stresses occur in blend, which looms the food security globally. However, many suggested examples are available in these countries for the mitigation of these two stresses by using different conventional and modern improvement and agronomic approaches. In addition to these approaches, morphological, physiological, anatomical, biochemical, phenological, and physiochemical vicissitudes, which trigged during these stresses, have also been elucidated. There complete deliberation in combination for wheat improvement is still a contest, but a win-win option is a holistic attitude in future.

The rust fungi especially emergence of new rust races has serious threat to global wheat production. This is mainly due to the widespread use of race-specific seedling resistance genes and evolution of new virulence races like Yr9, Yr27, and Sr31. Several quantitative disease resistance (QDR) or durable resistance genes i.e. Lr34/Yr18/Pm38/Sr57, Lr46/Yr29/Pm39/Sr58, Lr67/Yr46, Lr68 providing resistance to rust diseases at either high or low temperatures have been identified. But, changing climatic conditions affect the level of resistance in cultivars, as at high temperature Lr34/Yr18 genes which confer durable resistance in wheat become less effective and at low temperature it provides high resistance. While in contrast, yellow rust resistance genes; Yr36 and Yr39 confer resistance at high temperature and later growth stages. This review provides a detailed discussion on, the different aspects of climate change that how it affect host resistance and pathogenic variability and its sustainable control by developing cultivars with high level durable resistance.

Wheat is admired food crop that plays its role in food security in many mounting countries like Pakistan. Although harvesting time and various storage systems exert a major impact on wheat but high temperature and humidity during storage are detrimental for wheat grain health, quality, and germination knack. High storage temperature shoddily affects wheat quality. During safe wheat storage, moisture content should array from 8% to 14%. Refrigeration circumstances are imperative vehicles for the stored wheat grains to obtain utmost germination, quality, and preclusion from insect infestation. To retain better wheat quality, it should be stored below 25°C at 60% relative humidity. Some insects deteriorate wheat germination, damage the grains and cause substantial weight losses but the underlying problem may be effectively overcome with the natural fumes under hermetic conditions which also stimulates germination. Insect control in stored wheat through chemical method has residual effect and is perilous for human health. Practical applications Wheat is the only major food crop that is cultivated in more than 60 countries of the world and 10%–20% of human daily calorie intake is fulfilled by this crop. It is very vital crop for the food security of many developing countries including Pakistan. Although wheat is mainly influenced by harvesting time and storage structures yet other factors such as moisture content, storage temperature, storage humidity, and insect infestation at storage are explained in this review which are detrimental for wheat storage stability, grain health, nutritional quality, and germination knack. Besides this, effect of storage period on grain nutritional quality under various storage facilities is described too. Furthermore, optimum keeping conditions and effective solution to minimize insect damage of stored wheat grain are described in order to ensure national food security and to avoid greater losses in gain quantity, quality, and germination ability.

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