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Boron (B) is an essential element for higher plants with a widespread deficiency in agricultural soils. Salinity, another common agricultural problem, aggravates B toxicity in plants. NaCl salinity increases B toxicity symptoms on plants and soluble B concentration in inter- and intracellular compartments in leaves. In many cases salinity and high soil B occur together making the conditions more hostile for the plants e.g. the San Joaquin Valley, California. This study investigates the interactive effects of boron toxicity and different salts including NaCl, Na2SO4 and CaCl2. These three salts were used in three separate experiments and wheat plants were exposed for three weeks to either boron or a salt alone or in combination. Salinity x boron significantly reduced shoot as well as root growth of wheat irrespective of the salt used to develop salinity. Sodium sulphate salinity alone and in combination with boron caused a higher percent reduction in shoot fresh and dry weights followed by sodium chloride and calcium chloride salinity. It shows a differential interaction of these salts with boron that may be due to their differential effect on the uptake of boron or vice versa.

Drought is a most prevalent environmental stress affecting the productivity of rainfed wheat and maize in the semiarid Loess Plateau of China. Sustainable agricultural practices such as intercropping are important for enhancing crop performance in terms of better physiological and biochemical characteristics under drought conditions. Enzymatic and non-enzymatic antioxidant enzyme activities are associated with improved abiotic tolerance in crop plants, however, its molecular mechanism remains obscure. A 2-year field study was conducted to evaluate the influence of intercropping treatment viz. wheat mono-crop (WMC), maize mono-crop (MMC), intercropping maize (IM) and wheat (IW) crops, and nitrogen (N) application rates viz. control and full-dose of N (basal application at 150 and 235 kg ha−1 for wheat and maize, respectively) on chlorophyll fluorescence, gas exchange traits, lipid peroxidation, antioxidative properties and expression patterns of six tolerance genes in both crops under rainfed conditions. As compared with their respective monocropping treatments, IW and IM increased the Fo/Fm by 18.35 and 14.33%, PS-11 efficiency by 7.90 and 13.44%, photosynthesis by 14.31 and 23.97%, C-capacity by 32.05 and 12.92%, and stomatal conductance by 41.40 and 89.95% under without- and with-N application, respectively. The reductions in instantaneous- and intrinsic-water use efficiency and MDA content in the range of 8.76–26.30% were recorded for IW and IM treatments compared with WMC and MMC, respectively. Compared with the WMC and MMC, IW and IM also triggered better antioxidant activities under both N rates. Moreover, we also noted that intercropping and N addition regulated the transcript levels of six genes encoding non-enzymatic antioxidants cycle enzymes. The better performance of intercropping treatments i.e., IW and IM were also associated with improved osmolytes accumulation under rainfed conditions. As compared with control, N addition significantly improved the chlorophyll fluorescence, gas exchange traits, lipid peroxidation, and antioxidant enzyme activities under all intercropping treatments. Our results increase our understanding of the physiological, biochemical, and molecular mechanisms of intercropping-induced water stress tolerance in wheat and maize crops. [ABSTRACT FROM AUTHOR]

Salinity is among major environmental constraints in arid and semi-arid regions of the world that is deteriorating soil fertility and reducing uptake of micronutrients especially Fe and Zn. The crop plants grown in calcareous and high pH soils are inherently low in these mineral nutrients. Wheat (Triticum aestivum L.) is the principal diet for almost one third of world's population. The information regarding the fortification of wheat with Fe and Zn under saline conditions is limited. The soil and foliar application of Fe and Zn may be helpful for improving the nutritional quality of wheat produced from salt-affected land. The aim of present study was to assess the responses of selected wheat cultivars (Faisalabad-2008 and Galaxy-2013) to soil and foliar application of Fe and Zn under saline conditions. Foliar and soil application of Fe and Zn was done individually as well as in combination. The experimental units were replicated thrice in Completely Randomized Design (CRD). The data of various wheat growth, ionic and biochemical parameters including grain yield, total chlorophyll contents, root and shoot length, root and shoot dry weights, Zn, Fe, K, and Na, SOD and CAT enzyme activity were recorded using standard procedures. It was clearly depicted by the results that the presence of salt stress in the growth medium significantly (p ≤ 0.05) deteriorated plant growth and yield. Also, the results showed that Zn and Fe application significantly (p ≤ 0.05) increased wheat plant growth under salt stress. The foliar application proved to be more efficient than soil application. However, the plants that contained combined application (soil and foliar) of Fe and Zn gave maximum yield as well as higher accumulation of Fe, Zn, and K in shoot and grains. It was, therefore, concluded that the combined soil and foliar application of Fe and Zn is an effective strategy to ameliorate micronutrients (Fe and Zn) deficiency in crops grown under salt-affected soil conditions. [ABSTRACT FROM AUTHOR]

