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Salinity stress is a major threat to cotton growth and productivity worldwide. This study evaluated a diverse collection of fifty cotton genotypes at critical seedling stage using analysis of variance and principal component analysis. The seedlings were subjected to 10dSm-1 and 17dSm-1 salt stress levels starting from the 10th day after sowing until the 42nd days. Data was collected on morphological (root length, shoot length, fresh and dry weights of root and shoot, fresh and dry weight of whole plant) and biochemical (K+, Na+, K+/Na+) parameters. Significant variations were observed among the cotton genotypes for the evaluated traits under control and salt stress conditions. The results revealed that salinity stress had detrimental effects on various growth parameters, including root length, shoot length, fresh root weight, fresh shoot weight, dry shoot weight, dry root weight, and whole plant dry weight. Additionally, sodium levels exhibited a substantial increase under NaCl-induced stress, whereas potassium levels experienced reductions in the leaves. Based on multivariate analysis, the genotypes NIAB - 545, FH- Kehkshan, FH-490, and GH-Mubarak displayed notable salt tolerance likely due to mechanisms such as ion exclusion, osmotic adjustment and tissue tolerance at both 10 dSm-1 and 17 dSm-1 levels. Conversely, the genotypes FH-303, FH-532, FH-542, and SB-149 were deemed salt-sensitive. These findings underscore the challenges associated with selection for salt tolerance in cotton due to the potential masking effects of environmental factors on genetic expression. This study discovers potential salt-tolerant cotton genotypes for use in breeding programs to increase yields under saline stress. However, all genotype-environment interactions must be explored. Overall, these findings provide useful information about salt stress responses in cotton seedlings. [ABSTRACT FROM AUTHOR]

The tillering phase of wheat (Triticum aestivum) crops is extremely susceptible to drought. We explored the potential of silver nanoparticles (AgNPs) in protecting wheat genotypes from drought injury during this sensitive stage. After treating with AgNPs (60 ppm), the plants were submitted to different water levels; i.e. 100% field capacity (FC), 75% FC (mild drought), 50% FC (moderate drought) and 25% FC (severe drought) from 15 to 41 days after sowing (tillering phase). Leaf physiological data were collected at stress termination, while yield attributes were recorded at crop maturity. We found that increasing drought intensity significantly impaired leaf physiology and grain yield of both studied genotypes. Compared with control, moderately and severely drought-stressed plants produced 25% and 45% lesser grain yield per spike, respectively (averaged across genotypes and years of study). Likewise, moderate and severe drought reduced photosynthesis by 49% and 76%, respectively, compared with control. In contrast, AgNPs significantly restored leaf physiological functioning and grain yield formation at maturity. For example, under moderate and severe drought, AgNPs-treated plants produced 22% and 17% more grains per plant, respectively, than their respective water-treated plants. Our study suggests that exogenous AgNPs can protect wheat crops from drought during early development stages. Wheat (Triticum aestivum) crops suffer significant grain yield losses when water supplies are affected during the early developmental phases. This study shows varying levels of drought stress impaired carbon assimilation, tiller formation and final grain yield of wheat genotypes. In contrast, exogenously applied silver nanoparticles (AgNPs) restored plant growth and grain yield formation, suggesting their potential to protect wheat crops from drought-induced injury. [ABSTRACT FROM AUTHOR]

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Wheat crops are highly sensitive to high temperatures during reproductive and grain filling phases. This study explored how hydrogen peroxide (H2O2) protects grain yield formation in wheat crops exposed to heat during different developmental phases. Two wheat genotypes, Ujala-16 and Anaj-17, of varying heat tolerances, were subjected to heat stress (32 °C/20 °C) at pre-anthesis, anthesis, and post-anthesis stages under glasshouse and field conditions. Before heat stress treatment, the plants were sprayed with 60-ppm hydrogen peroxide (H2O2). Post-stress changes in leaf physiology were studied to understand the heat recovery mechanism. Despite significant genotypic variations, high temperature damaged leaf physiology and grain yield of both studied wheat genotypes. On average, high temperatures during any developmental phase caused more damage to Anaj-17 than to Ujala-16. Compared with the control, the plants heated during pre-anthesis, anthesis, and post-anthesis produced 44%, 35%, and 25% lesser grains yield per spike (averaged across genotypes and experiments), respectively. In contrast, post-anthesis-stressed plants produced the smallest grains compared to those heated during pre-anthesis or at anthesis. Compared with the control, H2O2-treated plants sustained significantly higher leaf chlorophyll and net photosynthetic rate by protecting cellular membranes from heat injury. Under hot conditions, hydrogen peroxide-treated plants yielded 17% more grains (averaged across the developmental phases and genotypes) than control plants. Our study suggests wheat performance can be improved through exogenous H2O2 application, particularly during terminal heat stress. [ABSTRACT FROM AUTHOR]

