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1.
Salinity is a major abiotic stress that affects crop production throughout the world. Biochar is an activated carbon soil conditioner that can alleviate the negative impacts of salinity. The research was conducted to evaluate the ameliorative effect of 1% and 2% of biochar application on wheat seed germination and growth attributes under salinity. Both levels of biochar improved the germination and growth conditions under salinity; however, 2% biochar level was more effective compared to 1% level. Root and shoot length increased up to 23% and11% with 2% biochar, respectively. The maximum increase of 16% and 10% in leaf water potential and osmotic potential was noted with 2% biochar at 150 mM salt. The decrease in proline content and soluble sugar at 2% biochar was 51% and 27%, respectively. Decrease in superoxide dismutase activity was 15.3% at 2% level of biochar under stress biochar mitigates the negative effects of salinity and improved wheat productivity.  相似文献   
2.
The zinc (Zn) requirement of a maize (Zea mays L.) hybrid (‘FHY-396’) and an indigenous variety (‘EV-7004’) was measured at low (22.4 ± 5°C) and high (28.8 ± 5°C) root-zone temperatures (RZT). Four Zn rates (0, 3, 9 and 27 mg kg?1 soil) were applied to a calcareous loam soil in pots for the glasshouse study. Shoot and root dry matter yields were significantly more at the higher RZT. Regardless the RZT, maximum relative shoot dry matter yield in hybrid and variety was produced, respectively, at 9 and 3 mg Zn kg?1 soil. Zinc concentration in roots and shoots of both the cultivars increased with Zn rates and it was significantly more at the higher RZT. Cultivars differed in critical Zn concentration (CZnC) required for maximum shoot dry matter yield. The CZnC ranged from 25 to 39 μg Zn g?1 plant tissue for optimum growth of both the cultivars at low and high RZT.  相似文献   
3.
Under the umbrella of WTO, the reduction in trade barriers has forced the policy makers to focus on the export competitiveness. Rice is an important source for foreign exchange earnings for the economy of Pakistan, keeping in mind of this fact, the competitiveness of Pakistan’s rice with other major exporters was examined by applying revealed competitive advantage. The domestic consumption trends of rice among the major rice exporting countries were also analyzed in the current study. The results revealed that as compare to other major exporters of rice in the world, Pakistan had high competitive and comparative advantage in the production of rice. The comparison of the movements in comparative advantage indices for Pakistan with the major world rice competitors/exporters showed that Pakistan possessed relatively high comparative and competitive advantages in rice production. The declining domestic per capita consumption of rice and increasing trends in competitiveness for Pakistan clearly revealed the expected potential of higher growth which meant that rice exports from Pakistan could continue to play an important role for the earnings of foreign exchange. In order to exploit the potential benefits of rice exports, we need to strengthen the competitiveness in rice sector of Pakistan.  相似文献   
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Tropical Animal Health and Production - Alpha-lactalbumin has been reported as a highly polymorphic gene that potentially alters the gene expression and is associated with milk composition in dairy...  相似文献   
6.
Leaf anatomical changes were appraised in exogenously applied trehalose of radish (Raphanus sativus L.) plants grown under nonstress (well-watered) and water stress (60% field capacity) conditions. Two cultivars of radish namely, Manu and 40-Day, were grown in a pot experiment at the Botanical Garden, GCUF, Pakistan. Plants were subjected to 60% field capacity conditions after three weeks of germination. Trehalose (25 mM) was applied to the radish plants through two different modes (foliar and presowing). After 2 weeks of foliar-applied trehalose, the leaves were excised from the plants for studying different anatomical features. Water stress caused a significant reduction in the leaf vascular bundle area, leaf midrib thickness (only in cv. Manu), leaf parenchyma cell area, and the number of vascular bundles in both radish cultivars, while water stress increased leaf epidermis thickness of both radish cultivars. Exogenously applied trehalose through both (presoaking and foliar spray) modes was effective in increasing leaf epidermis thickness, vascular bundle area, midrib thickness, and number of vascular bundles in both radish cultivars under water stress and nonstress conditions. Foliar-applied trehalose was more effective in increasing midrib thickness in both radish cultivars under both water regimes. Of both cultivars, the performance of cv. Manu was better in leaf epidermis thickness, leaf midrib thickness, vascular bundle area, leaf parenchyma cell area, and the number of vascular bundles. Overall, exogenous application of trehalose through both modes was effective in triggering leaf anatomical changes under different water regimes.  相似文献   
7.
