Yazar "Jabran, Khawar" seçeneğine göre listele
Listeleniyor 1 - 20 / 38
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Agrodiversity in Turkey: Case study on rice(Springer International Publishing, 2021) Öztürk, Münir; Jabran, Khawar; Hasanuzzaman, MirzaAerobic rice has been introduced during the recent past owing to higher water needs and labor requirements of the conventionally irrigated rice. Agronomic crop management of aerobic rice is still under development. Some high-yielding aerobic rice cultivars have been introduced while efforts are underway to produce more cultivars for different rice-growing areas of the world. Although, the seed rate used across the different aerobic rice ecologies varied (40-80 kg ha-1); however, it can be adjusted according to seed type and specific soil conditions. The aerobic rice can be sown manually or using drill on flat land, furrow-beds or furrow-ridges. Ground covers like plastic and straw mulch can be used to improve soil water retention in water-limited areas. Similarly, wise water management is crucial for the good harvest of aerobic rice. Sprinkler and drip irrigation can importantly be employed for growing aerobic rice in water-scarce environments. Efficient fertilizer and pest management are crucial for harvesting high aerobic rice yields. High weed infestation is the biggest pest problem in the aerobic rice. Herbicides are the salient methods to control weeds. Paddy yields similar to the conventional method can be harvested from the aerobic rice if the crop has been managed properly. © Springer Nature Switzerland AG 2021. All rights reserved.Öğe Allelopathy: Introduction and Concepts(Springer International Publishing Ag, 2017) Jabran, KhawarPlants communicate and influence the growth of other plants (or even microorganisms) through excretion of certain chemical compounds (allelochemicals). The process is called allelopathy. A number of allelochemicals have been reported from different plant species. Most important allelochemicals/allelochemical groups in major field crops (those focused in this book) may include phenolic compounds, benzoxazinoids, sorgoleone, glucosinolates, terpenes, alkaloids, and momilactones. The allelopathic potential of field crops may be utilized for controlling weeds without importing weed control agent into the field. This is possible through channelizing the allelopathic activity of field crops for controlling weeds in form of several techniques. Most importantly, these techniques may include growing the crop cultivars that possess an allelopathic potential. The other important ways may include intercropping of a crop possessing an allelopathic potential with a crop without allelopathic activity [e.g., intercropping of sorghum (Sorghum bicolor (L.) Moench) in cotton (Gossypium hirsutum L.)], including a crop possessing an allelopathic activity in a crop rotation, use of residues from an allelopathic crop as mulch, and use of an allelopathic crop as cover crop for controlling weeds. Most important in future research include determining the mode of action of allelochemicals and their formulation into a commercial weed control product.Öğe Barley Allelopathy for Weed Control(Springer International Publishing Ag, 2017) Jabran, KhawarBarley (Hordeum vulgare L.) is ranked as the fourth most important (area under cultivation and production-wise) among the cereals following maize, wheat, and rice. Barley is among the crops possessing a strong allelopathic activity. Important allelochemicals in barley may include phenolic compounds and alkaloids (e.g., hordenine, gramine). Weeds infesting the barley crop can be suppressed by growing barley cultivars expressing a high allelopathic activity. Similarly, allelopathic mulch material from barley can be applied for controlling weeds in barley and other crops. Breeding efforts can help to improve the allelopathic potential of barley cultivars for an effective and environment-friendly weed control.