Wheat crops are highly sensitive to high temperatures during their reproductive and grain-filling phases. We hypothesized that potassium could increase thermotolerance in wheat during grain filling by protecting cellular organelles, particularly chlorophyll, from heat injury. Two wheat genotypes, Ujala-16 (relatively heat tolerant) and Anaj-17 (relatively susceptible) were grown in pots and were submitted to 4 and 8 days of heat stress under polythene sheets 1 week after anthesis. One day before the onset of heat stress, 2% potassium (K) as K2SO4 was sprayed on all the plants. Flag leaves from both genotypes were collected after 4 and 8 days of heat stress. Leaf physiology changes were measured to quantify heat damage and to understand the K-induced recovery mechanism. The crop was harvested 125 days after sowing, and grain yield data were collected. Increasing duration of heat stress significantly impaired leaf physiology and grain yield of both studied wheat genotypes. Compared with control (under optimum temperature), 4 and 8 days heat-stressed plants produced 11 and 19% lesser grain yield per spike (averaged across genotypes and in the second years of study), respectively. Likewise, 4- and 8-days heat-stressed plants had 15 and 37% (averaged across genotypes and in the second years of study) lower flag leaf photosynthesis, respectively, compared with control plants. Across the genotypes, 8-days heat caused significantly more grain yield loss in Anaj-17 during the second year than in Ujala-16. Foliar K significantly restored leaf chlorophyll, Pn, Fv/Fm by reducing cellular membrane damage in the heat-stressed plants. This physiological recovery and activation of the plant defensive system by K under high-temperature stress protected the growth and grain development. For example, K'treated plants produced 19% higher 1,000 grain weight in 8 days of heat stress (across genotypes and in the second years of study) compared with water-treated plants under the hot environment of the respective thermal regime. Our study suggests that wheat performance under terminal heat stress can be improved through the exogenous application of K. [ABSTRACT FROM AUTHOR]

High temperature stress at reproductive stages of cotton crop severely affects the yield and quality of cotton crop under changing climatic conditions. To alleviate the adverse effects of high temperature stress on cotton crop, the regulatory effects of potassium (K), zinc (Zn), and boron (B) were assessed by applying different temperature regimes at three reproductive stages of cotton crop under field and glass house conditions. Cotton plants were subjected to low (32/20 °C ± 2), medium (38/24 °C ± 2), and high (45/30 °C ± 2) temperatures under glasshouse, but sown at specific dates in field to provide different temperatures at three reproductive stages. High-temperature stress at squaring, flowering and boll formation stages in both field studies increased relative cell injury (RCI), total soluble proteins (TSP), reactive oxygen species and reduced fiber yield attributes i.e. total number of bolls per plant (TNBPP), number of sympodial branches per plant (NSBPP) and quality traits. For example, RCI, TNBPP and fiber fineness were reduced by 73%, 42% and 29%, respectively under supra thermal regime (SupTR) of glass house study over the optimal thermal regime (OpTR). Foliar application of K and Zn followed by B increased TSP, RWC, TNBPP, NSBPP, fiber fineness, fiber length and fiber strength. Further, foliar spray of K and Zn followed by B also reduced H2 O2 under SupTR and SubTR over the OpTR. The findings of the present study clearly demonstrate that foliar spray of Zn, K and B alleviated adverse effects of high temperature stress at squaring, flowering and boll formation stages and increased seed cotton yield and quality of cotton crop. [ABSTRACT FROM AUTHOR]