Nitrogen (N), the building block of plant proteins and enzymes, is an essential macronutrient for plant functions. A field experiment was conducted to investigate the impact of different N application rates (28, 57, 85, 114, 142, 171, and 200 kg ha−1 ) on the performance of spring wheat (cv. Ujala-2016) during the 2017–2018 and 2018– 2019 growing seasons. A control without N application was kept for comparison. Two years mean data showed optimum seed yield (5,461.3 kg ha−1 ) for N-application at 142 kg ha−1 whereas application of lower and higher rates of N did not result in significant and economically higher seed yield. A higher seed yield was obtained in the 2017–2018 (5,595 kg ha−1 ) than in the 2018–2019 (5,328 kg ha−1 ) growing seasons under an N application of 142 kg ha−1. It was attributed to the greater number of growing degree days in the first (1,942.35°C days) than in the second year (1,813.75°C). Higher rates of N (171 and 200 kg ha−1 ) than 142 kg ha−1 produced more number of tillers (i.e., 948,300 and 666,650 ha−1, respectively). However, this increase did not contribute in achieving higher yields. Application of 142, 171, and 200 kg ha−1 resulted in 14.15%, 15.0% and 15.35% grain protein concentrations in comparison to 13.15% with the application of 114 kg ha−1 . It is concluded that the application of N at 142 kg ha−1 could be beneficial for attaining higher grain yields and protein concentrations of wheat cultivar Ujala-2016. [ABSTRACT FROM AUTHOR]

Salinity is one of the major abiotic stresses that is deteriorating soil fertility and reducing essential nutrients acquisition by plants around the world. Among staple food, wheat can be a primary source of micronutrients like Fe and Zn. The saline/saline-sodic and calcareous soils are deficient in Fe and Zn. In these regards, the aim of present study was to screen out wheat genotypes which can efficiently utilize Fe and Zn in saline conditions. Therefore, ten wheat genotypes (i.e., Ujala-2016, Punjab-2011, Galaxy-2013, Faisalabad-2008, Anaj-2017, SARC-I, SARC-VIII, Lasani-2008, Sehar-2006 and Inqalab-91) were exposed to varying rates of Zn (0.2, 0.4 µM) and Fe (25, 50 µM) under saline and normal conditions in a solution culture experiment. Salinity was developed by using NaCl salt, while the sources of Zn and Fe were ZnSO4.7H2O and FeSO4.7H2O, respectively. The data of various wheat growth and ionic parameters including root/shoot dry weight, chlorophyll contents, Zn, Fe, K and Na concentration in root and shoot of wheat genotypes were recorded using standard procedures. The results showed that Fe and Zn application significantly (p ≤ 0.05) increased wheat plant growth under salt stress. Among tested genotypes, Faisalabad-2008 and Galaxy-2013 performed better under saline conditions with maximum biomass production, Zn, Fe and K absorption. Thus, these both genotypes were found to be good source for future wheat breeding programs or can be grown by farmers owing to efficient Fe and Zn utilization as a gateway toward the production of Fe and Zn biofortified wheat under saline conditions. [ABSTRACT FROM AUTHOR]

