Search

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]

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]

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]

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]

Wheat is an important staple crop not only in Pakistan but all over the globe. Although the area dedicated to wheat cultivation expands annually, the quantity of wheat harvested is declining due to various biotic and abiotic factors. Global wheat production and output have suffered as a result of the drought, which is largely driven by a lack of water and environmental factors. Organic fertilizers have been shown to reduce the severity of drought. The current research was conducted in semi-arid climates to mitigate the negative effects of drought on wheat during its critical tillering (DTS), flowering (DFS), and grain filling (DGFS) stages through the application of three different abscisic acid treatments: ABA0 (0 mgL−1) control, ABA1 (100 mgL−1) and ABA2 (200 mgL−1). Wheat growth and yield characteristics were severely harmed by drought stress across all critical development stages, with the DGFS stage being particularly vulnerable and leading to a considerable loss in yield. Plant height was increased by 24.25%, the number of fertile tillers by 25.66%, spike length by 17.24%, the number of spikelets per spike by 16.68%, grain count per spike by 11.98%, thousand-grain weight by 14.34%, grain yield by 26.93% and biological yield by 14.55% when abscisic acid (ABA) was applied instead of the control treatment. Moreover, ABA2 increased the more physiological indices (water use efficiency (36.12%), stomatal conductance (44.23%), chlorophyll a (24.5%), chlorophyll b (29.8%), transpiration rate (23.03%), photosynthetic rate (24.84%), electrolyte leakage (− 38.76%) hydrogen peroxide (− 18.09%) superoxide dismutase (15.3%), catalase (20.8%), peroxidase (− 18.09%), and malondialdehyde (− 13.7%)) of drought-stressed wheat as compared to other treatments. In the case of N, P, and K contents in grain were maximally improved with the application of ABA2. Through the use of principal component analysis, we were able to correlate our results across scales and provide an explanation for the observed effects of ABA on wheat growth and production under arid conditions. Overall, ABA application at a rate of 200 mgL−1 is an effective technique to boost wheat grain output by mitigating the negative effects of drought stress. [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]

Highlights • Removal of early fruiting branches (REFB) enhanced Cry1Ac , chlorophyll in Bt cotton. • Nitrogen and seed cotton yield were improved under REFB compared to "no REFB". • Insect damaged bolls and senescence were decreased under REFB compared to "no REFB". • Correlation of biochemical transformations with morphological attributes was recorded. • REFB proved a potent tool to regulate Cry1AC , growth and yield in cotton. Abstract Excessive use of insecticides, degradation of Cry1Ac protein, insect resistance and premature senescence in cotton are serious threats to the sustainable cotton production. An experiment was conducted to manage these adversities and to determine dependence of morphological attribute on physiochemical responses. Experiments were conducted at University of Agriculture Faisalabad, Pakistan over two years (2015, 2016) and two locations. The experiment was laid out in randomized complete block design under factorial arrangement. Treatments were comprised of branch removal viz. R 0 = No removal of early fruit branches; R 1 = Removal of two early fruit branches (REFB) and genotypes V 1 = MNH-886 and V 2 = FH-142. Results revealed that Cry1Ac (33%) and nitrogen concentration (16%) were increased under REFB compared to no REFB over years and locations. Chlorophyll a and b contents were improved by 11 and 6% under REFB compared to no REFB over two localities and years. While, SOD, POD and CAT activities were increased by 13, 13 and 10%, respectively under REFB compared to no REFB. Nodes above white flower (5 days), nodes for first fruiting branch and seed cotton yield were enhanced by 14, 15 and 17%, respectively under REFB compared to no REFB over years and locations. Number of insect damaged bolls were decreased by 28% under REFB compared to control over years and locations. More promising responses were recorded for MNH-886 compared to FH-142 over REFB, years and locations. Conclusively, all physiochemical and agronomic attributes were improved, and senescence and insect attack were decreased in both genotypes over the spatial and temporal variations. Significant and strong correlation of physiochemical attributes with morphological attributes were recorded over years and locations. [ABSTRACT FROM AUTHOR]

The present study investigated the induced drought tolerance in sunflower through foliar application of potassium (K) at critical growth stages (head formation or achene filling). Five genotypes of sunflower (G-101, SF-187, Hysun-33, Hysun-38, and 64-A-93) were tested for drought tolerance at −0.55, −1.36, and −1.60 MPa osmotic potential using polyethylene glycol 6000. Hysun-33 showed the highest stress tolerance index as calculated from germination percentage, seedling height, root length, and dry matter. This genotype was further evaluated in the field under drought at head formation or achene filling stages, with or without 1% K foliar application. Treatments were arranged in a randomized complete block design with three replicates. Drought at head formation or achene filling stage significantly decreased biological yield, head diameter, plant height, 1000 achene weight, and achene yield as compared to unstressed control. Potassium application significantly improved all the aforementioned parameters and therefore could be a better strategy for ameliorating drought stress in sunflower. [ABSTRACT FROM AUTHOR]

Heat stress at reproductive stages of cotton is a leading encumbrance to accomplish yield potential. An experiment was conducted to alleviate adversities of terminal heat stress on cotton. Experiment was conducted at University of Agriculture Faisalabad, Pakistan during 2013 and repeated in 2014 using Randomized Complete Block Design (RCBD) with split arrangement. Treatments were comprised of heat stress in main plots, viz., H0 = no heat imposition, H1 = heat imposition at squaring, and H2 = heat imposition at flowering. Selenium was foliar applied in split plot, viz., Se0 = 0, Se50 = 50, Se100 = 100, and Se150 = 150 mg L−1. Cell membrane thermostability, soluble proteins, and total phenolics were reduced significantly under heat stress leading to reduced cotton yield and related components. Maximum membrane thermostability, total phenolics, soluble proteins, opened bolls, boll weight, sympodial branches, and seed cotton yield were recorded with the application 150 mg Se L−1. [ABSTRACT FROM AUTHOR]

