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A considerable amount of rice stubbles (7-10 ton ha-1) are produced yearly in rice-wheat cropping system. Suitable management of these crop stubbles maintains soil health and natural balance of the cropping systems. Rice stubbles management requires number of tillage operations to prepare the seedbed which ultimately delayed the wheat sowing process. Consecutive two-year trail was conducted at Agriculture Extension and Adaptive Research Farm, Gujranwala, Pakistan i.e. 2012-13 and 2013-14, with the objectives to determine the most profitable economical rice residues management technique for this system. Trail was comprised of seven tillage methods; turbo seeder (TS), happy seeder (HS), zone disc tiller drill (ZDT), zero tillage drill (ZTD), ZTD after physical elimination of rice stubbles, ZTD after straw burning, conventional tillage and three nitrogen application timings; all N application at sowing time; 0.5 N at as basal dose + 0.5 N at first irrigation; 0.5 N at first irrigation + 0.5 N at second irrigation. Statistically, higher plant height was noted in turbo and happy seeded wheat as compare to other wheat sowing methods while nitrogen application timings gave maximum plant height where N fertilization was done, 0.5 N during seed bed preparation and 0.5 N at first irrigation. Turbo seeded treatment gave 265.33 fertile tillers m² that were 5%, 7%, 12%, 11%, 6% and 4 % more than HS, ZDT drill, ZTD, conventional ZTD after rice straw removal manually, conventional ZTD after rice straw burning and conventional wheat sowing, respectively. Turbo seeded wheat produced substantial higher spike length compared to other ZT methods. Statistically, maximum grains per spike were recorded in experimental units where wheat cultivation was done with turbo seeder followed by conventional tillage method of wheat sowing. Among nitrogen application timings higher grains per spike were calculated where N fertilizer was applied, 0.5 N during seedbed preparation and 0.5 N at primary watering. Uppermost thousand grain weight (TGW) was recorded in conventional sowing method and it was similar with TS, HS, ZTD, ZTD after physical elimination of rice stubbles and ZTD after straw blazing while, in case of N application timings, utmost TWG was obtained when N fertilization was done half N as basal dose and half at the time of primary irrigation. Turbo seeder treatment gave substantially highest total crop biomass as compared with other sowing methods. Wheat sown with turbo seeder gave 5.69%, 14.95%, 12.18%, 9.33%, 5.1% and 1.99% higher yield than HS, ZDT, zero tillage drill, ZTD after physical elimination of rice stubbles ZTD after straw blazing and conventional method of wheat sowing, respectively. Among nitrogen application timings, higher grain yield was obtained where N fertilization was done with 0.5 N at sowing and 0.5 N at time of primary irrigation. During both year of experimentation, LAI and crop growth rate (CGR) at 75 days after sowing (DAS) and total dry matter (TDM) and leaf area duration (LAD) at 120 DAS was maximum in turbo seeded wheat when N was added 0.5 N dose as a basal and 0.5 N at the time of primary irrigation. Net assimilation rate was higher in turbo seeded wheat when N was added 0.5 N during seedbed preparation and 0.5 N at primary watering. Moreover, highest grain protein contents (12.95%), fat contents (0.85%), and fiber contents (0.14%) were observed in TS experimental unit. Among different zero tillage sowing methods turbo seeder gave better returns and in case of nitrogen application timing the treatment gave better returns when half nitrogen was applied at sowing time and half nitrogen was applied at first irrigation. [ABSTRACT FROM AUTHOR]

The conventional rice production system of Pakistan is escalating due to the higher level of labor involved, shortage of water and higher cost of production due to the rapidly increasing cost of energy resources. Dry direct seeded aerobic rice (DDSAR) is a valuable option to ease the problem of labor, water, and energy resources. In this study, screening of four rice varieties of conventional transplanted rice was evaluated under DDSAR in terms of yield, milling recoveries, grain and cooking quality. Four rice cultivars, viz; Super Basmati; Basmati 2000; Basmati 515 and PS-2 were sown at the Research Station of the Engro Fertilizers, Sheikhupura, Pakistan during three consecutive summer seasons (2016 to 2018). The sowing was accomplished in well prepared dry fields. Each variety performed well in terms of yield and quality traits in DDSAR but in terms of yield, Basmati-515 outperformed the other varieties and showed consistency in yield for three consecutive years of cultivation. PS-2 also gave yield statistically similar to Basmati-515 but maximum cooked grain length (17.1-17.5 mm) and grain elongation ratio (1.69-1.7) was recorded for PS-2. In contrast to other varieties, the minimum head rice percentage (40.5-43.5%) was recorded in PS-2 cultivar besides having the second-highest total milled rice percentage (50.5-73.4%) after Basmati-515 (81.0-82.8%). DDSAR did not affect the cooking quality of rice except bursting. In crux, the cultivation of low land rice cultivars under DDSAR not only maintained or increased the grain yield but also the grain and cooking quality of rice. [ABSTRACT FROM AUTHOR]