Öğe Biology and management of two important Conyza weeds: a global review(Springer Heidelberg, 2016) Bajwa, Ali Ahsan; Sadia, Sehrish; Ali, Hafiz Haider; Jabran, Khawar; Peerzada, Arslan Masood; Chauhan, Bhagirath SinghWeed management is one of the prime concerns for sustainable crop production. Conyza bonariensis and Conyza canadensis are two of the most problematic, noxious, invasive and widespread weeds in modern-day agriculture. The biology, ecology and interference of C. bonariensis and C. canadensis have been reviewed here to highlight pragmatic management options. Both these species share a unique set of biological features, which enables them to invade and adapt a wide range of environmental conditions. Distinct reproductive biology and an efficient seed dispersal mechanism help these species to spread rapidly. Ability to interfere strongly and to host crop pests makes these two species worst weeds of cropping systems. These weed species cause 28-68 % yield loss in important field crops such as soybean and cotton every year. These weeds are more prevalent in no-till systems and, thus, becoming a major issue in conservation agriculture. Cultural practices such as crop rotations, seed rate manipulation, mulching, inter-row tillage and narrow row spacing may provide an effective control of these species. However, such methods are not feasible and applicable under all types of conditions. Different herbicides also provide a varying degree of control depending on crop, agronomic practices, herbicide dose, application time and season. However, both these species have evolved resistance against multiple herbicides, including glyphosate and paraquahe use of alternative herbicides and integrated management strategies may providt. Te better control of herbicide-resistant C. bonariensis and C. canadensis. Management plans based on the eco-biological interactions of these species may prove sustainable in the future.Öğe Brassicaceae Allelopathy for Weed Control(Springer International Publishing Ag, 2017) Jabran, KhawarSeveral members of Brassicaceae family possess an allelopathic activity. A number of members of this family (particularly the ones belonging to genus Brassica) are grown as vegetables, herbs, or oilseed crops. Another important characteristic of plant species in family Brassicaceae is their allelopathic activity. Glucosinolates and phenolic compounds are the most important allelochemicals synthesized by the plants in Brassicaceae family. The glucosinolates are converted into several isothiocyanates through enzymatic (myrosinase) activity and express an allelopathic activity. Allelopathic potential of Brassicaceae crops (particularly, Brassica spp., Sinapis alba L. and Raphanus sativus L.) can be used for weed control in agricultural fields. Allelopathic potential of crops from family Brassicaceae may be exploited for weed control by using these as cover crops, growing their cultivars with allelopathic activity, including allelopathic crops of this family in a crop rotation and employing the allelopathic mulch from Brassicaceae crops in agricultural fields.Öğe Choice of nitrogen fertilizer affects grain yield and agronomic nitrogen use efficiency of wheat cultivars(Taylor & Francis Inc, 2018) Hussain, Mubshar; Cheema, Sardar Alam; Abbas, Rana Qaisar; Ashraf, Muhammad Faizan; Shahzad, Muhammad; Farooq, Muhammad; Jabran, KhawarNitrogen use efficiency (NUE) is low in cereals especially in wheat. Different wheat cultivars may vary in NUE due to inherited biological nitrification inhibition (BNI) potential. In this study, three wheat cultivars (Punjab-2011, ARRI-2011 and Millat-2011) were fertilized at the rate of 140kg ha(-1) with three N sources [nitrophos (NP), urea and calcium ammonium nitrate (CAN)]. The soil nitrate (NO3-)-N contents were significantly enhanced coupled with simultaneous decrease in ammonium (NH4+)-N contents in the rhizosphere of cultivar Punjab-2011, fertilized with NP; however, cultivar Millat-2011 receiving urea behaved in contrast. Wheat cultivar Punjab-2011 fertilized with NP had the highest grain yield and agronomic NUE than other treatments due to significant increase in chlorophyl contents, allometric and yield parameters. The highest net benefit was recorded from the cultivar Punjab-2011 fertilized with CAN. In conclusion, use of NP in Punjab-2011 enhanced the grain yield and agronomic NUE.