Imbalance use of nutrients is one of the main reasons of low yield of the sunflower. The use of essential macro and micronutrients in the right proportion and optimum quantity is the key factor to boost and sustain the crop productivity. Among plant nutrient deficiencies, nitrogen and boron limitation is the most prevailing problem in the world, which is involved in the decline of sunflower production. Therefore, a field experiment was conducted to examine the combined effect of nitrogen and boron on growth, yield and oil quality of sunflower hybrids during 2009. Two nitrogen levels (0 and 150 kg ha-1) and three boron levels (0, 2 and 3 kg ha-1) were tested against two sunflower hybrids (Hysun-33 and DK-4040). All the growth and yield components like plant height, stem diameter, head diameter, achene and biological yield were significantly affected by varying levels of nitrogen and boron fertilizers. Results revealed that boron/nitrogen synergetic effect additively increased yield and yield components in sunflower plant. The oil and protein contents of sunflower were significantly affected by varying levels of both nitrogen and boron and maximum oil contents were observed when boron was applied @ 2 kg ha-1 with 0 kg ha-1 of nitrogen whereas maximum protein contents were recorded when 2 kg ha-1 boron was applied in combination with 150 kg ha-1 of nitrogen of both hybrids (H1=Hysun-33 and H2=DK-4040). The combined application of nitrogen (N1) (150 kg ha-1) and boronB1 (2 kg ha-1) also resulted in maximum net income (88518 Rs.) and benefit cost ratio (1.25) for Hysun-33. [ABSTRACT FROM AUTHOR]

Commercial cultivation of Bt cotton produced higher boll load which led to stiff inter-original competition for photosynthates, resulting in early cessation of growth (premature senescence) due to more availability of sink and less sources. To overcome this problem, field experiment was conducted during 2011 and 2012 using five treatments of plant growth manipulation viz. no fruiting branch removal (F1), removal of first fruiting branch (F2), removal of first and second fruiting branch (F3), removal of all squares from first fruiting branch (F4), removal of all squares from first and second fruiting branches (F5), and three potassium (K) application rates viz. 50 kg ha−1(K1), 100 kg ha−1(K2), and 150 kg ha−1(K3). More nodes above white flower were recorded in F5, followed by F3, while minimum were recorded in F1. Among potassium levels, maximum nodes above white flower were recorded in K3followed by K2and K1during both years of study. Plant height recorded at physiological cutout stage or at maturity stage showed that plants gained more height with removal of all squares from first tosecond fruiting branches with higher potassium dose. Leaf K increased with increasing applied potassium and also with square/branch removal. So early removal of squares/fruiting branches along with higher potassium dose helped in delaying canopy senescence in Bt cotton. [ABSTRACT FROM PUBLISHER]

Zinc and Boron dearth is an imperative soil constraint in Pakistan. Zinc (Zn) and boron (B) deficiency in soil is primary hindrance to achieve yield potential of maize. An experiment was conducted with the objectives to optimize methods of B and Zn application in maize and ultimately enhance profitability. The experiment was laid out in randomized complete block design with factorial arrangement during autumn 2015. Treatments were replicated three times. The treatments were comprised of C = no Zn and B (Control); Zn (S) = soil application of Zn @ of 12 kg ha-1; B (S): soil application of B @ 3 kg ha-1; Zn (F) = foliar application of 1% Zn at 9th leaf stage; B (F) = foliar application of 0.5% B at 9th leaf stage; Zn (S) + B (S) = soil application of Zn @ 12 kg ha-1 + B @ of 3 kg ha-1 and Zn (F) + B (F) = foliar application of 1% Zn + 0.5% B at 9 leaf stage. Foliar application of Zn and B produced more plant height, cob length, girth, stem girth, shelling percentage, number of grains per cob, 1000-grain weight, harvest index, grain and biological yield. Maximum marginal rate of return was obtained with foliar application of both Zn and B and using foliar Zn alone. Integrated B and Zn application produced more marginal rate of returns both in soil and foliar applications. Use of foliar Zn application also depicted promising results while foliar or soil B application without using Zn enhanced cost of production. [ABSTRACT FROM AUTHOR]

Effect of foliar applied benzoic acid on growth, earliness and nutrients' uptake in heat stressed cotton (Gossypium hirsutum L.) was studied at Department of Agronomy, University of Agriculture, Faisalabad, Pakistan during Kharif 2014. Experiment was laid out in RCBD with split plot arrangement in three replications with net plot size of 3 m × 4.5 m. Treatments included: (a) two levels of heat stress; plots without polythene sheet (control) and plots covered with polythene sheet at square initiation for one week; (b) six benzoic acid levels; viz. control (no spray), control (water spray), benzoic acid spray at 0.25, 0.50, 0.75 and 1.00 mM. The crop was sown on 75 cm apart ridges and plant to plant distance was maintained at 30 cm. All other agronomic practices were kept normal and uniform. The standard procedures were adopted for recording the data on various cotton parameters. The results showed that imposition of heat stress affected cotton phenology and caused all earliness related parameters to occur earlier than control. Heat stress also reduced cotton plants' ability to uptake nutrients (N,P,K Zn and B). However, when crop was applied with benzoic acid, it ameliorated the negative impact of heat stress. Increase in benzoic acid spray concentration increased all above mentioned parameters but upto some extent and then started to decrease. It was concluded that application of 0.75 mM benzoic acid spray improved cotton performance (growth and nutrients' uptake) under both, natural and heat induced environments. Economic analysis also showed that application of 0.75 mM benzoic acid on cotton crop gave maximum net income and benefit cost ratio. [ABSTRACT FROM AUTHOR]

