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

Although maize (Zea mays L.) crop has high production potential for forage and grain, however it requires efficient managerial practices for optimum yield. Adequate nutrients for optimum growth led to good vegetative and reproductive growth. Field studies were conducted to evaluate the effects of two endogenous seed phosphorus (P); i.e. SLP: seed with low endogenous phosphorus (1.5 mg kg −1 seed dry weight), and SHP: seed with high endogenous phosphorus (3.2 mg kg −1 seed dry weight). Pre-categorized seeds were tested against five rates of exogenous soil P, namely, (1) control: no P (0 kg P ha −1); (2) 50 kg P ha −1; (3) 100 kg P ha −1; (4) 150 kg P ha −1; and (5) 200 kg P ha −1. Seeds having different P contents depicted non-prominent effects on accumulation patterns with few exceptions of P (at physiological maturity (R6) and of potassium (K) (at grain filling (R4) and R6); exogenous P expressed significant effects. Nitrogen (N), P, K, zinc (Zn), and boron (B) exhibited differential accumulation behavior during maize growth. Nitrogen expressed accumulation from tasseling (VT) to R4; however, P, K, Zn, and B depicted remobilization from VT to R6. Maximum accumulation efficiency of P (50.7%), Zn (46.9%), and B (51.4%) was observed from VT to R4 growth, whereas maximum response of K (60.3%) and N (21.8%) was witnessed from R4 to R6, representing variant source-sink capacities. Boron depicted greater remobilization under low exogenous P applications. Results suggest that exogenous P application severely affects nutrient accumulation during pre- and post-grain filling growth. [ABSTRACT FROM AUTHOR]

Agricultural systems all over the world are facing extraordinary pressure in term of squeezed natural resources to meet the increasing food demand of fast growing population in recent times. Water being the most useful natural resource has become scare due to climate change and global warming as it is key input of agronomic crops particularly rice. An experiment was carried out to evaluate the impact of nitrogenous fertilizers on rice productivity under aerobic and anaerobic cultures in green house conditions. In aerobic culture, soil was kept aerated by maintaining 80–100% field capacity while flooded conditions were maintained throughout the cultivation period by putting polythene bags in pots regarding anaerobic culture. Nitrogenous fertilizers include urea, neem coated urea and zinc coated urea. All the nitrogenous fertilizers enhanced the growth, yield and quality attributes of rice plant as compared to control treatment but maximum improvement was recorded by application of zinc coated urea. Application of zinc coated urea produced maximum productive tillers, kernel length, 100-kernel weight and kernels per spikelet. Maximum transpiration rate was also observed by application of zinc coated urea. Application of zinc coated urea produced maximum normal kernels while percentage of opaque, abortive and chalky kernels was significantly reduced. Zinc coated urea was found responsible for maximum production of straw and kernel yield. Anaerobic conditions were also recorded more responsive comparatively. Among the nitrogenous fertilizers, zinc coated urea is recommended to enhance the productivity of rice with good quality kernels under anaerobic culture. [ABSTRACT FROM AUTHOR]

Alfalfa is the world's best fodder due to its high protein, high calcium, low fiber and high digestibility. Experiment was planned to find out the potential in alfalfa breeding material for high biomass yield, quality traits and to understand pattern of inheritance for plant biomass and quality traits. Alfalfa genotypes were crossed with line x tester crossing design. The developed breeding material was evaluated and best cross combinations were selected. Presence of genetic variability in developed germplasm directed to exploit the better forage yield and quality related characters in alfalfa population. Combining ability analyses revealed various magnitude as well as directions. The analysis of general combining ability showed that lines 533624, 601244, 206574, 263154 and 199279, testers 39483 and 40095 were considered as potential parents and crosses 533624 x 39483, 206574 x 39483, 533624 x 672753, 206574 x 672753, 262544 x 40095 and 37522 x 37530 were best crosses on the basis of better yield and good quality traits. Fresh plant weight, plant heights, plant dry weights and crude protein were additively controlled genetically. Total plant height, plant fresh weight, dry weights, number of nodes of each plant, its crude protein contents, ash contents and forage yield per plant may be used as vital factors for the betterment of biomass and forage yield and its quality. Selected crosses from the present study were comparable with commercial varieties. These crosses are suggested to develop the high and better yielding types in alfalfa. [ABSTRACT FROM AUTHOR]