An ample quantity of water and sufficient nutrients are required for economical rice production to meet the challenges of ever-increasing food demand. Currently, slow-release nitrogenous fertilizers for efficient inputs utilization and maximum economic yield of field crops are in the limelight for researchers and farmers. In this study, we evaluated the comparative efficacy of conventional urea and coated urea (zinc and neem) on rice grown under aerobic and anaerobic regimes in greenhouse conditions. For the aerobic regime, field capacity was maintained at 80–100% to keep the soil aerated. On the other hand, for the anaerobic regime, pots were covered with a polythene sheet throughout the experimentation to create flooded conditions. All forms of urea, conventional and coated (zinc and neem), improved plant growth, gas exchange, yield, yield contributing parameters, and quality characteristics of rice crop. However, better performance in all attributes was found in the case of zinc-coated urea. Gas exchange attributes (photosynthetic rate, 30%, and stomatal conductance 24%), yield parameters like plant height (29%), tillers per plant (38%), spikelets per spike (31%), grains per panicle (42%), total biomass (53%), and grain yield (45%) were recorded to be maximum in rice plants treated with zinc-coated urea. The highest grain and straw nitrogen contents, grain protein contents, and grain water absorption ratio were also found in plants with zinc-coated urea applications. In irrigation practices, the anaerobic regime was found to be more responsive compared to the aerobic regime regarding rice growth, productivity, and quality traits. Thus, to enhance the productivity and quality of rice grown in anaerobic conditions, zinc-coated urea is best suited as it is more responsive when compared to other forms of urea. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium hirsutum L.) is one of the most important cash crops primarily grown for fiber. It is a perennial crop with indeterminate growth pattern. Nitrogen (N) is extremely important for vegetative growth as balanced N-nutrition improves photosynthesis, resulting in better vegetative growth. Excessive N-supply results in more vegetative growth, which increases the incidence of insect pest and diseases' infestation, pollute surface and ground water, delays maturity and produces low crop yield with poor quality. The use of plant growth regulators (PGRs) is an emerging option to control excessive vegetative growth. The PGRs help in improving plant architecture, boll retention, boll opening, yield and quality by altering growth and physiological processes such as photosynthesis, assimilate partitioning and nutrients dynamic inside the plant body. Mepiquat chloride (1,1-dimethylpiperidinum chloride) is globally used PGR for canopy development and control of excessive vegetative growth in cotton. This study investigated the effect of mepiquat chloride (MC) and N application on yield and yield components of transgenic cotton variety 'BT-FSH-326'. Two N rates (0, 198 kg ha-1) and five MC rates (0, 30,60, 90 and 120 g ha-1) were included in the study. Results revealed that MC and N application improved boll weight, number of bolls per plant, and seed cotton and lint yields. The highest seed cotton and lint yields (3595 kg ha-1 and 1701 kg ha-1, respectively) were observed under foliar application of 198 kg ha-1 N and 120 g ha-1 MC. Fiber length, fiber strength, micronaire and uniformity were significantly improved with foliar application of MC and N. In conclusion, foliar application of MC and N could be helpful in improving yield and fiber quality of cotton. [ABSTRACT FROM AUTHOR]

Drought stress is a major limitation in wheat production around the globe. Organic amendments could be the possible option in semi-arid climatic conditions to mitigate the adverse effects of drought at critical growth stages. Wheat straw biochar (BC0 = Control, BC1 = 3% biochar and BC2 = 5% biochar) was used to alleviate the drought stress at tillering (DTS), flowering (DFS), and grain filling (DGFS) stages. Drought stress significantly reduced the growth and yield of wheat at critical growth stages, with DGFS being the most susceptible stage, resulting in significant yield loss. Biochar application substantially reduced the detrimental effects of drought by improving plant height (15.74%), fertile tiller count (17.14%), spike length (16.61%), grains per spike (13.89%), thousand grain weight (10.4%), and biological yield (13.1%) when compared with the control treatment. Furthermore, physiological parameters such as water use efficiency (38.41%), stomatal conductance (42.76%), chlorophyll a (19.3%), chlorophyll b (22.24%), transpiration rate (39.17%), photosynthetic rate (24.86%), electrolyte leakage (-42.5%) hydrogen peroxide (-18.03%) superoxide dismutase (24.66%), catalase (24.11%) and peroxidase (-13.14%) were also improved by biochar application. The use of principal component analysis linked disparate scales of our findings to explain the changes occurred in wheat growth and yield in response to biochar application under drought circumstances. In essence, using biochar at 5% rate could be a successful strategy to promote wheat grain production by reducing the hazardous impacts of drought stress. [ABSTRACT FROM AUTHOR]