Water scarcity is the most serious abiotic stress restricting plant productivity throughout the world. Losses in crop yield due to drought exceed from losses caused by other environmental factors. In this review article different morphological, physiological and yield attributes of cotton under drought stress, mechanism of drought induced losses and various management strategies to mitigate drought stress have been discussed. Drought stress reduces growth of leaf, stem and root, interferes with leaf water relations, photosynthesis, respiration, reduces water-use efficiency and ultimately yield of cotton. Under water deficit conditions cotton shows various responses to cope with drought stress. The major mechanisms include accumulation of osmoregulators, plant growth regulators and production of heat shock proteins. Different management strategies to alleviate water deficit stress like foliar application of osmolytes, potassium and growth regulators (hormones), various drought responsive genes, proteins at molecular level, screening and breeding programs against drought tolerance and mulching are also discussed in this paper. [ABSTRACT FROM AUTHOR]

Cotton is perennial plant with indeterminate growth habit. However it has been adopted as annual, so efforts like topping and optimum nitrogen levels to modify its architecture can play a role in improving its success as annual. A field experiment to study the effect of topping under different nitrogen levels on earliness and yield of cotton (Gossypium hirsutum L.) was conducted at Agronomic Research Area, University of Agriculture, Faisalabad, during kharif 2013. The crop was sown on ridges on May 24, 2013 using seed rate of 20 kg ha-1. The experiment was laid out in Randomized Complete Block Design (RCBD) with factorial arrangement having three replications. Treatments included four topping levels: control (no topping), topping at 90 cm, 120 cm and 150 cm height; three nitrogen levels: 150, 200 and 250 kg ha-1. Net plot size was 6 m x 3 m. Maximum days to first floral bud initiation (44.68), appearance of first flower (65.64), first boll splition (105.47) and monopodial branches per plant (0.81) were recorded at 250 kg N ha-1. Minimum days for first floral bud initiation (36.66), appearance of first flower (55.97), first boll splition (86.31) and monopodial branches per plant (0.33) were recorded with application of 150 kg N ha-1. While topping did show non-significant effect on these earliness related parameters. Number of sympodial branches was significantly affected by topping only; with maximum values recorded in no topping closely followed by topping at 150 cm height. Values showed that 90 cm tall plants produced maximum seed cotton yield when supplied with 150 kg N ha-1; 120 cm tall plants gave maximum seed cotton with 200 kg N ha-1 while 150 cm tall cotton plants needed 250 kg N ha-1 for highest seed cotton production. In conclusion, cotton growth can be manipulated successfully for better performance by topping provided N dose is monitored. [ABSTRACT FROM AUTHOR]

Removal of early fruiting branches with greater potassium doses caused more source and no sink at early stages of growth, leading to improved yield, yield components, and fiber quality traits in Bt cotton. The study used manual alteration of plant architecture (F1, no branch removal; F2, removal of first fruiting branch; F3, removal of first and second fruiting branches; F4, removal of all squares from first fruiting branch; F5, removal of all squares from first and second fruiting branches) and potassium rates (50, 100, and 150 kg ha−1) in a randomized complete block design and was repeated for 2 years (2011 and 2012). Increasing potassium application increased total bolls per plant and cotton yield to the greatest levels in F3and F5, against lowest level in the control. Ginning out turn, fiber length, seed oil, and seed protein content were influenced by fruiting branch or square removal but the difference was less. Increasing potassium improved seed and fiber quality. [ABSTRACT FROM AUTHOR]

Global warming is posing threat to agriculture through increasing incidence of abiotic stresses particularly drought stress. Water stress at grain filling stage of wheat crop is detrimental to crop mineral nutrition because it reduces soil moisture and inhibits the optimal crop growth and development by decreasing the availability of nutrients uptake. Glycine betaine and potassium production is accelerated in plants particularly under drought stress conditions for regulation of cell homeostasis (protective mechanism). For the reason, a pot and two field trials were conducted to evaluate the impact of foliar application of glycine betaine and potassium alone and in combination, when water was withheld at grain filling stage. Different doses of glycine betaine (0, 50, 100 and 150 mM) and potassium (0, 0.5, 1.0 and 1.5%) and all possible combinations were used. After harvesting, plant mineral content (N, P, K, Na, and Ca) was assessed. The results indicated that the application of K at 1.5% in combination with glycine betaine at 100 mM was most beneficial in diluting the impact of water stress at grain filling stage. Further it was suggested that the responses of wheat crop to these osmolytes should be studies at molecular level under drought to identify the mechanisms which are tangled for variable plant responses. [ABSTRACT FROM AUTHOR]