Öğe Comparative Performance of Various Disc-Type Furrow Openers in No-Till Paddy Field Conditions(Mdpi Ag, 2017) Ahmad, Fiaz; Ding Weimin; Ding Qishou; Rehim, Abdur; Jabran, KhawarDifferent furrow openers are required to be evaluated for their suitability to manage rice straw for direct planting of wheat in paddy fields. This study was carried out to assess the straw-cutting ability and draft requirements of four different disc-type furrow openers (notched, toothed, smooth-edge single disc, and double disc) in no-till paddy fields. The openers were attached to an in-field traction rig equipped with S-type load cells, and tested using three operating depths of 30, 60, and 90 mm, and three traveling speeds of 0.1, 0.2, and 0.3 m s(-1). Vertical and horizontal forces acting on the openers were observed using LabVIEW software based data acquisition system. The results of this study indicated that the furrow opener type, operating depth, and speed significantly influenced the horizontal and vertical forces, as well as straw-cutting ability of the furrow openers. The highest draft and vertical force were noted for double disc-type furrow openers. The mean straw-cutting efficiency of notched, toothed, and smooth-edge single disc and double disc furrow openers were 12.4, 46.2, 11.4, and 78.5%, respectively. The double disc furrow opener (DD) produced the lowest level of hair-pinned straw and had the highest straw-cutting efficiency with a value of 88.6% at 90 mm operating depth, and therefore had the best performance in comparison with other furrow openers.Öğe Determination of Morphological and Genetic Diversity of ALS (Acetolactate Synthase)-Herbicide-Resistant Echinochloa oryzoides Biotypes in Rice(Friends Science Publ, 2018) Altop, Emine Kaya; Jabran, Khawar; Mennan, HusrevThis work aimed to evaluate the genetic and morphological diversity of 62 biotypes of Echinochloa oryzoides (Ard.) Fritsch. (early watergrass) that are resistant to ALS-inhibitor herbicides (bispyribac-sodium and penoxsulam), using the single sequence repeat (SSR) marker system. To determine the morphological diversity, the weed was grown (five seeds from each population) under screenhouse conditions and morphological characteristics were recorded. Parameter values subjected to a hierarchical clustering analysis showed significant variation among the populations. The genetic variation among populations was determined using the 5'-SSR primer. Populations were classified into two main groups according to the results obtained from the SSR alleles. The allele numbers ranged between 2-6 per locus, the diversity values ranged between 0.27-0.99. The morphological and molecular analyses revealed differences in terms of several quantitative characteristics among the populations examined. Similarities were also found among different E. oryzoides populations grown in different regions in terms of their morphological characteristics, the genetic diversity was found to be higher. There is a potential for the spread of resistance through gene flow owing to high genetic diversity and low differentiation among population of E. oryzoides. Under such situations to prevent further resistance spread, early watergrass management in this area should focus both on reducing seed movement among rice fields and the field management practices such as implementation of crop rotation, use of herbicides with new mode of actions or cultural methods. (C) 2018 Friends Science PublishersÖğe Düzce'de doğal olarak yayılış yapan Heracleum L. taksonları, habitatları ve bu habitatların floristik kompozisyonu(2020) Özkan, Neval Güneş; Yazlık, Ayşe; Jabran, KhawarDüzce ilinde doğal olarak yayılış yapan Heracleum L. taksonları, taksonların bulunduğu habitat tipleri ve bu habitatların floristik kompozisyonunun araştırıldığı bu çalışma 2018 yılında yürütülmüştür. Arazi çalışmaları sonucunda Heracleum platytaenium ve Heracleum sphondylium ssp. ternatum olmak üzere Düzce’de iki farklı Heracleum taksonunun; tarımsal, şehir, kıyı, orman, riparian ve yapay habitatlar olmak üzere altı farklı habitatta yayılış yaptığı belirlenmiştir. Habitatlardan alınan örnek alanlarda Heracleum spp. ile birlikte yayılış yapan 48 familya ve 112 cinse ait 150 takson belirlenmiştir. Araştırma alanında tespit edilen 121 taksona (%80,66) ait fitocoğrafik bölgeler belirlenmiştir. Buna göre; 8 takson Öksin kesime ait olmak üzere 36 takson (%24) Avrupa-Sibirya, 17 takson (%11,33) Akdeniz ve 1 takson (%0,66) İran-Turan kökenlidir. Ayrıca 67 takson (%44,66) geniş yayılışa sahipken 29 takson (%19,33) ise çok bölgelidir veya fitocoğrafik bölgesi bilinmemektedir. Raunkiaer’in yaşam biçimlerine göre taksonlar incelendiğinde; 73 takson (%48,67) Hemikriptofit iken bunu sırasıyla; Terofit (48 takson - %32), Fanerofit (14 - %9,33), Kriptofit (10 - %6,67) ve Kamefit (5 - %3,33) bitkiler takip etmiştir. Son olarak taksonların habitatlara göre hangi bitki taksonları ile bir arada yaşadıkları ayrıca sunulmuştur.