Salinity stress is a major abiotic stress limiting the crop production worldwide. Salt accumulation in root zone and uptake of toxic ions (i.e., Na+ and Cl- ) causes disturbance in water uptake by osmotic stress, oxidative stress, salt injury of roots and specific ion toxicity to the plants reducing the crop growth and production. Silicon (Si) treatment to stressed plants exhibits positive effect on growth, physiology and ionic homeostasis of plants. A study was conducted to check the varietal response of bread wheat genotypes against moderate (75 mM NaCl) and strong (150 mM NaCl) saline conditions in hydroponics and stressed plants were treated with exogenous silicon (2 mM) to evaluate it against saline stress in wheat seedling. Fifty days old wheat seedling showed negative response to saline stress under both levels but when treated with Si, its growth traits, tissue health parameters and ionic homeostasis were improved. Exogenous silicon application improved growth traits shoot and root length, fresh and dry weight upto 75% and tissue health parameter i.e., membrane stability index and relative water contents upto 61% as compared to salinity stress. It improved the ionic homeostasis in wheat seedling by decreasing the Na+ uptake upto 43 and 84% and increasing the K+ concentration by 26 to 39% respectively under moderate to strong saline conditions. Different genotypes showed different response against salinity and exogenous Silicon application. Faisalabad-08 and Anaj-17 performed best in all growth, physiological and ionic parameters and also ranked as top varieties in Principle component analysis on the basis of salt tolerance index. It was concluded that Faisalabad-08 and Anaj-17 has higher salt tolerance among all wheat genotypes tested, and silicon treatment to stressed plants increases the salt tolerance and improves growth traits, tissue health and ionic homeostasis in all wheat genotypes. [ABSTRACT FROM AUTHOR]

Limited water availability is one of the important abiotic factor affecting yield of wheat crop. Exogenous application of osmolytes is an important factor in reducing the stress due to water shortage. Keeping in view the role of proline and L-tryptophan (L-TRP) in stress alleviation, a study was carried out at the agricultural research area of the University College of Agriculture and Environmental Sciences, The Islamia University of Bahawalpur, Pakistan, during winter 2015-2016 to evaluate the impact of foliar applied proline and L-TRP on growth and photosynthetic efficiency of wheat grown under limited moisture supply. Drought stress was applied in three levels (I1 = control, I2 = drought stress at tillering stage and I3 = drought stress at grain filling stage) while, foliar application of proline and L-TRP was done in six levels [T1 = control; T2 = proline (10 mM); T3 = proline (20 mM); T4 = L-TRP (10-4 M); T5 = L-TRP (10-4 M) + proline (10 mM) and T6 = L-TRP (10-4 M) + proline (20 mM)]. The experimental results revealed that growth and photosynthetic efficiency of wheat were decreased due to reduced water supply. However, exogenously applied proline and L-TRP considerably ameliorated the effect of drought stress. Combined application of L-TRP (10-4 M) and proline (20 mM) showed better results and induced tolerance to drought stress, in comparison with other treatments. Foliar application of proline and L-TRP also enhanced the photosynthetic rate which might be related with the improved photosynthetic pigments. Overall, exogenously applied proline and L-TRP mitigated the adverse effects of moisture deficit on growth and photosynthetic efficiency of wheat crop. [ABSTRACT FROM AUTHOR]