Removal of early fruiting branches with optimum nitrogen dose caused more source and no sink at early growth stages leading to delay in onset and progression of senescence in Bt cotton (Gossypium hirsutum L.). Field trials were conducted at Students' Farm, University of Agriculture, Faisalabad, during 2011 and 2012. Experiments were laid out in a randomized complete block design (RCBD) with factorial arrangement using three replications. Study comprised of manual alteration of plant architecture i.e. F1: no fruiting branch removal, F2: removal of first fruiting branch, F3: removal of first and second fruiting branch, F4: removal of all squares (floral bud) from first fruiting branch, F5: removal of all squares from first and second fruiting branch; and nitrogen rates i.e. N1: 175, N2: 225 and N3: 275 kg ha-1. More monopodial and sympodial branches per plant were recorded in F5 and F3 with higher and medium level of nitrogen application while minimum was recorded in F1 at all levels of nitrogen. Increasing nitrogen application increased total bolls per plant and cotton yield to highest level in F3 and F5 against lowest in control at all levels of nitrogen. Potassium concentration in leaf increased with increasing nitrogen application in F3 and F5 treatment while in F1, F2 and F3 medium and higher nitrogen application was at par with each other. Ginning out turn, fiber length, seed oil and seed protein content were influenced by fruiting branch or square removal but difference was less. Increasing nitrogen improved seed oil and protein content and fiber quality (length, strength, fineness, elongation etc.) [ABSTRACT FROM AUTHOR]

Drought is the major abiotic limiting factor for healthy crop growth. Glycinebetaine applied under drought mitigates the adverse effect of drought and improved the plant's tolerance. The present investigation was conducted to find out the response of wheat (Triticum aestivum L.) cultivars (Lasani-2008, Auqab-2000) under water deficit conditions to exogenous application of 100 mM glycinebetaine at different growth stages, Zadoks GS 22, GS 60 and GS 73, representing tillering, flower initiation and grain filling stages, respectively. The objective was to find out the best glycinebetaine (GB) application stage for mitigating the negative effect of drought stress on wheat plants. During investigation various growth traits (plant height, spike length, number of spikelets per spike, number of grains per spike, 1000-grain weight and grain yield per plant) and physiological parameters (water potential, osmotic potential and turgor potential) of crop were recorded using standard procedures. Drought stress at all three critical growth stages adversely affected (P<0.05) all the growth, yield and physiological components of wheat plant. The exogenous application of GB at all three critical growth stages improved the drought tolerance of plants and improved the growth, yield and physiological performance of wheat, however, grain filling stage was found more responsive. [ABSTRACT FROM AUTHOR]

Sunflower genotypes perform differently under different water regimes. Drought stress at various growth stages drastically reduces the growth, development and yield of sunflower hybrids. However, exogenous application of abscisic acid helps in mitigating drought stress by improving growth, development and yield of sunflower. In the present study, three sunflower hybrids viz. DK-4040 (large stature), S-278 (medium stature) and SF-187 (short stature) were exposed to varied irrigation regimes and abscisic acid application schedule i.e. T1: four irrigations with schedule (25DAS, at bud, flower initiation and at achene formation) and with no ABA spray,T2: three irrigations with schedule (25DAS, at flower initiation and at achene formation) and with no ABA spray, T3: three irrigations with schedule (25DAS, at flower initiation and at achene formation) and with 8µMABA spray at bud initiation, T4: three irrigations with schedule (25DAS, at bud initiation and at achene formation) and with no ABA spray, T5: three irrigations with schedule (25DAS, at bud initiation and at achene formation) and with 8µM ABA spray at flower initiation. Experiment was laid out in Randomized Complete Design with factorial arrangement having three replications. ABA application at bud or at flower initiation under drought stress helped in mitigating the detrimental effects by improving growth and yield of sunflower hybrids. Enhancement in drought tolerance of sunflower genotypes was better when ABA was applied at bud initiation stage than that of at flower initiation stage under drought. Improvements in head diameter, achenes per head, 1000-achene weight, achene yield, oil yield, biological yield, harvest index, leaf area index and crop growth rate was recorded. Sunflower hybrid DK-4040 showed more improvement in drought tolerance byfoliar application of ABA under water deficit stress than that of the SF-187 and S-278. It is suggested that sunflower hybrid DK 4040 should be grown under drought stress by foliar application of ABA at bud initiation stage. [ABSTRACT FROM AUTHOR]

Adopting new technology always involves advantages and risks; Bt cotton (Gossypium hirsutum L.) is a new technology well known in developed countries for its many advantages, such as reduced pesticide application, better insect pest control, and higher lint yield. However, its success in developing countries is still a question mark. Global adoption of Bt cotton has risen dramatically from 0.76 million ha when introduced in 1996 to 7.85 million ha in the 2005 cotton-growing season where 54% of the cotton crops in the USA, 76% in China, and 80% in Australia were grown with single or multiple Bt genes. Bollworms are serious cotton pests causing 30-40% yield reduction in Pakistan and 20-66% potential crop losses in India. The major advances shown in this review include: (1) Evolution of Bt cotton may prove to be a green revolution to enhance cotton yield; (2) adoption of Bt cotton by farmers is increasing due to its beneficial environmental effects by reducing pesticide application: however, a high seed price has compelled farmers to use illegal non-approved Bt causing huge damage to crops because of low tolerance to insect pests; and (3) some factors responsible for changes in the efficiency of the Bt gene and Bt cotton yield include internal phenology (genetics), atmospheric changes (CO2 concentration), nutrition, insect pests, boll distribution pattern, disease and nematodes, removal of fruiting branch and/or floral bud, introduction of Bt gene, and terpenoids and tannin production in the plant body. [ABSTRACT FROM AUTHOR]