Öğe Economic assessment of conventional and conservation tillage practices in different wheat-based cropping systems of Punjab, Pakistan(Springer Heidelberg, 2017) Shahzad, Muhammad; Hussain, Mubshar; Farooq, Muhammad; Farooq, Shahid; Jabran, Khawar; Nawaz, AhmadWheat productivity and profitability is low under conventional tillage systems as they increase the production cost, soil compaction, and the weed infestation. Conservation tillage could be a pragmatic option to sustain the wheat productivity and enhance the profitability on long term basis. This study was aimed to evaluate the economics of different wheat-based cropping systems viz. fallow-wheat, rice-wheat, cotton-wheat, mung bean-wheat, and sorghum-wheat, with zero tillage, conventional tillage, deep tillage, bed sowing (60/30 cm beds and four rows), and bed sowing (90/45 cm beds and six rows). Results indicated that the bed sown wheat had the maximum production cost than other tillage systems. Although both bed sowing treatments incurred the highest production cost, they generated the highest net benefits and benefit: cost ratio (BCR). Rice-wheat cropping system with bed sown wheat (90/45 cm beds with six rows) had the highest net income (4129.7 US$ ha(-1)), BCR (2.87), and marginal rate of return compared with rest of the cropping systems. In contrast, fallow-wheat cropping system incurred the lowest input cost, but had the least economic return. In crux, rice-wheat cropping system with bed sown wheat (90/45 cm beds with six rows) was the best option for getting the higher economic returns. Moreover, double cropping systems within a year are more profitable than sole planting of wheat under all tillage practices.Öğe Effect of different water management strategies on competitive ability of semi-dwarf rice cultivars with Echinochloa oryzoides(Elsevier Sci Ltd, 2019) Altop, Emine Kaya; Şahin, Meral; Jabran, Khawar; Phillippo, Colin J.; Zandstra, Bernard H.; Mennan, HüsrevWeeds are among the major biotic factors that reduce rice productivity. Alternative weed control methods are required in the wake of problems, such as increasing number of herbicide-resistant weed species and environmental pollution. In this research work, we evaluated the weed-suppressive effects of water levels and rice cultivars against an important rice weed Echinochloa oryzoides (Ard.) Fritsch. The studies comprised three water levels [low (5 cm), medium (15 cm) and high (25 cm)], three medium-grain rice cultivars (Ronaldo, Nembo and, Cameo) and three weed levels [high weed density (> 30 plants m(-2)), low weed density (< 10 plants m(-2)), and weed-free]. Weed-free condition helped the rice plants achieve excellent growth and development, and resulted in the highest grain yield, while weedy condition hampered the growth and productivity of rice cultivars. Water levels had the greatest impact on weeds, rice growth, and paddy yield. A standing layer of water (high water level i.e., 25 cm in particular) not only had a highly suppressive effect against weeds, but it also helped to enhance the growth and yield of rice cultivars. Deep and shallow water levels respectively caused an increase in the leaf area, number of tillers, and dry weight of rice cultivars, particularly for Ronaldo. Ronaldo performed better than other cultivars in terms of growth and competitiveness either under weedy or weed-free conditions. This work concludes that maintaining a water layer (15-25 cm) in rice fields could produce multiple beneficial effects including improved rice growth and decreased weed growth, resulting in high rice productivity.