The emphasis of this research was to assess the genotypes which were rich in iron and zinc content in their grains. Genetic diversity was estimated for zinc and iron content in grains along with agro-morphological traits directly related to yield in 85 diverse wheat genotypes. The experiment was carried out in the experimental field of Plant Breeding and Genetics Department, University of Agriculture, Faisalabad using replicated randomized complete block design during 2013-14. The results depicted highly significant differences among all the traits i.e., iron & zinc content in grains, flag leaf area, peduncle length, spikelets per spike, grains per spike, thousand grain weight and grain yield per plant. Mean values of all the traits indicated the presence of genetic variability. WHEAR-TUKURU-WHEAR (83.30 mg/kg), MARVI-2000 (80.98 mg/kg) and PRL'S'/PVN (80.27 mg/kg) had highest means among other genotypes for iron and 89.77 mg/kg, 85.14 mg/kg and 88.49 mg/kg for zinc, respectively. Grain content for iron (Fe) and zinc (Zn) showed positive and significant correlation among them and with yield related traits as well. Cluster analysis grouped germplasm into six clusters on the basis of studied mineral content and agromorphological traits. Cluster 4 contained 10 genotypes showing the best performance for most of the traits contributing for high grain mineral content and high yield. It was suggested that ample genetic diversity was present in the germplasm for the uptake of iron and zinc along with high yield potential. Moreover, it was concluded that selection for micronutrient efficiency could be achieved without affecting yield potential. [ABSTRACT FROM AUTHOR]

Insufficient mobilization of pre-anthesis photosynthates from vegetative sources to reproductive sinks during achene growth and development plays a key role in reduced productivity of sunflower. Among different essential plant nutrients, a micronutrient boron (B) is known to have a prominent role in the mobilization of pre-anthesis reserves. A field experiment was carried out to investigate the role of soil applied boron in the mobilization and partitioning of pre-anthesis photoassimilates in early and late sown sunflower hybrid. Treatments were comprised of sowing dates (S) randomized in main plots and different rates of boron (B) randomized in sub plots. Treatments were S1= Normal sowing (Mid-February); S2= Late sowing (1st week of March) and B1= Control; B2= Water spray; B3= 1.5 kg B ha-1 at button stage; B4= 2 kg B ha-1 at button stage; B5= 2.5 kg B ha-1 at button stage; B6= 1.5 kg B ha-1 at ray floret stage; B7= 2 kg B ha-1 at ray floret stage; B8= 2.5 kg B ha-1at ray floret stage. Soil applied boron significantly improved the dry matter accumulation (fresh and dry weight of leaf, stem, head and whole plant) and mobilization of photosynthates, capitulum diameter, number of achenes per head, 1000-achene weight, achene and biological yield. Moreover, achene oil and protein contents also increased by the soil application of boron. Normal sowing date was more effective for mobilization of reserves. However, application of B (2-2.5 kg ha-1) mitigated the adverse effects of late sowing to a considerable extent. [ABSTRACT FROM AUTHOR]

The impact of soil (1, 2 kg ha−1) and foliar (100, 200 mg L−1) boron (B) with control (no B) was evaluated on phenology and yield formation ofCamelinaeach applied at stem elongation and flowering stages. Foliar (200 mg L−1) or soil B (2 kg ha−1) resulted in earlier flowering and maturity, increased fruit bearing branches (19.68%), number of siliqua, seeds per siliqua (4.6%), biological yield (15%), seed yield (24%), harvest index (11.4%) and oil contents (23%) than no B. Increased fruit bearing branches, seed filled siliqua or seed numbers, harvest index and oil quality can be attributed to changes in dry matter accumulated of stem with simultaneous increase in siliqua dry weight with foliar or soil applied B. In crux, foliar (200 mg L−1) or soil applied (2 kg ha−1) B seems promising to improve seed and oil yield, harvest index ofCamelina sativaunder B deficient condition. [ABSTRACT FROM AUTHOR]