• Heat stress effects on plant water relation and gas exchange components. • High temperature increased the contents of TSP, GR and DPPH. • H 2 O 2 outclassed all others signaling molecules followed by ASA and MLE. • H 2 O 2 enhanced GS, seed index and ginning out turn. • H 2 O 2 improved fiber quality under temperature regimes. The climate change and global warming driven rise in temperature and unpredictable occurrence of heat waves impede cotton plants growth and development. Therefore, environmental friendly thermotolerance strategies are required to sustain optimum crop yield under stressful conditions. Reports on heat stress impacts on plant water relations, gas exchange attributes and physiological parameters, at different reproductive stages of cotton, under controlled and natural conditions are lacking. To investigate the impact of temperature and exogenous application of elicitors, a medium heat tolerant cotton genotype was exposed to control/optimal (30/20 °C), medium (38/24 °C) and high (45/30 °C) temperature stress at squaring, flowering and boll formation stages. Plants were staggered to April (early), May (normal) and June (late) sowing dates under field conditions. Growth regulators, salicylic acid (SA-50 ppm), bio-stimulant moringa leaf extract (MLE-30 times diluted) and signaling molecules, i.e. hydrogen peroxide (H 2 O 2 -30 ppm) and ascorbic acid (ASA-70 ppm), were applied foliarly one day prior to temperature stress treatments. Several physio-biochemical parameters, such as leaf non-enzymatic antioxidant, gas exchange attributes and water relations were measured seven-days after exposure to medium and high temperature regimes. Elevated temperature (45/30 °C) increased the content of total soluble proteins (TSP), activity of glutathione reductase (GR), radical scavenging capacity (DPPH%) and H 2 O 2 generation by 64 %, 26 %, 39 % and 57 %, respectively, compared with optimal temperature plants (control). Similarly, the stomatal conductance (GS), seed index and ginning out turn (GOT%) were reduced by 49 %, 47 % and 44 %, respectively under the high temperature regime compared with control temperature regime. Gas exchange components, water relations, seed index and GOT were also reduced under medium and high temperature regimes. Among the exogenous applications, H 2 O 2 showed profound alleviation of temperature stress, followed by ASA and MLE. Foliar application of H 2 O 2 increased TSP, GR and DPPH% by 1.16 folds, 70 % and 82 % (averaged across during three reproductive stages); while, GS, seed index and GOT were increased by 45 %, 20 %, 22 % under high temperature stress over the control plants of the same thermal regime. In conclusion, oxidative burst and antioxidant activities were increased, whereas stomatal conductance, seed index and GOT were reduced with increasing temperature from 30/20 °C to 38/24 °C and from 38/24 °C to 45/30 °C. On the other hand, H 2 O 2 improved thermotolerance of cotton plants via maintaining cellular redox balance, gas exchange attributes, and further enhanced seed weight and ginning out turn under medium and high temperature regimes. [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]

Coincidence of high temperature with terminal reproductive pheno-stages of cotton is chief constraint to achieve yield potential. This high temperature interfere plant defensive system, physiological process, water relations and lint yield production. In this study, we modulated the detrimental outcomes of heat stress on cotton through the foliar spray of nutrients. Cotton crop was exposed to sub-optimal and supra-optimal thermal regimes for a period of one week at squaring, flowering and boll formation stages under glass house and field conditions. Foliar spray of potassium (K-1.5%), zinc (Zn-0.2%) and boron (B-0.1%) were applied at three reproductive stages one day prior to expose high temperature regimes. High temperature increased lipid membrane damage through increased malondialdehyde (MDA) contents in cotton leaves. High temperature stress also reduced leaf chlorophyll contents, net photosynthetic rate, stomatal conductance, water potential, averaged boll weight (g) and seed cotton yield per plant. Various nutrients variably influenced growth and physiology of heat-stressed cotton plants. Zinc outclassed all other nutrients in increasing leaf SOD, CAT, POX, AsA, TPC activity, chlorophyll contents, net photosynthetic rate, stomatal conductance, water potential, boll weight and seed cotton yield per plant. For example, zinc improved seed cotton yield under supra-optimal thermal regime by 17% and under sub-optimal thermal regime by 12% of glasshouse study while 19% under high temperature sowing dates of field study than the water treated plants under the same temperatures. Conclusively, increasing intensities of temperature adversely affected the recorded responses of cotton and exogenous application of Zn efficaciously alleviated heat induced perturbations. Moreover, exogenous nutrients mediated upregulations in physiochemical attributes induced heat tolerance at morphological level. [ABSTRACT FROM AUTHOR]

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper. [ABSTRACT FROM AUTHOR]

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]

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 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]

Soybean is one of the most important legumes rich in high quality protein and oil. Its cultivation in Pakistan is restricted to few areas due to poor germination and low seed viability. The optimum yield and quality of this oil seed crop is noticeably affected by its lower germination rate. To address the problem of poor germination and low seed viability, a field study was conducted at Agronomic Research Area, University of Agriculture Faisalabad, during spring 2011. The experiment was composed of two soybean varieties (Faisal Soybean and 95-1) and five priming techniques (control, on-farm priming, hydro priming, hydration inoculation and osmo priming with 0.5% urea solution. Results revealed that hydro priming, on-farm priming and hydration inoculation significantly reduced the time to 50% emergence (E50), mean emergence time (MET) and emergence index (EI) of both soybean varieties. Moreover, osmo priming had no significant effect on E50, MET and EI that was at par with control. On an average, days to maturity (96.42), plant height (25.84 cm), plant population at harvest (25.22), 1000-seed weight (94.97 g), seed yield (1.71 t ha-1) and biological yield (4.37 t ha-1) of both soybean varieties was significantly improved by hydration inoculation and hydro priming techniques. It was concluded that hydration inoculation and hydro priming were best techniques for better stand establishment of soybean and may be recommended for farmers having the problem of less germination and poor stand establishment. [ABSTRACT FROM AUTHOR]