Gradually rising atmospheric temperature is the vital component of the environment, which is anticipated as the riskiest abiotic stress for crop growth. Nanotechnology revolutionizing the agricultural sectors, notably, zinc oxide nanoparticles (nano-ZnO) has captured intensive research interests due to their distinctive properties and numerous applications against abiotic stresses. Mungbean (Vigna radiata L.), being a summer crop, is grown all over the world at an optimum temperature of 28–30°C. A rise in temperature above this range, particularly during the flowering stage, can jeopardize the potential performance of the plant. Hence, an outdoor study was performed to evaluate the effect of multiple suspensions of nano-ZnO (0, 15, 30, 45, and 60 mg l–1) on physicochemical attributes and yield of mungbean crop under heat stress. Heat stress was induced by fine-tuning of sowing time as: S1 is the optimal sowing time having day/night temperatures <40/25°C and S2 and S3 are late sown that were above >40/25°C during the flowering stage. In vitro studies on Zn release from nano-ZnO by inductively coupled plasma mass spectroscopy (ICPMS) disclosed that the Zn release and particles uptake from nano-ZnO were concentration-dependent. Exogenous foliar application of nano-ZnO significantly upstreamed the production of antioxidants and osmolytes to attenuate the shocks of heat stress in S2 and S3. Likewise, nano-ZnO substantially rebated the production of reactive oxygen species in both S2 and S3 that was associated with curtailment in lipid peroxidation. Adding to that, foliar-applied nano-ZnO inflates not only the chlorophyll contents and gas exchange attributes, but also the seeds per pod (SPP) and pods per plant (PPP), which results in the better grain yield under heat stress. Thus, among all the sowing dates, S1 statistically performed better than S2 and S3, although foliar exposure of nano-ZnO boosted up mungbean performance under both the no heat and heat-induced environments. Hence, foliar application of nano-ZnO can be suggested as an efficient way to protect the crop from heat stress-mediated damages with the most negligible chances of nanoparticles delivery to environmental compartments that could be possible in case of soil application. [ABSTRACT FROM AUTHOR]

Among all the abiotic stresses, high temperature stress, especially at flowering, is the major factor causing substantial reduction in cotton yield. To check the effect of foliar applied chitosan (CH), a derivative of chitin, for inducing thermo-tolerance during flowering stage in cotton crop, a field experiment was conducted during 2016 and repeated in 2017. Heat stress was imposed at flowering stage for 4 and 8 days and varied chitosan concentrations (0, 0.2, 0.4, 0.6 and 0.8 g L-1) were applied foliarly after imposing heat stress. Heat was imposed by making the plastic tunnels using perforated transparent polythene sheet. High temperature stress reduced leaf total phenolic contents, total soluble proteins, turgor potential, relative leaf water contents and seed cotton yield. Application of chitosan @ 0.8 g L-1 induced thermo-tolerance by improving all the recorded parameters under high temperature stress while application of chitosan @ 0.6 g L-1 improved the bio-chemical, physiological and yield components under ambient conditions. Conclusively, high temperature stress adversely affected the recorded response while foliar application of high dose of chitosan ameliorated the adverse effects of heat stress at bio-chemical and physiological levels. [ABSTRACT FROM AUTHOR]