Öğe Growth and physiology of basmati rice under conventional and water-saving production systems(Taylor & Francis Ltd, 2017) Jabran, Khawar; Ullah, Ehsan; Akbar, Nadeem; Yasin, Muhammad; Zaman, Umar; Nasim, Wajid; Hussain, MubsharConventionally flooded rice (CFR) requires enormous water and labor inputs. Water scarcity aspires for cultivation of water-saving rice. Growth response and physiology of basmati rice genotypes under the water-saving production systems has not been reported yet. Studies were conducted for 2 years to compare the growth and physiology of three rice cultivars (Super Basmati, Basmati-2000 and Shaheen Basmati), under high (CFR), medium (alternate wetting and drying [AWD]) and low water input (aerobic rice [AR]) systems. Leaf area index, crop growth rate, leaf area duration and dry matter accumulation were higher for AR followed by AWD and CFR, respectively. Shaheen Basmati had a lower growth and relative water contents than Super Basmati and Basmati-2000, probably due to its shorter stature and shorter life cycle. Photosynthetic rate and stomatal conductance of rice cultivars in the different production were affected only at reproductive stage. Basmati-2000 grown as AR had the highest photosynthetic rate followed by the same cultivar under AWD. The results of this study provide us an idea that basmati cultivars can attain a high growth and development with low water input. This would be helpful to grow rice successfully under water-short rice-growing environments.Öğe High carbon dioxide concentration and elevated temperature impact the growth of weeds but do not change the efficacy of glyphosate(Wiley, 2018) Jabran, Khawar; Doğan, Mehmet NedimBACKGROUNDGlobal climate changes may impact the growth and management of weed species. The aim of this work was to evaluate the impact of recent climate changes on the growth of weeds and herbicide efficacy. The effects of temperature, carbon dioxide (CO2), and herbicide on growth and control of Bromus tectorum L., Hordeum murinum L., and Lactuca serriola L. were studied. Treatments included: control or ambient environment (CO2 concentration 400-450 ppm; temperature 20/10 degrees C day/night); elevated temperature (CO2 concentration 400-450 ppm; temperature 25/15 degrees C day/night); high CO2 and elevated temperature (CO2 concentration 800-900 ppm; temperature 25/15 degrees C day/night); high CO2 (CO2 concentration 800-900 ppm; temperature 20/10 degrees C day/night). Glyphosate rates (active ingredient) used in the experiment were: 0 g ha(-1) (untreated control); 360 g ha(-1); 720 g ha(-1); 1080 g ha(-1); 1440 g ha(-1) (recommended rate), and 2880 g ha(-1). RESULTSHigh CO2 concentration and high CO2 concentration plus high temperature improved the biomass and growth parameters of weeds in the studies. In general, high temperature had a neutral, negative or slightly positive effect on the growth of weed species. Climatic conditions did not affect the activity of glyphosate; its application provided equal and effective weed control under both CO2 and temperature levels and their combinations. CONCLUSIONThe positive effect of high CO2 concentration on the growth of weeds does not impact the activity of glyphosate. (c) 2017 Society of Chemical IndustryÖğe Identification of phytotoxins in different plant parts of Brassica napus and their influence on mung bean(Springer Heidelberg, 2018) Mehmood, Azhar; Naeem, Muhammad; Khalid, Farhan; Saeed, Yousaf; Abbas, Tasawer; Jabran, Khawar; Javaid, Muhammad MansoorPlants in Brassica genus have been found to possess strong allelopathic potential. They may inhibit seed germination and emergence of subsequent crops following them in a rotation system. Series of laboratory and greenhouse experiments were conducted to determine the allelopathic impacts of Brassica napus L. against mung bean. We studied (1) the effects of aqueous extract (5%) of different plant parts (root, stem, leaf, flower, and whole plant) of B. napus, (2) the effects of leaf and flower extracts of B. napus at 0, 1, 2, 3, and 4% concentrations, and (3) the effect of residues of different B. napus plant parts and decomposition periods (0, 7, 14, and 21 days) on germination and seedling growth of mung bean. Various types of phenolics including quercitin, chlorogenic acid, p-coumeric acid, m-coumaric acid, benzoic