Wheat is one of the major staple food of the world, which is badly affected by water deficit stress. To fulfill the dietary needs of increasing population with depleting water resources there is need to adopt technologies which result in sufficient crop yield with less water consumption. One of them is partial root zone drying (PRD). Keeping in view these conditions, a wire house experiment was conducted at University College of Agriculture and Environmental Sciences, The Islamia University Bahawalpur during 2015, to screen out the different wheat genotypes for PRD. Five approved local wheat cultivars (V 1 = Galaxy-2013, V 2 = Punjab-2011, V 3 = Faisalabad-2008, V 4 = Lasani-2008 and V 5 = V.8200) and two irrigation levels (I 1 = control irrigation and I 2 = PRD irrigation) with completely randomized design having four replications were used in the experiment. Among the varieties Galaxy-2013 performed the best and attained maximum plant height, leaf area, stomatal conductance, photosynthesis, total sugars, proline contents and antioxidant enzymes activities and minimum values of all growth and physiological parameters were recorded in variety V.8200. For irrigation levels, higher values of growth, physiological and water related parameters were recorded in control treatment (I 1 ) except leaf water potential, osmotic potential, total sugars and proline contents. However enzymes activities were higher under PRD treatment for all varieties. It was concluded that Galaxy-2013 was the most compatible and V.8200 was the most susceptible variety under PRD condition, respectively and more quality traits and enzymatic activities were recorded under PRD condition as compared to control treatment. [ABSTRACT FROM AUTHOR]

Oilseed rape (Brassica napus L.) is an important oilseed crop worldwide. Drought is the most detrimental environmental factor affecting the crop plants from germination up to maturity. A complete perspective of the effect of drought is crucial in understanding the influence of climate variability on rape cultivation. Water deficit stress affects morphology, physiology and development of rape crop. The aim of this article is to present an outline of the effects of drought stress on the growth, physiological processes, yield and quality parameters of rape crop. When drought stress occurs at critical stages, both short and long term, it can adversely affect important growth and physiological processes like leaf area, root growth, shoot growth, excised leaf water loss (ELWL), relative water content (RWC), photosynthesis and water use efficiency (WUE) by disturbing stomatal adjustment, producing reactive oxygen species (ROS), lowering stomatal conductance and destroying the chlorophyll and other pigments. Rape is more susceptible to water deficit stress during reproductive stages which ultimately affect the yield and oil quality. Some important management strategies for drought mitigation in rape, including use of compatible solutes, nutrients, plant growth regulators, different planting methods are also mentioned and discussed in this review paper. [ABSTRACT FROM AUTHOR]

Cumulative microbial respiration reflects microbial activities and their potential to support plant growth, where salt tolerant rhizobacteria can optimize their respiration, and ensure plant survival under salt stress. We evaluated cumulative microbial respiration of different salt tolerant rhizobacterial strains at different salinity levels, and checked their ability to sustain plant growth under natural saline conditions by using maize as test crop. Our results revealed that at the highest EC level (10 dS m−1), strain 'SUA-14' performed significantly better, and exhibited the greatest cumulative respiration (4.2 fold) followed by SHM-13 (3.8 fold), as compared to un-inoculated control. Moreover, results of the field trial indicated a similar trend, where significant improvements in shoot fresh weight (59%), root fresh weight (80%), shoot dry weight (56%), root dry weight (1.4 fold), leaf area (1.9 fold), straw yield (41%), cob diameter (33%), SPAD value (84%), yield (99%), relative water contents (91%), flavonoid (55%), 1000 grain weight (∼100%), soluble sugars (41%) and soluble proteins (45%) were observed due to inoculation of strain 'SUA-14' as compared to un-inoculated control. Similarly, substantial decline in leaf Na+ (34%), Na+/K+ ratio (69%), electrolyte leakage (8%), catalase (54%), peroxidase (73%), and H 2 O 2 (50%) activities were observed after inoculation of 'SUA-14' with a concomitant increment in the leaf K+ contents (70%) under salinity stress than un-inoculated control. Hence, among all the tested rhizobacterial isolates, 'SUA-14' served as the most efficient strain in alleviating the detrimental impacts of salinity on maize growth and yield. The 16S rRNA sequencing identified it as Acinetobacter johnsonii. • Effect of different levels of salt stress on the cumulative microbial respiration was assessed. • Efficiency of salt tolerant PGPR for improving maize growth and yield was compared. • Bacterial strain 'SUA-14' exhibited maximum cumulative respiration under highest level of salinity stress, and proved to be the most efficient strain among others. • Rhizobacterial strains in conferring salinity tolerance to maize. • The 16S rRNA identified SUA-14 as Acinetobacter Johnsonii. [ABSTRACT FROM AUTHOR]

Late sown wheat covers 56% of total cultivated area of wheat in Pakistan which makes it vulnerable to sub and supra optimal temperatures. Although there is no substitutes to timely sowing, techniques are available that could mitigate the harmful effects of late sowing. Therefore; a field study was conducted to evaluate the role of H2O2 in mitigation of negative effects of high temperature at reproductive phase, during 2011-12 and 2012-13. Treatments comprised of two sowing dates (20th Nov and 20th Dec) and foliar application of H2O2 (75 µM) and distilled water at different growth stages (tillering, booting and heading) along with a control (no spray). Crop growth rate and net assimilation rate substantially improved under both sowing dates in response to H2O2. Better performance of wheat regarding growth attributes indicated the positive role of H2O2 in protecting the total soluble proteins. The findings further revealed that H2O2 triggered up-regulation of different antioxidants (SOD, POD, and CAT) which offset the negative impacts of supra optimal temperatures that persisted in late planted wheat. Collectively, we concluded that application of H2O2 at heading stage improved growth and heat tolerance in late sown wheat. [ABSTRACT FROM AUTHOR]