Luteoviruses are economically important plant viruses. Specifically, barley yellow dwarf virus is epiphytotic to almost all small-grain cereal growing areas. The disease cycle is complex. This luteovirus has evolved several intelligent mechanisms to communicate with both plant and phloem-feeding insect-vector aphid. Environmental cues influence disease severity, aphid infestation and viral load. Within an aphid, virus circulates persistently in a non-propagative manner and is transmitted selectively to the host plants. Selection of viruses within aphids has a role in virus isolate prevalence over a specific area. In the host-plant system, the virus has to release its single sense-strand RNA genome (approx. 5.6 to 6 kb), translate and subsequently replicate its genome using its own replicase and host machinery. This review summarizes our current understanding of disease epidemiology and reviews the current literature encompassing viral infectivity, economic impact and control measures.  相似文献   
8.
Fish Physiology and Biochemistry - Three trials were conducted to evaluate the performances of red snapper, Lutjanus campechanus, in low salinities. The median lethal concentration (96 h...  相似文献   
9.
Among various abiotic stresses, global drought reduces global growth and yield of wheat. Present research has been designed to ameliorate the adverse effects of drought stress on wheat by combined application of plant growth-promoting rhizobacteria (PGPR), compost, and mineral fertilizers. In this experiment, the role of fertilizer, compost, and PGPR inoculation to ameliorate drought stress was studied in two wheat varieties at vegetative stage. Water stress adversely affects morphology, physiology, and biochemistry of the wheat plant. Inoculated seed with compost and mineral fertilizer grown in drought condition showed 43% increase in relative water content (RWC) of 9.39% in Membrane Stability Index and 82.20% in chlorophyll as compared to control. Drought affected the accumulation of osmolytes, but PGPR in combination with compost and mineral fertilizer under drought stress triggered higher accumulation of soluble sugar and proline content, i.e., 28.96% and 73.91%, respectively. It is concluded from this research that PGPR in combination with compost and mineral fertilizer considerably reduces the effect of drought on wheat by enhancing the physiological (RWC, membrane stability, chlorophyll content, and water potential) and biochemical (proline and sugar) aspects of the plant.  相似文献   
10.
ABSTRACT

The knowledge about heterosis breeding of achene yield in sunflower is known; however, dissection of the genetic components of achene yield and seed quality traits is limited. Therefore, the prescribe study was conducted using Line × Tester design to determine combining abilities, and about the maternal-and-paternal gene actions involved in achene yield and seed quality traits in 21 single cross hybrids. Significant mean differences for achene yield and seed quality traits were observed, with total attributed variation (R2?=?0.89). Principal component analysis (P?<?0.05) explained 92.6% variation and using factor analysis, we found factor 1 had primary variables (AW, AL, AT, HD, PH, PC, LA and OC) contributed 35.6% variation to achene yield. Combining ability analysis showed the positive general combining ability for E%, HD, PH, 100 AW and AYP in parental inbred lines, whilst, hybrids had positive specific combining ability for E%, HD, PH, 100 AW, DTF, DTM, OA, LA, OC and AYP. Females contributed significantly higher (P?<?0.05) for AYP, E%, HD, NWPH, PH, 100 AW, LA and OA than that of males. Two-way hierarchical clustering showed the most promising hybrid H5 (A-18?×?G-79) in Cluster V. The hybrid H5 also showed heterosis, heterobeltosis and commercial heterosis, therefore, genetic exploitation of H5 is highly desirable in future breeding to map QTLs/genes in arid/semi-arid zones and /or similar growing conditions to boost up yield and seed quality traits.  相似文献   
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