acid, caffeic acid, syringic acid, vanillic acid, ferulic acid, cinamic acid, and gallic acid were identified in plant parts of B. napus. Among aqueous extracts of various plant parts, leaf and flower were found to have stronger inhibitory effects on germination and seedling growth traits of mung bean, higher concentrations were more toxic. The decomposition period changed the phtotoxic effect of residues, more inhibitory effect was shown at 14 days decomposition while decomposition for 21 days reduced inhibitory effect. The more total water-soluble phenolic was found in 5% (w/v) aqueous extract and 5% (w/w) residues of B. napus flowers at 14 days of decomposition (89.80 and 10.47 mg L-1), respectively. The strong inhibitory effects of B. napus should be managed when followed in rotation.Öğe Impact of different crop rotations and tillage systems on weed infestation and productivity of bread wheat(Elsevier Sci Ltd, 2016) Shahzad, Muhammad; Farooq, Muhammad; Jabran, Khawar; Hussain, MubsharCrop rotation and tillage systems have important implications for weed infestation and crop productivity. In this study, five tillage systems viz. zero tillage (ZT), conventional tillage (CT), deep tillage (DT), bed sowing (60/30 cm with four rows; BS1) and bed sowing (90/45 cm with six rows; BS2) were evaluated in five different crop rotations viz. fallow-wheat (FW), rice-wheat (RW), cotton-wheat (CW), mungbean-wheat (MW) and sorghum-wheat (SW) for their effect on weed infestation and productivity of bread wheat. Interaction between different tillage practices and cropping systems had significant effect on density and dry biomass of total, broadleaved and grass weeds, agronomic and yield-related traits, and grain yield of bread wheat. The un-disturbed soils (ZT) under fallow-wheat or mungbean-wheat rotations favoured the weed prevalence (a total weed dry biomass of 72.4-109.6 and 105.6-112.1 g m(-2) in first and second year, respectively). Contrary to this, the disturbed soils (CT, DT, BSI and BS2) had less weed infestation with either of the rotations (a total weed biomass of 0.4-7.1 and 1.1-5.4 g m(-2) in first and second year, respectively). Sorghum-wheat rotation had strong suppressive effect on weed infestation in all tillage systems. The impact of crop rotation was more visible during second year of experimentation. Bed sown wheat (BS1 and BS2) in mungbean-wheat rotation had the highest wheat grain yield (6.30-6.47 t ha(-1)) compared to other tillage systems in different crop rotation combinations. (C) 2016 Elsevier Ltd. All rights reserved.Öğe Influence of Nitrogen Fertilization Pattern on Productivity, Nitrogen Use Efficiencies, and Profitability in Different Rice Production Systems(Springer International Publishing Ag, 2021) Ishfaq, Muhammad; Akbar, Nadeem; Zulfiqar, Usman; Ali, Nauman; Jabran, Khawar; Nawaz, Mohsin; Farooq, MuhammadThe major challenge in sustainable rice production is to achieve the goals of increasing crop productivity, profitability, and resource use efficiency. Production systems (PS) and nitrogen (N) management patterns are two key agronomic practices influencing crop performance, profitability, water use efficiency (WUE), and N use efficiency (NUE). So, this study was conducted to check the influence of split application of N on rice productivity, NUE and profitability under dry direct-seeded rice (DDSR) and transplanted rice (TPR) systems. A field study was conducted in the summer season of 2017 and 2018 to investigate the influence of two PS (dry direct-seeded rice = DDSR and transplanted rice = TPR) and six N management treatments (N-1 = control, N-2 = 50 kg N ha(-1) as basal, N-3 = 100 kg N ha(-1) as basal, N-4 = 150 kg N ha(-1) as basal, N-5 = 100 kg N ha(-1) in three splits and N-6 = 150 kg N ha(-1) in three splits) on crop productivity, profitability, and resource use efficiency. Yield-related traits, spikelet sterility, WUE, and profitability aspects were significantly influenced by PS. All aspects of crop performance, kernel quality, N uptake, and NUE (except NUE on biomass basis = NUEB) were affected by N management pattern, while no significant interaction between PS and N management was observed for any aspect. On average, DDSR improved the productive tiller