Salinity stress is one of the critical factors that limits agricultural productivity particularly in the arid to semi-arid regions worldwide. Elevated concentrations of soluble salts especially NaCl cause osmotic stress, ionic stress and imbalance in the uptake of essential nutrients. Use of salt tolerant rhizobacterial isolates have gained much attention now-a-days on account of their environment friendly nature and effectiveness. Therefore, current study was executed to isolate salt tolerant bacteria from the rhizosphere of maize and check their salt tolerance and plant growth promotion under salinity stress. Selected isolates were further investigated in a growth room trial to compare their efficiency in improving growth and physiology of maize. Salinity stress caused a significant reduction in all the measured traits however, inoculation of rhizobacteria modulated its effects and improved maize growth. Among different strains, SUA-14 caused maximum increment in the shoot length (41%), root length (96%), shoot fresh (1.8 fold) and dry weight (1.3 fold), root fresh (1.76 fold) and dry weight (2 fold), salt tolerance index (1.6 fold), chl 'a' contents (2.6 fold) and chl 'b' contents (2.3 fold) as compared to its respective uninoculated control. Whereas, rhizobacterial strain SHM-5, SHM-13 and SUA-14 showed statistically nonsignificant response in terms of increasing carotenoid contents by 1.8 fold in comparison with their corresponding control. Pearson correlation coefficient showed a strong positive correlation between growth and physiological attributes under salinity stress. On the basis of PCA, SUA-14 found to be the most efficient strain followed by SHM-13. Using 16 S rRNA sequencing, SUA-14 and SHM-13 were identified as Acinetobacter and Bacillus species respectively. [ABSTRACT FROM AUTHOR]

Coincidence of heat stress with reproductive stages of cotton accelerates phenology and deteriorates the quality of cotton fiber. A field study was conducted for 2 years to investigate the beneficial role of foliar selenium (Se) application in alleviating the adverse effects of heat stress on cotton growth, development and yield. The experiment was laid out in a randomized complete block design with split arrangement and replicated thrice. Three levels of heat treatment were assigned in the main plots, that is, H0 = No heat stress; H1 = Heat stress imposed at squaring and H2 = Heat stress imposed at flowering. Four levels of foliar spray of Se at 0, 50, 100 and 150 mg/L were applied in each subplot. A remarkable decrease in phenology, quality attributes and seed cotton yield was observed under 'H1' and 'H2', compared to 'H0'. Similar improvements in phenology were recorded with all three doses of Se application, whereas only the highest Se dose 150 mg/L significantly improved seed cotton yield and fiber quality. Conclusively, heat stress was more detrimental at flowering than at the squaring stage for cotton crop in terms of the examined attributes. Application of Se at 150 mg/L is, therefore, recommended to alleviate heat stress, due to its proven beneficial effect on fiber quality and seed yield. [ABSTRACT FROM AUTHOR]

Weeds produce huge biomass by competing with the main crop for resources has been well established by numerous investigators. The use of weeds, especially aquatic weeds, as an organic source of nutrients such as compost is lacking in the literature. We hypothesized that the use of aquatic weeds i.e. alligator as compost would limit the use of inorganic fertilizers in okra and it would increase the quality of produce. To maximize the effect of inorganic nutrients, it would be easier to use the alligator weed compost as a natural source of nutrients. The crop was sown on 22 July, 2017 and 20 July, 2018 in a randomized complete block design having four replications. The net plot size was 1.8 m x 6 m. The alligator weed compost along with NPK was applied at the time of sowing. Alligator weed compost was applied along with different combinations of NPK i.e. control (recommended dose of NPK 159-114-93 kg ha-1), compost application of 250 kg ha-1, compost application of 500 kg ha-1, compost application of 250 kg ha-1 with 75% recommended NPK, compost application of 250 kg ha-1 with 50% recommended NPK, compost application of 250 kg ha-1 with 25% recommended NPK, compost application of 500 kg ha-1 compost with 75% recommended NPK, compost application of 500 kg ha-1 with 50% recommended NPK and compost application of 500 kg ha-1 with 25% recommended NPK. Compost application of 250 kg ha-1 with 50% recommended NPK significantly reduced the number of days to flowering and increased plant height (cm) at flowering and plant maturity over the alone NPK and other combinations of compost and NPK. Pod yield and yield components were outclassed by the compost application of 250 kg ha-1 with 50% recommended NPK over the other combinations. For example, number of pods per plant and pod yield (t ha-1) were increased by 26%, 20%, respectively averaged across during both years of study over the recommended dose of NPK alone. Similarly, application of compost at 500 kg ha-1 along with NPK 50% of recommended dose enhanced pod potassium and ascorbic acid contents by 76% and 35%, respectively averaged across during both years of study over the control dose of NPK. Conclusively, alligator weed organic source of nutrients could reduce NPK fertilizers as it holds the nutrients applied and also provides the essential nutrients. In future climates, alligator weed compost would be a sustainable and environment friendly approach. [ABSTRACT FROM AUTHOR]

