Moazzam Jamil

Potassium applied under drought improves physiological and nutrient uptake performances of wheat (Triticum Aestivun L.)

The physiological and nutrient uptake performance of two wheat (Triticum aestivum L.) cultivars (Lasani-2008 and Auqab-2000) to foliar application of 1% potassium (K) at three different growth stages (tillering, flower initiation and grain filling) was investigated under water limited environment in a wire house experiment at the Nuclear Institute for Agriculture and Biology, Faisalabad. The aim was to find out the best K application stage for improvement in drought tolerance potential. Drought stress was created by withholding irrigation at the three growth stages and then K was sprayed with carboxymethyl cellulose as a sticking agent, whereas Tween-20 was used as a surfactant for foliar spray. At maturity, aboveground nitrogen, phosphorus, K, sodium and calcium uptakes by the crop were measured. Besides, water potential, osmotic potential and turgor potential of crop were also estimated. The results indicated that the drought stress at all three critical growth stages of wheat adversely affected plants nutrient uptake, water potential, osmotic potential and turgor potential of wheat plants. The exogenous application of K under drought stress at all three critical growth stages enhanced tolerance of wheat by reducing toxic nutrients uptake and improving the physiological efficiency. In this regards, both varieties showed uniform behavior. Maximum improvement in all the recorded nutrients uptake and physiological parameters was achieved when K was applied at grain filling stage of both cultivars.

Paclobutrazol Soil Drenching Suppresses Vegetative Growth, Reduces Malformation, and Increases Production in Mango

Emergence of unproductive vegetative shoots/flushes is considered to be a main cause of low yield, irregular bearing, and malformation of inflorescences in mango. Selected mango trees of the cultivars ‘Chaunsa’, ‘Dushehare’, and ‘Anwar Ratool’ growing in the subtropical region of Khanewal (30°18′0N, 71°56′0E), a district of Pakistan, were characterized as having excessive vegetative growth, erratic flowering, and fruiting with declining productivity due to malformation of inflorescences. Paclobutrazol soil drenching was evaluated as a method to suppress excessive vegetative growth and to increase the number of reproductive shoots even during the ‘off’ season. Different rates of paclobutrazol was applied at rates of (0, 2, 4, 6, 8, 10, and 12 g a.i.) in September through soil drenching. Results showed that soil drenching with paclobutrazol at the highest rates (12, 10, and 8 g a.i.) was significantly effective in suppressing vegetative growth, reducing the increase in canopy volume, and flush length as compared to control trees in all treated cultivars of mango. Statistically significant differences were recorded in treated trees as compared to control regarding the emergence of reproductive shoots, fruit setting, panicle length, fruit drop, intensity of emergence of malformed panicles, and yield. Response of selected cultivars of mango to paclobutrazol was statistically different regarding various vegetative and reproductive growth characteristics. Paclobutrazol was more useful in ‘Seasonal Chaunsa’ as compared to ‘Dushehare’ and ‘Anwar Ratool’ for improving various vegetative and reproductive parameters studied in this research.

Nitrogen application improves gas exchange characteristics and chlorophyll fluorescence in maize hybrids under salinity conditions

The understanding of crop physiological responses to salinity stress is of paramount importance for selection of genotypes with improved tolerance to this stress. Maize (Zea mays L.) hybrids Pioneer 32B33 and Dekalb 979 were grown in pots and subjected to three levels of salinity under four nitrogen levels to determine the role of nitrogen under saline conditions. Salinity stress effects on gas exchange characteristics and chlorophyll fluorescence of maize hybrids were evaluated under semi-controlled conditions. Under salinity stress, the changes in the net photosynthetic rate (PN), stomatal conductance (gs), and transpiration rate (E) were similarly directed: all decreased and were lower than in control at the higher salinity level (10 dS/m). Water use efficiency was increased with increasing salinity since transpiration was stronger depressed by salt than photosynthesis. Plants subjected to the lower level of salinity did not differ from control in tested characteristics. Nitrogen application ameliorated the effects of salinity.