Abstract Since Ni-rich soils are a threat to the environment, growing edible crops on Ni-rich soils can pose a serious risk to human, animal, plant and ecosystem health and, hence, is considered as a challenging task for the researchers. Contrarily, limiting the bioavailability of Ni in such soils upon the addition of suitable amendments cum foliar spray of proteinogenic amino acids having an objective to alleviate stress to crop plants can considerably reduce the environmental risk. In this pot trail, we substantiate the effects of biochar (BR) and zeolite (ZL) addition in the soil along with proline (PN) spray on the resistance, and stress responses of wheat against Ni as well as on Ni translocation and accumulation in wheat plants grown on a Ni-rich soil contaminated by electroplating effluent. The treatments, applied with and without PN spray, involved: no amendment; BR; ZL; and a concoction of both amendments (BR50%+ZL50%). We found that BR50%+ZL50% treatment significantly immobilized Ni in the soil, reduced its accumulation in the shoot, root, and grain, blocked membrane lipid peroxidation and showed an improvement in photosynthetic parameters, the status of antioxidant activities, grain biochemistry and grain yield, compared to the control. Interestingly, exogenous PN spray caused a significant additive effect on the aforementioned parameters in the wheat plants grown on BR50%+ZL50% treated soil. Our results involved a reduced Ni bioavailability in wheat rhizosphere due to BR50%+ZL50% in soil and, furthermore, the additive effect of PN spray to scavenging ROS, obstructing peroxidation of lipid membrane and, thus providing resilience to wheat plant against Ni stress. The suggested technique can make Ni-rich soils suitable for cultivation and production of high-quality food by minimizing Ni bioavailability and toxicity to plants. Highlights • Biochar + zeolite + proline (BR50%+ZL50%+PN) was the best treatment than rest. • The highest reduction in Ni distribution in plant parts was found in BR50%+ZL50%+PN. • ZL+PN and BR50%+ZL50%+PN treatments significantly reduced DTPA-extractable Ni. • The highest alleviation of oxidative stress in plants was found on BR50%+ZL50%+PN. • The highest grain quality was found on BR+PN and BR50%+ZL50%+PN treatments. [ABSTRACT FROM AUTHOR]

Salinity is an important abiotic stress affecting agricultural productivity in Pakistan. In order to meet the country's requirement, the sustainability of crop production is pre-requisite. A hydroponic experiment was conducted to check the response of wheat cultivars against salinity with salicylic acid application. There were four wheat varieties (Lasani-2008, MH-97, SARC-1 and Iqbal-2008), two levels of NaCl (75 mM and 150 mM) and two levels of salicylic acid (0.25 mM and 0.50 mM) along with their respective controls. This experiment was conducted in a completely randomized design with factorial arrangement and five replications of each. After one month of transplanting in hydroponic culture, plant growth parameters and chlorophyll contents were determined. The results showed that plant growth was highly affected at both levels of NaCl treatments, while a decrease in chlorophyll contents and K+ concentration was observed. However, the application of salicylic acid (0.25 mM and 0.50 mM) overcame the adverse effects of salinity and improved the plant growth significantly (P≤0.05) by increasing superoxide dismutase and catalase activities. The application of 0.25 mM salicylic acid in the presence of 75 mM NaCl enhanced shoot dry weight by 21% and 30.68% in Lasani-2008 and Iqbal- 2008, respectively as compared to their respective control. The activity of superoxide dismutase was enhanced from 2.67 to 3.15 (gmol/g Fw) in SARC-1 when salicylic acid was applied in the presence of 150 mM NaCl. Under tested condition, SARC-1 performed better than others tested wheat genotypes. In conclusion, salicylic acid improved the performance of wheat varieties in saline conditions. [ABSTRACT FROM AUTHOR]

Cadmium (Cd)-contamination of agricultural soils has been receiving attention worldwide due to its entry into food crops such as wheat ( Triticum aestivum L.). Little is known regarding the use of organic carbon (OC) sources in alleviating Cd toxicity in cereals. The current experiment was aimed to study the effects of different OC sources on the Cd accumulation by wheat. A pot study was conducted to determine the effects of rice husk biochar (RHB), farmyard manure (FYM), and lignite (LT) either alone or in combination on crop growth, Cd bioavailability and health risk assessment. The results proved that the application of OC sources like RHB, FYM, and LT either alone or in combination were highly effective in enhancing the wheat growth and yield as well as in minimizing the phyto-available fraction of Cd and its transfer to edible tissue of wheat. The RHB was the most efficient source in enhancing the plant growth and reducing the Cd concentration in wheat tissues. RHB increased grain yield by 91% and decreased Cd concentration in shoot, roots, grains, and bioavailable fraction of Cd by 67, 69, 62.5, and 74% than control, respectively. The RHB reduced the daily Cd uptake and health risk index in adults in comparison to control. Overall, where un-amended soil resulted in diminished plant productivity, the application of other OC sources also significantly proved their potential to enhance the dry weight and grain yield, suggesting that these OC sources may be used aiming to minimize the Cd concentration in crops. However, there is still a need to explore the potential of different OC sources in combination with other frequently available amendments for their large scale implementation in metal-contaminated soils. [ABSTRACT FROM AUTHOR]