Influence of different phosphorus (P) sources on growth, yield and oil quality of linola was evaluated when randomized in complete block design using three replications. Treatments were control (No P), hydropriming, soil phosphorus (50 kg ha-1), seed inoculation with phosphate solubilizing bacteria (PSB, Bacillus spp.) and seed priming with single super phosphate (2%) alone and combined with reduced soil phosphorus (25 kg P ha-1). Among treatments, hydropriming and seed inoculation reduced seedling 50% and mean emergence time with highest emergence index, seedling fresh and dry weights and chlorophyll contents. Seed inoculation with soil P (25 kg ha-1) produced highest seeds per capsule, 100-seed weight, seed and biological yield, harvest index. Maximum oil percentage, low protein contents and high cost benefit ratio with net economic returns were also found for seed inoculation combined with soil phosphorus. Nonetheless, soil phosphorus application can be reduced when seed inoculation with PSB is employed. [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]

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 field experiment was conducted with the objectives to improve nitrogen use efficiency, reduce the cost of production and improve the wheat yield and quality on sustained basis. Trial was conducted following randomized complete block design with split plot arrangement having three replications. In three main plots, randomization of manure was done as no poultry manure application, 1 t ha-1 layer poultry manure (N=3.96%, P=1.92%, K=1.5%) and 1 t ha-1 broiler poultry manure (N=3.12%, P=1.84%, K=1.5%). In five sub plots, randomization of nitrogen from urea source was done at 0, 25, 50, 75 and 100 kg ha-1. Application of poultry manure (layer or broiler) increased yield components and grain yield significantly. Grain yield, grain crude protein contents, number of fertile tillers, spike length, flag leaf area, fresh weight, dry weight, plant height and number of grains increased with each increasing rate of applied nitrogen however, maximum agronomic nitrogen use efficiency (27.39 kg kg-1), physiological nitrogen use efficiency (41.03 kg kg-1) and 1000-grain weight (37.50 g) were observed in treatment where nitrogen was applied at the rate of 75 kg ha-1. Maximum grain yield and benefit cost ratio were observed where layer poultry manure was applied in integration with 100 kg ha-1 nitrogen. However, economic analysis showed that farmers can get maximum benefits (BCR= 2.6) by applying layer poultry manure in integration with 100 kg N ha-1, or by broiler poultry manure application along with 75 kg N ha-1 (BCR= 2.5). [ABSTRACT FROM AUTHOR]

To compare the effect of planting time and N levels on phenology and seed cotton yield of Bt and non -Bt cotton, an experiment was laid out at Students' Farm, University of Agriculture, Faisalabad, Pakistan. Two cotton cultivars; FH-113 (Bt) and CIM-496 (non-Bt) were planted during mid March and mid May using 115, 145 and 175 kg ha-1 N levels. Planting times were placed in main plots, varieties in sub plots and N levels in sub sub plots in randomized complete block design with three replications. All the interactions (sowing date × varieties, sowing dates × nitrogen levels, varieties × nitrogen levels, sowing dates × varieties × nit rogen levels) were non significant for parameters (Days taken to squaring, flowering, first boll splition, vertical and horizontal flower interval, boll maturation period, node above white flower, node number for first fruiting branch, first fruiting branch height, earliness index, number of monopodial and sympodial branches per plant, average boll weight per plant, seed cotton yield kg ha-1) under discussion except variety × sowing date for seed cotton yield. Mean values for various phenological events like days taken to squaring, first flower and first boll splition, BMP (boll maturation period), first fruiting branch height (cm), first fruiting branch node number and node above white flower varied invariably between Bt and non Bt sown at different times. Vertical as well as horizontal flower intervals remained unaffected. Maximum seed cotton yield was recorded in FH-113 at mid March planting and minimum in CIM-496 at mid May planting. A N level of 145 kg ha-1 gave maximum seed cotton yield against the minimum with 115 kg ha-1. It was concluded that performance of Bt cotton was better in both mid March and mid May planting with respect to seed cotton yield per hectare. [ABSTRACT FROM AUTHOR]