Agrochemicals and Soil Microbes: Interaction for Soil Health

To fulfill food and fiber demand of the ever-increasing population over the world, agrochemicals are being used in large quantities. These agrochemicals include chemicals (hormone, fungicide, or insecticide, pesticides, and fertilizers) manufactured or processed for agricultural use to increase crop yield for economic point of view. Soil microbes constitute the biosphere that is the most important fraction of soil involved in nutrient cycling thus maintaining soil fertility. Agrochemicals are used to enhance the productivity of crops but when entering into soil directly affect soil microbes which ultimately deteriorate soil health. Many biological functions of the soil are disrupted by the application of agrochemicals. The direct and indirect effects of these chemicals on soil biology are reduction in population, proliferation of beneficial soil microorganisms and their biotransformation, decrease in biological nitrogen fixation, and reduced mineralization of organic compounds. Soil microbial enzymatic activities are the indicators of soil biological health, fertility, and chemical status. Agrochemicals incorporated in the soil eradicate beneficial soil microbes which are involved in important enzymatic components like chain of reactions that play vital role in synchronizing important chemical processes in soil. On the other hand, many microbes in the soil have the ability to degrade or metabolize the agrochemical pollutants in the soil to ensure the soil health. Soil microorganisms have intrinsic nature for rapid degradation processes and genetic adaptation to chemicals in the environment. Agrochemicals of diverse nature could be remediated from soil and water with the use of potential microorganisms in the soil. In this chapter, the effect of agrochemicals on soil biology and the role of soil microbes in the degradation of agrochemicals have been reviewed and summarized.

Biochemical diversity in wild and cultivated pomegranate (Punica granatum L.) in Pakistan

ABSTRACT The present study was conducted to screen out elite pomegranates through determination of biochemical diversity in wild and cultivated genotypes for a breeding program and for fresh/processed use in industry. The results showed high morphological diversity in accessions of wild pomegranate fruits as compared to cultivated genotypes. The first six principal components covered 80.75 and 75.49% diversity in 53 wild and 62 cultivated pomegranate genotypes, respectively. High values of the coefficient of variance (10.78–18.62%), and a high range of minimum to maximum values of total soluble solids, titratable acidity, ascorbic acid content, total soluble sugars, and total phenolic content (0.10–1.25, 5.88–29.96, 9.69–19.85 and 175.05–595.42), respectively, were recorded in the studied genotypes. Ascorbic acid content had a strong correlation with antioxidant activity (0.952%), super dismutase oxides (0.94%), catalase (0.921%), and titratable acidity (0.91%). Peroxides had a strong correlation (0.88%) with catalase, and 0.81% each with super dismutase oxides and antioxidant activity. Wild and cultivated pomegranates were clustered successfully in separate groups, based on biochemical traits. A variety improvement program and selection of high-quality pomegranate genotypes could help to reduce pomegranate-related malnutrition issues in the human diet.

Preliminary study on phosphate solubilizing Bacillus subtilis strain Q3 and Paenibacillus sp. strain Q6 for improving cotton growth under alkaline conditions

Background Low phosphorus availability limits crop production in alkaline calcareous soils in semi-arid regions including Pakistan. Phosphate solubilizing bacteria may improve crop growth on alkaline calcareous soils due to their ability to enhance P availability. Methods Twenty rhizobacterial isolates (Q1–Q20) were isolated from rhizosphere of cotton and characterized for their growth promoting attributes in vitro. The selected phosphate solubilizing isolates were further screened for their ability to improve cotton growth under axenic conditions (jar trial). The phosphorus solubilization capacities of selected strains were quantified and these strains were identified through 16S rDNA sequencing. Results Isolates Q2, Q3, Q6, Q7, Q8, Q13 and Q14 were able to solubilize phosphate from insoluble sources. Most of these isolates also possessed other traits including catalase activity and ammonia production. The growth promotion assay showed that Q3 was significantly better than most of the other isolates followed by Q6. Maximum root colonization (4.34 × 106 cfu g−1) was observed in case of isolate Q6 followed by Q3. The phosphorus solubilization capacities of these strains were quantified, showing a maximum phosphorus solubilization by Q3 (optical density 2.605 ± 0.06) followed by the Q6 strain. The strain Q3 was identified as Bacillus subtilis (accession # KX788864) and Q6 as Paenibacillus sp. (accession # KX788865) through 16S rDNA sequencing. Discussion The bacterial isolates varied in their abilities for different growth promoting traits. The selected PGPR Bacillus subtilis strain Q3 and Paenibacillus sp. strain Q6 have multifarious growth promoting traits including ability to grow at higher EC and pH levels, and phosphorus solubilizing ability. These strains can efficiently colonize cotton roots under salt affected soils and help plants in phosphorus nutrition. It is concluded that both strains are potential candidates for promoting cotton growth under alkaline conditions, however further investigation is required to determine their potential for field application.