Purpose: To synthesize and characterize some new gabapentin Schiff base derivatives, and to assess their antibacterial, antioxidant and antiepileptic activities. Methods: Four Schiff base derivatives of gabapentin, termed G1, G2, G3 and G4, were synthesized by condensation with benzoin, vanillin, acetophenone, and benzophenone, respectively. Their chemical identities were established by FTIR, 1H NMR and 13C NMR techniques. The new compounds were screened for antibacterial activity using agar well method, antioxidant activity by DPPH assay, and anticonvulsant activity against pentylenetetrazole (PTZ) induced seizures in mice. Results: All the compounds showed antibacterial activity against the test strains to variable degrees, while the parent drug did not exhibit antibacterial activity. The zones of inhibition of compound G2 against Micrococcus luteus (36.2 ± 1.0 mm) and Serratia marcescens (28.2 ± 1.0 mm), and of compound G4 against Stenotrophomonas maltophilia (36.8 ± 1.0 mm) were larger compared to the standard drug, doxycycline, exhibiting zones of inhibition 28.2 ± 1.3, 28.2 ± 0.9 and 20.0 ± 0.9 mm, respectively. In addition, compounds G1 and G2 possessed significantly greater (p < 0.05) radical scavenging activity (82.3 ± 1.8 and 92.3 ± 2.2 %, respectively) than the precursor drug, gabapentin (63.2± 2.6 %). The seizure scores for compounds G1 (0.7 ± 0.06) and G2 (0.9 ± 0.07) were comparable (p > 0.05) with gabapentin (0.8 ± 0.06), while compounds G3 and G4 were less active (p < 0.05) than gabapentin. Conclusion: Compounds G1 and G2 exhibit good antibacterial and antioxidant activities while retaining the anticonvulsant activity of the parent drug, gabapentin, thus making them suitable candidates for further development for the treatment of neurodegenerative pathologies associated with bacterial infections. [ABSTRACT FROM AUTHOR]

Cotton is severely affected by heat stress in most parts of Pakistan which results in poor quality and low cotton yield. Sixty cotton strains were screened against heat stress on the basis of cellular membrane thermostability, chlorophyll contents, canopy temperature, node number of first fruiting branch, boll weight and seed cotton yield to explore the genetics of variation among genotypes for heat tolerance. Five tolerant and five sensitive parents were sorted out and crossed in Line × Tester mating design during 2018.The F1 crosses along with parents were grown in field under normal and heat stress conditions by using two sowing dates to create heat stress in the field. Sowing during 1st week of April was considered as heat stressed because its peak flowering period was supposed to be coincided with the maximum temperature of May-June; while, sowing during 1st week of June was taken as normal because its peak flowering period coincided with normal temperature of August. Data regarding cell membrane themostability (CMT%), chlorophyll contents, canopy temperature, node number to first fruiting branch, bolls/plant, boll weight, ginning out turn and seed cotton yield under normal as well as heat stressed conditions were collected which showed significant differences among genotypes for all the traits under investigation. Most of the traits showed greater mean square for female × male interaction than female and male individual mean squares and higher dominance variance than additive variance. Broad sense heritability for investigated traits was observed in the order of boll weight (94.56), seed cotton yield (94.51), CMT% (91.88), canopy temperature (90.48), node number to first fruiting branch (75.68) and chlorophyll contents (51.93). FH-458 and PB-76 indicated high general combining ability for most of the traits whereas the cross combination FH-458× FH-326 was described as the best cross showing 56.85% better parent heterosis for seed cotton yield under heat stress conditions. The present study was planned to investigate the genetics of some important physiological and agronomic traits of cotton which is a pre-requisite for the development of high yielding cotton varieties under high temperature stress. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium hirsutum L.) is of prime importance because of its quality fiber and edible oil production. Boron (B) is among essential micronutrients for plant growth; it aids in the transfer of sugars and nutrients from leaves to fruit that are involved directly or indirectly in many plant functions. Cotton growth, yield and quality are strongly affected with boron application. A two-year study was conducted to evaluate the impact of foliar applied B (0, 2, 4, 6, 8 and 10 g of B L−1 of water) on the performance of cotton cultivars (FH-113, MNH-786 and CIM-496). The results indicated that growth, yield and quality traits of cotton were significantly influenced by different levels of foliar applied boron as well as cultivars of cotton. Among cotton cultivars, the yield and quality parameters were superior in cultivar "FH-113." Foliar application of boron at 6 g L−1 of water improved leaf area index and leaf area duration and eventually improved the number of bolls per plant, boll retention percentage, average boll weight, lint yield, ginning out turn, fiber length and uniformity ratio of cotton. Foliar application of B at 6 g per liter of water, showed promising results by improving growth and quality parameters and is recommend to enhance the economical yield production of cotton cultivar "FH-113" with improved quality. [ABSTRACT FROM AUTHOR]