Boron (B) is an essential nutrient required in very small amount by crop plants and it can become toxic to plants when present in slightly higher amount. Increasing concentration of B is often found in association with salinity. The presence of salinity and high B may result in synergistic or antagonistic effects on plant growth. A hydroponic trial was conducted to evaluate the influence of various levels of B on the growth, physiological and biochemical responses of salt tolerant and sensitive wheat genotypes under saline conditions. The present study comprised of twelve treatments including four rates of B (control, 0.5, 1 and 1.5 mM) and three levels of salinity (control, 100 and 200 mM NaCl). Two salt tolerant (SARC-I and Sehar-2006) and two salt sensitive (Koistan-90 and MH-97) wheat genotypes were used. The tested salt tolerant and sensitive wheat genotypes showed significant variations and responded differently to salinity and B individually as well as in combination. The salt tolerant genotypes showed better growth due to high antioxidant activity, maintenance of photosynthesis and stomatal conductance and low leaf Na, B and Cl concentration in the presence of individual and combined stresses of salinity and high B as compared to sensitive genotypes. The highest level of salinity and B in combination caused the highest reduction in plant growth as compared to their respective controls. However the interactive effect of salinity and boron was antagonistic as increasing salinity reduced boron toxicity while increasing boron reduced harmful effects of salinity on growth and physiological attributes of wheat. [ABSTRACT FROM AUTHOR]

Salinity is an abiotic stress affecting the growth and development of plants like wheat and genotypes of wheat differ in their response to salinity. These genotypic variations in wheat for salinity tolerance are due to physiological and biochemical differences. The objective of this study was to assess the genotypic differences between two wheat genotypes 25-SAWSN-12 and 25-SAWSN-8. A hydroponic study with four replications was carried out; two treatments control and salinity (125 mM NaCl) were applied. Salinity reduced shoot and root growth, a reduction in water relations, photosynthetic attributes and membrane stability index (MSI) was also observed in both genotypes but this reduction was more conspicuous in 25-SAWSN-8 than in 25-SAWSN-12. The ionic composition showed that 25-SAWSN-12 had more K+, and less Na+ and Clconcentrations in its shoot and root while 25-SAWSN-8 behaved in an opposite way. It seems that the reduction in growth, water relations, photosynthetic attributes and membrane stability was due to the toxic effect of Na+ and less uptake of K+ caused by salt stress. The genotype 25-SAWSN-12 was able to cope with drastic effects of Na+ therefore it showed better growth under salinity as compared to 25-SAWSN-8. [ABSTRACT FROM AUTHOR]

Cultivation of crops in salt-affected soils is a major challenge for growers. Despite the use of multiple amendments, salinity stresses adversely affect the crops to some extent. On the other hand, imbalance in the use of boron (B) as a nutrient also creates toxicity. Mismanagement of B fertilizer application decreases the growth and yield of crops. It is necessary to study in depth the adverse effects of salinity and B toxicity. This is why the current research work was conducted in a glass house at Murdoch University, Perth, Australia. The aim of study was to investigate the influence of salinity and B toxicity on carbohydrate partitioning, growth, and ionic composition of two Australian wheat varieties. There were four treatments, i.e., control, high B (15 kg ha−1), salinity (15 dS m−1), and B + salinity. The results showed that the salt-tolerant Halberd (HB) variety accumulated more Na+, B, and Cl− in their leaf sheath and kept the leaf blades free of these toxic ions as compared to the sensitive variety Westonia (WS). Water-soluble carbohydrate (WSC; i.e., glucose, sucrose, fructose, and fructans) concentration increased in response to individual as well as combined constrains of soil salinity and toxic B in the leaf blade of both tolerant and sensitive wheat varieties, but the increase was higher in the tolerant variety as compared to the sensitive one. The concentration of WSCs in leaf sheath of the salt-tolerant wheat variety was increased in response to stress conditions, but those remained low in salt-sensitive ones. Therefore, the salt-tolerant HB genotype was found to be a good source for future wheat breeding programs or to be grown by farmers in B toxic, saline, and B toxic–saline conditions. [ABSTRACT FROM AUTHOR]