Zinc Solubilizing Bacteria for Zinc Biofortification in Cereals: A Step Toward Sustainable Nutritional Security

Food production and security for the ever-increasing population are becoming a key challenge for the scientists. The food security demands not only enhanced agricultural productivity but also improvement in produce quality while reducing adverse impact of agricultural practices on natural resources and the environment. Inadequate nutrition is popular among poor community. Malnutrition of micronutrients is also common due to less concentration present in food. The concentration of micronutrients is very low in cereals due to dependence on cereals; we are taking micronutrients far below the required ones in daily nutrition and are suffering the deficiency of these micronutrients. Among these, Zn is a part of enzymes that regulates the rate of metabolic reactions involved in the development and growth of crop plants and human beings. Zinc deficiency is a common issue not only in plants but in human being and animals as well. Approximately one third of total population of poor world is at high risk of Zn deficiency because they rely on cereals for their daily caloric intake. Its deficiency is a global problem for plants and can be found in every part of the world. More than 70% of Pakistani soils are zinc deficient. So, the cereal crops grown on these soils are zinc deficient. Zn deficiency is the largest cause of death and diseases in humans. This situation demands some effective strategies to overcome Zn deficiency in edible crops, to enhance the grain Zn content and to minimize adverse effects of Zn deficiency on humans thus reducing malnutrition. Many strategies are available to overcome the zinc deficiency in plants and human beings as well. Most important and sustainable strategy is the use of zinc solubilizing bacteria. Zinc solubilizing bacteria alone or with organic materials may also increase the bioavailability of native and applied zinc to the plants through different mechanisms of actions. In this chapter, importance of zinc with a special reference to zinc solubilizing bacteria and their mechanisms of action for improving the yield and quality of cereals to achieve the nutritional food security has been discussed in detail.

Effect of biochar and quicklime on growth of wheat and physicochemical properties of Ultisols

Acidity of soils poses numerous drastic impacts on physical and chemical properties of soils along with diminishing the soil nutrient status. A pot experiment was conducted to improve the soil physicochemical properties and wheat production in strongly acidic soils (Ultisols) of tropical and subtropical regions of China. Sludge biochar (C1), straw biochar (C2), and quicklime (CaO) were applied in different combinations in the soil, and wheat was grown till maturity. The results revealed that at 4% C1 + 100% CaO, soil pH was amplified by 64%, while exchangeable H+ and Al3+ contents reduced significantly at C1 treatment with and without lime application (p˂0. 05). A significant reduction of 18 and 17% in soil bulk density was observed at 4% C2 and 4% C2 + 50% CaO, respectively. Soil surface cracks in terms of crack area and crack length at 2% C1 + 50% CaO were reduced by 33 and 29%, respectively. Tensile strength of red soil decreased with the addition of amendments and the highest decrease (31%) in tensile strength was observed at 4% C1 + 50% CaO. Shear strength tests exposed that biochar and lime treatments showed slight enhancement (15%) in the internal friction angle (φ) at 2% C1 + 100% CaO and decreased (83.31 and 84.22%) the cohesion (c) value at 2 and 4% C1 in combination with a 50% CaO. The amendments in combination significantly increased the wheat biomass and wheat grain yield (103 and 131%), respectively, at 4% C2 + 100% CaO as compared to the control. The recent study suggests that biochar as well as lime can be effective to improve the physicochemical properties of red soils and wheat yield.

Evaluation of Different Brinjal (Solanum melongena L.) Varieties for Yield Performance and Sucking Insect Pests in Bahawalpur, Pakistan

This study investigated the relative performance of ten brinjal ( Solamum melongena L.) varieties for yield in fall 2014 in Bahawalpur. The study was conducted at farm area of Islamia University of Bahawalpur. Ten brinjal varieties were evaluated for yield performance in a research trial following randomized complete block design. Significant differences existed in the yield generated by tested varieties. Significantly more yield was recorded in Shamli and Eggplant deep black followed by Advanta 306, Sandhya F1, Black boy, Black nagina and Advanta 305 in descending order. Twinkle star and Kalash F1 generated significantly less yield while the significantly least yield was recorded for Xingchangjishi than all the tested varieties. Whitefly Bemesia tabaci (Homoptera: Aleyrodidae) and jassid Amrasca biguttula biguttula (Homoptera: Cicadellidae) were the major sucking insects attacking this crop. Populations of both pest insects were recorded significantly more on Xingchangjishi while least populations of these pests were recorded on Egg plant deep black and Sandhya F1. Correlation of insect populations with yield showed inverse relationships. These results are important regarding varietal performance for yield test conducted for ten brinjal varieties. Varieties i.e., Eggplant deep black and Shamli with significantly more yields are recommended for cultivation in this area to get more brinjal yield.