Water deficit reduces crop productivity. Cytokinin (CK) is a growth regulator which is a potent coordinator between physiological traits and senescence. A study was carried out to investigate the drought ameliorating effects of exogenous applied cytokinin in wheat. Experiment was comprised of seven treatments(C= Control, DT= Drought at tillering, DT+CK= Drought at tillering + CK, DA= Drought at anthesis, DA+CK= Drought at anthesis + CK, DG= Drought at grain filling, DG+CK= Drought at grain filling + CK).Cytokinin was applied foliarly@ 25 mg L-1 solution of cytokinins. CK application under drought stress significantly increased growth and yield characteristics (P< 0.05). An increase of 4.36%, 7.21% and 5.55% in grain yield was recorded with CK application when drought was applied at tillering, anthesis and grain filling stage, respectively. Other physiological parameters increased by CK included photosynthesis rate, leaf area index, chlorophyll content, activities of ascorbate peroxidase, catalase, peroxidase, superoxide dismutase and endogenous hormonal level of kernels. It was concluded that CK improved plant growth, minimized ill impacts of reactive oxygen species and increase transfer of assimilates to grains under drought. [ABSTRACT FROM AUTHOR]

Climate change is imposing high temperature resulting in prolonged drought episodes and shrinking of fresh water resources across the globe. In this scenario, even drought tolerant crops like quinoa are also losing significant yield. However, this study was planned to investigate the impact of drought on quinoa at critical growth stages and bacterial inoculation to improve drought tolerance. Drought was imposed by maintaining 25% pot water holding capacity (PWC) at multiple leaf, flowering, and seed filling stage (DSFS), while 80% PWC was considered as control. Three strains of plant growth promoting rhizobacteria (PGPR) named as: Bacillus licheniformis, Pseudomonas fluorescens, and Azospirillum brasilense were inoculated with quinoa seeds before sowing with respect to drought treatments. PGPR inoculation mitigated the drastic effects of drought by improving crop growth, net assimilation rate, water use efficiency, leaf chlorophyll, and phenolic contents, all of these ultimately contributed to improvement in grain yield and its contributing attributes. Moreover, PGPR markedly improves the grain quality attributes including protein, phosphorus, and potassium contents. Principal component analysis linked the different scales of study and demonstrated the potential of physio-biochemical traits to explain the quinoa yield variations under drought condition with response to PGPR inoculation. Among different PGPR, A. brasilense was found most effective both under normal and drought conditions. Overall, DSFS has more detrimental effects among critical growth stages of quinoa and A. brasilense can be used as a shotgun tactic to ameliorate drought stress in quinoa. [ABSTRACT FROM AUTHOR]

Drought is a major constraint for agricultural productivity worldwide, and it is likely to further increase. Different strategies are required to mitigate drought stress in plants. In a two-year study that conducted at agronomic research area of the Islamia University of Bahawalpur, we investigated the role of rhizobacteria (RB) and cytokinins (Ck) on drought tolerance, nutrient uptake, yield, and physiological parameters in wheat under drought stress at different developmental stages (tillering, anthesis, and grain filling). Thirteen treatments used were well-watered control plants without RB or Ck, drought at tillering, anthesis, or grain filling without or with RB alone, Ck alone, or combination of both (RB+Ck). In both years, and at the different stages, measured parameters were highest in the well-watered plants but lowest in drought-stressed plants. Application of RB and Ck to drought-stressed plants increased these parameters in the order RB+Ck > RB > Ck. In some cases, under drought stress, there was no difference between inoculation with RB and application of Ck. It was concluded that the combined application of RB and Ck could play a significant role in improving wheat yield and also alleviation of stress under drought condition. [ABSTRACT FROM AUTHOR]