Understanding the mode of temporal maintenance of plant pathogens is an important domain of microbial ecology research. Due to the inconspicuous nature of microbes, their temporal maintenance cannot be studied directly through tracking individuals and their progeny. Here, we suggest a series of population genetic analyses on molecular marker variation in temporally spaced samples to infer about the relative contribution of sexual reproduction, off-season survival and migration to the temporal maintenance of pathogen populations. We used the proposed approach to investigate the temporal maintenance of wheat yellow rust pathogen, Puccinia striiformis f.sp. tritici ( PST), in the Himalayan region of Pakistan. Multilocus microsatellite genotyping of PST isolates revealed high genotypic diversity and recombinant population structure across all locations, confirming the existence of sexual reproduction in this region. The genotypes were assigned to four genetic groups, revealing a clear differentiation between zones with and without Berberis spp., the alternate host of PST, with an additional subdivision within the Berberis zone. The lack of any differentiation between samples across two sampling years, and the very infrequent resampling of multilocus genotypes over years at a given location was consistent with limited over-year clonal survival, and a limited genetic drift. The off-season oversummering population in the Berberis zone, likely to be maintained locally, served as a source of migrants contributing to the temporal maintenance in the non- Berberis zone. Our study hence demonstrated the contribution of both sexual recombination and off-season oversummering survival to the temporal maintenance of the pathogen. These new insights into the population biology of PST highlight the general usefulness of the analytical approach proposed. [ABSTRACT FROM AUTHOR]

A study was conducted at Arid Zone Research Institute, Dera Ismail Khan, Pakistan during the year 2012-13 to find out the most effective method of herbicide application for controlling weeds in wheat crop. Herbicides i.e. Buctril super @ 750 mL ha-1, Puma super @ 1250 mL ha-1 and Buctril super @ 750 mL ha-1 + Puma super @ 1250 mL ha-1 were applied at first irrigation. These herbicides were also sprayed on moist field after first irrigation. The results revealed that Buctril super + Puma super spray suppressed weed density by 73.9 %, fresh weed weight by 72.4% and dry weed weight by 64.0%, respectively as compare to control. Maximum (111) days taken to 50% heading were noted in control treatment. The application of Buctril super + Puma super delayed maturity to 161 days, produced tallest plants of 112cm, highest number of 3.0 tillers per plant, maximum spike length of 10.2cm, maximum 59.6 grains per spike, biomass yield 14.55 t ha-1, heaviest grains weight (52g) and highest grain yield of 6081 kg ha-1. Buctril super in combination with Puma super spray proved to be an efficient method than application with irrigation water. [ABSTRACT FROM AUTHOR]

This study reports the relationship of the leaf ionic composition with the grain yield and yield components of wheat in response to salinity x sodicity and salinity alone. The study was conducted in soil culture in pots with three treatments including control (ECe 2.6 dS m- 1 and SAR 4.53), salinity (ECe 15 dS m- 1 and SAR 9.56), and salinity x sodicity (ECe 15 dS m- 1 and SAR 35). The soil was treated before being put in the pots and the pots were arranged in a completely randomized factorial arrangement with five replications. The seeds of three wheat genotypes were sown directly in the pots and the study was continued till the crop maturity. At booting stage, the leaf second to the flag leaf of each plant was collected and analyzed for sodium (Na+), potassium (K+), and chloride (Cl-). At maturity, plants were harvested and data regarding grain yield and yield components were recorded. This study shows that salinity and sodicity in combination decreases the grain yield of wheat more than the salinity alone with a greater difference in the sensitive genotype. This study also shows that as for salinity, the maintenance of lower Na+ and higher K+ concentrations and higher K+: Na+ ratio in the leaves relates positively with the better development of different yield components and higher grain yield in saline sodic soil conditions. Although, the leaf Cl- concentration was increased significantly by salinity as well as salinity x sodicity and would have affected the growth and yield, yet it does not seem to determine the genotypic tolerance or sensitivity to either salinity or salinity x sodicity. [ABSTRACT FROM AUTHOR]