A little is known about the brassica species response to different phosphorus (P) amendments and its effects on accumulation of P, proteins, oil and fatty acids in canola (Brassica napus L.) seeds. The two years field study was conducted to evaluate the yield and quality of canola hybrids (Hyola-401 and Hyola-43) in response to different P management strategies. The two canola hybrids were tested under different P application rates (@ 30 kg ha-1 or 60 kg ha-1) applied through broadcasting and side-drilling, alone and in combination with farmyard manure (FYM). Phosphorus applications have significant positive linear (p>0.05%) effects on yield and yield components in the both canola hybrids. The maximum seed yield (2749±6.96 kg ha-1; 2698±7.67 kg ha-1), oil contents (43.73±0.18%; 42.20±0.20%), protein contents (26.23±0.12%; 26.37±0.12%) and P accumulated in grains (0.52±0.01%; 0.45±0.02%) were recorded in Hyola-43 when fertilized @ 60 kg P ha-1 through side drilling along with FYM during 2004-05 and 2005-06, respectively. Hyola-43 appeared a good crop yielding canola hybrid as compared to Hyola-401. The high oleic and low linolenic acid provide good quality oil during frying process. Two folds increase was observed P accumulation in grain and this increase in endogenous grain P may have significant effects on next crop growth on soils having low inherent P. The study result suggests incorporating of FYM along with P fertilizer to overcome the issues of world inorganic P reserves utilization and for the sustainable higher quality canola production. [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]

Application of poultry manure in agricultural fields is potentially beneficial to agro-ecosystems, but challenging due to its excessive moisture, bad odor, transportation, inconsistent nutrient contents and phytotoxic substances, which may adversely affect the health of those who handle it. Composting as an agricultural best management practices (BMPs), could overcome the above issues. Field experiments were carried out in 2010 and 2011 under semi-aired conditions of Pakistan at the Agronomic Research Area of the University of Agriculture Faisalabad to study the effects of different rates of composted poultry manure (CPM) and levels of irrigation on maize yield and quality supported with an economic analysis. One drought tolerant and one sensitive maize hybrid (H1 = Monsanto-919 and H2 = FH-810, respectively) were sown with three rate of CPM levels (L1 = control with recommended NPK, L2 = 8, L3 = 10 and L4 = 12 t ha-1 CPM) under three irrigation levels (I1 = 300, I2 = 450 and I3 = 600 mm). Statistical analysis revealed that H 1 showed maximum grain yield during both years (7.70 and 7.98 t ha-1 respectively) at I3 with the application of recommended NPK. While the grain yield of H1 during both years was greater at CPM than H2 with the application of recommended NPK under I2. In 2011 optimum biological yield equivalent to 18.20 t ha-1 was recorded in treatment I3H1L1. Grain oil and protein contents were statistically at par in both maize hybrids fertilized with L1 and L4 under I1 condition. The nitrogen uptake was similar in both hybrids under controlled condition. Moreover, water use efficiency (WUE) was significantly enhanced with the application of CPM. The highest net benefit ($1788 ha-1) was achieved by recommended NPK treatment; contrarily, the highest marginal rate of return (35%) was obtained by application of 600 mm ha-1 depth of irrigation water and 12 t CPM ha-1. [ABSTRACT FROM AUTHOR]

Poultry manure (PM) is enriched with uric acid and undigested protein however; the nutrient availability varies in fresh and composted PM. An incubation study was conducted during 2009 in green house at Agronomic Research Farm, University of Agriculture, Faisalabad to examine the changes in availability of nitrogen (N) to maize (Zea mays L.) hybrids with composted and non-composted PM under various irrigation regimes. The experiment was conducted following completely randomized design with factorial arrangement and each treatment was repeated five times. Pre-tested drought tolerant (Monsanto 919) and sensitive (FH-810) maize hybrids were planted at 100% and 75% of field capacity levels (FC). Performance of the maize hybrid (Monsanto 919) under composted PM was better for N content, which resulted in maximum number of leaves per plant (17.40), plant height (147.60 cm), leaf area index (4.99) and transpiration rate (8.50 m mol m-2 s-1). In maize hybrid (FH-810), maximum photosynthesis rate (21.82 μ mol m-2 s-1) was noted under composted PM at 100% FC, while the performance of this hybrid was poor in all other recorded observations at 75% FC. The nitrogen availability was more from composted PM under both conditions (normal & drought). This enhanced the morphological and physiological processes in maize crop. [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]

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]

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]

Rapid industrialization and urbanization have resulted in elevated global temperature over the years consequently disturbing the balance of agro-ecological systems worldwide. Therefore, new eco-friendly agricultural practices for sustainable food production are needed. Mulching could potentially serve the purpose by reducing soil evaporation, conserving moisture, controlling soil temperature, reducing weed growth, and improving microbial activities. Additionally, mulches could provide economical, aesthetic, and environmental advantages to agriculture and landscape. Moreover, in the restoration sites, mulches are widely used for the plantation of trees which need no significant care. Mulches combat with different stress conditions in agricultural lands as well as in landscapes. This review paper focuses on multiple significant impacts of mulches for the production and establishment of different crops in nature. Mulches conserve the soil moisture, enhance the nutrients status of soil, control the erosion losses, suppress the weeds in crop plants, and remove the residual effects of pesticides, fertilizers, and heavy metals. Mulches improve the aesthetic value of landscapes and economic value of crops. This paper also describes some problems associated with various mulch materials. There are contradictions about mulching materials as some researchers favor mulches and others have denoted some concerns. The selection of mulching material is important with respect to crop type, management practices, and climatic conditions. The appropriate mulching technique could provide the aforementioned benefits to the agro-ecological systems. Therefore, the impacts of low-cost, eco-friendly, and biodegradable mulching materials on soil microbes, nutrient balance, plant growth, and soil erosion should be explored in the future. [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]