Plant growth-promoting rhizobacteria (PGPR) play an important role in improving crop growth but have not been studied sufficiently. A wire house experiment was conducted in Pakistan to determine the combined effect of inoculating wheat seeds with PGPR on the subsequent growth and yield of the wheat. The experiment included four treatments: T0 – no-inoculation (control), T1 – Azospirillum brasilense inoculation, T2 – Rhizobium pisi inoculation and T3 – co-inoculation with A. brasilense and R. pisi. Development and growth attributes, as well as final yield of wheat, were studied. Co-inoculation of seeds with both strains increased significantly wheat grain yield, the number of grains per plant and 1000-grain weight by 36%, 11% and 17%, respectively, compared to non-inoculated control. While crop growth rate increased for, respectively, 5.5% and 33% at tillering and flag leaf stages, corresponding values for T3 were about 9% and 14% higher than values for sole inoculations in T1 and T2. Co-inoculation also significantly increased leaf epicuticular wax and relative water content as compared to the control treatment. Thus, inoculation of wheat seeds with A. brasilense and R. pisi and their combination is a promising method to improve growth, yield and quality of wheat. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the general combining ability effects of parents and specific combining ability effects of crosses under normal and water deficit condition for various traits related to fibre quality. For this purpose, 50 F1 crosses and their 15 parents was field planted under two different moisture regimes i.e. normal and water deficit condition in the experimental area of Department of Plant Breeding and Genetics, UAF. Analysis of variance under normal and drought condition revealed that genotypes showed highly significant differences for all the traits under both conditions. For most of fibre quality traits, under normal condition, among the lines, the good general combiners were IUB-212 and FH-113 and poor general combiners were VH-295 and NS-121. Among the testers, the good general combiners were IR-3, CIM-443 and S-12 and poor general combiners were MNH-147 and FH-1000. Under the drought condition, among the lines, the good general combiner was IUB-212 and poor general combiners were VH-295 and FH-142. Among the testers, the good general combiner was S-12 and poor general combiners were MNH-147 and IR-3. For most of fibre quality traits the best specific combiner were VH-144 × CIM-443 and AA-802 × S-12 under normal condition while under drought condition the best specific combiner were VH-144 × CIM-443, VH-295 × IR-3, VH-144 × FH-1000 and VH-295 × CIM-443. The variance due to specific combining ability was greater as compared to the general combining ability variance for all the traits indicating the dominant role of non-additive genes under normal and drought condition. The crosses VH-144 × CIM-443 and VH-295 × IR-3 can be used in variety development program for drought prone areas of Pakistan with high specific combining ability for fibre quality traits under drought condition. All fibre quality traits having non-additive gene action suggested usage of this material in the hybrid development programme in cotton. [ABSTRACT FROM AUTHOR]

The ability to identify the vulnerable regions within the crop fields assist the farmers in executing the counter plans precisely. In this regard, the unmanned aerial vehicles (UAVs) equipped with red-green-blue and multispectral sensors have added a new dimension in precision agriculture for a broad range of applications. In this study, we present the transformation of an off-the-shelf quadrotor platform into an aerial-crop-observer by adding customized payload capable of delivering high-resolution multispectral imagery. The main objective of the study was to aerially quantify the response of wheat crop under the influence of different elements critical to crop health, i.e. nitrogen (N), phosphorus, zinc, irrigation levels (I), and agro-climatological conditions. Two different experimental plots with different varieties of wheat crop were selected for the study. The vegetation indices were derived after all the necessary radiometric and geometrical corrections. The linear estimation models were developed to assess the grain yield, aboveground biomass, and leaf area index. Our results indicate that high-resolution multispectral imagery acquired through lightweight UAVs offers a standing potential for quantifying aerial observations of wheat crop under a variety of field-inputs. The study is characterized through respective soil analysis, applied field inputs, calibration of aerial image sensors, the agro-climatological observations, and derivations of vegetation indices. [ABSTRACT FROM AUTHOR]