density (26%), biological yield (16%), WUE (14%), and NUEB (27%) as compared with TPR. Similarly, DDSR reduced the cost of production (31-43%), while maintaining statistically similar paddy yields and reducing total water inputs (5-17%) in comparison with TPR. Among N management pattern, 100 kg N ha(-1) in three splits increased paddy yields (44%), and WUE (42%) as compared with the basal application of 100 kg N ha(-1). Similarly, application of N at 100 kg ha(-1) in three splits improved the total N uptake (42%), agronomic NUE (146%), apparent recovery efficiency (226%) while reducing the spikelet sterility (28%) as compared with the basal application of 100 kg N ha(-1). The DDSR has the potential to maintain or increase yield, WUE, NUE, and economic returns. While, split application of N at 100 kg ha(-1) either in DDSR or TPR not only increased the SPAD-chlorophyll value, WUE, NUE, and economic returns but also reduced the spikelet sterility.Öğe Integrated weed management in maize cultivation: an overview(Burleigh Dodds Science Publishing Ltd, 2017) Jabran, Khawar; Hussain, Mubshar; Chauhan, Bhagirath Singh…Öğe Inter-row hoeing for weed control in organic spring cereals-Influence of inter-row spacing and nitrogen rate(Elsevier Science Bv, 2018) Melander, Bo; Jabran, Khawar; De Notaris, Chiara; Znova, Liubava; Green, Ole; Olesen, Jurgen E.Inter-row hoeing has become increasingly important for weed control in organic spring cereals since the introduction of automatic steering systems. The technology requires a widening of current inter-row spacing for spring cereals in order to provide sufficient room for accurate operation of a hoe share between crop rows. However, there is considerable uncertainty about the optimal combination of inter-row hoeing, inter-row spacing and nitrogen (N) rate in terms of weeding effectiveness and crop yield. The aim of this study was to investigate the effect on weed and crop growth of the interaction between five inter-row spacings (125, 150, 200, 250, and 300 mm) and two N rates (50 and 100 kg NH4-N ha(-1)). Three field experiments were conducted in spring barley and two in spring wheat. One hoeing pass was applied for each inter-row spacing using a share width that worked 15-47 mm from the crop row. The immediate effect on weed numbers following hoeing was a 80-90% reduction in barley and a 63-80% reduction in wheat, but with no significant differences between spacings and N rates. However, the effect on weed biomass at crop anthesis was minor in barley because the crop itself substantially suppressed weed growth. Spring wheat was less competitive and inter-row hoeing reduced weed biomass by 60-70% compared to the standard 125 mm spacing without hoeing. The widening of inter-row spacing appeared not to reduce crop yield or grain quality. Prerequisites for successful inter-row hoeing in spring cereals include retained crop stands when increasing inter-row spacing and the avoidance of crop injuries from inaccurate steering.Öğe Maize Allelopathy for Weed Control(Springer International Publishing Ag, 2017) Jabran, KhawarSeveral natural compounds (allelochemicals) are produced in maize (Zea mays L.), which help its plants gain competitive ability and defense against the pests. Benzoxazinoids are most important of these compounds. Phenolic compounds are the other important allelochemicals found in maize. Allelopathic potential of maize can be used to suppress weeds in maize and other crops. Most important technique in this regard may be the growing of maize cultivars that possess an allelopathic potential and are capable to suppress the weeds. Two other important methods that may be employed to control weeds through maize allelopathy include the use of allelopathic plant parts of maize as mulch and intercropping of allelopathic maize plants in non-allelopathic crops. Allelopathic mulch from maize may be applied to control weeds in maize itself, or other crops. Future research should be focused on improving the allelopathic potential of maize cultivars and conversion of the allelopathic maize residues in the form of a weed control product.Öğe Manipulation of Allelopathic Crops for Weed Control Preface(Springer International Publishing Ag, 2017) Jabran, Khawar…