The information of soil compaction effects on growth and yield of crops for saline and waterlogged soils is scanty. A pot experiment was conducted on a sandy clay loam soil during 2001–2002 to study the interactive effects of soil compaction, salinity and waterlogging on grain yield and yield components of two wheat (Triticum aestivum) genotypes (Aqaab and MH-97). Compaction was achieved at 10% moisture level by dropping 5 kg weight, controlled by a tripod stand for 20 times from 0.6 m height on a wooden block placed inside the soil filled pots. Soil bulk density of non-compact and compact treatments was measured as 1.21 and 1.65 Mg m−3, respectively. The desired salinity level (15 dS m−1) was developed by mixing the required amount of NaCl in soil before filling the pots. Waterlogging was developed by flooding the pots for 21 days both at tillering and booting stages. Compaction aggravated the adverse effect of salinity on grain yield and different yield components of both the wheat genotypes. Average reduction in grain yield was 44% under non-compact saline conditions against 76% under compact saline conditions. Similarly, the reduction was about 20% more for 100 grain weight and shoot length, 30% more for number of spikelets per spike, 37% more for number of tillers per plant, and 32% more for straw weight in compact saline treatment than in non-compact saline treatment. Compaction alone caused a reduction of 36% in grain yield. The effect of waterlogging on grain yield and yield components was mostly not changed significantly due to compaction. Rather waterlogging mitigated the effect of compaction for most of the yield components except for number of spikes per plant. Therefore, as for normal soils, the cultivation of salt-affected soils should employ implements and techniques which minimize compaction of root zone soil. The effect of soil compaction can also be minimized by light irrigations with short intervals and by using a stress tolerant crop genotype. [Copyright &y& Elsevier]

Soil compaction affects plant growth by causing increased resistance to root penetration and a decreased uptake of water and ions. A pot experiment was conducted to study the effect of soil compaction in conjunction with the soil salinity and waterlogging on root growth and leaf ionic composition of two wheat genotypes (Aqaab and MH-97). Compaction was achieved at a 10% soil moisture content by dropping 5 kg weight, controlled by a tripod stand for 20 times from 0.6 m height on a wooden block placed inside the soil-filled pots. Soil bulk density of non-compact and compact treatments was measured as 1.21 and 1.65 Mg m−3, respectively. The desired salinity level (15 dS m−1) was developed by mixing required amount of NaCl in the soil before filling the pots. Waterlogging was developed by flooding the pots for 21 days both at tillering and booting stages. Compaction significantly reduced the root length density (RLD) of both the wheat genotypes while the combined effect of compaction×salinity was more drastic on root length density than compaction alone. Waterlogging however, did not decrease the root length density, rather it mitigated the effect of compaction. Compaction decreased the concentration of K+ and K+:Na+ ratio in leaves. Salinity also decreased the concentration of K+ and K+:Na+ ratio, but increased the concentrations of Na+ and Cl− in the crop leaves. Salinity and compaction interacted to cause a greater reduction in K+ concentration and the K+:Na+ ratio, while there was lesser increase in the concentrations of Na+ and Cl− compared with salinity alone. Waterlogging also decreased the concentration of K+ and K+:Na+ ratio in leaves. It intensified the effect of salinity but decreased the effect of compaction on leaf ionic composition. Therefore, the effect of compaction on root growth and ion uptake is more severe under salt-affected soil conditions than under normal soil conditions while occasional waterlogging of a compact soil for a few days makes the soil conditions favorable for root growth both under non-saline as well as saline soil conditions. Also, the performance of a genotype in stressed environment is related to maintenance of higher root length density, leaf K+ concentration and K+:Na+ ratio and lower leaf Na+ and Cl− concentrations. [Copyright &y& Elsevier]