Maize (Zea mays L.) genotypes collected from different research institutes were evaluated against different standards associated with salinity tolerance/susceptibility under four variable saline treatment strengths S0.8 dSm -1 (T1; Control), S4 dSm -1 (T2), S6 dSm -1 (T3) and S10 dsm -1 (T4) to optimize treatment strengths for screening and to study genotype x environment interaction (GEI) on the basis of shoot length (SL), root length (RL), shoot fresh weight (SFW), shoot dry weight (SDW), root fresh weight (RFW), root dry weight (RDW), sodium concentration in leaf sap (Na+), chloride concentration in leaf sap (Cl-), potassium concentration in leaf sap (K+), total proline contents in leaf sap (PRO) and sodium/potassium ratio (Na+/K+). Under S10 dsm -1, genotype UAC-0020 performed relatively well based on Na+ and Cl- whereas UAC-0036 performed well for K+ and Na+/K+. UAC-0024 was most stable for SFW. Under S4 dsm -1, UAC-0028 was poor in performance for Na+, Na+/K+, SL, PRO and Cl-1; similarly, UAC-0048 showed poor performance for SFW, RFW, SL and PRO; UAC-0041 and UAC-0033 posed least resistance for SL, SFW, RL and RFW, respectively. The rest of the genotypes interacted under all the variable stressful environments either positively or negatively. SL, SDW, RFW, Na+, Cl- and PRO were verified as very good indicators of salinity tolerance in maize plant. Biplot based on Principal Component Analysis (PCA) is reported as an effective technique to study GEI. S4 dsm -1 was proved as best strength to sort out susceptible and S10 dsm -1 to sort out most tolerant genotypes. The best performing genotypes could be considered for further breeding programs. [ABSTRACT FROM AUTHOR]

Increasing water shortage for irrigation is a major constrain to sustainable cotton production. Cotton plant observes reduction in seed cotton yield as well as fibre quality when subjected to drought conditions. Physiological as well as agronomic traits provide useful information for water-deficit tolerance. To find out genotypes having better drought tolerance, 45 genotypes of Gossypium hirsutum L. were studied under two moisture levels i.e. well water and water-deficit stress conditions for two years (2013 and 2014). The experiment was conducted using split plot design under RCBD. All the genotypes behaved differently under both control and water-deficit stress. Genotype x Environment Interaction (GEI) of cotton genotypes with two water levels (Environments) were studied for some selected agro-physiological traits i.e. water potential, osmotic potential, pressure potential and seed cotton yield using AMMI biplot analysis. Results showed that the genotypes VH-291, FH-329, FH-153, IR- 6, FH-159, VH-289, FH-322, MNH-886, S-15 and FH-207 are either stable or showing positive interaction with water deficit conditions for most of the traits under studied. These genotypes can be used in further breeding program for developing varieties suitable for cultivation under water deficit conditions whereas; NS-131, AA-703 and KZ 191 interacted undesirably with water-deficit stress. [ABSTRACT FROM AUTHOR]

Water and nitrogen (N) limitations in soil usually restrict plant growth hence reducing water and nitrogen productivity. Precise irrigation application is vital in water scarce areas of the world, such as Pakistan. Water and N are generally the most important factors in high yielding of crops. This interaction between irrigation levels and N can be analyzed through field experiments in concert with crop simulation models and decision support systems. Recently the use of crop growth models in crop husbandry has become more common to provide the decision support for farmers. The proposed study was conducted at Agronomic Research Area, University of Agriculture Faisalabad, Pakistan during the years 2012 and 2013 to evaluate OILCROP-SUN model under decision support system for agro-technology transfer (DSSAT) for simulating growth, development and achene yield of sunflower hybrid Hysun-33. The experiment was laid out using split plot design with four irrigation levels (control, 45, 60 and 75 mm potential soil moisture deficit) in main plots and three N rates (90, 120 and 150 kg ha −1 ) in sub plots. The model was first calibrated with control irrigation plus 150 kg N ha −1 treatment (I 1 N 3 ), then evaluated (2012) and validated (2013) by utilizing experimental data. The evaluation and validation exhibited that the model simulated anthesis date, maturity date, maximum leaf area index (LAI), total dry matter (TDM), achene yield and oil contents very well with an error of 0–6.15%, 0–3.96%, −25.14 to 6%, −0.37 to 17.75%, −4.58 to 17.12% and −15.04 to 12.15%, respectively. Similarly, root mean square error (RMSE) values for soil water and leaf N contents were ranged from 0.03 to 0.05 cm 3 cm −3 and 0.16% to 0.71%, respectively. While RMSE for crop evapotranspiration (ET) was 29.87 mm in 2012 and 32.56 mm in 2013. The highest achene yield and oil contents were achieved with the control irrigation in combination of 150 kg N ha −1 application. However saving of water (110 mm in 2012 and 120 mm in 2013) with 45 mm potential soil moisture deficit (PSMD) treatment (without significant reduction in sunflower productivity) recognized it as most suitable irrigation scheduling technique under water scarce areas of the world. The results disclosed that OILCROP-SUN model can be efficaciously used for simulation of spring sown sunflower under semi-arid conditions of Pakistan. [ABSTRACT FROM AUTHOR]