Development Of Crop Species Research Articles

The ameliorative effects of exogenously applied proline on physiological and biochemical parameters of wheat (Triticum aestivum L.) crop under copper stress condition

ABSTRACTThe presence of significant amount of heavy metals in rivers and canals due to mixing of untreated industrial effluents is a common phenomenon, especially in developing countries. The agricultural crops are influenced by the presence of various pollutants in the sewage, being applied for irrigation purpose. The effluents containing copper affect the growth and development of crop species, thereby, ought to be mitigated by foliar spray of osmoprotectants, e.g. proline. A pot culture experiment was conducted at the University of Agriculture, Faisalabad-Pakistan during the crop season 2015–2016. The treatments consisted of (a) three wheat varieties (Punjab-96, MH-97, FSD-83), (b) two levels of copper (0, 400 µM) applied through rooting medium, and (c) two levels of proline (0, 80 mM) applied through foliar application. The treatments were arranged in a completely randomized design with four replications. The results showed that application of 400 µM copper caused a reduction in biomass accumulation, chlorophyll (‘a’ and ‘b’) contents, and eventually yield (100-grain weight). There were also significant decreases in gas exchange parameters (stomatal conductance, internal CO2 concentration), photosynthetic rate, water-use-efficiency, and transpiration rate in response to copper stress. Metal toxicity caused the maximum reduction in productivity of PSII, electron transport rate, and photochemical quenching, while higher values of non-photochemical quenching were recorded in the wheat varieties. The activities of antioxidant enzymes (superoxide dismutase, catalase, peroxidase), as well as quantities of proline, protein and calcium contents were accelerated in response to copper stress. The uptake of calcium, magnesium, and potassium constituents by plants was reduced, while assimilation of calcium was increased in plants under copper stress. However, the occurrence of negative effects on these parameters due to copper stress was mitigated by foliar spray of proline at the rate of 80 mM solution. The exogenous application of proline at the rate of 80 mM resulted in the reduction of generation of reactive oxygen species and enhanced accumulation of proline and protein contents in wheat varieties under copper stress environment.

Evidence of the Interaction Between Crop Species and Organic Amendments: Modelling of the Differential Grain Yield Response of Wheat, Soybean, and Canola to Organic Amendments

<p>Knowledge on the interaction between plants and organic amendments is critical for the basic understanding of agroecosystems sustainability. Organic amendments are of great interest in agriculture by virtue of their ability to restore lost soil organic carbon in eroded or conventionally cultivated soils. The major objective of this study was to demonstrate and model the differential response of crop species to organic amendments. Despite the potential of such an interaction to improve crop production, it has never been formally demonstrated in a planned experiment. A two-year greenhouse experiment set as 3×3×5 factorial in a strip-split plot design was conducted. The effects of crop species, type of organic amendment, and application rates on grain yield of soybean, canola, and wheat were evaluated. To account for the asymmetry of the concave responses of soybean, mathematical transcendental models were fitted, for the first time, to yield data.<em> </em>The interaction between crop species and amended soils was highly significant. Soybean displayed concave transcendental yield responses whereas canola and wheat exhibited negative exponential responses, irrespective of the type of amendment. Turkey compost outperformed turkey litter and beef manure by 30% and 52%, respectively, with respect to soybean production; whereas turkey litter outperformed turkey compost and beef manure by 144% and 264%, respectively, with respect to canola and wheat production. It is concluded that in greenhouse settings and perhaps field conditions, growth and development of crop species can be enhanced by matching the specific characteristics of organic amendments to the specific nutrients demand of crop species.</p>