Drought is one of the major abiotic stresses which negatively affects plant growth and development. The current study evaluated the effects of drought on the growth, physiology, and biochemical attributes of wheat seedlings; and examined the role of foliar application of ZnO nanoparticles in alleviating drought-induced effects. Two wheat cultivars i.e., Anaj-2017 and FSD-2018 were grown in soil-filled pots and were subjected to 100% field capacity (FC) (well watered) and 50% of FC (drought stress). Whilst different treatments of ZnO nanoparticles spray included no spray, water spray, and 50, 100, and 150 ppm ZnO. Results demonstrated that drought caused a significant reduction in seedling fresh and dry weights, photosynthetic pigmentation, and antioxidant activities compared with a well-watered treatment. Nevertheless, the application of 100 and 150 ppm of ZnO nanoparticles effectively ameliorated the negative effects of drought and enhanced the performance of both cultivars under drought. Data revealed a significant increase in fresh and dry weight of shoot and root with the application of ZnO nanoparticles. A substantial increase of 73.68% and 28.51% in chlorophyll "a" and 26.15% and 50.02% in chlorophyll "b" was recorded with the application of 100 ppm of ZnO nanoparticles in Anaj-2017 and FSD-2018, respectively over control (0 ppm). The application of these nanoparticles also triggered the antioxidant defense system and protected the crop from oxidative damage. Averaged across different stress treatments, application of 150 and 100 ppm of ZnO nanoparticles increased the peroxidase activity by 60% and 72% in FSD-2018, and 15% and 23% in Anaj-2017, respectively compared with no spray. FSD-2018 outperformed Anaj-2017 regarding its overall performance under ZnO treatments and drought conditions. In a nutshell, it can be concluded that ZnO nanoparticles ameliorated the negative impacts of drought by improving the growth, physiology, and antioxidant defense of both wheat cultivars. • Drought reduced seedling growth, photosynthetic pigmentation, and antioxidant activities. • ZnO NPS efficiently improved growth, and photosynthetic pigments. • ZnO NPs triggered antioxidant defense system for lowering oxidative stress. • FSD-2018 outperformed Anaj-2017 regarding its overall performance under drought conditions. [ABSTRACT FROM AUTHOR]

Better sowing method of a crop leads to better production by ensuring seed placement at proper depth and resulting in uniform emergence and crop stand. Different sowing methods are being used by farmers according to their wisdom but a limited information is available about the production potential and economic efficiency of sowing methods. To evaluate better sowing method for better production of wheat and its economic efficiency under irrigated conditions was studied through field experiments conducted during year 2017-18 and 2018-19 at Agronomic research Institute, Ayub Agricultural Research Institute, Faisalabad, Pakistan. Five sowing methods such as drill sowing (DS), bed sowing (BS), broadcasting (BC), broadcasting augmented with furrows (BAF) and ridge sowing (RS) were evaluated in RCBD replicated thrice. Data regarding yield and yield contributing factors during both years of study revealed that performance of wheat was better when sown by DS and BAF. DS and BAF produced significantly higher plant population 10.84% and 9.84%, grains per spike 13.45%, 12.11%, 1000-grain weight 4.96% and 4.53% and grain yield 11.95% and 11.19% respectively during 2018-19 and 2020-21 than BC. Moreover a strong correlation of wheat yield was observed with its yield contributing attributes. Economic analysis of different sowing methods during both years of study revealed the profitability of DS and BAF as more benefit-cost ratio (BCR) 7.18, 6.54% over BC, respectively was recorded with these sowing methods. It was concluded that DS and BAF are suitable methods for better wheat production and profitability under irrigated conditions. [ABSTRACT FROM AUTHOR]