Weed infestation is a major problem in direct seeded rice because weeds reduce yield as well as quality of rice. Manual weeding in direct seeded rice is very tedious, time consuming and mostly weather dependent operation. A field experiment was conducted in summer season 2018 to study the comparative efficacy of different pre and post-emergence herbicides in direct seeded rice to control weeds. The experiment was comprised of ten treatments with eight herbicides application viz. pendimethalin at 1137.5 g a.i. ha-1, oxadiargyl 80 g a.i. ha-1, triafaman+ ethoxy sulfuran ethyl 56.25 g a.i. ha-1, pyriftalid+ bensulfuron ethyl 220.32 ml a.i. ha-1, bispyribac sodium+bensulfuran 75 g a.i. ha-1, phenoxaprop 431.25 ml a.i. ha-1, pendimethalin 1137.5 g FB ethoxy sulfuran ethyl 7.5 g a.i. ha-1, oxadiargyl 80 g a.i. ha-1 FB ethoxy sulfuran ethyl 7.5 g a.i. ha-1 and there were two control treatments viz. hand weeding and weedy check. The experiment was laid out in randomized complete block design (RCBD) with three replications. The data related to weed growth, weed dominance analyses and yield parameters were recorded and calculated by following the standard procedures. The results showed that triafaman+ ethoxy sulfuran ethyl gave effective weed control for about 50 days after sowing as compared to other herbicides. Also all the yield related parameters rice were recorded maximum in hand weeding and triafaman+ ethoxy sulfuran ethyl applied treatment. As hand weeding is a very tough operation, application of triafaman+ ethoxy sulfuran ethyl 56.25 g a.i ha-1 as preemergence herbicide is recommended to get effective control of weeds and higher paddy yield in direct seeded rice. [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]

Plant growth regulating substances are involved in the physiological and metabolic processes of plants and enable them to cope with numerous environmental stresses. The effect of exogenously applied brassinolide (BR) with various concentrations (0.01, 0.1, and 1.0 mg L-1) was studied on morphological and physiological traits of Leymus chinensis (Trin.) Tzvelev under room and high temperatures in pots. The experimental results revealed that high temperature stress substantially perturbed growth, photosynthetic pigments, and root activity of L. chinensis; however, the deleterious effects of high temperature were partially ameliorated by the foliar application of BR. Compared to room temperature, high temperature stress decreased the plant height, leaf area, plant fresh and dry weight, chlorophyll a and b content, chlorophyll a/b ratio as well as root activity, while exacerbated the membrane damage as indicated by enhanced production of malondialdehyde (MDA). Accumulation of proline content, soluble protein and sugar content in L. chinensis improved by heat stress, compared with normal temperature; application of BR further improved their production thus aiding in the attainment of tolerance against heat stress. Elevated levels of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) were observed under heat stress compared to room temperature, however, application of BR further proved beneficial in this regard. Our results indicated that BR could improve the growth and development of L. chinensis by enhancing the biosynthesis of photosynthetic pigments, osmolytes and antioxidant enzymes system in plants under both room and high temperature. [ABSTRACT FROM AUTHOR]

Soil temperature, herbicides and their application timings were studied to determine their effect on weed infestation in wheat during 2012-13. A randomized complete block design (RCBD) with split plot arrangement was used to layout the experiment where herbicide application timings viz; T1: 30 days after sowing (DAS) and 40 DAS (T2) were randomized in main plot whereas weedy check (W0), weed free (W1), Affinity 50 WP (carfentrazone + isoproturan) (W2) and Axial 0.50 EC (pinoxaden) + Buctril Super 60 EC (bromoxynil + MCPA) (W3) were kept in sub-plots, respectively. Results showed that herbicides reduced weed density and its dry weight considerably in contrast to weedy check. Moreover, Axial 0.50 EC (pinoxaden) + Buctril Super 60 EC (bromoxynil + MCPA) was found most effective regarding weed control. Overall, chemical weed control led to substantial reduction in weed infestation in wheat. However, yield and yield related attributes like fertile tillers m-2, spikelets per spike, grains per spike, 1000-grain weight, grain yield and harvest index were improved so far in weed control treatments as compared to weedy check whereas soil temperature pertaining to weed emergence rate was recorded as: 6-8 °C ? 8-10 °C ? 10-12°C. [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]

Different light and shade intensities are the main constraints to achieve potential biomass accumulation in Leymus chinensis (Trin.) Tzvelev. An experiment was conducted to explain the physiochemical and morphological adversity triggered by various light intensities. Adverse impacts were lessened with exogenous brassinolide (BR). Treatments consisted of 100% natural light (T0), 100% natural light + 0.1 mg L-1BR (BT0), light shade (70% natural light) (T1), light shade + BR (70% natural light + 0.1 mg L-1BR) (BT1), moderate shade (50% natural light) (T2), and moderate shade + BR (50% natural light + 0.1 mg L-1BR) (BT2). These were completely randomized design treatments with five replicates. Results showed that dry biomass production and endogenous hormone levels (abscisic acid [ABA], zeatin riboside [ZR], gibberellic acid [GA], and indole acetic acid [IAA]) increased, while osmolyte accumulation (soluble sugars and proteins, free amino acids, and proline), antioxidant activity (peroxidase [POD], superoxide dismutase [SOD], and catalase [CAT]), and lipid peroxidation decreased under shade at T0. Treatment T1 depicted the most promising results for these attributes. However, biomass accumulation (33%-56%), osmotic substances (soluble sugars,13%-38%; soluble proteins, 9%-41%; free amino acids, 8%-16%; proline, 11%-41%), and antioxidant enzyme activities (POD, 11%-14%; SOD, 3%-33%; CAT, 4%-23%) increased. On the other hand, lipid peroxidation was reduced by BR application, as indicated by decreased malondialdehyde (MDA) content (7%-31%) and relative conductivity (7%-19%) under both natural and shade conditions. Likewise, the biosynthesis of ABA (2%-22%), ZR (11%-24%), and GA (30%-50%) improved under exogenous BR compared with the control. The IAA contents (22%-28%) decreased under foliar-applied BR compared with the control. Results suggested that light to moderate shade improved the biomass production and physiological performance of L. chinensis, while BR application exhibited further improvement. [ABSTRACT FROM AUTHOR]